Talk:Aerobatic maneuver

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I thought I would put down some of my ideas for this page. If you disagree then lets chat about it and hopefully we can improve this section of the Wiki. Daleh 12:03, 24 August 2005 (UTC)

Aditivos ando To-Do l--190.28.134.16 (talk) 05:21, 15 July 2013 (UTC)ist

• Alphabetacise the list of figures, or at least put them in some order. -- DONE 9-28-05
• Give each figure a brief description, but have a link to a page with further details.
  • Further details can be the how and why: Explanation of flight dynamics, gyroscopic moments, etc.
• Possibly add either the Aresti symbols or some sort of diagram
• Links to the Aresti Catalogue
• Refrences

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Made changes to the "Hammerhead" paragraph - Previous text was technically incorrect and misleading in description. Wrote article about Lomcevaks.

InvertedSpin 03:37, 6 November 2005 (UTC)

Even though it tries to explain the terms, it uses terms that are not accessible enough. I was totally lost by the explanation of a cuban eight, and even the first term uses "maximum climb" as though it was perfectly obvious what that was. Keep it accessible, use words like "up" and "down" and "really fast" if you have to :) Stevage 09:50, 12 May 2006 (UTC)

Major change

I have begun tabulating the figures from the bulleted lists. The list was looking untidy, and the only neat way to add images was to use a table. The main headings are alphabetacised, while the sub figures (eg the Cubans) are in a mostly logical order. I am using cropped Olan gifs. See the actual Images page to look at the credits and also the naming scheme. The figures should be vectorised but I do not have the correct software. It would be nice to add a "ribbon" style diagram that would be truer to the shape of the figures as well as the Aresti symbols. (i.e. a fourth column.) Anyone good at that kind of art? If anyone has any objections to these changes please let me know. Daleh 21:39, 13 May 2006 (UTC)

Request from Ramstein airshow disaster

Could someone that is skilled in the Aresti notation please help to produce an illustration of the maneuver that lead to the Ramstein airshow disaster. We currently have one fair use image of the maneuver: Image:Cardioid.jpg, but it will have to be replaced as it does not fulfill WP:FUC. --rxnd ( t | € | c ) 21:50, 1 August 2007 (UTC)

Wing-over/Chandelle needs a graphic

Some sort of graphic illustrating the wing-over maneuver would greatly contribute to the meaning of that term. Even a link to a reliable video would be helpful. The description really doesn't fully explain it to a reader. --Khatores (talk) 21:34, 30 November 2008 (UTC)

• History: The Smithsonian Institution and Museum in Washington DC, shows a list of the first people in looping the loop around the World. Number six in the World, first in Spain in doing this aerobatic manoeuvre was Manuel Zubiaga-Aldecoa, with a Bristol airplane of his property. It seems that the achievement was unintended, and took place when the pilot fully opened the throttle of his airplane engine, the machine circling the figure by its own. Someone said that if the Wright brothers first airplane had had a more powerful engine, it would have looped the loop too. —Preceding unsigned comment added by Jgrosay (talk • contribs) 11:55, 13 February 2010 (UTC)

Needs more basic information.

I have added a section that actually (attempts to) explain what the terms "loop", "roll", "spin", and "hammerhead" mean, as it doesn't say anywhere on the page what those actually are, only that maneuvers are made out of these component parts. It just so happens that I got to this page because I was trying to find out what a Hammerhead turn was. It didn't help at all. (Incidentally, there is a page on the Stall turn, but it is so technical it was not entirely clear even to me who knows a little about aviation. There is also a page explaining what a Spin (flight) is, but no link to that page here. "Loop" and "Roll" just bring you back to the page on Aerobatic maneuver. Big help. I remember a time when I wasn't clear on what a spin was, or which one was a loop and which was a roll. I recall coming here to this page and not learning much. A lot of people coming to this page are likely in the same position. It is annoying. Thus, I have taken it upon myself to add a section attempting to explain in simple terms what these elementary maneuvers are, and supplying links to the few pages out there that pertain to the subject, if anyone wished to read further on the matter. There is no page for "roll" and "loop", so what people read here is all they are going to get. It's not great, but it's the best I could manage, and it was hard to keep it as short as I did. If anyone wishes to improve it or correct any of the details I added, feel free, but please don't just delete it, because there ARE people out there who don't know this stuff and would like to learn. If there isn't any other page explaining what a "loop" is, it ought to be said here, or at least there ought to be a link to a place that does say what it is. I bet the Simple English wiki has a good basic explanation....45Colt 18:20, 15 February 2014 (UTC) — Preceding unsigned comment added by .45Colt (talk • contribs)

Stall turn

When I was a passenger for aerobatics in air cadets, every time they did a stall turn the engine stopped on the way up and restarted on the way down. Could this be why it's called a stall turn? Yevad (talk) 13:01, 28 August 2015 (UTC)

No. It is usually a very bad idea to shut the engine down in mid-flight. (What if it doesn't start back up?) Older, post WWII, planes did not even have starters; you actually needed to climb out of the plane and spin the prop by hand to start them, which is extremely difficult to do in the air. What you most likely heard was the pilot cutting off the throttle, causing the engine to slow down but not to stop, and the reapplication of throttle after the maneuver was done.

...but the prop always stopped and everything went very quiet. The aircraft was a DeHavilland Chipmunk. I don't remember if they cut the throttle or not but I do remember the engine restarting when you were facing downwards, I always presumed that the airflow turned the prop and gave a similar effect to bump starting a car. Yevad (talk) 19:35, 9 May 2016 (UTC)

It's possible to start a jet engine by diving; especially if it's a turbofan. (See Windmill start.) I've never heard it done with a turboprop, though. The problem with props is that they're designed more like a wing than a fan (props pull, fans push), so there is not as much radial force from oncoming wind. The problem with reciprocating engines is that darn compression stroke, and I've never heard of the radial force of a stationary prop in the wind being able to overcome it, certainly not enough to start the plane without a starter. To push-start a car it needs a clutch, so you can get it up to speed before popping the clutch, generating enough force to turn over the engine. Planes don't have clutches.Zaereth (talk) 07:02, 10 May 2016 (UTC)

Stalling in an aircraft does not refer to the engine, but to aerodynamic stalls. This happens when the plane loses lift and begins falling instead of flying. Zaereth (talk) 16:52, 28 August 2015 (UTC)

I know the difference between an engine stall and aerodynamic stall :p Yevad (talk) 19:35, 9 May 2016 (UTC)

However, I might add that there is such a thing as a propeller stall (prop plane) and a compressor stall (jet plane). However, both of these are also variations of aerodynamic stalls. A prop can stall if the tips of the propeller begin to break the speed of sound. The same can happen to the vanes of an axial compressor, especially at high-altitude, high-g turns. This causes the jet to go Phhht ... Phhht ... Phhht ..., instead of a smooth stream and can lead to engine shut-downs. It was a big problem on the older F100 engines until the introduction of variable vanes. Zaereth (talk) 18:32, 28 August 2015 (UTC)

Thanks :) Yevad (talk) 19:35, 9 May 2016 (UTC)

No, you would not shut down the engine while doing a stall turn in a Chipmunk. The Chipmunk can be a little tricky to stall turn because of the effect of the propeller slipstream (the vortex of air created by the propeller) at low speeds and high throttle. The Chipmunk is much easier to stall turn to the right than it is to the left.

The procedure for a stall turn in a Chipmunk is as follows. First, go full throttle and dive to achieve and entry speed of at least 120 knots. Keep the throttle full, and pull up to a vertical attitude and zero bank. You'll need to keep slight forward-stick pressure to maintain attitude. In a vertical climb, bank is controlled with rudder. When the speed begins to run out, progressively apply rudder to swing the nose over. As the aircraft yaws, it will start to roll, so slight aileron will need to be applied, countering the roll, to keep the yaw a nice, even, banking turn.

For a right turn, when the nose is even with the horizon cut the throttle, to give a smooth transition as it drops through the horizon to vertical. Opposite rudder should be applied to reduce nose oscillations when nose-down vertical is reached.

For a left turn, slowly begin cutting the throttle as soon as the turn starts (in the nose-up, vertical position), timing it so the throttle is fully closed when the plane has yawed to a horizontal position (nose even with the horizon). If this is not done, the propeller slipstream will prevent the stall-turn to the left. At no time during any of this should you shut down the engine.

To exit, dive to regain speed, then pull up to a horizontal attitude. Check oil pressure, and reapply throttle when oil pressure returns to normal. Hope that helps. Zaereth (talk) 02:32, 10 May 2016 (UTC)

I talked to a friend of mine who used to fly Chipmunks. He says that fuel starvation of the engine is a common problem during aerobatic maneuvers in this particular plane, causing the symptoms just as you described. Zaereth (talk) 00:18, 12 May 2016 (UTC)

Thanks for the insight. I'm wondering how the pilots used to restart the engine. Excuse my ignorance, the planes were always up and running when we got in, but do they have an electric starter motor? Yevad (talk) 12:23, 26 May 2016 (UTC)

What would typically happen is that the engine would loose fuel in an excessively negative G maneuver, causing it to hesitate (hiccup) but usually not to fully stop. In a high-speed maneuver, even if the engine dies, the prop may keep rotating due to the windmill effect and because the prop never lost rotational speed. In a low speed maneuver, especially one below stall speed, the prop may stop completely. Then you're in trouble, because you'd have to dive well beyond VNE (Velocity never to exceed) in the hopes of generating enough force to overcome the compression stroke of the engine. Fortunately, your Chipmunk was probably equipped with an electric starter, a Coffman starter, or both. By your description, I'm thinking it was more of a hiccup situation, as a full engine-stop would be highly unusual and cause for great concern.

I hope that helps. Unfortunately, this conversation has nothing to do with improving the article, so that will be all I'm going to give. There are many forums out there better suited to this type of conversation. Zaereth (talk) 19:40, 26 May 2016 (UTC)

Thanks for the help folks. Sorry to detract from the primary subject of this page.Yevad (talk) 22:49, 13 June 2017 (UTC)

Looking for 'Bent Loop'.

According to the BBC a crash at a UK airshow happened while a pilot was "performing a manoeuvre [ ] known as a bent loop..." https://www.bbc.co.uk/news/uk-england-sussex-46882177 So I came to wikipedia hoping to discover exactly how such a manoeuvre differs from other types of loop. Does anyone here know what it means? Is bent loop an actual technical term? Is it a British name for a thing also known by another name? So far searching here reveals no relevant results.86.155.27.134 (talk) 18:44, 16 January 2019 (UTC)

That's one of those things that's almost too subtle to be called an individual maneuver of its own. I've never heard it called anything before today (except maybe a screwed-up loop), so it may be a British thing, or even a name given by the pilot himself. This is basically something between a loop and a barrel roll, but closer to a loop. (Much less roll than a barrel roll attack.) Basically, you perform a loop like normal, but when nearly inverted (45 to 60 degrees above the horizon) you start to roll the plane slowly as you loop. You can imagine the path flown to look something like a hula-hoop that has been cut open, and the two cut-ends are pulled slightly apart (laterally) so that the circle is no longer in alignment but shaped more like a spring (the loop is bent). Actually, "screwed loop" wouldn't be bad either, as you can also picture it like threads on a screw rather than a perfect circle. Not to mention it's easy to screw-up a loop that way by accidentally applying aileron. Zaereth (talk) 20:44, 16 January 2019 (UTC)

Thank you for your explanation, that's interesting & informative for me. I suppose there will be so many variations on standard manoeuvres that it would be impractical to include everything in an article like this, so I'll leave it to specialists to decide whether it needs a mention here. I have now though found a page currently entitled '2015 Shoreham Airshow crash' which at some point might benefit from an explanation if a suitable citation could be found.86.155.27.134 (talk) 23:09, 16 January 2019 (UTC)

You're welcome. Both there and here, lack of suitable citations are indeed the problem. Zaereth (talk) 23:15, 16 January 2019 (UTC)

The manuever was probably intended to be a quarter cloverleaf.

Source for relation to 2015 Shoreham Airshow crash- https://www.pilotweb.aero/safety/shoreham-airshow-disaster-hearing-set-for-november-1-4708105

I've spoken to a British aerobatic pilot, and he's never heard of a "bent loop" - possibly this is a term invented by a journalist. (Hohum ^@) 21:16, 17 January 2019 (UTC)

Correction, the "bent loop" term was coined in the AAIB report on the crash. Essentially, a bent loop being like a quarter cloverleaf, except instead of being a 90 degree difference between entry and exit direction, it's whatever direction change is required. (Hohum ^@) 21:26, 17 January 2019 (UTC)