1/72 Scale Radio Controlled Electric-Powered Almost-Ready-to-Run US Fletcher Class Destroyer Kit

Big, bold, beautiful-just like the originals. Do you have what it takes to be a “Tin Can Sailor”? Tin Can Sailors fought the largest warships in the world with unarmored and lightly armed ships. Their Fletcher-Class Destroyers were tiny specks […]

FAZER Vei Fathom Blue 1970 Chevelle SS 454 LS6

One of the iconic muscle cars in American history is now part of the popular Fazer VEi line of brushless-powered, hobby-grade RC cars from Kyosho – the 1970 Chevy Chevelle SS! The Chevelle has always been part of the muscle […]

Rescue 17 Fireboat

Elevating Action on the Water There are those products that come to market that get you all riled up as if you were a kid again and what you see on these pages is sure to get you going. As […]

The Top 10 facts about RC toys and RC vehicles!

  http://Red Line Remote Control When it comes to RC toys, remote control toys, RC vehicles and remote control vehicles there are 10 really important things that everyone should know! This is especially the case if you are looking to buy […]

Take to the skies with Telemaster RC Airplane!

Flying remote control airplanes is an amazing hobby that is enjoyed by many people around the world. There is nothing quite like the freedom of the open skies, the adrenaline rush of your first take off, and the satisfaction of […]

 

CARDS Aerodrome Warbirds and Classics Over Michigan – FG Coverage

 

We’ve got on-the-ground coverage from Warbirds and Classics Over Michigan, from reviewer Joe Vermillion!            bird1

Warbirds and Classics Over Michigan is Must-See-RC!

CARDS Aerodrome can be found in a nondescript field just south of Grandledge Michigan, and in this humble reviews opinion is one of the best RC Airfields in the country. (of course I am a member)

With its 1000ft well groomed runway, covered pavilion, covered bleachers, and plenty of room for pilots and spectators alike, it is the perfect first stop for the Indiana Warbirds Alliance!

With 67 pilots, about 150 planes and great weather, the turn out was fantastic! We had plenty of flying and fun all weekend long! Now let me stop blabbering on and let you enjoy the coverage!

Douglas C-124a Globemaster

Carl Bachhubers gigantic One-of Replica of the Douglas C-124a Globemaster flew on and off all weekend. This amazing model has a wingspan of 200″ and is powered by Zenoah G-45’s turning 20X10 3 bladed props, has scratch built retracts and SPC brakes. The nose cargo hold actually opens up to carry an RC Tank! This airframe is a true work of art! Carl is one amazing builder for sure! Well done sir! For more info on Carls amazing builds check HERE.

We had a a great event

The weather cooperated nicely and the event was a huge success! Other then the wind being a little high at times, most pilots got plenty of flight time and really took advantage of this fantastic field! There was barely a moment when there wasn’t three or four planes in the air all weekend.

Indiana Warbird Alliance

The CARDS Club Warbirds and Classics Over Michigan event was the first stop in the 2016 Indiana Warbirds Alliance 7 event tour for 2016. CARDS has hosted this event for the last 4 years and it has been a huge hit each time. The Warbird & Classics Alliance is a group of giant scale r/c warbird and classics events. All share a common goal, to KEEP AVIATION HISTORY ALIVE. They support the radio control industry and promote the growth of warbird and classic flying events. More info can be foundHERE

Unique Aircraft

Not only did we see lots of commonly modeled airframes, but we also had a chance to check out several models that you just don’t see at many events. These modelers have some real talent and spend hours on there airframes getting the “just right” touches in place.

Volunteers

CARDS had no shortage of Volunteers to make sure that this years event ran smoothly. Every thing from parking, to concessions, to flight line management, to just answering questions. They also took the time each day right after the noon demos to open the pit up for people to come get a closer look at these awesome aircraft!

Awards

The winners of this years awards where, Nole Hunt with his SPAD for Best WW1 Aircraft, Jon Seese with his Stuka for Best WW2 Aircraft, Andy Low with his 1/3 Cub for Best Classic Aircraft, Jim Gebboney with his Tiger Cat for Best Multi-Engine, Jack Kezilian with his BAE Hawk for Best Jet, and Al Ferguson with his Newport for Best Realistic Flight. Congrats to all the winners! It was well deserved!

In Closing

In closing I would have to say the the CARDS Club WarBirds and Classics Over Michigan R/C Airshow is absolutely “Must See R/C”! It is not only a great event for pilots to come out and enjoy a fun filled weekend of flying and friendship but is also a great place to bring the family for a cheap day of family friendly entertainment! If your ever in the area during the event its a stop you will want to make! Thanks for coming to check it out with me! See you next time! “Mean Joe V” for FlyingGiants.com!            Credits:

  Matt Gunnhttp://www.flyinggiants.com/CARDS

Joe Vermillion http://  Shop Amazon – All-New Fire TV, Now with 4K

Flying Toy and Hobby RC Helicopters

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In the RC hobby, flying RC helicopters is often considered the hardest RC skill to master. This might make the marketing claims for easy-to-fly toy RC helicopters hard to understand. The difference is in the helicopter design, the controls, and the range of movement that the helicopter is capable of performing.

Hobby-grade RC helicopters are designed to look and operate very much like full-size helicopters.

Toy-grade helicopters are configured and operate a little differently. They are designed for more stable flight so that children can more easily use the transmitter and control the flight. These changes mean that the helicopter is not capable of the same speed or maneuvers as hobby-grade helicopters.Both can still be fun to fly.                                                  

Controlling RC Helicopters

What you can do with an RC helicopter (such as going up and down) are actions initiated by radio signals from the transmitter. The number of channels on a transmitter tells you the number of actions that you can control on the RC.

These actions usually involve things like changing the pitch (tilt) of the rotor blades or making the blades spin faster. A hobby-grade RC helicopter normally requires at least four or five channels for normal flight that closely mimics the controls and flight of full-size helicopters.Toy-grade helicopters may have only 2 or 3 channels and much more limited actions.

Flying Toy RC Helicopters

The typical toy heli is a 2- or 3-channel model that can fly up and down, maybe forward and sometimes backward, and go left and right. It may run at a constant speed. It can hover in place but it’s probably not going to be able to do high speed chases, loops and rolls, or inverted flight.

In order to provide more stable flight, the tail may not have the familiar tail rotor and blades of real helicopters that are set perpendicular to the main rotor.                                        

Instead they often have fixed pitch, counter-rotating dual main rotors (ringed for safety). These rotors eliminate the need for the operator to use tail rotor controls to counteract a natural phenomenum of helicopter flight that makes the body of the helicopter want to spin around and around.

Because the main rotors are fixed pitch (blades don’t tilt independently), there are no cyclic controls — tilting of the main rotor — for climbing and diving or doing banking turns. Instead, the dual main rotors provide level turning. Some models have a small rotor on the tail (parallel to the main rotors) or vertical rotors in other locations that control forward flight and provides further stability.

These design changes sacrifice some of the maneuverability found in hobby-grade helicopters but it also means that the pilot needs to perform fewer actions to keep the helicopter in flight. Simpler controls, slower speed, and less aerobatics ability makes these toy helicopters easier to fly and provide children and novice pilots with more entertainment value. It doesn’t mean that you can master RC helicopter flight right out of the package though. Even with the toy helis it takes patience and practice to hover, fly around the room, and land upright.

For a step up from toy helicopters but with the stability features that make for easier flight, consider a hobby-grade Blade CX. It provides easier hovering and control but has the advanced features of hobby helicopters.

Flying Hobby RC Helicopters

With hobby-grade RC helicopters there are many more actions that the pilot can do and needs to perform to keep the helicopter aloft. Variable pitch rotors and other design features allow the helicopters to do more diving, climbing, rolls, and loops in addition to going up and down and hovering. These actions along with adjustable speed make hobby helicopters extremely challenging to fly but also more exciting.

Transmitters for hobby RC helicopters may come with many channels to control basic helicopter functions, provide more precise control of mixed actions, and change settings on the helicopter from a distance; but, for basic flight four or five channels is normal.         cameracopter

All four or five channels are activated with just the two sticks on the transmitter. The movements typically controlled by a 5-channel transmitter are:

 

Quadcopter: 3 Things you Need to Know

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Helicopters, Drones, Airplanes, Quadcopters? What does it all mean? This week we’re clearing the confusion on the very popular quadcopter. This has got to be one of the newest, trendiest, and most popular kinds of drone for sale. If you’re interested, we’ll bring you three things you must know about quadcopters.

First things first, what the heck is a quadcopter?

No need for confusion here, a quadcopter is simply an “unmanned helicopter having four motors.” Most hobby sites, like ours, also use the term to refer to any RC Drone with four motors. Want the breakdown on all other types of multicopters? Heres the list:

Helicopter: 1 motor                                                                                                                                                       copter35                                       Bicopter: 2 motors        copter36 Tricopter: 3 motors copter37  Quadcopter: 4 motors drone13 Pentacopter: 5 motors drone14 Hexacopters: 6 motors drone15 Octocopter: 8 motors drone16

The multicopter phenomenon currently ends with a Drone/Helicopter with 8 motors (which is plenty).

What you need to know if you purchase a quadcopter:

Well, first off, congratulations on your new quadcopter! We sincerely hope you enjoy it. Just like becoming a new driver, you’ll need to know a few things before you fly your drone.

1. Drone Registration: It is a mandatory thing to do for all drones weighing .55 pounds and less than 55 pounds must be registered to the FAA. Don’t worry, it won’t cost you much, but you must do it before flying your drone.

2. Locate your Power Switch: Sorry if we sound like Captain Obvious here, but you’d be surprised, sometimes it is hard to find this tiny switch. Once you do find it, turn your quadcopter on to see if it had any charge. Test your controller by pressing buttons to make sure that your quadcopter and remote are in sync. If there is no signal, refer to your owners manual to sync both of your devices.

3. Charge Time:  All quadcopters are different, but knowing your quadcopter’s charge time is very important. Find out the time LIMIT. Do not exceed your charging limit because you WILL burn out your battery and have to purchase a new one.

4. Flight time: The more money you spend on your quadcopter, the longer you’ll be in the air. When a quadcopter is about to die, it will simply fall from whatever height it is at. If you know your flight time, you can estimate at what time you should bring your quadcopter down to a shorter height as to not cause damage.

5. Range of Flight: How far does your quadcopter go? Know your range of flight so you can always be in control. For all quadcopters, there is a 400 foot height restriction to prevent interference with Aircraft.

6. Short list of general rules to know:

– Avoid flying in residential or highly populated areas. Not all people are comfortable with quadcopters, and if you lose control, you could crash into someone.

– Keep your drone within eyesight at all times.

– Check your local laws to see if there are any restrictions on where you can or cannot fly your quadcopter.

How to fly your quadcopter:

Now that you know the lingo and the rules, here’s how to get your quadcopter in the air.

Before you fly, check everything off this list:

  • -Remote battery is charged
  • -Quadcopter battery is charged
  • -Micro SD card is in place if there is a camera option
  • -Make sure all pieces of your quadcopter are secure
  • -Pick a flight location with a soft landing and no crowd
  • -Make sure there is no wind or rain to cause flight problems
  • -Be sure you can maintain a direct line of sight at all times with your quadcopter

Learn the lingo of your Transmitter:If you ever need to refer back to your manual for additional instructions, there will be certain terminology to understand in order to use your controller.                         drone17

Roll: Action of pushing the right stick to the left or right. This will “roll” your quadcopter diagonally to the left or right.

Pitch: Action of pushing the right stick forwards or backwards. This will tilt the quadcopter to move forward or backwards.

Yaw: Action of pushing the left stick to the left or right. This will help you change directions while in flight.

Throttle: Action of pushing the left stick forward. This will adjust the height or altitude of your quadcopter. This is the action you will need to use to get your quadcopter off the ground.

Trim: Buttons that will help you increase or decrease the sensitivity of the roll, pitch, yaw, and throttle.

Getting off the ground: All you need is throttle. Use your left stick to put your drone in the air. Make sure you move your left stick smoothly and slowly to achieve more height. Slowly release your left stick to gently place your quadcopter back on the ground.

Once you feel comfortable with flying up and down, try out the rest of your remote functions. One by one, add throttle and yaw, throttle and roll, and throttle and pitch. Moving between all of these functions will get you more comfortable with flying your quadcopter.                                                                                   Credits: http://www.hobbytron.com/blog/   http://   

Rescue 17 Fireboat

Elevating Action on the Water

fire1

There are those products that come to market that get you all riled up as if you were a kid again and what you see on these pages is sure to get you going. As a kid, who didn’t want a sailboat that set off for unexplored lands while you played on the beach? And who didn’t want a plastic boat that braved the rapids of that stream behind your house? Well for big kids into boats, there is a new release that will blow away the wildest inner child’s imagination. The new Aquacraft Rescue 17 Fireboat is the first model boat I’ve ever reviewed with an “interactive” feature, a rotating water cannon capable of shooting a stream of water 10 to 12 feet. It also has lights and a powerful brushless system to propel it to other boats in peril. This boat is sure to get that inner kid in you excited to brave the water as a scaled-down fireboat captain.   Let’s Get the Rescue 17 out of the Box
The Rescue 17 arrived in a big shipping box. With an overall length of 38 inches, a large shipping box is required to protect the model. I was impressed by the packaging technique utilized to secure and protect the hull and cabin structure. There’s a considerable amount of packaging engineering required to create the foam padding encasing the hull to prevent damage during shipping. Although I had seen photos of the Rescue 17 on the inside cover of RC BOAT, Volume 4 and the AquaCraft website, I was still very impressed with the attention to scale detail on the hull and cabin structure. The Rescue 17’s amazing amount of detail adds to the realism. The old axiom, “A picture is worth a thousand words,” will provide a visual listing of the scale detailing.                                                                                                                              fire2

Getting Ready to Put out the Fire
There only a couple of things that need to be done to the Rescue 17 to prepare for operation. The light mast is secured to the top of the cabin with the .15 x 16 screw provided. A dab of CA glue applied to the bottom peg of the antenna will hold it to the light mast. Two “AA” batteries, not provided, are installed in the battery holder inside the cabin to power the light mast. The plug between the battery pack and on/off switch needs connecting. The Tactic TTX 490 4-channel radio requires four “AA” batteries that are also not provided.

Propulsion for the Rescue 17 is provided by an AquaCraft 600 brushed motor powered by a 2200 – 3300 mAh 3S LiPo battery pack. There’s plenty of space in the boat to use a 3S pack with a even a higher mAh rating. The AquaCraft Multi-Controller ESC provides both forward and reverse. Reverse speed is probably around 25 percent of top speed in forward.

It is highly recommended that the pump be primed prior to using the water cannon. There is a direction sheet describing how to prime the pump. This procedure involves removing the water line from the intake tube to the pump, submerging the line in water, and then reattaching the water line. I primed the pump using a fuel bulb filled with water and connected to the intake tube. Squeeze the bulb till water shoots out of the water cannon and the pump is primed. A two-ounce Sullivan Brand fuel bulb is a common hobby shop item. It would also be possible to adapt a cooking baster bulb to shoot water into the pump.                                                                                                                                                                              fire3 Putting out the Fire and/or Candles
Before heading out to run the Rescue 17, I dropped by the local Walgreens to pick up some candles. I have run nitro, gas, electric and sail boat model models over the past 50 years, but the Rescue 17 is the first time I’ve ever operated a model boat capable of extinguishing a fire. Granted, four candles on a piece of foam don’t provide a blazing fire. The candles did, however, provide sufficient flame to test my mini firefighting skills. I quickly discovered attempting to hit the candles with the water cannon wasn’t all that easy. Hitting the candles with the stream of water involved positioning the Rescue 17 the correct distance from the candles, using rudder and speed control and rotating the water cannon to spray across the candles. Racing a 60 mph hydroplane involves less coordination of transmitter inputs than attempting to keep the stream of water from the water cannon on the candles. The slightest amount of breeze greatly influences the positioning of the boat and the direction of the stream of water.                                                  At full throttle, the Rescue 17 moves across the water on plane with a great-looking bow wake. It is capable of making tight corners in either direction. However, sweeping corners would be more in keeping with scale operation of a fire boat. Run time with a 2200 mAh 3S LiPo pack was 12 – 15 minutes, running at full speed. Longer run times would be available if the Rescue 17 was stationary or operated slowly while attempting to extinguish candles.                                                                                                                     fire4After Run Maintenance
A maintenance step not included in the instruction manual was greasing the driveshaft. After approximately one hour of running the Rescue 17, I removed the driveshaft and it needed to have grease applied. It is necessary to remove the rudder to allow removal of the prop shaft. A 1.5mm set screw wrench is required to loosen the set screws on the rudder control arm and shaft coupler. A thin coating of Grim Racer Speed Grease Drive Cable Lube was applied to both the driveshaft and rudder shaft. Wipe any excess grease from the end of the prop shaft to avoid splattering grease on the hull bottom. It was necessary to push the driveshaft slightly downward to insert the shaft back into the coupler. Make certain the flat area on the shaft matches the coupler set screw.                                                                          fire5

Aftermarket Siren from RAM Models
After numerous trips to the lake with my Rescue 17, it seemed like there was something missing from the experience. That missing something was a siren. Having spent time at hobby shows with Ralph Warner, owner of RAM Radio Control Models, I knew Ralph had a siren in his electronics products inventory. Anytime I call Ralph, I know I’m in for a well-deserved, good natured ribbing. Over the years, Ralph has been very generous, providing me with various items his company sells for the RC aircraft, boat, and car enthusiast. Just a few days after our conversation the RAM Mark II Siren arrived in the mail.

The siren kit consists of a circuit board, on/off micro switch, cardboard material for a speaker box, a 1.5-inch speaker, and directions with diagrams. The only assembly required is constructing the speaker box and gluing the speaker to the box. I painted the box black and attached Velcro to the top. Velcro was also applied to the top of the cabin in back of the middle window. The plastic window was removed to allow the sound to exit the cabin. The on/off micro switch is mounted to a separate servo with double back tape. A Y-harness plugged into the throttle section of the receiver actuates the servo when throttle is applied. I spliced a connector into the wires leading to the speaker which allowed the cabin to be removed without having to remove the speaker.                                                                                                                      fire6

The siren definitely adds realism when the Rescue 17 is in operation. The RAM Mark II Siren is available from RAM Radio Control Models, RamRCandRamTrack.com, or you can give Ralph a call at (847) 740-8726.

The Last Word
The Rescue 17 is a model boat an entire family could enjoy operating. My wife, Maren, ran the boat for the photo shoot. Maren’s attempt to extinguish the candles proved rather challenging. Steering the boat wide open around the lake proved much easier than dousing candles 10 feet off the bow. The Rescue 17 is visually impressive as a static and operational model fire boat and it can provide a feeling of accomplishment when the only thing moving is the water cannon spraying water on candles. The Rescue 17 is proof you don’t have to be going fast to have fun with a model boat.                                                           Credits: http://www.aquacraftmodels.com/http://www.rcboatmag.com/Tony Phalen and Words & photos by Jerry Dunlap   http:// 

 

Barnstormers over Champaign 2014 Videos

 

Published on Aug 28, 2014

Taken at the “Barnstormers Over Champaign” event August 23 and 24, 2014. An event I went to on a whim, but next year it will be intentional. Everyone there was friendly and hospitable and made me feel like I was one of the family. If you like radio controlled flying, I strongly recommend that you make it a point to go to the event.                                                                                                                                                plane20

plane21

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http://  Credits: Scott Coyle and http://www.ccrcc.info/main/index.php?option=com_frontpage&Itemid=1  

Joining the Quad Squad: How To Get Started with RC Quadcopters

Want to shoot your own GoPro videos from high vantage points and other places you can’t normally reach? You may want to mount one on a quadcopter. Getting started isn’t difficult, but you’ll benefit from our recommendations and tips for beginners. Welcome to the world of multi-rotor RC aircraft.                                                                                                                                                                                                                                                                             A cursory search on YouTube or Vimeo will yield a bountiful selection of footage captured from radio-controlled (RC) model aircraft known as multi-rotors. The name comes from the fact that these particular models rely solely on horizontal propellers (rotors) to provide lift and directional control. Most multi-rotors have four propellers, so they are called “quad-rotors”, or just “quads”. For the sake of simplicity in this article, I’ll brand all multi-rotors as “quads”, while recognizing that there are versions with three to eight airscrews…sometimes more.                                                                                                      drone3

Despite their unaerodynamic appearance, quads are ideal for capturing photographs and video footage from the sky. Many of them can heft a surprisingly heavy payload (i.e. good quality imaging equipment) and hold a steady posture in the air. With the ability to hover in place and fly in confined spaces, quads can often provide perspectives that no other filming technique can mimic. Watch some of those YouTubevideos and you’ll see what I mean. Not only that, but quads are fun to fly with or without a camera attached.

But before you zip out and buy a quad of your own, there is one more thing you should know. Switch over to a news site and it won’t take a lot of digging around to find the unglamorous B-side of quads. How about the wedding photographer who flew his camera-toting quad into the bride and groom? Then there is the wise guy who took his quad over Manhattan, only to crash into the side of a high rise, where his machine plummeted to the sidewalk 300 feet below. Let’s not forget the genius who flew his quad so high and so near JFK airport that it was spotted by a passing (and quite perturbed) airline captain! This unfortunate list goes on and on, yet the takeaway is but twofold:

  • Multi-rotor models are capable of inflicting surprising amounts of injury and/or damage…think “flying Cuisinart”.
  • Multi-rotor models require diligence and practiced skill to fly competently…think “unicycle”.             drone4If you’re still reading, I assume that you have some aspiration of owning a quad and perhaps racking up those YouTube views. That goal is reasonable and attainable even if you’ve never operated a RC vehicle before. Just recognize that diving into multi-rotors without heeding the lessons above could render you the next bungler featured on the evening news. Not to mention that doing something with your quad that captures the attention of CNN is also likely to attract the attention of local police, the FAA, and quite possibly the FBI…and that’s no joke. My point is not to discourage you from buying a quad, but to inform you of the aspects of quad ownership that are often unintuitive.Let’s get started!

    Anatomy of a Multi-Rotor                                                                                                                          drone5

    As with any RC vehicle, there are two basic components to deal with: the transmitter and the vehicle itself. The transmitter is the device you hold to provide control inputs. A quad transmitter is the standard two-joystick box that is also used for RC airplanes and helicopters. Moving the left joystick up or down changes the power setting on all four motors and makes the quad climb, descend, or maintain altitude. Moving the left joystick to the left or right causes the quad to yaw in that direction (i.e., it pivots about an imaginary vertical axis through the center of the vehicle). The right joystick controls pitch and roll. Simply put, whatever direction you move the right joystick will command the quad to tilt and translate in that direction.

    Most quads are arranged in an X configuration (when looking from above) with a motor/propeller at each corner. A rechargeable lithium polymer battery provides power for the motors and the electronic equipment onboard the quad. As a beginner, it isn’t really necessary to understand the function of all of a quad’s electronics. Those lessons will come as you progress in the hobby. For now, you just need to understand that the four motors work in unison, at different speeds, to keep a quad hovering and maneuvering through the air.                                                                                          drone6

    I’m Learning To Fly, But I Ain’t Got Wings

    One aspect of RC flight that many beginners have trouble with is the light touch that most quads and other RC aircraft demand. The overwhelming tendency of beginning pilots is to over-control and then overcorrect. The result is a herky-jerky flight path that that may or may not end well for the quad. Watching videos from these types of flights can make you turn green with nausea.

    Fly with a light touch. The overwhelming tendency of beginning pilots is to over-control and then overcorrect.

    Another hurdle for beginning pilots is overcoming the perspective of being outside the model. When the quad is in front of, and facing away from you, everything seems normal. Right is right, and forward is forward. When the nose of the quad is pointing towards you, however, the perspective changes. Now, when you command the quad to tilt to the right, you will see it tilt to your left. When you command it to tilt rearwards, it will move away from you. The quad is still responding to your commands the same way. It’s just that the quad’s right/left and front/back are no longer the same as yours.

    Perhaps the hardest thing about flying a quad is simply keeping track of which end is which. Quads lack the wings, tail surfaces, and other visual cues that you are used to seeing on airplanes and helicopters. So, it is often difficult to know which way the quad is pointed. Such disorientation leads to erroneous control inputs. Commanding a zig, when you meant to zag is the root cause of many crashes.

    While the challenges of becoming a competent quad pilot may seem daunting, I have yet to meet anyone that didn’t eventually get the hang of it. Most catch on rather quickly…especially kids. Mastering the necessary skills is simply a matter of getting some flight time under your belt and learning from your mistakes. And yes, that also means occasionally making repairs to your quad after an especially ham-fisted or harebrained flight.

    Where To Start

    Logging flight time does not mean that you have to put an expensive, camera-ready quad at the mercy of your fledgling skills. That would be like learning to juggle using flaming Ginsu knives or moody honey badgers. There are a couple of more sensible alternatives. One option is to get a RC flight simulator for your PC. The one I use is RealFlight 6.5, which includes a quad in its stock database of flying models. Just as important, RealFlight includes a USB controller with the same look and feel as a RC transmitter. This helps to make the transition from virtual flight to genuine flying pretty seamless.                                                                                                                                       drone7

    REALFLIGHT SOFTWARE IS GOOD FOR PRACTICE.

    One great thing about a software simulator is that it also lets you try your hand at RC airplanes and helicopters of all skills levels. It is really remarkable how broad the performance spectrum is for different models. Plus, no matter how badly you mangle the quad, airplane or helicopter on the screen, pressing the reset button will instantly make it as good as new!

    Another way to learn quad flight is to purchase a micro quad. These are small (about 5”x 5”) quads that look and behave the same way that larger quads do. They are really amazing little machines. The advantage of learning with a micro quad is that they have such low mass and so little power driving their tiny propellers that they are very unlikely to cause any harm when you smack them into something (and you will).                                                                                                                 drone8

    My first quad was the 1SQ from Heli-Max. It is a “hobby grade” micro quad, as opposed to “toy grade”. This means that you can buy spare parts and keep it going if you somehow find a way to damage it. My 1SQ absorbed quite a bit of abuse as I learned the basics of quads, and it is still going strong with nothing more than replacement propellers.

    Buying a micro quad with a gamepad-like transmitter or one that is controlled by an iphone won’t really help you transition to larger, more capable quads.

    eBay is flooded with all types of micro quads. Some appear to be genuine, while others are obvious knock-offs of popular hobby-grade quads. Then, there are other quads of even more questionable pedigree. Honestly, I don’t know how to tell the good eBay finds from the bad. My recommendation is to spend a few more bucks and buy a micro-quad from your local hobby shop. If you decide to go the eBay (or similar) route, at least make sure that the micro-quad you choose includes a 2-stick transmitter. Buying a micro quad with a gamepad-like transmitter or one that is controlled by an iphone won’t really help you transition to larger, more capable quads.

    A neat thing about micro quads is that you can fly them indoors. Foul weather and darkness need not impede your training. As I said, you will bump into things as you learn (and beyond). So be sensible and stay away from pets, kids, the plasma screen, Aunt Edith’s urn…you get the idea. And for Pete’s sake, turn off the ceiling fan! Other than exercising those precautions, there is little to worry about. As your piloting skills progress, you can challenge yourself to increasingly difficult tasks. You may start out just trying to land on the coffee table. In time, you’ll be dusting your ceramic frog collection with the micro quad’s rotor wash.                                                                            drone9

    Stepping Up

    Once you feel that you have the hang of quad flying, it’s time to upgrade to something capable of carrying a high quality camera. It is worth mentioning that there are some micro quads with integrated cameras (including the V-Cam version of the 1SQ). These quads are also a lot of fun and you can get some good experience tackling the challenges of filming without the benefit of a viewfinder. Just don’t expect the image quality to meet the level that we’ve become accustomed to from GoPro and similar cameras.

    Beyond micro quads, there is a lot of room to grow in terms of cost and capabilities, but let’s focus on the next logical step. The DJI Phantom is a very popular quad that is capable of carrying a GoPro camera. The Phantom includes all of the things that you want in an intermediate quad: attitude stabilization, brushless motors, a GPS unit, a built-in GoPro mount, etc. What has made the Phantom so popular is that all of these components come preconfigured and integrated as a flight-ready system. You can bring home a Phantom and have it flying in the time it takes to charge the included battery (about an hour).                                                                                                              drone10

    If you choose to buy a Phantom, I think you will agree that it is considerably easier to fly than a micro quad. I’ve found the Phantom’s stabilization and position-holding ability to be rock solid. I can park it in the sky and take my hands off of the joysticks. Even if there is a light breeze, the Phantom will stay in place until I command it to go somewhere else.

    Unlike micro quads, the Phantom has enough mass and horsepower to cause grief when you hit something with it. The conscientious world citizen in you should want no part in causing a dent in a car, or maybe buying stitches for a stranger. The savvy economist in you should never forget that you don’t want to squander the nearly $1000 tied up in a Phantom with the latest GoPro by crashing it into a lake. Play it safe on both counts with your first flights and find a nice open space devoid of other people. You will appreciate the elbow room until you get comfortable flying the Phantom. Even later, you should always ask yourself “Is it safe to fly here?”

    Some makers will shun the turnkey approach afforded by the Phantom, since it’s an all-in-one package that works out of the box. Fortunately, DJI and other companies offer many quads in kit form. This lets you choose the components you want and customize the quad to your liking. Taking the DIY route also provides you with an intimate knowledge of how the different components of a quad work in unison to achieve controlled flight.

    What’s Next?

    You may find that a Phantom/GoPro combo is all that you need to satisfy your aerial photography ambitions. For many fliers, however, this stage is a gateway to more capable set-ups. One popular upgrade is to add a First Person View (FPV) system. FPV provides a real-time video downlink from the quad. When you connect that downlink to a portable screen or video goggles, you get the same bird’s eye view as the onboard camera…neat stuff for sure. FPV systems are often coupled with a two-axis gimbal that lets you pan and tilt the camera during flight. Just be aware that most FPV systems require a HAM Technician license to operate legally.                                                                    drone11

    GEAR FOR FPV FLYING.

    GoPro Heroes are awesome little cameras that will serve you well. If, however, you yearn to carry higher end video equipment, there is probably a multi-rotor to fit the bill. The cost and complexity of these aircraft climb accordingly. Most of the larger multi-rotors have six or eight motors. Some of these units can run several thousand dollars (without video equipment). It’s a matter of balancing your budget and skills with the image quality that you aim to achieve.

    Finding Solidarity and Community

    With the ever-growing popularity of quads, there’s no reason to jump in to the hobby alone. Unless you live way out in the boonies, there is probably an established quad flyer not too far away. Search for RC clubs and hobby shops in your area to get started. Most RCers are happy to share their knowledge and experience. There are also numerous online forums that discuss all aspects of quads and other RC endeavors. My favorite is RCGroups.com. The only problem with online forums is filtering out the genuine good advice from the well-meaning misinformation of self-proclaimed experts. With a little lurking, you can usually pick out who the trustworthy members are.

    You should also consider joining the Academy of Model Aeronautics (AMA), which is a national organization that provides a united voice for all types of aeromodelers. In fact, AMA membership is a prerequisite for joining most local RC clubs. Among other things, the $58 annual dues provide an insurance policy for you and help the AMA in its efforts to protect modelers from unnecessary regulations. This is especially important now, as the FAA is considering folding model aircraft operations into its jurisdiction.

    Get Going!

    This beginner’s guide is admittedly light on technical information. There will be plenty of time for that stuff once you’re ready to buy a quad of your own. I hope, however, that the roadmap presented here will help you to avoid some of the common mistakes and misconceptions of budding multi-rotor pilots. Flying quads is a lot of fun, and shooting videos only sweetens the deal. It just takes a little bit of training and situational awareness to be successful. Now go have fun and make a video worthy of awards, not the news! Credits: TERRY DUNN  http://www.tested.com/  http:// http://

     

     

The Hull of Fame – Fast Electric

In over a decade of my Radio Control Boating experience, I have come in contact with many different Fast Electric boats. I can remember the days of charging up my NiCD packs in anticipation of a solid day of boating. Then one day there were an overwhelming amount of people switching to the newer NiMh battery technology. NiMh proved as a solid performer for many years to come. Then to every RC maniacs dreams, LiPo’s were born. This technology in batteries have given RC in general one of the biggest uproar. It allowed a much greater overall power system to be used in any RC imaginable.

Now in the boating community this was very big news. Boats take a tremendous amount of power to drive them at speeds that a typical RC car would travel at. This need for extreme power was the result of intense amounts of drag for any object moving through water. This shouldn’t come as  a surprise, when was the last time you changed your disk brakes on a boat? Yep boats don’t have brakes, it feels as if they have permanent anchors.

Before the battery technology and brushless technology that we currently have today, it was difficult to get a Ready to Run boat that traveled faster then 40 km/h. In most cases, when you did have a boat that was in that range of speed, it had to have 2 brushed motors running to the same prop shaft, running off of multiple cells and through an awkward transmission coupling it all together.

It wasn’t until the very first Mainstream boat was introduced that we started seeing some excellent performance numbers that changed the Ready to Run boating market.

The Hull of Fame – Fast Electric

The boat that enters the hull of fame at RadioControlInfo is one that every enthusiast will remember. It was the first mainstream brushless boat that could really benefit from LiPo’s, but many were still using top notch NiMh packs with great success.

Entering the hull of fame is the Aquacraft Supervee 27 RTR.

This Boat sold well before it even hit stores, it was well marketed, well designed, and well built. Many popular features were built in to the boat to ensure that it performed well, we will first start with the hull itself.boat23

Why the Supervee “27” – The Hull of Fame

The Supervee 27 was called the Supervee “27” as the hull length was based around being 27 inches in length. This was an important part of the design as size did matter. A hull under performs if the length is too small, but here’s the catch. The hull also under performs if the boat is sized to long. The under performance changes in each case where a smaller hull will suffer in the handling department and a hull that is sized too large for its power system will suffer in its power and performance department. In order to get this correctly, it takes a precisely selected hull length. boat24

Running Hardware – The Hull of Fame

Blue anodized running hardware was nailed to the back of this hull. The blue colour looks great, and the sizing of each individual component was well determined and affected the handling performance in a very positive way. Now since there’s so many good things about this boat to talk about, let’s hurry up and get over the one issue that this boat suffered from. Water cooling. Yep, that’s it. Now did it matter? Mine ran no problem with the limited amount of water that circulated through the cooling system.  The problem was found to be in the aluminum rudder of this hull and Aquacraft corrected this problem in a later version of this hull. Now that we are over that one hurdle, let’s move in to the power system.                       boat25

Welcome to Brushless Power – The Hull of Fame

Aquacraft dropped in the best power plant that a high volume RTR hull has seen in all of fast electric boating history,  making every father shake in his shoes while driving one of these.  Pop open the cowl on this boat and you will find a 3/4 horsepower electric motor. It isn’t just any motor, it’s a brushless motor.  Brushless motors at the time were relatively new to people and the 3 wires coming out of the can on this motor would confuse many people. I remember the countless threads titled ” which motor wire connects to which ESC wire?” This just goes to show the lack of experience in brushless motors in that particular time. Not many people seen them in boats before, especially RTR boats.                                                           boat26

Electronic Speed Control – The Hull of Fame

The component responsible for delivering battery power to the motor was an ESC (Electronic Speed Control) that was still designed around NiMh batteries. The only reason one could not use LiPo’s was because of the lack for an appropriate low voltage cutoff built in to the ESC. If you wanted to run the boat on LiPo’s you would simply have to time your run and bring the hull in after a certain time period or purchase a 3rd party device that would incorporate a lower voltage cutoff. Timing your run is something that I talk about a lot in the build a fast electric boat part of the website, and is something that every boater should be doing in good practice. When performed correctly this is a guaranteed way of preventing any over discharging of the batteries.                                                                                                    boat27

Putting it all together – The Hull of Fame

When putting it all together, this hull sold for approximately 300 USD. At this price point it was a very good deal, especially for something this advanced in the boating market. No other Mass produced radio control boat had all of these features combined in to one solid package.

What did you get in terms of performance? Well, quite  a handful. The handling characteristics of this 27 inch long hull was very good considering the speed you could achieve. Among many things, cornering felt smooth and predictable. Tight turning radius’ were possible at 70% speed which offered excellent control. This however was only possible during a right hand turn. Due to the nature of racing, our RC models at a race circuit will only make right hand turns and keeping this consistent, the Supervee 27 was only fitted with a right hand turn fin which did not allow for aggressive left hand turning performance. The overall speed of this boat heavily outweighed this small minute obstacle.  With 64km/h speeds possible, this boat was a handful. Even with NiMh packs, maintaining over 55km/h was entirely possible.

Paving the Road in to the Future – The Hull of Fame

Aquacraft Models whether they knew it or not paved the road for companies to jump on board the Ready to Run High performance Radio Control boating market. Looking at what we have available now is surely different in terms of variety then it was just 7 or so years ago.  Someone had to break the ice and it did not take long until there were Supervee’s buzzing around the lakes and ponds right after that ice starts to separate.                                                                                                                                                                         Credits:  Ryan http://www.radiocontrolinfo.com/   http://

Detailed RC Loaders, Cranes And Trucks Move Dirt In Their Own Mini World at Intermat (VIDEO)

Throughout the Intermat trade show in Paris , the first pieces of yellow iron attendees saw as they entered the earthmoving pavilion were a bit on the small side. Situated just before the entrance of Hall 5 was a whole city of where remote-controlled scale model construction equipment were free to move and haul to their hearts’ content. We’ve put together a gallery of the mini machines above. The loaders and cranes were especially impressive in person. And in the video below, you can check out a few of the machines in action. And be sure to stick around for the “Final Countdown” at the end. equip1 equip2 equip3 equip4 equip5 equip6 eqip7 equip8 equip9 equip10 equip11 equip12equip13 equip14 

Credits: http://www.equipmentworld.com/    

RC General Buying Decisions

veh1Radio controlled vehicles/craft can be fairly cleanly divided into two categories, toy and hobby-level. The toy type are what most people think of when you mention “RC” — buy-and-drive playthings that you can purchase from a toy or electronics store. These are made strictly for the sake of fun. Then there are the more sophisticated and capable models targeted towards hobbyists who want to go faster, tinker with settings and upgrades, and perhaps participate in one of the many levels of established competitive events. Neither class of RC is necessarily “better” — they each have their positive and negative qualities. However, when you’re first starting out, it’s very worthwhile to choose which way you want to go up front, long before you pull out your credit card. This article presents the most important facts that can help you make an informed decision.                                                                                                                                            

Cost

Toy R/C cars & trucks that you can buy at places like Toys R Us or Walmart start at $20-25 USD, and the most extreme ones top out around $150. Toy R/C planes start at around $30. When you step up to the hobby level, you’ll be hard pressed to find something complete for under $130. It’s very easy to spend $400-500 on a 1/10th scale car or truck that will last awhile, and a fully upgraded rig can easily shoot up to $2,000-3,000 USD.

Speed

In most cases, there’s really no comparison between the performance of toy and hobby-level RCs. Most toy cars & trucks will go anywhere from 5mph to 15mph, with the fastest few doing 20-24mph. Hobby-level RCs generally start at 15-25mph for electrics and 25-35mph for nitro versions. You can get monster trucks that will do over 40mph out of the box, and low-slung street cars that will do over 60 with no upgrades or modifications. In planes, the toys generally go around 5-15mph, while there are hobby-class craft that will do 30, 50, even 80mph in factory stock form. The most extreme speed differences are in boats. The toys often putt and crawl along at 1-5mph, while the hottest hobby-level racing boats will skim the surface at over 100mph

Durability

Mostly because they’re slow, toy RCs tend to handle more abuse than their more expensive cousins. The most common things to break are bumpers and body trim. The land and water-borne vehicles are built with a lot more material than is necessary, while aircraft tend to be constructed of foam and flexible plastics that bounce back after being bent. However…

When they break…

Repairing a toy RC is sometimes not worth the time & effort. Nearly all use multifunction circuit boards that combine several major functions, so if something goes electrically wrong, you have to change out the whole thing. Most manufacturers don’t have a factory service program, so you have to do the work yourself. Many don’t even offer a way to order new parts. Nikko is a notable exception. You can call them, tell them exactly what vehicle you have, describe the problem, and order precisely the part(s) you need. Many RC’s available at Radio Shack are actually from Nikko and are covered by this same level of support, with the additional convenience of being able to go back to the store and special-order your parts in person.

Fixing hobby-level RCs is, in most cases, a completely different affair. You can disassemble anything yourself. With most popular brands there are manuals and exploded views. There are service departments that handle returns of defective components. Electronics are, with rare exception, separated by function so that you don’t have to change your speed controller if your radio receiver crystal goes bad. Parts are available at brick-and-mortar hobby shops and dozens of trusted, popular web sites. There are online forums (message boards) where you can ask other hobbyists for advice and learn from their experience. veh2

Upgradability

These days, ever more toy RCs have upgrades available for purchase from the original manufacturer, particularly amongst the smaller “micro” cars and trucks. These upgrades can range from different body kits to stickier tires to faster motors. They’re generally very easy to install, requiring at most a small screwdriver (which is often included) and 15 minutes, and can dramatically change the look or performance of the vehicle. They’re also great fun to install and let the owner add a bit of their own personality.

The most popular hobby RCs may have literally hundreds of upgrades available from many different aftermarket sources (companies other than the original manufacturer). Among the available upgrades may be anything from scale-realistic wheels to anodized aluminum struts in various colors to larger motors/engines to total conversion kits that fundamentally change the vehicle. Many hobby-level RC parts are reusable from one vehicle to another, especially electronic components and motors/engines. Popular RC models come with the support of other owners nationwide or around the world who share their experiences, tips, and home-grown modifications freely on the Internet.

Controllability

Toy radio systems traditionally give you forward/reverse (or up/down) and left/right direction control. A growing number of cars & trucks these days now have “digital proportional” steering to boot, which gives you a number of steps between neutral and full turning, depending upon how far you turn the wheel or push the stick on the radio transmitter. Some, though, only let you go straight forward or to turn one pre-set direction in reverse. Toy helicopters are what you have to watch out for the most, as these sometimes give you only one axis of control — go straight up, or come straight down. Most toy RC’s are still only available on two frequencies (e.g., 27mhz and 49mhz in the US), with a few now offering 3 to 6 possibilities. This limits the number of vehicles that can run at one time, but more unfortunately it reduces the possibility of even being able to run two random vehicles together.

Hobby-class radio systems give you 64 to 256 (or more) steps of control in each direction for what feels like perfectly smooth turning & throttle control. These systems can also be easily changed between anywhere from 6 to 30 different frequencies, so even if the one person you want to race against or fly with has an absolutely identical radio setup, for around $20 and with a one-minute part swap, you’re both in the clear. Still better, the most recent generation of radio systems, while expensive, operate on an extremely high frequency and use small computer chips to automatically search for and lock onto an open channel, ensuring that you’ll never have a frequency conflict.

Raceability

Toy RCs can be raced between siblings or friends around the neighborhood, but there’s generally no sanctioned racing. Hobby-level RCs are raced around the world in local, regional, national, and even international events, even including multi-track tours.

Ownership

When all is said and done, the purchase decision between toy & hobby-level RCs should always come down to who the purchase is being made for. You don’t want to buy a $390, 45mph nitro-powered car for a 6-year-old. Likewise, a 16-year-old who wants to get into RC racing for sport wouldn’t be well-served by a $39 toy. What’s really interesting is the 26-year-old with a $25 micro-sized monster truck who would derive hours of fun from chasing his/her cat around the kitchen floor or gingerly driving around a makeshift desktop obstacle course during lunchtime at work. Before you buy an RC, know who you’re buying it for and do a little research. That extra time spent up front could make the difference between tremendous fun and awkward disappointment. Credits: http://www.beginningrc.com/ http://

Aerodynamics

  • IntroductionAerodynamics is the study of forces and motion of objects through the air.

     

    Basic knowledge of theaero1
    aerodynamic principles
    is highly recommended
    before getting involved
    in building and/or flying
    model aircraft.
    • A model aircraft that is hanging still in air during strong winds may be subject
      to the same aerodynamic forces as a model aircraft that is flying fast during
      calm weather.
      The aerodynamic forces depend much on the air density.

aero2

  • For example, if a glider glides 25 meters
    from a given altitude during low air density
    it may glide 40 meters during high density.


    The air density depends on the atmospheric pressure and on the air temperature.
    The air density increases with decreasing of the air temperature and/or with
    increasing of the atmospheric pressure.
    The air density decreases with increasing of the air temperature and/or with
    decreasing of the atmospheric pressure.
    A flying aircraft is subject to a pressure depending on the airspeed and the
    air density.
    This pressure increases exponentially with increasing of the airspeed.
    The aircraft’s resistance to the airflow (drag) depends on the shape of the
    fuselage and flying surfaces.
    An aircraft that is intended to fly fast has a thinner and different wing profile
    than one that is intended to fly slower.
    That’s why many aircraft change their wings’ profiles on landing approach
    by lowering the flaps located at the wings’ trailing edge and the slats at the
    leading edge in order to keep enough lifting force during the much lower
    landing speed.

    The wings’ profile of an aircraft is usually asymmetric, which makes the
    pressure on the wings’ upper side lower than the underside, causing the air on
    the wings upper side to accelerate downwards, thereby a lift force is created.

    The air always flows away from areas of higher pressure toward areas of lower
    pressure, thus the air over the wing top accelerates as it enters the lower
    pressure region (where the air curves toward the wing), whereas the air under
    the wing slows down as it enters the higher pressure region.
    So, one may also say that the wings create lift by reacting against the air flow,
    driving it downwards, producing downwash.
    The top of the wing is often the major lift contributor, usually producing twice as
    much lift as the bottom of the wing.

    The lift force of a symmetric profile is based on the airspeed and on a positive
    angle of attack to the airflow, which makes the air react as it was asymmetric.

    The following picture shows the airflow through two wing profiles.

aero3

  • The uppermost profile has a lower angle of attack than the lowest one.
    When the air flows evenly through the surface is called a laminar flow.
    A too high angle of attack causes turbulence on the upper surface, which
    dramatically increases the air resistance (drag), this may cause the flow
    to separate from the upper surface resulting in an abrut reduction in lift,
    known as stall.Summarising:
    The aircraft generates lift by moving through the air.
    The wings have airfoil shaped profiles that create a pressure difference
    between upper and lower wing surfaces, with a high pressure region
    underneath and a low pressure region on top.
    The lift produced will be proportional to the size of the wings, the square
    of airspeed, the density of the surrounding air and the wing’s angle of
    attack to on-coming flow before reaching the stall angle.

    How does a glider generate the velocity needed for flight?
    The simple answer is that a glider trades altitude for velocity.
    It trades the potential energy difference from a higher altitude to a lower
    altitude to produce kinetic energy, which means velocity.
    Gliders are always descending relative to the air in which they are flying.

    How do gliders stay aloft for hours if they constantly descend?
    The gliders are designed to descend very slowly.
    If the pilot can locate a pocket of air that is rising faster than the
    glider is descending, the glider can actually gain altitude, increasing
    its potential energy.

    Pockets of rising air are called updrafts.
    Updrafts are found when the wind blowing at a hill or mountain rises to
    climb over it. (However, there may be a downdraft on the other side!)
    Updrafts can also be found over dark land masses that absorb more
    heat from the sun than light land masses.
    The heat from the ground heats the surrounding air, which causes the
    air to rise. The rising pockets of hot air are called thermals.

    Large gliding birds, such as owls and hawks, are often seen circling
    inside a thermal to gain altitude without flapping their wings.
    Gliders can do exactly the same thing.

aero4                                                                                                            

  • Wing Geometry Definitions
    A vertical cut through the wing parallel to flight’s direction (plan view) will show
    the cross-section of the wing.
    This side view (profile) is called Airfoil, and it has some geometry definitions
    of its own as shown on the picture below.

aero5

      The longest straight line that can be drawn from the Airfoil’s leading edge to
      trailing edge is called the

Chord Line

      .
      The Chord Line cuts the airfoil into an upper surface and a lower surface.
      If we plot the points that lie halfway between the upper and lower surfaces,
      we obtain a curve called the

Mean Camber Line

      .
      For a symmetric airfoil (upper surface the same shape as the lower surface)
      the Mean Camber Line will fall on top of the Chord Line.
      But for an asymmetric airfoil, these are two separate lines. The maximum
      distance between these two lines is called the

Camber

      , which is a measure
      of the curvature of the airfoil (high camber means high curvature).
      Asymmetric airfoils are also known as cambered airfoils.
      The maximum distance between the upper and lower surfaces is called the

Thickness

      .
    Both Thickness and Camber are expressed as a percentage of Chord.

aero6

      Airfoils can come with all kinds of combinations of camber and thickness
      distributions. They are designed for the condictions under which the plane is
      likely to be flown most of the time.
      NACA (the precursor of NASA) established a method of designating classes
      of airfoils and then wind tunnel tested the airfoils in order to provide
      lift coefficients and drag coefficients for designers.

Aspect Ratio

      is a measure of how long and slender a wing is from tip to tip.
      The Aspect Ratio of a wing is defined to be the square of the span divided
      by the wing area and is given the symbol

AR

      .
      The formula is simplified for a rectangular wing, as being the ratio of the span
    to the chord length as shown on the figure below.

aero7

      Wing

Dihedral

      refers to the angle of wing panels as seen in the aircraft’s
      front view.
      Dihedral is added to the wings for roll stability; a wing with some Dihedral
      will naturally return to its original position if it is subject to a briefly slight
      roll displacement.
      Most large airliner wings are designed with Dihedral.
      On the contrary the highly maneuverable fighter planes have no Dihedral.
      In fact, some fighter aircraft have the wing tips lower than the roots, giving
      the aircraft a high roll rate.
    A negative Dihedral angle is called Anhedral.

  • Forces in FlightGravity, Lift, Thrust and Drag.

aero8

  • Gravity is a force that is always directed toward the centre of the earth.
    The magnitude of the force depends on the mass of all the aircraft parts.
    The gravity is also called weight and is distributed throughout the aircraft.
    But we can think of it as collected and acting through a single point called
    the centre of gravity.
    In flight, the aircraft rotates about its centre of gravity, but the direction of the
    weight force always remains toward the centre of the earth.Lift is the force generated in order to overcome the weight, which makes the
    aircraft fly.
    This force is obtained by the motion of the aircraft through the air.

    Factors that affect lift:

aero9

  • Lift force is therefore dependent on the density of the air r, the airspeed V,
    the type of airfoil and on the wing’s area according to the formula below:Lift Force = 0.5 * r * V2 * Wing’s Lift Coefficient * Wing Area

    Where the Lift Force is in Newton, Wing Area in m2 and the airspeed in m/s.
    The standard density of the air is 1.225kg/m3.

    The wing’s lift coefficient is a dimensionless number that depends on the airfoil
    type, the wings aspect ratio (AR), Reynolds Number and is proportional to the
    angle of attack (AoA) before reaching the stall angle.

    Thrust is the force generated by some kind of propulsion system.
    The magnitude of the thrust depends on many factors associated with the
    propulsion system used:

    – type of engine
    – number of engines
    – throttle setting
    – speed

    The direction of the force depends on how the engines are attached to
    the aircraft.

    The glider, however, has no engine to generate thrust. It uses the potential
    energy difference from a higher altitude to a lower altitude to produce kinetic
    energy, which means velocity.
    Gliders are always descending relative to the air in which they are flying.

    Drag is the aerodynamic force that opposes an aircraft’s motion through the air.

    Drag is generated by every part of the aircraft (even the engines).

    There are several sources of drag:

    One of them is the skin friction between the molecules of the air and the
    surface of the aircraft.
    The skin friction causes the air near the wing’s surface to slow down.
    This slowed down layer of air is called the boundary layer.
    The boundary layer builds up thicker when moving from the front of the airfoil
    toward the wing trailing edge.
    Another factor is called the Reynolds effect, which means that the slower we
    fly, the thicker the boundary layer becomes.

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  • Form drag is another source of drag.
    This one depends on the shape of the aircraft.
    As the air flows around the surfaces, the local airspeed and pressure changes.
    The component of the aerodynamic force on the wing that is opposed
    to the motion is the wing’s drag, while the component perpendicular to the
    motion is the wing’s lift.Induced drag is a sort of drag caused by the wing’s generation of lift.
    One cause of this drag is the flow near the wing tips being distorted as a result
    of the pressure difference between the top and the bottom of the wing, which in
    turn results in swirling vortices being formed at the wing tips.
    The induced drag is an indication of the amount of energy lost to the tip vortices.
    The swirling vortices cause downwash near the wing tips, which reduces the
    overall lift coefficient of the wing.

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  • The picture below shows the downwash caused by an aircraft.

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  • The Cessna Citation has just flown through a cloud.
    The downwash from the wing has pushed a trough into the cloud deck.
    The swirling flow from the tip vortices is also evident.The wing geometry (aspect ratio AR) also affects the amount of induced drag:
    Long wing with a small chord (high AR) has low induced drag, whereas a short
    wing with a large chord (low AR) has high-induced drag.
    For the same chord, the wing with a high AR has higher lift coefficient, but stalls
    at lower angle of attack (AoA) than the wing with a low AR.
    Also, aircraft with high AR wings are more sensitive to elevator control.

    The induced drag increases with increasing of the wing’s actual lift coefficient
    being generated and it’s proportional to the square of the angle of attack.
    And since a slower airspeed requires a higher angle of attack (AoA) to produce
    the same lift, the slower the airspeed is, the greater the induced drag will be.
    So, the induced drag is also inversely proportional to the square of the airspeed.

    In order to minimise tip vortices some designers design a special shape for
    the wing tips.
    With drooped or raised wing tips, the vortex is forced further out.

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  • However, this method will cause an increase in weight since they need to be
    added to the wing tip.An easier and lighter method is by cutting the wing tip at 45-degrees.
    With a small radius at the bottom and a relatively sharp top corner, the air from
    the secondary flow travels around the rounded bottom but can’t go around the
    sharp top corner and is pushed outward.

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  • There’s also the Interference drag, which is generated by the mixing of
    streamlines between one or more components, it accounts for 5 to 10%
    of the drag on an airplane.
    It can be reduced by proper fairing and filleting which allows the streamlines
    to meet gradually rather than abruptly.All drag that is not associated with the production of lift is defined as
    Parasitic drag.

    The graph below shows the induced and the parasitic drag versus airspeed.
    Total drag is the induced drag plus the parasitic drag.

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  • Since during constant speed and level flight the thrust is equal to the total drag
    the graph also shows how much thrust is needed at different level flight speeds.At take-off (just above the stall speed), a high AoA is needed to get enough lift
    which increases the total drag and also the thrust needed.
    As the speed increases, the AoA needed to get the same lift decreases and so
    does the total drag until the minimum drag speed is reached, above which the
    total drag starts increasing exponentially (and so does the thrust needed).
    The plane’s max level speed will be limited by the prop’s pitch speed or by the
    max thrust available, which altogether means by the max power available.

 

  • Stability ConceptsThe aircraft’s response to momentary disturbance is associated with its
    inherent degree of stability built in by the designer, in each of the three axes,
    and occurring without any reaction from the pilot.

    There is another condition affecting flight, which is the aircraft’s state of trim
    or equilibrium (where the net sum of all forces equals zero).
    Some aircraft can be trimmed by the pilot to fly ‘hands off’ for straight and
    level flight, for climb or for descent.

    Free flight models generally have to rely on the state of trim built in by the
    designer and adjusted by the rigger, while the remote controlled models have
    some form of trim devices which are adjustable during the flight.

    An aircraft’s stability is expressed in relation to each axis:
    lateral stability (stability in roll), directional stability (stability in yaw)
    and longitudinal stability (stability in pitch).
    Lateral and directional stabilities are inter-dependent.

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  • Stability may be defined as follows:
    – Positive stability: tends to return to original condition after a disturbance.
    – Negative stability: tends to increase the disturbance.
    – Neutral stability: remains at the new condition.
    Static stability: refers to the aircraft’s initial response to a disturbance.
    A statically unstable aircraft will uniformly depart from a condition of equilibrium.

    Dynamic stability: refers to the aircraft’s ability to damp out oscillations, which
    depends on how fast or how slow it responds to a disturbance.
    A dynamically unstable aircraft will (after a disturbance) start oscillating with
    increasing amplitude.
    A dynamically neutrally stable aircraft will continue oscillating after a disturbance
    but the amplitude of the oscillations will not change.

    So, a statically stable aircraft may be dynamically unstable.
    Dynamic instability may be prevented by an even distribution of weight inside the
    fuselage, avoiding too much weight concentration at the extremities or at the CG.
    Also, control surfaces’ max throws may affect the flight stability, since a too much
    control throw may cause instability, e.g. Pilot Induced Oscillations (PIO).

    Static stability is proportional to the stabiliser area and the tail moment.
    You get double static stability if you double the tail area or double the tail moment.
    Dynamic stability is also proportional to the stabiliser area but increases with the
    square of the tail moment, which means that you get four times the dynamic stability
    if you double the tail arm length.

    However, making the tail arm longer or encreasing the stabiliser area will move
    the mass of the aircraft towards the rear, which may also mean the need to make
    the nose longer in order to minimize the weight required to balance the aircraft…

    A totally stable aircraft will return, more or less immediately, to its trimmed state
    without pilot intervention.
    However, such an aircraft is rare and not much desirable. We usually want an
    aircraft just to be reasonably stable so it is easy to fly.
    If it is too stable, it tends to be sluggish in manoeuvring, exhibiting too slow
    response on the controls.

    Too much instability is also an undesirable characteristic, except where an
    extremely manoeuvrable aircraft is needed and the instability can be continually
    corrected by on-board ‘fly-by-wire’ computers rather than the pilot, such as a
    supersonic air superiority fighter.

    Lateral stability is achieved through dihedral, sweepback, keel effect and
    proper distribution of weight.
    The dihedral angle is the angle that each wing makes with the horizontal (see
    Wing Geometry).
    If a disturbance causes one wing to drop, the lower wing will receive more lift
    and the aircraft will roll back into the horizontal level.

    A sweptback wing is one in which the leading edge slopes backward.
    When a disturbance causes an aircraft with sweepback to slip or drop a wing,
    the low wing presents its leading edge at an angle more perpendicular to the
    relative airflow. As a result, the low wing acquires more lift and rises, restoring
    the aircraft to its original flight attitude.

    The keel effect occurs with high wing aircraft. These are laterally stable simply
    because the wings are attached in a high position on the fuselage, making the
    fuselage behave like a keel.
    When the aircraft is disturbed and one wing dips, the fuselage weight acts like
    a pendulum returning the aircraft to the horizontal level.

    The tail fin determines the directional stability.
    If a gust of wind strikes the aircraft from the right it will be in a slip and the fin
    will get an angle of attack causing the aircraft to yaw until the slip is eliminated.

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  • Longitudinal stability depends on the location of the centre of gravity, the
    stabiliser area and how far the stabiliser is placed from the main wing.
    Most aircraft would be completely unstable without the horizontal stabiliser.
    Non-symmetrical cambered airfoils have a higher lift coefficient, but they also
    have a negative pitching moment (Cm) tending to pitch nose-down, and thus
    being statically unstable, which requires the counter moment produced by the
    horizontal stabiliser to get adequate longitudinal stability.
    The stabiliser provides the same function in longitudinal stability as the fin does
    in directional stability.

    Symmetrical (zero camber) airfoils have normally a zero pitching moment,
    resulting in neutral stability, which means the aircraft goes wherever you point it.
    Reflexed airfoils (with trailing edge bent up) have a positive pitching moment
    making them naturally stable, they are often used with flying wings (without the
    horizontal stabiliser).

    It is of crucial importance that the aircraft’s Centre of Gravity (CG) is located
    at the right point, so that a stable and controllable flight can be achieved.
    In order to achieve a good longitudinal stability, the CG should be ahead of the
    Neutral Point (NP), which is the Aerodynamic Centre of the whole aircraft.
    NP is the position through which all the net lift increments act for a change in
    angle of attack.
    The major contributors are the main wing, stabiliser surfaces and fuselage.

    The bigger the stabiliser area in relationship to the wing area and the longer
    the tail moment arm relative to the wing chord, the farther aft the NP will be and
    the farther aft the CG may be, provided it’s kept ahead of the NP for stability.

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  • The angle of the fuselage to the direction of flight affects its drag, but has little
    effect on the pitch trim unless both the projected area of the fuselage and its
    angle to the direction of flight are quite large.
    A tail-heavy aircraft will be more unstable and susceptible to stall at low speed
    e. g. during the landing approach.
    A nose-heavy aircraft will be more difficult to takeoff from the ground and to
    gain altitude and will tend to drop its nose when the throttle is reduced. It also
    requires higher speed in order to land safely.

    The angle between the wing chord line and the stabiliser chord line is called
    the Longitudinal Dihedral (LD) or decalage.
    For a given centre of gravity, there is a LD angle that results in a certain
    trimmed flight speed and pitch attitude.
    If the LD angle is increased the plane will take on a more nose up pitch attitude,
    whereas with a decreased LD angle the plane will take on a more nose down
    pitch attitude.
    There is also the Angle of Incidence, which is the angle of a flying surface
    related to a common reference line drawn by the designer along the fuselage.
    The designer might want this reference line to be level when the plane is flying
    at level flight or when the fuselage is in it’s lowest drag position.
    The purpose of the reference line is to make it easier to set up the relationships
    among the thrust, the wing and the stabiliser incidence angles.
    Thus, the Longitudinal Dihedral and the Angle of Incidence are interdependent.

    Longitudinal stability is also improved if the stabiliser is situated so that it lies
    outside the influence of the main wing downwash.
    Stabilisers are therefore often staggered and mounted at a different height in
    order to improve their stabilising effectiveness.

    It has been found both experimentally and theoretically that, if the aerodynamic
    force is applied at a location 1/4 from the leading edge of a rectangular wing
    at subsonic speed, the magnitude of the aerodynamic moment remains nearly
    constant even when the angle of attack changes.
    This location is called the wing’s Aerodynamic Centre AC.
    (At supersonic speed, the aerodynamic centre is near 1/2 of the chord).

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  • In order to obtain a good Longitudinal Stability the Centre of Gravity CG
    should be close to the main wings’ Aerodynamic Centre AC.
    For wings with other than rectangular form (such as triangular, trapezoidal,
    compound, etc.) we have to find the Mean Aerodynamic Chord – MAC,
    which is the average for the whole wing.
    The MAC calculation requires rather complicated mathematics, so a simpler
    method called ‘Geometric Mean Chord’ GMC or ‘Standard Mean Chord’ SMC
    may be used as shown on the drawings below.
    MAC is only slightly bigger than GMC except for sharply tapered wings.
    Taper ratio = tip chord/root chord.

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  • To calculate MAC of a tapered wing, the following simplified equation
    may be used:
    MAC = root chord * 2/3 * ((1+T+T2)/(1+T))
    Where T is the wing’s taper ratio.
    The MAC distance from the center line may be calculated as follows:
    distance = half span * (1+2*T)/(3+3*T)

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  • For a delta wing the CG should be located 10% ahead of the geometrically
    calculated AC point as shown above.

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  • The MAC of an elliptical wing is 85% of the root chord and is located at 42.4% of
    the half wingspan from the root chord.
    Elliptical wing’s area = pi * wingspan * root chord/4
    The AC location for biplanes with positive stagger (top wing ahead of the bottom
    wing), is found according to the drawing below.

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  • For conventional designs (with main wing and horizontal stab) the CG location
    range is usually between 28% and 33% from the leading edge of the main
    wing’s MAC, which means between about 5% and 15% ahead of the aircraft’s
    Neutral Point NP.
    This is called the Static Margin, which is expressed as a percentage of MAC.
    When the static margin is zero (CG coincident with NP) the aircraft is considered
    “neutrally stable”.
    However, for conventional designs the static margin should be between 5% and
    15% of the MAC ahead of the NP.
    The CG location as described above is pretty close to the wing’s Aerodynamic
    Center AC because the lift due to the horizontal stab has only a slightly effect on
    the conventional R/C models.

    However, those figures may vary with other designs, as the NP location depends
    on the size of the main wing vs. the stab size and the distance between the main
    wing’s AC and the stab’s AC.
    The simplest way of locating the aircraft’s NP is by using the areas of the two
    horizontal lifting surfaces (main wing and stab) and locate the NP proportionately
    along the distance between the main wing’s AC point and the stab’s AC point.
    For example, the NP distance to the main wing’s AC point would be:
    D = L · (stab area) / (main wing area + stab area) as shown on the picture below:

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  • There are other factors, however, that make the simple formula above inaccurate.
    In case the two wings have different aspect ratios (different dCL/d-alpha) the NP
    will be closer to the one that has higher aspect ratio.
    Also, since the stab operates in disturbed air, the NP will be more forward than
    the simple formula predicts.
    The figure below shows a somewhat more complex formula to locate the NP but
    would give a more accurate result using the so called Tail Volume Ratio, Vbar.
    This formula gives the NP position as a percentage (%) of the wing’s MAC aft of
    the wing’s AC point.

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  • For those who are not so keen on formulas and calculations there is the
    Aircraft Center of Gravity Calculator, which automatically calculates the CG
    location as well as other usuful parameters based on the formula above.
    For Canards check the link below:
    Canard Center of Gravity Calculator

    For further equations on how to find the proper CG location with different wing
    shapes and design configurations including Canards, check here.

  • Stall and SpinOne of the first questions a pilot might ask, when converting to a new aircraft
    type, is “What’s the stall speed?”
    The reason for the enquiry is that usually, but not always, the approach speed
    chosen for landing is 1.3 times the stall speed.
    Stall is an undesirable phenomenon in which the aircraft wings produce an
    increased air resistance and decreased lift, which may cause an aircraft
    to crash.

    The stall occurs when the airflow separates from the upper wing surface.
    It happens when a plane is under too great an Angle of Attack (AoA).
    For light aircraft, without high-lift devices, the critical angle is usually around 16°.
    The picture below shows a stalled airfoil:

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  • Geometric Angle of Attack is the angle between the airfoil chord line and the
    direction of flight. The Angle of Attack is also known as Alpha.
    The angle of attack measured relative to zero coefficient of lift is called the
    Absolute Angle of Attack (Absolute AoA).
    There’s also the Pitch Angle, which is measured with respect to the horizon.
    For symmetric airfoils the Absolute AoA is equal to the Geometric AoA,
    whereas for asymmetric (cambered) airfoils these two angles are different, since
    these airfoils still produce lift at zero Geometric Angle of Attack as shown below.

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  • For airfoils of one family the symmetric airfoil stalls at a higher Geometric AoA
    compared with the cambered airfoil, however the cambered airfoil has higher
    lift coefficient and stalls at a higher Absolute AoA.
    As mentioned in the chapter Forces in Flight, the lift force is proportional to the
    density of the air r, the square of the airspeed V, the type of airfoil and to the
    wing’s area according to the formula:

    Lift force = 0.5 * r * V2 * wing’s lift coefficient * wing area

    Since lift coefficient is proportional to the angle of attack, the lower the airspeed
    the higher the angle of attack has to be in order to produce the same lift.

    Thus, stall may occur during take-off or landing, just when the airspeed is low:
    To keep altitude at low airspeed, the wing’s lift coefficient has to increase, and if
    a non-experienced pilot tries to lift the aircraft’s nose at a too low airspeed, it may
    exceed the critical angle of attack and stall occurs.
    If you’re flying near the stall speed and make a steep turn, the aircraft will stall.
    That’s because, if the aircraft stalls for instance at 20 knots in straight level flight,
    it will stall at 28.2 knots in a 60 degree banked turn.
    The rapid reduction in speed after passing the critical angle of attack means
    the wing is now unable to provide sufficient lift to totally balance weight and,
    in a normal stall, the aircraft starts to sink, but if one wing stalls before the
    other, that wing will drop, the plane falls out of the air. The ground waits below.

    Stalls may also occur at high airspeeds. If at max airspeed and full throttle the
    pilot suddenly applies excessive up elevator, the aircraft will rotate upwards,
    however, due to aircraft’s inertia, it may continue flying in the same direction
    but with the wings at an angle of attack that may exceed the stall angle.
    See an example here

    Stalling at high-speed gives a more dramatic effect than at low speed.
    This because the strong propeller wash causes one of the wings to stall first
    that combined with the high speed produces a snaproll followed by a spiral dive.
    This happens very fast causing the aircraft to dive at full throttle and unless
    there’s enough height for recovery, the crash will be inevitable.

    An aircraft with relatively low wing loading has a lower stall speed.
    (wing loading is the aircraft’s weight divided by the wing area)
    Since the airfoil also affects the stall speed and the max angle of attack, many
    aircraft are equipped with flaps (on the wing trailing edge), and some designs
    use slats (on the wing leading edge).
    Flaps increase the wing’s lift coefficient, but the simple ones may reduce the stall
    angle. Slats, on the other hand, increase the stall angle.

    Aircraft that are designed for Short Take-Off and Landing (STOL) use slots
    on the wing’s leading edge together with flaps on the trailing edge, which gives
    high lift coefficient and remarkable slow flying capabilities by allowing greater
    angle of attack without stalling.

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  •  Cruise                     Climb
    

    The leading edge slots may prevent the stall up to approximately 30 deg. angle
    of attack by picking up a lot of air from below, accelerating the air in the funnel
    shaped slot (venturi effect) and forcing the air around the leading edge onto the
    upper wing surface.

    The disadvantage of the slots and flaps is that they produce higher drag.
    Since the high lift coefficient is only needed when flying slowly (take-off, initial
    climb, final approach and landing) some designs use retractable devices,
    which closes at higher speeds to reduce drag.

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  • Such devices are seldom used in model aircraft (especially the smaller ones),
    mainly due to its complexity and also the increasing of wing loading, which
    may counter-act the increased lift obtained.
    The wing’s aspect ratio (AR) also affects the overall lif coefficient of the wing.
    For a given Re, the wing with higher AR (with long wingspan and small chord)
    reaches higher lift coefficient, but stalls at a lower angle of attack than the wing
    with low AR as shown below:

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  • However, for a given wing area, increasing the aspect ratio may result in a too
    small wing chord with a too low Re number, which may significantly reduce the lift
    coefficient. This is likely to occur with small indoor planes.
    Another method to improve an aircraft’s stall characteristics is by using wing
    washout, which refers to wings designed so that the outboard sections
    have a lower angle of attack than the inboard sections in all flight conditions.

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  • The outboard sections (toward the wing tips) will reach the stalling angle
    after the inboard sections, thus allowing effective aileron control as the stall
    progresses. This is usually achieved by building a twist into the wing structure
    or by using a different airfoil in the outboard section.
    A similar effect is achieved by the use of flaps.
    The aileron drag is a further factor that may cause an aircraft to stall.
    When the pilot applies aileron to roll upright during low speed, the downward
    movement of the aileron on the lower wing might take an angle on that part of
    the wing past the critical stall angle. Thus that section of wing, rather than
    increasing lift and making the wing rise, will stall, lose lift and the aircraft
    instead of straightening up, will roll into a steeper bank and descend quickly.

    Also the wing with the down aileron often produces a larger drag, which may
    create a yaw motion in the opposite direction of the roll.
    This yaw motion partially counteracts the desired roll motion and is called
    the adverse yaw.

    Following configurations are often used to reduce aileron drag:
    – Differential ailerons where the down-going aileron moves through a smaller
    angle than the up-going.
    – Frise ailerons, where the leading edge of the up-going aileron protrudes
    below the wing’s under surface, increasing the drag on the down-going wing.
    – And the wing washout.

    Stall due to aileron drag is more likely to occur with flat bottom wings.
    Since differential ailerons will have the opposite effect when flying inverted,
    some aircraft with symmetrical airfoils designed for aerobatics don’t use
    this system.
    The picture below illustrates an example of a Frise aileron combined with
    differential up/down movement.

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  • Another factor that affects the aircraft’s stall characteristics is the location of
    its centre of gravity CG.
    A tail-heavy aircraft is likely to be more unstable and susceptible to stall at low
    speed, e. g. during the landing approach.
    Downwind stall:
    For instance, a powered plane flying north with airspeed of 30 knots against a
    30 knots headwind has zero ground speed.
    If you turn 90 deg. left (west), the plane’s airspeed still is 30 knots but is now
    drifting 30 knots to the south resulting in 42 knots ground speed to the southwest.
    If the plane keeps turning south, the drift due to the wind is still 30 knots but now
    the ground speed becomes 30+30 = 60 knots, while the airspeed still is 30 knots.

    The pilot on the ground will see the ground speed but not the airspeed, and since
    the plane seems to move much faster flying downwind, the pilot may instinctively
    slow down the plane below the stall speed.
    This results in a pilot-induced stall due to the optical illusion of the plane’s higher
    ground speed when flying downwind.

    Recovering from a stall:

    In order to recover from a stall, the pilot has to reduce the angle of attack
    back to a low value. Despite the aircraft is already falling toward the ground,
    the pilot has to push the stick forward to get the nose even further down.
    This reduces the angle of attack and the drag, which increases the speed.

    After the aircraft gained speed and the airflow incidence on the wing becomes
    favourable, the pilot may pull back on his stick to increase the angle of attack
    again (within allowable range) restoring the lift.
    Since recovering from a stall involves some loss of height, the stall is most
    dangerous at low altitudes.

    Engine power can help reduce the loss of height, by increasing the velocity
    more quickly and also by helping to reattach the flow over the wing.
    How difficult it is to recover from a stall depends on the plane. Some full-size
    aircraft that are difficult to recover have stick shakers: the shaking stick alerts
    the pilot that a stall is imminent.

    Spin

    A worse version of a stall is called spin, in which the plane spirals down.
    A stall can develop into a spin through the exertion of a sidewise moment.
    Depending on the plane, (and where its CG is located) it may be more difficult
    or impossible to recover from a spin.
    Recovery requires good efficiency from the tail surfaces of the plane; typically
    recovery involves the use of the rudder to stop the spinning motion, in addition
    to the elevator to break the stall. However the wings might block the airflow to
    the tail.
    If the centre of gravity of the plane is too far back, it tends to make recovery
    much more difficult.

    Another circumstance that may cause loss of control is when a hinged control
    surface starts to flutter.
    Such flutter is harmless if it just vibrates slightly at certain airspeed (possibly
    giving a kind of buzzing sound), but ceases as soon as the airspeed drops.
    In some cases however, the flutter increases rapidly so that the model is no
    longer controllable.
    The pilot may not be aware of the cause and suspect radio interference instead.
    To reduce the flutter, the control linkages should not be loosely fitted and the
    push rods should be stiff.
    Long unbraced push rods can create flutter as vibration whips them around.
    In some difficult cases the control surface has to be balanced, so that its centre
    of mass (gravity) is ahead of the hinge line. It should be located at about 60-65%
    of the length of the control surface from its inner end:

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