Learning Tricks

	Learning Tricks last updated 1-1-2008
Back to Main Page	Nose-In Hover Inverted Hover Inverted flying Autorotations Piro-flip

In this section I want to talk about a technique that helps you learn some of the more advanced maneuvers...actually any maneuver. When you begin your first attempts, don't practice the maneuver, instead practice the bail-out. The bail-out is much more important then the trick because your first attempts are rarely going to be perfect. It's almost a guarentee that you will mess up, so knowing how to bail-out can save you from a crash that would cost you money, time, and discourage you from trying new things.
Note: If you have a computer simulator then practice a lot before you try it for real. One thing I stress is to use the simulator realistically. There's two ways to use the sim, game-mode and real-mode. It's nice to 'play' around but dedicate a lot of time to real-mode. What this means is treat it like it was your real helicopter that you don't want to crash. As an example, take for instance learning to fly upside down. If you flip over inverted and get out of control then just keep giving commands trying to get control while the helicopter is moving all around the sky, then that is game-mode. If however you flip over and if you lose good control, then flip out of it, then try again, this is real-mode. You are not only practicing the trick but also practicing the bail-out. So if you are practicing nose-in and you start to get in trouble, just sit it back down on the ground and try again.

Nose-In Hover
Read my page <here>

Inverted Hover
There are a couple ways to enter this. The way I did it was to do a forward half flip, but another way is to do a back fliip, left/right flip. Either way, the first several attempts you should only pause for a split second then continue the flip. This accomplishs two things, it gradually gets you more used to seeing your helicopter upside down and it trains you what to do for a bail-out. After the first several very brief pauses upside down, you need to try to hold it longer. Do this only on the times when you enter a stable hover. If you do the pause and the helicopter is not level, then continue the flip or roll then try again. On the times you get a stable inverted hover let it sit there until the helicopter drifts too much. So if the tail moves more then 15 degrees or the helicopter is going up/down/left/right then bail out of it. As you get more comfortable then when the helicopter does drift, try making a minor correction... be prepared to bail-out if you give the wrong direction. I recommend that if a large correction needs to be made, then just bail-out and try again. When you begin learning to make corrections just do this on the times it only needs a minor input. The more you practice, the longer you will be able to hold it upside down and the better you will get at making corrections.

The toughest part is getting used to which way to move the controls. I know it's difficult but try to get used to the controls being relative to the helicopter. In other words left is not left and up is not up, but instead think of it like pushing forward on the elevator stick makes the rotor go toward the nose of the helicopter. This is a constant, it never changes no matter what attitude the helicopter is in. One thing that helps me is to imagine the cyclic stick connected to the rotor head and the rotor head being a pivot point. It's hard to explain this in text but if you look at the photo and think about it you'll see what I mean.

Inverted Flying
There are a few ways that are used to learn this. The most common two that I hear is to do a half loop or half roll. This works for some, but I prefer working into it from an inverted hover. Here's why, say you do a half roll. As you can imagine the helicopter is traveling from one side of the field to the other and as it enters the half roll, not only do you only have a short time to get some practice in before it gets out of visual range, but also the perspective is constantly changing. I prefer to enter into an inverted hover then just like learning to do forward flight I work on doing figure 8's and stretching them out.

Autorotations
Ron Lund of Rick's RC has a good article <here>

Tip 1: Just as the skids touch down apply a small amount of forward elevator. This will help prevent the blades from hitting the tail boom on those not-so-smooth landings. What happens is if you hit a little hard the blade will be angle upward at the back and will not pivot out of place and chop the tail boom off.
Tip 2: Make sure the blades are not loose. You should be able to hold the helicopter on its side and with a bump the blades remain in position and not pivot down.
Tip 3: Forward air speed is very helpful for autos. It is good to learn autos on a windy day so you have the increased transitional lift from the wind but lower ground speed. On no wind days make sure you have good forward motion as doing straight down autos will not turn out so well.
Tip 4: When you are doing full down autos do not hang around in the positive pitch area. This will drop the head speed very fast. Around -3 to 0 is good. There is a sweat spot and you will know you are at it when you hear a fluttering sound from the blades as you descend.

Things to keep in mind to perfect the auto is that the more you use your cyclic, the larger the profile of the rotor through the air. I get up some forward speed then go to 0 degrees collective and centered cyclic and fly it in like a plane. If done right (and with a little wind) you won't add any collective until just after the flare. If you are trying to do long duration autos, this works for that too, but you may need to go to -3 or -4 to build up some more rpm before landing.

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What I do for setup when someone is just starting to learn autos is to first setup the Hold pitch curve so that it is the same as the Normal pitch curve with the exception of the top point. I make this 100%. Then I have them hover a couple of feet off the ground and flip the switch. You do not have to move the collective stick at all. The main point is to get use to flipping the switch. After they do this a few times I get them to add collective during the mini-auto keep it off the ground as long as possible. As they get comfortable I have them start the auto from waist height. Then the next step is to get a little forward motion just as you flip the switch. Do this into the wind and you will see you can keep it off the ground much longer. The two best tips I can give for learning autos is to not have the blades loose in the grips and to push a little forward elevator just as the helicopter touches down. You can mess up and land fairly hard without causing a crash if you made sure you held a little forward elevator just as it was about to touch down.
Okay so you started these mini-autos up a little higher. You can practice this up to ten feet. Around 15 to 20 feet you get into a zone that is more difficult. In this range you need to go to zero or -2 degrees so you do not lose too much head speed. However this is very close to the ground and you do not have a lot of time. So actually doing the auto above 30 feet is easier due to more time. Anyway at this point you are doing baby autos with just a little forward motion into the wind. If you are not comfortable with the nose coming toward you, you can still get some forward motion. Just start with the helicopter in a hover on the downwind side of you. Move the helicopter sideways in an arc around you. Ninety degrees from the starting place the wind will be blowing at the side of the helicopter. Move the rudder stick so the nose is into the wind and at the same time flip the hold switch. Don't forget to hold a little forward elevator just as the helicopter reaches the ground.
At this stage this is about all you can do until you get comfortable with flying in a circuit. Once you do then the setup will change a little. You need to have -4 degrees of pitch at the bottom stick position. You should already have this in normal flight mode if you are at the stage of flying in a circuit. So duplicate your normal pitch curve to the Hold pitch curve and again set the top point of the Hold pitch curve to 100%. Now do a circuit and just out of the turn when it is headed back at you practice doing a descent at a 45 degree angle to a hover a couple of feet off the ground. The idea is to get use to it coming down at this angle and positioning it just right so it lands by you. If the helicopter is coming from the left then I suggest landing five feet to the right of center out in front of you. This will put the landing part of the maneuver so that the tail is at you instead of the nose. Eventually it will be good to be able to land nose-in for spot landing contest but for now it will be more comfortable if it lands with the nose away from you. As you get use to this approach then at the five foot level flip the hold switch and land. Again just remember to hold a little forward elevator just as it sits down. As long as you can have some hang time just before touching down then you are doing it correct and can flip the switch from a little higher point during the descent. What I mean by hang-time is that if you can stop the descent and maintain a hover for a second or more then that is hang-time. You do not want to do the hang-time up high, this should be done under three feet. As you do the auto from a higher altitude it is good to understand the form of the auto. All of the action happens down below ten feet. Until then you are just working the elevator to maintain a level descent. The collective is left around -2 degrees. You can find that 'sweet' spot for the collective by slightly moving the collective stick up or down until you hear the blades make a fluttering sound. Maintain this descent to about ten feet. At this time you will pull back on the elevator slightly to flare the helicopter. This will transfer forward motion into head speed. Flare just enough to stop your forward momentum. At this point push forward on the elevator to level the helicopter. By this point you will be about waist high. Now start moving the collective up to set the helicopter down softly.

Pirouetting Flip
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Video: To see a video of this maneuver right click <here> and select 'save as'.

Tips: In-air boom strikes - I have seen several over the years in many brands of helis. The main key to preventing it is to have the blades tight. That alone is the largest factor. If the blades are not tight and you put too much collective and cyclic together the blades can pivot and then reach the tail boom. If you hear the rotor bog a lot then you are most likely using too much collective. And obviously if the dampers are worn that could be a problem as well but from my experience they have to be so worn that you feel slack around center when you move the grips up/down.

Tip2: For those flying a helicopter with a clockwise rotating rotor (as viewed from above) like the Raptor and T-Rex helicopters, do the pirouette to the left. The will take less power from the engine.

When I first starting learning the trick I wanted to know how to break it down into sections. After asking several I never did get a good answer. For the most part everyone just said practice on the sim and simple start doing them on the real thing. They would say which way to move the sticks but what I wanted was some way to gradually work up to the full maneuver. After thinking about this I came up with a plan. Here is how I did it.

1. inverted pirouette
2. half piro-flip from inverted to upright
3. half piro-flip from upright to inverted
4. Do #3 then one piro to stabilize then #2
5. Piece #2 and #3 together without the piro in between
6. Work on smoothing the two halves.

1. Start with an inverted piro, nose-left, at a medium speed (about 2 to 3 seconds to complete one rotation). Work on keeping the helicopter in place. It does not have to be precisely in one spot but if you finish the pirouette and the helicopter is ten feet from where you started then you are not ready for the next step. Doing a quick or blinding fast piro does not count. It really does not take skill for the helicopter to stay in place doing a really fast piro. This is not going to help you. Again the piro should take 2 to 3 seconds to complete one rotation. If you are trying yet have trouble keeping the speed of rotation consistent as the tail goes into and with the wind then it could be that the gain is not high enough on the gyro.

2. Start with an inverted pirouette. As the nose comes around to you add a little more (not much) negative collective and start your cyclic maneuver. You will move the cyclic forward then circle it over to the right then down and back to center. You can see this in the photo on the left. You will work on the speed you do this to sync it with the helicopter. The timing should be such that when complete the half circle on the cyclic stick the helicopter is upright, level, and nose-in. Before starting this I was concerned if I did not do it right that the helicopter would end up in some attitude that would disorient me. However I found that I could be way off on timing and the helicopter did not end up in some out of control situation. Once you can do this section of the piro-flip well enough that you are not gaining or losing a lot of altitude and the helicopter is staying in basically the same area you started the maneuver then you are ready to do the same thing but this time starting upright.

3. Start upright with a left rudder input. You will start the same cyclic maneuver but this time start it when the nose is away from you. And of course you will give positive collective this time. Also due to delays from your response time, the radios response time, the servos response time, and the rotors response time you will have to find the optimal starting position. Around five to ten degrees before the nose is straight away from you is the ideal time to begin the cyclic half circle input. After you get that half under control then work on piecing them together.

4. Start with an inverted one then once you get upright continue one full pirouette and if stable then start the upright half.

5. Eventually you will get your reaction time fast enough to piece the two halves together without doing the pirouette in between.

6. Finally you will work on doing continuous piro-flips which require full cyclic rotation instead of just the right half. This is when the maneuver will smooth out and really look kewel :) Here is a break down of the stick inputs: