How to do the perfect wing-over?

[Spikey]

Or to be more precise ...

I managed to get 20 minutes out with my Lazy Bee this afternoon, and it seems that I'm incapable of persuading it to do a really neat, tidy and predictable wing-over in the sense that I come out of it heading near as dammit back where I came from and at the same altitude I started the climb from

What should I actually be doing on the stick-wiggling front, in what order, and when?

[Martin Harris - Moderator]

Fit it with ailerons?

There's going to be yaw/roll coupling so unless you have ailerons (Lazy Bees that I've seen haven't) the only way to get anything half tidy would be to offset the entry to allow for the roll...

Edited By Martin Harris on 19/01/2015 21:44:30

[fly boy3]

Hi Spikey, loads of info if you google "wingovers" but it only mentions rudder. Could be full size. Cheers

[Biggles' Elder Brother - Moderator]

Er, well Spikey in a wingover you should not come out where you went in! You should come out slightly to the far side.

The basic wingover has several forms depending on how steep you make it. I think the actual FAI definition has the wingover performed at an approximately 45 degree bank. But it can still be a wingover even if the climb in is vertical and the bank effectively 90 degrees - which is what I suspect you are doing.

In a true wing over the aircraft should rotate about a point not in the centre - to look really neat that point should be at the inside wing tip, but that's very hard to do precisely so most folks reasonably settle for a rotation point that simply is not in the middle. As the rotation point is off-set then, as I've said, inevitably the model finishes to one side of where it went in - and it's quite correct that it should do so.

This is in complete contrast to a stall turn. In this the aircraft climbs vertically, must come to a stop, and at the exact point of the stop should rotate about its CoG - that is it should rotate about its centre which should remain fixed in space while the aircraft rotates around that point. It then should go down exactly the line it went up. (Ideally!) Without wagging its nose!

So, what's the difference when you are flying them? Its really all about timing - a bit like the secret of joke telling! If you put in the rudder whilst still moving upwards what you will get is a wingover. To get a true stall turn, and so down the line you went up, you must time the instant when the rudder goes over to just the point when the aircraft stops moving vertically. At this point there will be no movement induced airflow over the rudder (and hence no control) unless you keep the prop going. So one important "trick" is to enter the vertical climb at full throttle, then throttle back (not to zero) - to about half way or so, then wait for the aircraft to stop,....then straight away rudder over, the prop wash at half throttle will give you the rudder authority, as soon as the nose passes the horizontal rudder out and be prepared to put in just a dab of opposite to stop the nose swinging like a pendulum passed straight down - thus checking the "wagging nose" syndrome! Then just let it descend vertically - you may very well have to add a little down elevator as the speed builds to keep it truly vertical - the aircraft will naturally try to pull out as the speed increases and the wing makes more lift. At the same height as you achieved vertical going in start your pull out. Not too hard or a flick will result.

Hope this helps.

BEB

[Charles Smitheman]

I was most fortunate to have this manouever explained to me by an eminent test pilot. (right place right time) He had even made a model to demonstrate it, using protractors and bits and bobs. I hope that my description here is understandable.

A wing over is a constant rate turn performed on an inclined plane! Phew.

Here goes:

1. Pull the aircraft up into a constant rate climb. This can be any angle commensurate with the power to weight ratio of the aircraft in question. An Extra for example could do a vertical climb, but the turn could be performed by a Cub at a moderate climb angle.

2. Roll to the desired bank angle using ailerons only.

3. Center the ailerons.

4. Pull up elevator to turn the aircraft until it is facing in the opposite direction.

5. Using ailerons roll the aircraft back to wings level.

6. The aircraft should now be descending on the same plane that it ascended on, in the opposite direction, and the diameter of the turn away from the path on which it ascended.

7. At the entry altitude, the aircraft should be recovered to level flight using up elevator.

The important thing about the wing over is that there is no yawing of the aircraft with the rudder. This does suggest that one would have to cheat with a lazy bee!

If one wishes to return along the same path as that on which one ascended, it is necessary to cheat.

The purpose of the demonstration that I witnessed was for the safe displaying of aircraft at airshows. Apparently pilots have in the past come to grief due to not performing this manuever correctly.

I have tried following the above step by step guide with several of my models, and it works, and is very pleasing to the eye. Well, my eye anyway!

And I cannot spell manouver!

Charles

[Spikey]

Thank you very much, gentlemen. Yep, it's the cheating that's eluding me! I do actually appreciate that you shouldn't exit a wingover going back whence you came, b I was aiming for brevity and obviously hadn't had enough coffee to think of "exit on the reciprocal of the approach heading".)

So, given that I am currently aileronless (and in general happy to be so for the time being), I start my wingover by doing a very nice steep climbing turn. Then seeing as how it is indeed all down to the timing, what should my thumbs be doing when once I'm at 90° to the approach heading?

PS Ref stall turns, I loved doing those in a Chipmunk but they were nowhere near as much fun in the JP3

[Charles Smitheman]

Hi Spikey,

Essentially its: Climb, roll to a bank angle (you will have to use rudder) , maintain a constant bank angle whilst turning with elevator, opposite rudder to straighten the wings and head back down whence you came. Actually very easy. You will probably get some fishtailing due to being rudder -elev. With a lifting model you may need down elevator to make it follow the descent path.

The aerobatics enthusiasts practice with stick models, like kids playing, it looks hilarious but it really helps to get the idea.

Charles

[Dane Crosby]

Aw come on Spikey, I used to teach aeros on JP 3a and JP 5a. Stall turns are superb. anything from the basic stall turn to the vertical roll into a nodding reverse stall turn. The added bonus in the JPs was that the engine kept going whereas the Chippy (which I also instructed on) would often cut out when experiencing zero or negative "g". The most fun wing overs I did were in the venerable SK3 - at least until they installed HUMS

[Essjay]

Posted by Charles Smitheman on 20/01/2015 08:35:22:

I was most fortunate to have this manouever explained to me by an eminent test pilot. (right place right time) He had even made a model to demonstrate it, using protractors and bits and bobs. I hope that my description here is understandable.

A wing over is a constant rate turn performed on an inclined plane! Phew.

Here goes:

1. Pull the aircraft up into a constant rate climb. This can be any angle commensurate with the power to weight ratio of the aircraft in question. An Extra for example could do a vertical climb, but the turn could be performed by a Cub at a moderate climb angle.

2. Roll to the desired bank angle using ailerons only.

3. Center the ailerons.

4. Pull up elevator to turn the aircraft until it is facing in the opposite direction.

5. Using ailerons roll the aircraft back to wings level.

6. The aircraft should now be descending on the same plane that it ascended on, in the opposite direction, and the diameter of the turn away from the path on which it ascended.

7. At the entry altitude, the aircraft should be recovered to level flight using up elevator.

The important thing about the wing over is that there is no yawing of the aircraft with the rudder. This does suggest that one would have to cheat with a lazy bee!

If one wishes to return along the same path as that on which one ascended, it is necessary to cheat.

The purpose of the demonstration that I witnessed was for the safe displaying of aircraft at airshows. Apparently pilots have in the past come to grief due to not performing this manuever correctly.

I have tried following the above step by step guide with several of my models, and it works, and is very pleasing to the eye. Well, my eye anyway!

And I cannot spell manouver!

Charles

Charles, I have a feeling what you've described here is a "humpty bump", which is a totally different manoeuvre. Try Googling "humpty bump" for an explanation and explanatory diagrams.

Steve

[Charles Smitheman]

Steve,

You are correct a humpty bump would be the same if done from a VERTICAL climb. A wingover can be done from any angle climb between level flight and vertical. Depending on your whim and the power of the aircraft.

Charles

[Chris Bott - Moderator]

A wingover looks like the pic below, a humpty bump has a half loop to make the turnaround and usually has some sort of roll in the up lines and downlines, doesn't it?

Edited By Chris Bott - Moderator on 20/01/2015 11:50:54

[Charles Smitheman]

Nice picture Chris.

I actually hadn't thought about it before, but a humpty bump would be a special wing over just as a circle is a special ellipse!

In the picture the plane climbs to an angle, and rolls to an angle, rolls out again and dives again at the same angles. With a humpty bump the angles of climb and roll are ninety degrees. Thinking on the hoof, There is also the option with the humpty bump of rolling through 180 degrees, when it would I suppose no longer be a wing over! Ooh my brain is beginning to steam up now..

[Bob Cotsford]

I can't see Chris' picture for some reason, but I always understood a wingover to be primarily a job for elevator -rudder - elevator, possibly with opposing aileron to counter rudder induced roll. I.e., as per BEB a very loose stall turn performed without stalling.

[Chris Bott - Moderator]

Peter Jones shows the humpty bump on the improve your aerobatics thread, as this:

[Dave Hopkin]

So the wingover is a flat rudder controlled U Turn carried out on a slant?

and the Humpy bump is an sort of vertical immelman with a 90 turn before and after?

[Charles Smitheman]

Hello Bob,

I think that was precisely why the demo I saw was made,

if one were to get the controls crossed, turning at low altitude, at an airshow, it would be too easy to enter a spin. The whole move(easier word!) is done with the slip ball in the center.

Of course someone else in the modelling fraternity may have a quite different interpretation, I do not know.

It is not a move that if have seen done often with models, although it is easy and fun, and looks nice.

Charles

[Spikey]

Posted by Dane Crosby on 20/01/2015 10:10:18:

Aw come on Spikey, I used to teach aeros on JP 3a and JP 5a. Stall turns are superb

Superb but boring IMO. But I always did prefer a fan on the front to a blowlamp on the back.

[Tim Cheal]

Its ironic how our experiences change our perception.

As a JP QFI many years ago I would have written that there was always the excitement of the engine surging on the JP! (I had an engine surge in a JP5 once during a reverse stall turn.) I have very little chippy experience, but never had the engine stop!

The experience analogy probably applies to a wingover. They are a great way of turning an aircraft around (especially a non aerobatic one), but I suspect we all have a different experience and understanding of what a wingover actually is.

Personally, the less defined it is the better, as there are less guidelines to measure it against and I am more likely to get it right!

Tim

[Spikey]

Posted by Tim Cheal on 20/01/2015 18:30:27:

Personally, the less defined it is the better, as there are less guidelines to measure it against and I am more likely to get it right!

Tim

Nice one Tim

[Ross Clarkson]

There was a brilliant article written in RCME about how to do Wingover's and Stall Turn's. I will try and find it but sitting down and reading it a few times really made the differences click in my head and improve my manoeuvres immensely.