Kris...
30cc
You need to put up with a whole lot of ugly before the goodness starts happening.....
THE KEYS TO 3D
- The lower (lighter) the wing loading the better: lower stall speeds and better knife edge capability. The ability to fly away from a botched maneuver is important.
- The higher the power to weight ratio the better: blast out of trouble or jump out of a hover.
- The more the control surfaces move the better: faster maneuvering.
- The larger the control surfaces the better: more control of the air.
- The more powerful the servos the better: to prevent flutter.
- Digital servos: precise motion throughout the range and tighter centers.
- The faster the servos the better: faster corrections.
- The larger the fuselage side area the better: better yaw control.
- The larger the size the plane the better: less sensitive.
- A computer radio: mix out quirks, switch rates easily using one condition switch.
- The correct amount of right thrust: the plane must go up straight in a hover.
- Lots of money: buy the best, stretch the envelope, have a backup.
- Nerves of steel: the lower the better.
- Bulletproof airframe: don't have a mechanical failure, especially servo linkages.
- Bulletproof engine/motor : hovering on the deck has an unhappy ending if the engine/motor quits.
- Rearward CG: flies inverted virtually hands off for better manoeuvrability.
- Extensive preflight: you can't afford a mechanical failure in the air which should have been caught on the ground.
A 3D Pilot Will:
Fly with awesome precision.
Fly a straight and level line, even in high wind.
Always fly parallel to the runway. Don't drift and don't purposely fly skewed to the runway.
Either fly straight out or straight in or circle out or in.
Always be flying maneuvers, never just flying around aimlessly.
Be acutely aware of the wind direction and speed to compensate with rudder and throttle.
Have a plan on what to fly before taking off.
Always be a better pilot after each flight by paying attention to details and learning something each flight.
Fly maneuvers gracefully and at constant speed with the same quality both upwind and downwind.
Fly all maneuvers under control at all times. While some maneuvers may scare the casual observer, other pilot's familiar with your flying will be amused.
Practice a lot.
Roll and snap to the left as well and as often as to the right.
Present manoeuvres properly by centering loops, rolls, Cuban 8's.
Go home with plane intact.
How about a lesson in 3D ?
Just to get started. It seems that everyone that is on the fence about getting started in this flying style usually wonders about the basic hover, by this I mean to hover an airplane on a vertical axis in a still position (hanging on the prop). In this maneuver I consider to be the basic of basics (although some would disagree and say the basic of the basics is the harrier, but everyone has an opinion and they are entitled to that as a human). Now the assuming that the setup on the airplane is aerodynamically neutral (upright and inverted flight flys the same, basically but I will go over that in another post because that is a long discussion) and you have at least a 1 to 1 weight to power ratio (preferably a 2 to 1 ratio because this will save the beginner alot of headache and make this maneuver much more forgiving).
Start out into what is called a wall. This is too easy, it is just a maneuver to get the aicraft into a vertical position. At strait and level flight, at a medium speed (like a landing speed but hot) making sure that your wings are upright and absolutely level pull full up elevator as you reduce throttle to about a quarter of your engine power (I said power not stick position) this will take some getting used to but learn to use that left stick and manage power. When the aircraft gets to that verticle position release the elevator to neutral and begin to increase the power just enough to keep it from falling and not too much to keep it from rising.
Now we are in a hover so heres where it gets a little tricky and is where most hit there mental wall here (so 99% of folks listen up, the other 1% are probally laughing at me right now for talking too much about the wall). All we need to understand are the forces acting on the aircraft and what we have to work with to control these forces.
First of all we need to manage the power. Once we have the correct power level to hover all we need is a click or two on the throttle stick to make corrections. That being said the more throttle we have the more control athourity we have on our control surfaces due to the amount of air moving over the surfaces. As we increase power we have just induced torque in the airfraime causing the plane to roll to the left which brings us to the next step.
Right aileron - We will counteract this left torque by applying right aileron (too easy) but remember what I said about increasing power, if you increase power without applying a little more right aileron you will start to roll left, decreasing throttle without reducing the amount of right aileron you will start to roll right (clear as mud?). When starting out lets keep the aircraft with the top towards us for orientation purposes.
Rudder - this is now our vertical axis right and left control(assuming that the canopy is facing us). You will find that if the engine thrust line is basically correct you will still need a little right rudder, again to counteract engine torque. Be careful not to let the aircraft get too out of wack on the yaw or you will be traveling all over the place trying to "catch up with it" (we all do it starting out so dont get discouraged).
Elevator control - This usually stays pretty effective in a hover, so all we are doing here is keeping the towards and away axis in check (again assuming that the canopy is towards us). It is very important to keep this axis in a vertical position throughout this maneuver because if we dont we will induce what is called wing rock (another discussion) simply said the wings will rock side to side and you will be fighting your rudder the whole time.
Now we are not only in a hover, but we are controlling it for more than a half a second that most folks do. I will say this, If you are trying this far away "dot range" you will not see the minor corrections needed to keep it controlled. Also if you are too high this has the same effect. Im not saying you should start out head high or lower (although it does save damages to a minimum on a lighter airplane in case of an unfortunate "dumb thumb") but at least so you can see the aircraft good enough so you can see the control surfaces move.
You've seen this “new” 3D flying, maybe even tried some but if you're like most flyers you really don't know exactly how to do it. In this article I’ll let you in on my tips, tricks and secrets that I’ve taught myself over the past few years of flying 3D. 3D is most often defined as ‘purposely flying an airplane in a fully stalled, yet controlled condition where-in the propeller thrust alone is generating the balance of lift keeping the airplane aloft.’ 3D is at the top of the Extended Flight Envelope surpassed only by 4D in which airplanes are out-fitted with a reversing-pitch prop allowing it to fly backwards and even hover nose-down for a short time!
So you have a plane that’s over powered and your brave enough to pull it vertically and hang it on the prop for a few seconds before it falls of to the side and plunges earthward and you think that’s something! Well that it how 3D most-likely started, but just because your airplane can prop-hang doesn’t mean it is a “3D plane”. Any aircraft with enough power can prop-hang but prop-hanging isn’t hovering nor is it “3D”. Flying 3D takes more than a 1:1 thrust to weight ratio. It also requires huge control surfaces and throws from those surfaces, the correct wing platform, Center of Gravity and an ability to carry some inertia. Without these an airplane cannot perform 3D maneuvers, at least not well. The wing and horizontal stabilizer need to be very close to in-line with the thrust line. The CG has to be quite aft and very centered laterally as well as vertically on the aircraft to fly 3D well so that the pilot doesn’t have to fight the airplane into and out-of maneuvers or transitions. Setup and balance is the second most important thing for 3D next to a lot of power.
The proper setup can make or literally break a 3D airframe. The difference in performance between a properly setup plane and a poorly setup plane is night and day! We’ll start with the nose and work back. The motor, which you need a lot of, enough to have at least a 2:1 thrust over weight power ratio, needs to have proper down and right thrust. 2* down and 3* right is a good starting point because unlike a regular sport aerobatic you are swinging a much larger prop, there for there is more torque and its compounded that much more do you the RPMs the engine can swing the prop, the high Angles Of Attach you’ll put the airplane through and the fact that the airplane is usually flying only on the propeller so the torque effects and P-factor are much more prevalent and apparent. There is no way to eliminate the prop effects, but you can bring them to a minimum with the correct down and right thrust. The prop is another huge performance item. You need a very large and low pitch prop. This will create more thrust over a smaller and higher pitch “bench” prop. If you have too much pitch your prop will “cavitate” while in low-airspeed high throttle flight making you loose lots of thrust and prop wash. As we move back, we come to the wing, which as I said should be in-line with the thrust line (which is also the middle of the prop and drive shaft). If the wing is too high or too low it will not do a lot of maneuvers well, nor will the ailerons receive good, smooth airflow from the prop wash. With the wing too high or low the knife edge coupling will also be very bad, so much so that the pilot would have to concentrate more of flying the KE, rather than doing the maneuver. And not to be forgotten, the airfoil HAS to be symmetrical to fly 3D maneuvers well. Next in line would be the CG. This is more critical than anything else for good 3D abilities next to having enough power to do them. The 3D CG is usually 30-40 percent of the wing chord as measured back from the wings leading edge at the root. The components of the airframe also need to be situated so that the CG is not only balancing the airplane fore/aft, but in the lateral (side to side) and vertical (top to bottom) plains as well. Centered as close to the middle and at the thrust line as possible. It likely cannot be perfect, but it can get very close. Your plane needs to be balanced so that it will fly hands off at half throttle (50% power) upright or inverted (upside down) without the need for elevator trim. It should feel very neutral and somewhat buoyant if the CG is correct. When properly balanced your plane should fly with only VERY minimal, in any trim inputs, strait and level, RSU or inverted at half throttle. Next come the ailerons. They need to be very wide and extend from the root to the tip, if not you will not get good prop wash over them and they will be stalled along with the wing in high alpha attitudes. They need at the very least 45*of throw, but about 60* is the norm for a good 3D plane. The tail moment (length of the tail fro the wing’s trailing edge to the horizontal stabilizer’s leading edge) is next. 3D planes are usually short coupled, meaning the tail moment is short. If the moment is too long it will not flip and pitch fast enough, or at all which will make most all 3D tricks UN-doable. But if the moment is too short it will be so sensitive to pitch changes that it will be too hard to manage in most maneuvers even for a competent 3D pilot. A good “rule of thumb” for the shortest tail moment would be about the length from the prop to the CG, any shorter and it may be too short. Next is the fuselage inside the tail moment, which isn’t a big deal, but having a tall back, like a turtle deck, gives the plane more fuselage area to “fly” on during knife edge (KE). Last but not least would be the tail feathers. The stabilizers should be attached very well but not be too large as compared to the size of the control surfaces. If they have too long of a chord they will do more to slow the rotation of the plane rather than aid it. Some 3D airplanes don’t even have any horizontal or vertical stabilizers. The elevator and rudder are “flying” in that they are hinged on a pivot on the fuselage. The whole horizontal or vertical stabilizer will move! This is something really cool, but not required at all. The control surfaces, both rudder and elevator, have to be quite large with at least 45-60 degrees of throw. Anything less and it will be very hard to do most 3D maneuvers. For good KE the horizontal stab must be very close to in-line with the wing or just below it for low-coupling. The rudder does need to be large, but not too tall. If the rudder is too tall or has too much counterbalance the rudder could roll the airplane as much as make it yaw, which would make KE and lots of rolling maneuvers very hard to do because it would tend to over roll the airplane, but not roll it enough so that the ailerons wouldn’t be needed. You’d be fighting with the ailerons to counter the rudder’s roll effect rather than make the airplane roll axially. Keep all these in mind when searching for your 3D airplane.
As a competent pilot you have to be able to control your aircraft at all speeds and attitudes with all four controls, The aileron, elevator, rudder and throttle. Without than ability, learning 3D will never happen for you. You have to be a “two stick” pilot in that you HAVE to know how to fly an airplane with all four controls, where as most sport/Sunday fliers rarely use the rudder or manage the throttle. They just nail the throttle on takeoff, hoping it the takeoff is quick so it doesn’t get “squirrelly” then they bank and yank until they are out of fuel or get board, then chop the throttle and head for what they hope is the middle of the runway and fly the airplane to the ground, hopefully onto its wheels during all three or four bounces/skips before it rolls to a stop either at the end of the runway or off the side. Sound like you? Well, try flying around using your left thumb before you try some 3D. Even the most basic 3D maneuvers and tricks take good rudder coordination. To gain a quick sense of using the rudder, fly your trainer or most basic sport model making good use taxing the model, making long takeoff roll outs before lift off keeping the model down the center of the runway using your rudder. Make coordinated turns and circles. Try some flat turns, where-in you fly in a circle while keeping the wings level the whole time with your ailerons but using your rudder to make the turn. Try some forward slips and maybe some knife edge. After you’ve got confidence in flying those maneuvers concentrate of cross-wind landings, forward slips to landing, and then graduate yourself to rolling circles. Practicing rolling circles will really aid you in learning to coordinate all three controls and will progress you easily into rolling harriers and rolling loops!
After getting friendly with your left stick and rudder anyone can now teach themselves to fly 3D! But first you need a good model. Not just a good 3D capable plane, but one that is cheap and durable. The best way to go is either with a FFF or EPP foam airframe, like Twisted Hobbys Crack Yak or Crack Pitts , All are very good 3D trainers and super cheap and can be flown with very in-expensive gear. Just like learning to fly, you WILL crash! Just stay at a comfortable altitude and done be afraid to bail out of a maneuver early or just “pan-cake” on the ground. Keep some hot glue or CA around! ; )
Most 3D maneuvers are not specifically derived from standard aerobatic/IMAC maneuvers. They are a breed of their own but a good knowledge and ability to execute standard maneuvers will help to say the least. I’ll list the known 3D/Freestyle maneuvers starting with the easiest to the hardest to perform.
Harrier - A very slow forward flight motion with a high Angle Of Attack. One can fly strait or circle using the rudder to turn the desired direction and opposite aileron to rudder to keep the wings level, using throttle to maintain the desired altitude. Find the AOA your plane likes best, which is where you still have aileron control without the wings rocking back and forth.
Inverted Harrier - The same as the above, just inverted. Most capable pilots find this easier than a standard harrier due to the wing being above the CG. It tends to have less wing rock, but your rudder and aileron inputs are reversed, and there is a fair amount of “pucker factor” seeing your plane’s tail so close to the ground and the landing gear above it.
Elevator - This is just a descending harrier. You can make it as steep or gradual as you are comfortable with by using your throttle, again find a good AOA where the wing doesn’t rock. This can also be done in Knife Edge or as a rolling harrier!
Flat Spin - A spin induced with full elevator, full rudder, and aileron. Once the spin is initiated you will level the wings with the ailerons and increase engine speed a bit to pull the aircraft around. This will in turn flatten the spin. The wings HAVE to be FULLY stalled to get a good and level axial rotation. Not necessarily a 3D maneuver by most 3D pilot‘s definitions, but you have to know how to do one properly to do some 3D maneuvers.
Knife Edge Spin - Its easiest entered from a vertical climb. Add full LEFT rudder at the top just before the stall and let the plane rotate 270* then apply throttle and full down elevator, your plane might require aileron input as well to keep the wings perpendicular to the ground. This will throw you into a type of falling lomcevoc where in your plane is tumbling over its pitch axes. Its just a flat spin turned on its side. Manage your power to make the spin as slow or as fast and violent as you want.
Hover/Torque Roll - A hover is a controlled prop-hang in that you are holding your airplane vertically without any apparent movement or motion, forward, backward, sideways or up/down. You pull the aircraft into a completely vertical attitude and allow the propeller to hold the airplane in the air like a helicopter. One can keeping the wings from spinning by adding right aileron or just let the plane spin on its own because of the torque from the prop, which is a torque roll. When first learning most pilots find it easier to induce a slightly faster spin/roll. This will minimize the time the belly is towards you, which is that hardest part of hovering/torque rolling.
Wall and Alien Wall - The Wall maneuver is where your plane starts from a horizontal flight path and immediately transitions 90* into a vertical climb, as if it were rolling along the ground and hit a wall and started to climb the wall. An Alien Wall is the same only much more violent (like a “UFO” sometimes seems to do) in that it is entered with much more airspeed and G. This maneuver is usually immediately ended in a hover or a waterfall.
Pin Wheel - This is a simple maneuver but it requires a lot of power and very rearward CG and a ton of rudder to complete properly. Start from a hover, yaw to the right a few degrees then simultaneously add full right rudder and full power to complete at least one full axial rotation around its CG as if the plane were stuck onto a pinwheel and spun. Some aileron input might be needed to keep the plane from falling out into a flat spin and a touch of down elevator can make it rotate a little faster.
Snap/Pop up ! - The Snap-Up is when the airplane comes to a hover from a horizontal flight path with a snap-roll in the middle. Basically a wall with a snap in the transition and ending immediately in a hover. Try not to over rotate the snap roll, just initiate the snap with the usual full elevator, rudder and aileron but half way thru the snap neutralize the elevator then stop the rotation by neutralizing aileron and rudder, then pull full up with a burst of power to finish the vertical transition. It reads harder than it actually is. A Pop-Up is the same maneuver only without the snap.
Waterfall - The waterfall is a maneuver where the plane pivots 360 degrees over it’s pitch axes with very little forward motion and altitude change. This maneuver takes either a lot of power or inertia to complete. It can be finished with just one flip/rotation or multiple rotations. It is usually done “on the outside” with down elevator which is easier because its not fighting prop torque.
Yo-Yo - Entered from a hover or wall, power out vertically to gain some altitude (not too much) then enter a ½ waterfall. The plane will flip around into an inverted elevator, let the plane fall back to the ground and power up and do it again. This maneuver looks best doing it two to three times making the loop smaller and lower each time, ahh…like a Yo-yo!
Falling Leaf/Tic-Toc - From altitude enter this maneuver from a roller coaster, harrier, hover, or just slow the plane to a forward and level stall. Push the plane over onto its back with a burst of power, then immediately onto its belly with another quick and hard burst of power. Do this several times in a row, like a leaf flopping slowly to earth from a tall branch. Try to keep the plane parallel to the ground so you don’t over rotate into a waterfall. You may need to use right rudder with the throttle bursts to keep the plane strait.
Pogo - This is another hovering maneuver. Rapidly climb and then descend (tail slide) in a hover as if the plane were riding a pogo stick! Its most often done in a hover, but some better than I can do a torque rolling pogo too!
Snap Rolls -The snap roll is commonly used when flying 3D so I will add it to the list. The Snap Roll by AMA aerobatics code definition is "a simultaneous, rapid auto-rotation in the pitch, yaw and roll axes in a stalled wing attitude." Now, to do a snap roll there are some things the plane must do.
1. You first need to sharply increase the angle of attack to put the plane into a position where it will stall without changing the track (much) This is easier said than done but a little nose break is really necessary to get a good snap and hold your line. This is done with a quick pulse of up elevator to "break" the nose and put the wing in a position to stall.
2. Within a split second of that pulse of elevator input you push the rudder full over (to start learning to snap) and at the same time input full aileron deflection in the same direction as the rudder.
**What you should see then is called "rapid auto-rotation". When you input the rudder you get "YAW" which means one wing speeds up, and the other slow rapidly and stalls. This initiates a sharp roll in the direction of the rudder input because one wing stops flying. Technically you should not "Need" to use ailerons, but with RC models the ailerons help to get the process started. You should not be depending on the ailerons for the rotation, if you are its not snapping they are just there to clean it up a little.
3. To keep the plane on heading as stated about you neutralize the elevator 1st and then the ailerons and rudder. All of this happens in less than 1 second.
Again,
Initiate stall in the wing by sharply pitching.
Stall the wing by inputting the rudder
Ailerons to clean up the rotation.
Neutralize at just the right moment to stop roll.
It is sort of a J pattern laid on its side.
Tail Slide - Bring the plane into a vertical climb/hover then reduce the throttle to below that at which the plane hovers and by controlling the slide backwards strait down with backward control inputs bring it back down to its starting altitude or below that even. It is very hard to do and nearly impossible to complete if you chop the throttle completely because there will be no prop wash over the surfaces to keep the plane from toppling over nose first.
Harrier Roll - Like the Harrier maneuver only roll combined and performed simultaneously in flight. Its not so hard, it just takes a little practice to get the pattern down. If rolling to the left use LEFT aileron and begin the pattern of RIGHT rudder, DOWN elevator, LEFT rudder, UP elevator and repeat. After you get the pattern down you can “come in” a little early on the pattern to get the plane to harrier roll in a right hand circle or one can come in late to make a left-hand circle. Most pilots find it easiest to continuously bump the throttle during the maneuver to keep the roll rate and altitude under control.
Rolling Loop - Using the same technique as the rolling harrier add full power to make your up-line and pull the power back as needed to make the top of the loop round, on the down side you’ll have to get over the pucker factor and really work your thumbs because you’ll have to apply near full power again on the last quarter of the loop to get it to come out and not smash into the ground, but too much and it will come out of the loop too quickly and the loop will not be round.
Parachute - This maneuver is a vertical diving roll that virtually stops its descent as it instantaneously enters into flat upright position. The transition has to be very quick so that the inertia continues to push the plane strait down (as if it deployed a parachute and it floating down) instead of flying out of the maneuver in an elevator.
Panic - The Panic is simply the parachute maneuver only ending with the plane inverted and much closer to the ground.
Blender - This maneuver is like the previous only ending in a flat spin. I’ve also seen it done ending in a KE spin instead of a flat spin.
Blaino Draino - Start from straight and level, pull vertical to a fair altitude and chop throttle, pull full elevator to flip back over for a vertical plunge. Roll the plane until your close to the ground then quickly stop the roll about 1 mistake high and pull full up elevator with full power all at the same time making the plane instantly transition into a harrier with rudder getting very close to the ground. It can be exited immediately into a hover or waterfall, or any maneuvers that start with a nose-high attitude.
Roller Coaster - This is basically a horizontal falling leaf, starting from slow level flight pitching the airplane strait down then strait back up then strait back down again. If you enter it with too much forward speed you will over rotate and into a waterfall, not enough speed and you’ll not have enough forward inertia to make at least one down, one up and one down pitching sequence before your plane is no linger moving forward.
Terminator - Its when the plane is flying straight and level and then makes a sudden 90* dive straight down. When the plane gets close to the ground pull out suddenly and fly out of it with full power, think of the exit as a wall on its side, the ground being parallel and only a couple feet below the imaginary wall your driving you plane on.
This is just a selection of 3D manoeuvres there are many more out there that are signature moves of professional RC pilots or combinations of these. Like everything in life and especially in this hobby it all just takes practice. Set a goal for each ~10 minute flight to learn ONE maneuver and become confidant with it before moving onto another. Once you feel comfortable flying all these moves try stringing a few together in one short sequence of 3 or 4 tricks. After you can do all 3 or 4 in a row consistently try adding a couple more at a time until you have a 4 or 5 minute routine put together! This is very fun and as challenging to do as it is to learn the moves themselves. Note that no plane can just jump from any one move to another! A 3D pilot has to manage his airspeed and airspace so that too many G’s aren’t pulled or so you don’t drive right into the dirt! For example you can’t go from a panic strait into a falling leaf or you’ll fly right into our archenemies, the earth! Try doing a rolling loop into a wall, then into a tail slide. Or try a wall into a waterfall, then into an inverted harrier. Do not enter a violent maneuver with too much forward speed, for example a panic with too much throttle on the down-line. When the plane reaches the point of the transition it will either over rotate or you could just blow the wings right off. One can’t enter a quick maneuver without enough speed/inertia, which will likely only have the consequence of not being able to complete the maneuver and making you look bad. Unless you are too close to the ground, for example; you do not have enough airspeed to finish the bottom of a rolling loop, try splicing maneuvers together as well, sometimes called 3F, or Flip Flop Flying. Cut maneuvers short or in half and immediately transition into another, for example: A half rolling loop into a Terminator at the top, then throw in a falling leaf or harrier roll at the bottom of the Terminator. Keep the “down time” or “setup time” between maneuvers minimal. This will keep your adrenaline, heart and your thumbs pumping and the peanut gallery on their toes!
THE KEYS TO 3D
- The lower (lighter) the wing loading the better: lower stall speeds and better knife edge capability. The ability to fly away from a botched maneuver is important.
- The higher the power to weight ratio the better: blast out of trouble or jump out of a hover.
- The more the control surfaces move the better: faster maneuvering.
- The larger the control surfaces the better: more control of the air.
- The more powerful the servos the better: to prevent flutter.
- Digital servos: precise motion throughout the range and tighter centers.
- The faster the servos the better: faster corrections.
- The larger the fuselage side area the better: better yaw control.
- The larger the size the plane the better: less sensitive.
- A computer radio: mix out quirks, switch rates easily using one condition switch.
- The correct amount of right thrust: the plane must go up straight in a hover.
- Lots of money: buy the best, stretch the envelope, have a backup.
- Nerves of steel: the lower the better.
- Bulletproof airframe: don't have a mechanical failure, especially servo linkages.
- Bulletproof engine/motor : hovering on the deck has an unhappy ending if the engine/motor quits.
- Rearward CG: flies inverted virtually hands off for better manoeuvrability.
- Extensive preflight: you can't afford a mechanical failure in the air which should have been caught on the ground.
A 3D Pilot Will:
Fly with awesome precision.
Fly a straight and level line, even in high wind.
Always fly parallel to the runway. Don't drift and don't purposely fly skewed to the runway.
Either fly straight out or straight in or circle out or in.
Always be flying maneuvers, never just flying around aimlessly.
Be acutely aware of the wind direction and speed to compensate with rudder and throttle.
Have a plan on what to fly before taking off.
Always be a better pilot after each flight by paying attention to details and learning something each flight.
Fly maneuvers gracefully and at constant speed with the same quality both upwind and downwind.
Fly all maneuvers under control at all times. While some maneuvers may scare the casual observer, other pilot's familiar with your flying will be amused.
Practice a lot.
Roll and snap to the left as well and as often as to the right.
Present manoeuvres properly by centering loops, rolls, Cuban 8's.
Go home with plane intact.
How about a lesson in 3D ?
Just to get started. It seems that everyone that is on the fence about getting started in this flying style usually wonders about the basic hover, by this I mean to hover an airplane on a vertical axis in a still position (hanging on the prop). In this maneuver I consider to be the basic of basics (although some would disagree and say the basic of the basics is the harrier, but everyone has an opinion and they are entitled to that as a human). Now the assuming that the setup on the airplane is aerodynamically neutral (upright and inverted flight flys the same, basically but I will go over that in another post because that is a long discussion) and you have at least a 1 to 1 weight to power ratio (preferably a 2 to 1 ratio because this will save the beginner alot of headache and make this maneuver much more forgiving).
Start out into what is called a wall. This is too easy, it is just a maneuver to get the aicraft into a vertical position. At strait and level flight, at a medium speed (like a landing speed but hot) making sure that your wings are upright and absolutely level pull full up elevator as you reduce throttle to about a quarter of your engine power (I said power not stick position) this will take some getting used to but learn to use that left stick and manage power. When the aircraft gets to that verticle position release the elevator to neutral and begin to increase the power just enough to keep it from falling and not too much to keep it from rising.
Now we are in a hover so heres where it gets a little tricky and is where most hit there mental wall here (so 99% of folks listen up, the other 1% are probally laughing at me right now for talking too much about the wall). All we need to understand are the forces acting on the aircraft and what we have to work with to control these forces.
First of all we need to manage the power. Once we have the correct power level to hover all we need is a click or two on the throttle stick to make corrections. That being said the more throttle we have the more control athourity we have on our control surfaces due to the amount of air moving over the surfaces. As we increase power we have just induced torque in the airfraime causing the plane to roll to the left which brings us to the next step.
Right aileron - We will counteract this left torque by applying right aileron (too easy) but remember what I said about increasing power, if you increase power without applying a little more right aileron you will start to roll left, decreasing throttle without reducing the amount of right aileron you will start to roll right (clear as mud?). When starting out lets keep the aircraft with the top towards us for orientation purposes.
Rudder - this is now our vertical axis right and left control(assuming that the canopy is facing us). You will find that if the engine thrust line is basically correct you will still need a little right rudder, again to counteract engine torque. Be careful not to let the aircraft get too out of wack on the yaw or you will be traveling all over the place trying to "catch up with it" (we all do it starting out so dont get discouraged).
Elevator control - This usually stays pretty effective in a hover, so all we are doing here is keeping the towards and away axis in check (again assuming that the canopy is towards us). It is very important to keep this axis in a vertical position throughout this maneuver because if we dont we will induce what is called wing rock (another discussion) simply said the wings will rock side to side and you will be fighting your rudder the whole time.
Now we are not only in a hover, but we are controlling it for more than a half a second that most folks do. I will say this, If you are trying this far away "dot range" you will not see the minor corrections needed to keep it controlled. Also if you are too high this has the same effect. Im not saying you should start out head high or lower (although it does save damages to a minimum on a lighter airplane in case of an unfortunate "dumb thumb") but at least so you can see the aircraft good enough so you can see the control surfaces move.
You've seen this “new” 3D flying, maybe even tried some but if you're like most flyers you really don't know exactly how to do it. In this article I’ll let you in on my tips, tricks and secrets that I’ve taught myself over the past few years of flying 3D. 3D is most often defined as ‘purposely flying an airplane in a fully stalled, yet controlled condition where-in the propeller thrust alone is generating the balance of lift keeping the airplane aloft.’ 3D is at the top of the Extended Flight Envelope surpassed only by 4D in which airplanes are out-fitted with a reversing-pitch prop allowing it to fly backwards and even hover nose-down for a short time!
So you have a plane that’s over powered and your brave enough to pull it vertically and hang it on the prop for a few seconds before it falls of to the side and plunges earthward and you think that’s something! Well that it how 3D most-likely started, but just because your airplane can prop-hang doesn’t mean it is a “3D plane”. Any aircraft with enough power can prop-hang but prop-hanging isn’t hovering nor is it “3D”. Flying 3D takes more than a 1:1 thrust to weight ratio. It also requires huge control surfaces and throws from those surfaces, the correct wing platform, Center of Gravity and an ability to carry some inertia. Without these an airplane cannot perform 3D maneuvers, at least not well. The wing and horizontal stabilizer need to be very close to in-line with the thrust line. The CG has to be quite aft and very centered laterally as well as vertically on the aircraft to fly 3D well so that the pilot doesn’t have to fight the airplane into and out-of maneuvers or transitions. Setup and balance is the second most important thing for 3D next to a lot of power.
The proper setup can make or literally break a 3D airframe. The difference in performance between a properly setup plane and a poorly setup plane is night and day! We’ll start with the nose and work back. The motor, which you need a lot of, enough to have at least a 2:1 thrust over weight power ratio, needs to have proper down and right thrust. 2* down and 3* right is a good starting point because unlike a regular sport aerobatic you are swinging a much larger prop, there for there is more torque and its compounded that much more do you the RPMs the engine can swing the prop, the high Angles Of Attach you’ll put the airplane through and the fact that the airplane is usually flying only on the propeller so the torque effects and P-factor are much more prevalent and apparent. There is no way to eliminate the prop effects, but you can bring them to a minimum with the correct down and right thrust. The prop is another huge performance item. You need a very large and low pitch prop. This will create more thrust over a smaller and higher pitch “bench” prop. If you have too much pitch your prop will “cavitate” while in low-airspeed high throttle flight making you loose lots of thrust and prop wash. As we move back, we come to the wing, which as I said should be in-line with the thrust line (which is also the middle of the prop and drive shaft). If the wing is too high or too low it will not do a lot of maneuvers well, nor will the ailerons receive good, smooth airflow from the prop wash. With the wing too high or low the knife edge coupling will also be very bad, so much so that the pilot would have to concentrate more of flying the KE, rather than doing the maneuver. And not to be forgotten, the airfoil HAS to be symmetrical to fly 3D maneuvers well. Next in line would be the CG. This is more critical than anything else for good 3D abilities next to having enough power to do them. The 3D CG is usually 30-40 percent of the wing chord as measured back from the wings leading edge at the root. The components of the airframe also need to be situated so that the CG is not only balancing the airplane fore/aft, but in the lateral (side to side) and vertical (top to bottom) plains as well. Centered as close to the middle and at the thrust line as possible. It likely cannot be perfect, but it can get very close. Your plane needs to be balanced so that it will fly hands off at half throttle (50% power) upright or inverted (upside down) without the need for elevator trim. It should feel very neutral and somewhat buoyant if the CG is correct. When properly balanced your plane should fly with only VERY minimal, in any trim inputs, strait and level, RSU or inverted at half throttle. Next come the ailerons. They need to be very wide and extend from the root to the tip, if not you will not get good prop wash over them and they will be stalled along with the wing in high alpha attitudes. They need at the very least 45*of throw, but about 60* is the norm for a good 3D plane. The tail moment (length of the tail fro the wing’s trailing edge to the horizontal stabilizer’s leading edge) is next. 3D planes are usually short coupled, meaning the tail moment is short. If the moment is too long it will not flip and pitch fast enough, or at all which will make most all 3D tricks UN-doable. But if the moment is too short it will be so sensitive to pitch changes that it will be too hard to manage in most maneuvers even for a competent 3D pilot. A good “rule of thumb” for the shortest tail moment would be about the length from the prop to the CG, any shorter and it may be too short. Next is the fuselage inside the tail moment, which isn’t a big deal, but having a tall back, like a turtle deck, gives the plane more fuselage area to “fly” on during knife edge (KE). Last but not least would be the tail feathers. The stabilizers should be attached very well but not be too large as compared to the size of the control surfaces. If they have too long of a chord they will do more to slow the rotation of the plane rather than aid it. Some 3D airplanes don’t even have any horizontal or vertical stabilizers. The elevator and rudder are “flying” in that they are hinged on a pivot on the fuselage. The whole horizontal or vertical stabilizer will move! This is something really cool, but not required at all. The control surfaces, both rudder and elevator, have to be quite large with at least 45-60 degrees of throw. Anything less and it will be very hard to do most 3D maneuvers. For good KE the horizontal stab must be very close to in-line with the wing or just below it for low-coupling. The rudder does need to be large, but not too tall. If the rudder is too tall or has too much counterbalance the rudder could roll the airplane as much as make it yaw, which would make KE and lots of rolling maneuvers very hard to do because it would tend to over roll the airplane, but not roll it enough so that the ailerons wouldn’t be needed. You’d be fighting with the ailerons to counter the rudder’s roll effect rather than make the airplane roll axially. Keep all these in mind when searching for your 3D airplane.
As a competent pilot you have to be able to control your aircraft at all speeds and attitudes with all four controls, The aileron, elevator, rudder and throttle. Without than ability, learning 3D will never happen for you. You have to be a “two stick” pilot in that you HAVE to know how to fly an airplane with all four controls, where as most sport/Sunday fliers rarely use the rudder or manage the throttle. They just nail the throttle on takeoff, hoping it the takeoff is quick so it doesn’t get “squirrelly” then they bank and yank until they are out of fuel or get board, then chop the throttle and head for what they hope is the middle of the runway and fly the airplane to the ground, hopefully onto its wheels during all three or four bounces/skips before it rolls to a stop either at the end of the runway or off the side. Sound like you? Well, try flying around using your left thumb before you try some 3D. Even the most basic 3D maneuvers and tricks take good rudder coordination. To gain a quick sense of using the rudder, fly your trainer or most basic sport model making good use taxing the model, making long takeoff roll outs before lift off keeping the model down the center of the runway using your rudder. Make coordinated turns and circles. Try some flat turns, where-in you fly in a circle while keeping the wings level the whole time with your ailerons but using your rudder to make the turn. Try some forward slips and maybe some knife edge. After you’ve got confidence in flying those maneuvers concentrate of cross-wind landings, forward slips to landing, and then graduate yourself to rolling circles. Practicing rolling circles will really aid you in learning to coordinate all three controls and will progress you easily into rolling harriers and rolling loops!
After getting friendly with your left stick and rudder anyone can now teach themselves to fly 3D! But first you need a good model. Not just a good 3D capable plane, but one that is cheap and durable. The best way to go is either with a FFF or EPP foam airframe, like Twisted Hobbys Crack Yak or Crack Pitts , All are very good 3D trainers and super cheap and can be flown with very in-expensive gear. Just like learning to fly, you WILL crash! Just stay at a comfortable altitude and done be afraid to bail out of a maneuver early or just “pan-cake” on the ground. Keep some hot glue or CA around! ; )
Most 3D maneuvers are not specifically derived from standard aerobatic/IMAC maneuvers. They are a breed of their own but a good knowledge and ability to execute standard maneuvers will help to say the least. I’ll list the known 3D/Freestyle maneuvers starting with the easiest to the hardest to perform.
Harrier - A very slow forward flight motion with a high Angle Of Attack. One can fly strait or circle using the rudder to turn the desired direction and opposite aileron to rudder to keep the wings level, using throttle to maintain the desired altitude. Find the AOA your plane likes best, which is where you still have aileron control without the wings rocking back and forth.
Inverted Harrier - The same as the above, just inverted. Most capable pilots find this easier than a standard harrier due to the wing being above the CG. It tends to have less wing rock, but your rudder and aileron inputs are reversed, and there is a fair amount of “pucker factor” seeing your plane’s tail so close to the ground and the landing gear above it.
Elevator - This is just a descending harrier. You can make it as steep or gradual as you are comfortable with by using your throttle, again find a good AOA where the wing doesn’t rock. This can also be done in Knife Edge or as a rolling harrier!
Flat Spin - A spin induced with full elevator, full rudder, and aileron. Once the spin is initiated you will level the wings with the ailerons and increase engine speed a bit to pull the aircraft around. This will in turn flatten the spin. The wings HAVE to be FULLY stalled to get a good and level axial rotation. Not necessarily a 3D maneuver by most 3D pilot‘s definitions, but you have to know how to do one properly to do some 3D maneuvers.
Knife Edge Spin - Its easiest entered from a vertical climb. Add full LEFT rudder at the top just before the stall and let the plane rotate 270* then apply throttle and full down elevator, your plane might require aileron input as well to keep the wings perpendicular to the ground. This will throw you into a type of falling lomcevoc where in your plane is tumbling over its pitch axes. Its just a flat spin turned on its side. Manage your power to make the spin as slow or as fast and violent as you want.
Hover/Torque Roll - A hover is a controlled prop-hang in that you are holding your airplane vertically without any apparent movement or motion, forward, backward, sideways or up/down. You pull the aircraft into a completely vertical attitude and allow the propeller to hold the airplane in the air like a helicopter. One can keeping the wings from spinning by adding right aileron or just let the plane spin on its own because of the torque from the prop, which is a torque roll. When first learning most pilots find it easier to induce a slightly faster spin/roll. This will minimize the time the belly is towards you, which is that hardest part of hovering/torque rolling.
Wall and Alien Wall - The Wall maneuver is where your plane starts from a horizontal flight path and immediately transitions 90* into a vertical climb, as if it were rolling along the ground and hit a wall and started to climb the wall. An Alien Wall is the same only much more violent (like a “UFO” sometimes seems to do) in that it is entered with much more airspeed and G. This maneuver is usually immediately ended in a hover or a waterfall.
Pin Wheel - This is a simple maneuver but it requires a lot of power and very rearward CG and a ton of rudder to complete properly. Start from a hover, yaw to the right a few degrees then simultaneously add full right rudder and full power to complete at least one full axial rotation around its CG as if the plane were stuck onto a pinwheel and spun. Some aileron input might be needed to keep the plane from falling out into a flat spin and a touch of down elevator can make it rotate a little faster.
Snap/Pop up ! - The Snap-Up is when the airplane comes to a hover from a horizontal flight path with a snap-roll in the middle. Basically a wall with a snap in the transition and ending immediately in a hover. Try not to over rotate the snap roll, just initiate the snap with the usual full elevator, rudder and aileron but half way thru the snap neutralize the elevator then stop the rotation by neutralizing aileron and rudder, then pull full up with a burst of power to finish the vertical transition. It reads harder than it actually is. A Pop-Up is the same maneuver only without the snap.
Waterfall - The waterfall is a maneuver where the plane pivots 360 degrees over it’s pitch axes with very little forward motion and altitude change. This maneuver takes either a lot of power or inertia to complete. It can be finished with just one flip/rotation or multiple rotations. It is usually done “on the outside” with down elevator which is easier because its not fighting prop torque.
Yo-Yo - Entered from a hover or wall, power out vertically to gain some altitude (not too much) then enter a ½ waterfall. The plane will flip around into an inverted elevator, let the plane fall back to the ground and power up and do it again. This maneuver looks best doing it two to three times making the loop smaller and lower each time, ahh…like a Yo-yo!
Falling Leaf/Tic-Toc - From altitude enter this maneuver from a roller coaster, harrier, hover, or just slow the plane to a forward and level stall. Push the plane over onto its back with a burst of power, then immediately onto its belly with another quick and hard burst of power. Do this several times in a row, like a leaf flopping slowly to earth from a tall branch. Try to keep the plane parallel to the ground so you don’t over rotate into a waterfall. You may need to use right rudder with the throttle bursts to keep the plane strait.
Pogo - This is another hovering maneuver. Rapidly climb and then descend (tail slide) in a hover as if the plane were riding a pogo stick! Its most often done in a hover, but some better than I can do a torque rolling pogo too!
Snap Rolls -The snap roll is commonly used when flying 3D so I will add it to the list. The Snap Roll by AMA aerobatics code definition is "a simultaneous, rapid auto-rotation in the pitch, yaw and roll axes in a stalled wing attitude." Now, to do a snap roll there are some things the plane must do.
1. You first need to sharply increase the angle of attack to put the plane into a position where it will stall without changing the track (much) This is easier said than done but a little nose break is really necessary to get a good snap and hold your line. This is done with a quick pulse of up elevator to "break" the nose and put the wing in a position to stall.
2. Within a split second of that pulse of elevator input you push the rudder full over (to start learning to snap) and at the same time input full aileron deflection in the same direction as the rudder.
**What you should see then is called "rapid auto-rotation". When you input the rudder you get "YAW" which means one wing speeds up, and the other slow rapidly and stalls. This initiates a sharp roll in the direction of the rudder input because one wing stops flying. Technically you should not "Need" to use ailerons, but with RC models the ailerons help to get the process started. You should not be depending on the ailerons for the rotation, if you are its not snapping they are just there to clean it up a little.
3. To keep the plane on heading as stated about you neutralize the elevator 1st and then the ailerons and rudder. All of this happens in less than 1 second.
Again,
Initiate stall in the wing by sharply pitching.
Stall the wing by inputting the rudder
Ailerons to clean up the rotation.
Neutralize at just the right moment to stop roll.
It is sort of a J pattern laid on its side.
Tail Slide - Bring the plane into a vertical climb/hover then reduce the throttle to below that at which the plane hovers and by controlling the slide backwards strait down with backward control inputs bring it back down to its starting altitude or below that even. It is very hard to do and nearly impossible to complete if you chop the throttle completely because there will be no prop wash over the surfaces to keep the plane from toppling over nose first.
Harrier Roll - Like the Harrier maneuver only roll combined and performed simultaneously in flight. Its not so hard, it just takes a little practice to get the pattern down. If rolling to the left use LEFT aileron and begin the pattern of RIGHT rudder, DOWN elevator, LEFT rudder, UP elevator and repeat. After you get the pattern down you can “come in” a little early on the pattern to get the plane to harrier roll in a right hand circle or one can come in late to make a left-hand circle. Most pilots find it easiest to continuously bump the throttle during the maneuver to keep the roll rate and altitude under control.
Rolling Loop - Using the same technique as the rolling harrier add full power to make your up-line and pull the power back as needed to make the top of the loop round, on the down side you’ll have to get over the pucker factor and really work your thumbs because you’ll have to apply near full power again on the last quarter of the loop to get it to come out and not smash into the ground, but too much and it will come out of the loop too quickly and the loop will not be round.
Parachute - This maneuver is a vertical diving roll that virtually stops its descent as it instantaneously enters into flat upright position. The transition has to be very quick so that the inertia continues to push the plane strait down (as if it deployed a parachute and it floating down) instead of flying out of the maneuver in an elevator.
Panic - The Panic is simply the parachute maneuver only ending with the plane inverted and much closer to the ground.
Blender - This maneuver is like the previous only ending in a flat spin. I’ve also seen it done ending in a KE spin instead of a flat spin.
Blaino Draino - Start from straight and level, pull vertical to a fair altitude and chop throttle, pull full elevator to flip back over for a vertical plunge. Roll the plane until your close to the ground then quickly stop the roll about 1 mistake high and pull full up elevator with full power all at the same time making the plane instantly transition into a harrier with rudder getting very close to the ground. It can be exited immediately into a hover or waterfall, or any maneuvers that start with a nose-high attitude.
Roller Coaster - This is basically a horizontal falling leaf, starting from slow level flight pitching the airplane strait down then strait back up then strait back down again. If you enter it with too much forward speed you will over rotate and into a waterfall, not enough speed and you’ll not have enough forward inertia to make at least one down, one up and one down pitching sequence before your plane is no linger moving forward.
Terminator - Its when the plane is flying straight and level and then makes a sudden 90* dive straight down. When the plane gets close to the ground pull out suddenly and fly out of it with full power, think of the exit as a wall on its side, the ground being parallel and only a couple feet below the imaginary wall your driving you plane on.
This is just a selection of 3D manoeuvres there are many more out there that are signature moves of professional RC pilots or combinations of these. Like everything in life and especially in this hobby it all just takes practice. Set a goal for each ~10 minute flight to learn ONE maneuver and become confidant with it before moving onto another. Once you feel comfortable flying all these moves try stringing a few together in one short sequence of 3 or 4 tricks. After you can do all 3 or 4 in a row consistently try adding a couple more at a time until you have a 4 or 5 minute routine put together! This is very fun and as challenging to do as it is to learn the moves themselves. Note that no plane can just jump from any one move to another! A 3D pilot has to manage his airspeed and airspace so that too many G’s aren’t pulled or so you don’t drive right into the dirt! For example you can’t go from a panic strait into a falling leaf or you’ll fly right into our archenemies, the earth! Try doing a rolling loop into a wall, then into a tail slide. Or try a wall into a waterfall, then into an inverted harrier. Do not enter a violent maneuver with too much forward speed, for example a panic with too much throttle on the down-line. When the plane reaches the point of the transition it will either over rotate or you could just blow the wings right off. One can’t enter a quick maneuver without enough speed/inertia, which will likely only have the consequence of not being able to complete the maneuver and making you look bad. Unless you are too close to the ground, for example; you do not have enough airspeed to finish the bottom of a rolling loop, try splicing maneuvers together as well, sometimes called 3F, or Flip Flop Flying. Cut maneuvers short or in half and immediately transition into another, for example: A half rolling loop into a Terminator at the top, then throw in a falling leaf or harrier roll at the bottom of the Terminator. Keep the “down time” or “setup time” between maneuvers minimal. This will keep your adrenaline, heart and your thumbs pumping and the peanut gallery on their toes!
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