Aerobatic's

Introduction.

Once you have learned to take-off, fly around a few circuits and land you will almost certainly want to 'explore the envelope'.

Now is the time to start some basic aerobatics, particularly if you have moved on from a basic trainer.

Have a look at the kind of aircraft more suitable for learning aerobatics. While a basic trainer is capable of flying many of the manoeuvres shown, an aerobatic or good sports model should be capable of flying them all easily.

The two main aerobatic manoeuvres are the loop and the roll , the majority of all other manoeuvres being some combination of them. In all the illustrations below, the manoeuvres are carried out into the wind direction as this is the easiest way to learn the new manoeuvres.

Aerobatics have a universal set of readily understood diagrams named after the Spanish pilot Aresti which we will attempt to explain just some of the basic manouevres - there are over 800 recognised manouvres! Any aerobatic schedule can be broken down into a set of manouvres, which in turn can be broken down into their constituent components - for example, an Immelmann Turn is a half loop followed by a half roll and so on.

Firstly, a word of warning!

Make sure that you attempt any new manoeuvre three mistakes high. Having plenty of height gives you a lot more time if things get out of control. Remember that you are now going to see your model at a load of unaccustomed attitudes. Generally, you can fly low and you can fly slow, just don't do both at the same time: Out of speed, out of height and out of ideas!

A quick note about the drawing convention used in the diagrams. The model shown is red on it's top surfaces and yellow on the underside. The flight path is represented by red corresponding to the top side of the model while blue represents the underside. The wind direction arrow shows the direction from which the wind is coming.

On with the fun!

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Aresti Diagrams

These are the most basic manouevres commonly used and, where applicable, we will show them throughout our Aerobatic Guide.

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High Angle Of Attack.

Perhaps the most useful flying 'trick' is flying at low speed, high angle of attack (AOA) or high 'alpha'. With a bit of practice, most model aircraft can be made to hover in fairly low wind speeds. The best way of achieving this is to turn straight into wind, close the throttle and try to maintain the same altitude using the elevator. Since you have cut the power, the model will slow down rapidly and go into a nose-up attitude. Now comes the balancing part. Gently use the elevator to increase or decrease the nose-up attitude, and the throttle to maintain height. The model will tend to stay pointing into wind but if it starts to drift off-wind, gently use the rudder to correct. With a bit of practice, you should be able to get the model to hover. If things start to get out of control, decrease the elevator and increase throttle to drop the nose and gain speed. You can then go round and try again.

Nice trick... but what's the use?

Well, the model doesn't know whether it's a couple of hundred feet up or a couple of inches. This is a nice way of really slowing up your model for approach and landing.

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The Loop.

Anyone can open the throttle, pull in up elevator and go over the top for a loop. Getting the loop circular is definitely not as easy as it would seem.

Ensuring that the wings are level, head straight into wind at about three quarters power and pull in elevator. As the model approaches vertical, go to full power and decrease elevator slightly. As the model approaches the top of the loop, cut throttle completely and release the elevator. The model will 'go ballistic' over the top of the loop. You may even need to input some down elevator to maintain the correct arc. As the model passes the vertical (this time heading straight for the ground!), ease in up elevator and open up the throttle again to level out.

It is impossible to be specific about exactly where in the loop certain control inputs are made and how large they should be. This depends on the specific aircraft being used and wind conditions. If you are trying to loop across wind, rudder will have to be used to maintain position throughout the loop. The main thing to remember is that the well executed loop is an exercise in throttle and elevator control.

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Axial Roll(s).

The axial roll is one of the easier manoeuvres in that just about everyone hits full left or right aileron and hey presto, a roll. Usually, the exit from the roll is nose down so attempting a second roll results in either a few seconds of frantic stick wiggling or removing the model from it's newly created hole in the ground.

Enter the roll straight into wind with lots of speed and power and wings level. As the model rolls inverted, apply some down elevator and then release the down elevator as it passes the inverted position. Continue to roll until the wings are again level. No problem! Again, the amount of down elevator you have to apply will depend on the type of model you are flying. A trainer will require much more down elevator than a purpose built aerobatic machine for example.

If you practice this you will soon notice that the model is going more slowly after a single roll. This is because the control inputs over the roll result in an increase in drag. Should you now attempt a second roll or more, the control inputs you have to use will be correspondingly larger to maintain altitude and roll rate. With some practice, you will soon be able to continuously roll from horizon to horizon - with hardly any panic at all! One thing to remember is to practice rolling in both the clockwise and counter-clockwise direction.

Don't become 'handed'.

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Inverted Flight.

Inverted flight is pretty straight forward provided you remember that up is down and down is up as far as the model aircraft is concerned. Because your model will be trimmed to fly 'hands off' when right side up, when the aircraft is inverted, it will have less available lift to hold it at the same altitude. This needs to be compensated for by using down elevator to hold the nose up. Maintain the down elevator to hold the inverted attitude and altitude. The amount of down elevator required depends on the aerofoil of your model.

To start, heading into wind with wings level and about half throttle, half roll to inverted and hold the nose up with down elevator. Half roll again to come right way up. Don't recover by half looping, particularly if you're getting into difficulties, as speed will rapidly build up and height will rapidly disappear!

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The Bunt.

Otherwise known as an Outside Loop, this is a loop which pulls negative g compared to a normal loop which pulls positive g. Normally, this is done by diving towards the ground initially but for first practicing this manoeuvre, we suggest you go upwards first. For a given size of loop, more down elevator is required for a bunt than up elevator is required for a normal loop. Both types of bunt are shown.

This manoeuvre is best practiced going downwind. The reason for this is that once you are about halfway round, the wind direction 'helps' the model climb through the second (top) part of the bunt.

To get a feel for using down elevator in a bunt, we recommend trying this manoeuvre first. This is really a normal loop but instead of entering and exiting the manoeuvre upright, the model is rolled inverted and a negative g loop is flown. The advantage of this is that the model goes up first so your margin of safety improves. A real bunt offers the thrill??? of being inverted, heading for the ground and at no great height. The resulting hole in the ground can be impressive! Going UPWIND , with wings level and at about half throttle, half roll to the inverted position. Open the throttle and push in down elevator to start the loop. Flying through the loop is exactly the same as for a normal loop except that down elevator is used instead of up. When the bunt is complete, half roll to recover.

Now for the true bunt. Gain plenty of height before starting this manoeuvre. Head DOWNWIND .

With wings level, completely close throttle and push in some down elevator to start. As the model approaches the vertical, increase both throttle and down elevator to go through the bottom of the bunt. Open the throttle fully to climb. As you pass the vertical, decrease down elevator as gravity will help to round off the bunt.

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The Immelmann.

This manoeuvre originates from the First World War and was the first to fully use the three dimensional ability of aircraft. It was used to get behind an enemy aircraft flying in the opposite direction - an aggessive manoeuvre. The basic manoeuvre is a half-loop followed by a half-roll - in effect, the manoeuvre swaps speed for height and a 180 degree change in direction.

Start wings level as if executing a full loop and when you reach the top, immediately half-roll to the left or right, opening the throttle to regain speed.

A variation is the quarter-loop, half-roll, quarter-loop then another half-roll. This loses speed, gains height but does not change direction. Sounds complicated but the diagrams should make this clearer.

Start as before but when you have completed a quarter-loop, immediately half-roll then quarter-loop. You finish up inverted at the top so half-roll again to exit straight and level.

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The Split S.

This is effectively the reverse of an Immelmann and is a usually a defensive manoeuvre. It's a half-roll followed by a half-loop. The benefit of this is that height is exchanged for speed and a change in direction - a good move for breaking off aerial combat and heading for home! Remember to chop the throttle in the first part of the half-loop otherwise the turning radius is big.

Just as with the Immelmann , the Split 'S' can be modified by introducing a half roll halfway round the loop.

Firstly, half roll inverted, cut the throttle completely then pull on up elevator to start the first quarter loop. When the model is vertical, release elevator and half roll. When the half roll is complete, again pull on up elevator to perform the second quarter loop. As you reach the bottom, increase throttle and level out.

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The Reversal.

The Reversal is another method of reversing your direction but recovering at the same altitude as the start of the manoeuvre (unlike the Immelmann and Split 'S').

The first method is to execute a partial (in fact 5/8ths) loop, half rolling to an upright 45 degree diving attitude then finishing by levelling off (a 1/8th loop) at the entry height.

The second method is to pull up into a partial (1/8th) loop, half rolling to an inverted 45 degree climbing attitude then finishing by executing a partial (5/8ths) loop to level off at the entry height.

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The Stall Turn.

This manoeuvre is useful for reversing the model aircraft's direction and leaving it's speed and altitude pretty much unchanged on completion. It looks pretty as well if properly executed.

Pull in up elevator as if starting a loop with half throttle. When the model is vertical, release the elevator and completely cut the throttle, keeping the model heading straight up. It will soon run out of speed. When it stops, immediately input full left or right rudder and add a short burst of throttle. The model should then pivot about it's centre of gravity. When pointing vertically downwards, add some throttle and pull in up elevator to pull out in a quarter loop - following the route the model took on the way up. The important thing with a stall turn is to make sure the the model is stopped at it's highest point and that it pivots about it's centre and not the wing tip. The model should follow a 'return' path which is identical to the upward route.

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The Spin.

This manoeuvre is pretty unique in that it depends on the model aircraft being deliberately stalled. For once, the model is leading in the manoeuvre - ie. you wait for it to do something rather than the other way around.

First, gain plenty of height and head into wind. Cut the throttle completely and use up elevator to increase the angle of attack without allowing the model to climb. The model will slow down pretty quickly. You now have to wait until the model stalls. By this time, you will probably have full up elevator on, trying to maintain height and the model will be in a high nose up attitude. When the model stalls, the nose will drop. Now input full rudder and the model will promptly go into a spin. Do not use ailerons to 'trigger' the spin - a common fault with a lot of fliers doing this manoeuvre. Hold on full rudder and elevator as the spin progresses. The number of turns in the spin is up to you but remember that it takes a good amount of height to recover. To recover, centre rudder and elevator then use down elevator to push the nose down, open the throttle to gain airspeed then use up elevator to quarter loop to exit the manoeuvre.

It may be that your model, rather than spinning, will go into a long, lazy spiral dive. This usually indicates insufficient rudder and elevator control movements or that the centre of gravity is too far forward. Try increasing the control throws first and if that doesn't work, gradually move the centre of gravity rearwards -about 6mm. (1/4") at a time.

On most models, rather than the nose dropping at the stall point in which both wings stall at the same time, one wing will drop. In this case, you yaw into the dropping wing - ie. if the right wing drops first, use full right rudder and vice versa.

You should aim for a complete number of spins so that the model recovers pointing in the same direction that it entered the spin. Recovery from a spin is entirely dependent on the model type and may take anywhere from virtually instantaneous recovery to a further half turn in the spin.

In a very few cases, a model will not recover simply by centring rudder and elevator. If yours won't, use opposite rudder to the spin direction and use full throttle. As soon as the spinning stops, get the nose down to regain airspeed and pull out.

So far, all the manoeuvres carried out have made little or no use of rudder. Now's the time!

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The Knife Edge.

This is how an aircraft is not meant to fly!

In this manoeuvre, the wings provide no anti-gravity support! The only thing keeping the model in the air is the lift provided by making the aircraft's fuselage generate lift, firstly by rolling the aircraft onto it's side then using the rudder as an elevator. Normally, the teardrop-shaped fuselage generates a balanced side force (well, it does if it's straight) but using the rudder forces the fuselage into having a positive angle of attack to the airflow.

This is also a manoeuvre in which things can go wrong very, very quickly! If there is only one thing you remember, make sure it's that the rudder goes in the opposite direction to aileron ie. Roll Left, Right Rudder and Roll Right, Left Rudder - repeat after me - Roll Left, Right Rudder and Roll Right, Left Rudder! Since this is a high drag manoeuvre, you'll need plenty of power.

To start, use full throttle, quarter roll using ailerons and quickly apply opposite rudder. Hold the model in knife edge for as long as you want (or can!) then release rudder and quarter roll back to level.

It's about now that you find out how unstable your model aircraft really is! A number of things are likely to happen and only one of them is a good Knife Edge!

 

1. The model will want to continue to roll, either with the initial roll direction or against it. This is because there is cross coupling between the ailerons and rudder - "techie term" - yaw induced roll. This can be cured by using the ailerons to control the roll, mechanically ie. you do it -electronically mixing appropriate aileron trim with rudder ie. your transmitter does it or you take a hacksaw to the wings and adjust the dihedral angle - ie. the model does it! This is the most common problem in knife edge. A good aerobatic aircraft will have very little coupling while a trainer (Why are you trying to Knife Edge a trainer?) is not so good.

    

2. The model will want to pitch nose up or nose down. Again a function of the design, the best bet is to use function mixing if you're lucky enough to own a computerised transmitter. Otherwise, you'll just have to apply the required amount of elevator.

    

3. The model will not maintain height. This next major problem's solution is real vague! Either too much rudder has been applied and the drag is too great to maintain speed, insufficient rudder has been applied to get the angle of attack high enough or the model doesn't have enough power - take your pick! Try experimenting with the amount of rudder applied first then more 'grunt up front'.

    

4. All of the above - Stop Knife Edging your old trainer!

    

5. The model will quickly gain height in Knife Edge and threaten to loop. You lucky, lucky git! I've wanted a model like that for years! You have excess power, excess rudder control - it's perfect! To Knife edge, back off power and rudder on your next attempt.

If you are getting into difficulties, release the rudder, chop the throttle, roll the wings level and use elevator to pull out of the dive which you will inevitably be in. I speak from experience. Do not try using the elevator and aileron with rudder on otherwise you'll be practicing the equally spectacular Flick Roll!

Practice Knife Edge passes rolling both to the left and to the right. You will probably find that the controls you have to input vary slightly depending on the roll direction.

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The Four Point Roll.

Once you have mastered the Knife Edge and Inverted Flight , you can use these manoeuvres for a four point roll.

The Four Point Roll is an Axial Roll but the manoeuvre is interupted at each quarter roll point.

Enter the manoeuvre with plenty of speed and power and quarter roll into knife edge. If you roll to the right then input left rudder to hold the nose up. Try and keep the knife edge straight and at constant height. Hold this position for a moment then continue the roll to the inverted position with another quarter roll and hold in down elevator to maintain height. Again after a moment, execute a third quarter roll to go into knife edge and hold. Note that this time, the direction of rudder input is the same as the rolling direction ie. if you are rolling to the right, then input right rudder. This makes sense because, for example, three quarter left rolls equals one quarter right roll. Finally, quarter roll to upright.

The co-ordination required for this manoeuvre is fairly tricky to learn and requires a fair amount of patience (and a lot of height!).

Briefly, the control inputs required for a clockwise and anti-clockwise Four Point Roll are:

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Humpty Bumps

The Humpty Bump is a rather bizarre name for one of the most useful and versatile aerobatic manouevres around.

It can be used on the centreline of a display box or at either end and can remain inthe display plane or shift the model inwards or outwards - cross-box.

At it's most basic, the Humpty Bump consists of a quarter loop into the vertical. On the way up, the model is half rolled. A half loop at the top results in the model coming vertically down where a half roll is executed followed by a quarter loop to pull out. The quarter loops should be the same radii but do not have to be the same as the top half loop. You can also do two quarter rolls on the way up and down for the same effect.

This is where it starts to get interesting!. Omit the downwards half roll and you have a straightforward turnaround manouevre.

The next step is to replace the half rolls with quarter rolls. If you do this, you will force the model outwards or inwards. The quarter rolls should be in opposite directions. If the first quarter roll had been to the right, instead of to the left as shown, the top of this humpty bump would would be a "push over the top" - a half bunt - instead of a half loop.

Similarly, you can initially quarter roll the opposite way on the way up to bring the model closer in.

These are just four of the many basic variations of the Humpty Bump. There are many variations of these depending on the choice of quarter roll diections. Experiment yourself and see just how versatile this manouevre is for inline and cross box manouevring. You can even do a turnaround crossbox manouevre where the model recovers upside down - simply do the two quarter rolls in the same direction.

The rest is - experiment!

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Cuban Eights

The Cuban Eight is a fairly standard aerobatic manouevre and is not particularly difficult. It does however require a lot of practice to get it spot on.

The idea is to do two circular manouevres, one upwind and one downwind of the pilot's stance. The central part of the manouevre is the crossover where the model rolls from inverted to upright. It requires considerable practice to get a good cross over, down the 45° lines and in the centre.

You can see immediately that the model must pass the centreline before the model is pulled up for the first circle.

A very common manouevre is the Half Cuban Eight and is usually used as a turn around end manouevre. Only one half of a Cuban Eight is carried out (Duh!) with themodel reversing it's direction from the entry position. If used as a turnaround, the whole manouevre is displaced to the left or right and is usually followed by some kind of centre manouevre - a loop for example.

If you can do something one way then you can usually reverse it! Much the same as a Cuban Eight, the Reverse Cuban Eight is no more difficult. This time however, you have to start the manouevre before you reach the centreline.

The Half Reverse Cuban Eight has a major advantage over the standard Half Cuban Eight for a turn around. You finish the manouevre much earlier - and so further away - with the wings level which gives you a good run in for any following manouevres. This is a highly recommended means of turning the model around.

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Slow Roll

The Slow Axial Roll Is one of the most attractive manouevres that you can do with a model aircraft. It is also one of the most difficult! As such, it merits a page all to itself!

Although superficially similar to a Four Point Roll - the stick deflections and senses are identical - the Slow Roll demands smooth transitions in the use of elevator and rudder as you progress through the roll.

A typical roll rate for an aerobatic model is around 360° per second. Compared to the average sports model, this rate is slow. To execute a slow roll, you should be trying to get down to 60°-70° per second which means that a slow roll should take 5 or 6 seconds - not long until you try to do a roll in this time! A good slow roll also eats up a lot of sky.

Half the problem in being able to execute a good slow roll is having a well trimmed model. If applying rudder causes your model to pitch up or down or roll with or against the rudder, you are not going to enjoy much success. Ideally, you want your model to be completely "uncoupled" so that rudder only causes yawing, aileron only causes rolling and elevator only causes pitching. If it also flies with no down elevator when inverted - read on!

To achieve a very low roll rate you may want to consider using the low rate aileron on your transmitter for slow rolling only. It is very important that you watch the model very carefully throughout the roll and make any minor corrections as the roll progresses.The hard part is maintaining direction and height. Initially you will find it hard to really slow the roll down and to make it look smooth - all it needs is tons of practice.

You need to start a slow roll well away from you as the intention is that you will have completed half the roll as the model passes in front of you inverted.

Start the roll with a small aileron input which will remain constant thoughout the roll. In the first quarter roll, the model will progressively want to fall down the downgoing wing. This you correct with a progressively increasing amount of opposite rudder until it goes through it's knife edge position. (Right roll, left rudder and left roll, right rudder)

As the model continues to roll to the inverted position, you have to slowly release the rudder that you've just input. The model will progressively want to drop as it nears inversion so you have to gradually input down elevator to correct this.

Half way there! Hopefully the model is now inverted and right in front of you!

Continuing through the roll, you gradually reduce the elevator and feed in the same rudder as the model approaches knife edge again. (Right roll, right rudder and left roll, left rudder)

As the model passes through the knife edge, gradually release the rudder until you are back in level flight.

As said before, this is not an easy manouevre. If you've seen an expert do a truly slow roll - horizon to horizon - it is impressive!

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Vertical Eight

The Vertical Eight is another fairly standard aerobatic manouevre and is not particularly difficult. It does however require a lot of power.

The idea is to do two circular manouevres, one above the other, with both having the same radius, directly in front of the pilot's stance. The central part of the manouevre is the crossover.

The Vertical Eight shown has no included rolling manouevre and so the bottom loop of the Eight is an inside Loop while the upper part is an outside loop or Bunt. Generally, the Vertical Eight is executed while heading upwind.

A common variation of this is to incorporate half rolls at the crossover in both the ascending and descending parts of the eight. This results in both parts of the Eight being inside loops.

The new Gold schedule includes a Vertical Eight but unusually this begins and ends in the middle. In fact, this variant is simply a Loop followed by a Bunt on the centreline which should be clear from the diagram.

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Four Point Rolling Circle

For a change a nice simple and straight-forward manouevre! And it looks impressive!

Start off as if you're going to execute a standard circuit with the model directly in front of you. Obviously the model will be slightly banked over to do this.

When you have completed a quarter circuit, roll the model 180° - personally I find it easier to roll inwards as shown - so that the model is now (roughly) inverted and continue the circuit using down elevator.

At the halfway point, again roll the model 180° and continue the circuit using up elevator - as if nothing has happened!

At the three-quarter point, roll the model 180° so that the model is roughly inverted and continue the circuit inverted using down elevator. This is generally the trickiest part as the model is coming towards you inverted - scary for most people! There is also the Döppler effect to consider. This makes the engine revs appear to increase as the model comes towards you, making you think it's descending. It's easy sitting in front of a PC thinking "Yeah, Right!" - it's still scary!

Continue with the circuit and roll wings level as the model crosses in front of you to complete this manouevre.

You can alternate the roll direction at the halfway point, just to change things a little.

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Rolling Circle

And now for something completely different!

The first time I saw someone do a rolling circle - at the time, I could do two rolls on a good day! - I couldn't believe what I was seeing. Not many club fliers would even think about trying something like a rolling circle and although it's fairly difficult, it's not impossible.

Before trying this, you should be capable of doing rolls in a straight line. This manouevre is much easier to do with a slow roll rate rather than the much higher roll rates that many fliers use - you just don't have the time to get all the correct stick inputs in.

If you've got continuous rolls down to a fine art, you are probably aware that if you don't get the elevator timing correct the model goes off course. A rolling circle is simply getting the elevator timing consistently wrong!

Very roughly, you are trying to feed up and down elevator in when the model is in knife edge flight. The more smoothly this is done, the more circular the circuit. Hopefully, the diagram above makes this a bit clearer. The main thing is to watch the model closely as it rolls round the circle.

Once you start rolling, keep constant aileron and throttle thoughout the circle. You can then forget them and concentrate on elevator. As the model goes into the first quarter roll, feed in up elevator slowly to maintain height and to start the circuit. This will compensate for the model starting to drop due to loss of upward lift.

As the model rolls past the knife edge position, slowly decrease the up elevator and start feeding in down elevator until you have sufficient in to stop the model dropping as it goes to inverted.

Continue feeding in more down elevator as the model passes the inverted position. This will again maintain height and continue the circle.

Now start decreasing the down elevator as the model approaches the second knife edge position and start feeding in up elevator.

Simply repeat this series of inputs to take the model round the circle and stop rolling when the model is in front of you again.

The thing to remember is that, like continuous straight rolls, the timing of the elevator inputs is regular - a drumbeat up/down/up/down.

You will also quickly discover that this can all go horribly wrong! There are a couple of positions round the circle when your head will turn to mince.

Most reasonable fliers can make it about half way round the circle and then the model starts to drop. Very wisely, they stop rolling and save their model. Provided they have tried this with sufficient height, no harm's done. Generally with continuous straight rolls, you don't have to consider wind direction. In a circle, you do. When you're heading downwind, you will need to apply a greater amount of up and down elevator than you do heading upwind - the height is being lost heading straight downwind.

The second problem area - and this is true of all circular manouevres - is with the Döppler effect in the final quarter circuit. As the model approaches you - pretty much head on! - the engine revs appear to increase. This is associated by any sensible flier with a loss in height, even though the model is maintaining the same height. Combine this with changes in engine noise associated with the model rolling and it's no surprise that there is an uncontrollable urge to stop doing what you're doing! There is also the problem that at some point here, the model is going to be rolling inverted and coming straight towards you - a real problem with orientation

Both these problems can be overcome by carefully watching the model all the way round the circle.

There's no denying that mastering a rolling circle will take a lot of practice but it remains a very impressive manouevre. There's no substitute for a lot of practice and a lot of height!

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Rolling Loop

And now for something completely...... harder!

If you like living on the edge, this is the one for you!

It goes without saying that you should be very confident in doing rolling circles before you try this one out. Unlike a rolling circle which at least offers a regular series of control inputs, a rolling loop has nothing like this. The reason is because gravity has a major effect on the model airspeeed. It's similar to to difference between a circle and a loop.

As you climb in a standard loop, the airspeed bleeds off, reaches a minimum at the top of the loop, then increases again on the way down. You compensate for this by increasing the throttle on the way up then decreasing the up elevator and throttle "over the top" then increasing the throttle again on the way down. So far so good. If you are rolling at the same time, the rate at which you roll will decrease as your airspeed decreases and vice versa.

You've really got to try this out for yourself as there is no way to "tell" you what the timing should be as you go round the loop. However, we''ll try!

Pull some up and start rolling. As the model comes to the inverted position, you need to push in some down to continue in the loop. This is a lot more than you would normally use for inverted flight.

As you continue through the next half roll, you will have to input quite a bit of up elevator to stay on track. Since the airspeed and roll rate are decreasing, the timing for the application of up elevator is slightly longer than the previous use of elevator.

As the model approaches the top of the loop, the up and down elevator inputs are less than they were at the bottom of the loop.

Now it gets tricky! If you think about it, the model wil be upright or inverted as it rolls over the top. You must be watching the model closely here to know what to do next. If it is upright, then the next elevator input will be down. If it is inverted, the next elevator input will be up. This means that if the input slightly before the top was down, then you repeat the down - if it was up, you repeat the up elevator. This is confusing because your timing has to change. You also have to decrease the throttle over the top otherwise you're going to rocket down the second half of the loop.

Continue rolling down the second half of the loop but now the airspeed is increasing so the time between up and down inputs decreases as the roll rate increases.

As with a rolling circle, the last quarter is the scariest! This time the model is coming down - and fast and the Döppler effect tels you it coming down even faster. This combines with a need to get the up and down elevator inputs in even faster - a good reason for having a low roll rate set up. You also need to increase the throttle for levelling out - not an immediate impulse with a model rolling on the way down!

This manouevre is certain to take a lot of practice. The good thing is, if it's beyond your current capabilities, it'll all go wrong when the model is still on the way up - you'll not get to the top of the loop relying on luck for the control inputs!

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Rolling Circle And Loop

If you've managed a rolling circle and a rolling loop , try putting the two of them together!

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