Aerobatics Training

[garlicbreadhamburger]

I take it that Canada's aerobatic training is in a pretty sad state if the main discussions revolves around "Will you die learning from YouTube"

[NobodyImportant]

As much as I disagree with digits, perhaps I can offer a counterpoint.

I've recently been flying wingovers. Is that an aerobatic maneuver? If I just kick over the rudder in a stall (in a light single piston), that's spin practice. If I do it a bit more gently, now it's a wingover. If I don't kick the rudder at all, it's just a stall. If I do that at full power, there is very little difference between a power-on stall and an incipient spin, and a wingover is somewhere in the middle.

At a level enough attitude, it's just a turn. At an aggressive (say, 45°) attitude, it's a wingover. At a 90° attitude, it's a hammerhead - and perhaps a tailslide. So when exactly does it turn into aerobatics?

The point being, I feel confident flying wingovers, and I don't feel confident flying hammerheads. It's a very fuzzy line between them. So when am I flying "aerobatics", and when am I flying "edge of stall practice"?

[PilotDAR]

So when am I flying "aerobatics", and when am I flying "edge of stall practice"?

From CAR 101.01 Interpretation:

aerobatic manoeuvre means a manoeuvre where a change in the attitude of an aircraft results in a bank angle greater than 60 degrees, an abnormal attitude or an abnormal acceleration not incidental to normal flying; 

The bank angle is quantitative, and not at all fuzzy. The latter two criteria more refer to the position an airplane may be placed in, from which departure from controlled flight, or exceeding a limitation is a risk, so more difficult to quanitfy.

Like many things in flying, the hazard may not be at that moment, but more the situation a pilot has placed themsleves in, from which extra pilot skill will be required to recover, particularly if loose an engine part way in.

I have always been a strong advocate of spin and unusual or aerobatic training for pilots. It's fun, and makes any pilot better and more confident. I also advocate doing that flying in a suitable type, and with some qualified instruction.

[photofly]

The weakness of that definition is that, in for example, spin training, bank angles regularly exceed 60 degrees and he attitude is quite abnormal but “aerobatics” are not being conducted.

The FAA went so far as to write a legal opinion that says that since spin training is “normal” flying it doesn’t count as aerobatics in the US, doesn’t require parachutes to be worn, etc:
https://www.faa.gov/about/office_org/he ... tation.pdf

[PilotDAR]

for example, spin training, bank angles regularly exceed 60 degrees and he attitude is quite abnormal but “aerobatics” are not being conducted.

Yes, however, presuming that that training is being done in a spin approved airplane, it's being done within the approved limitations, so you have an approval to do it in that type.

If you have a valid reason to fly spins in a type which does not have approval to be spun, you seek approval for spinning (and/or exceeding Vne) by flight permit, which I have done many times. The flight permit becomes your approval, in the absence of any other, to fly an "aerobatic" maneuver.

[2R]

https://www.kansascity.com/news/nation- ... 33518.html

Make sure you are fit before you start Aerobatics . Start with gentle jogging to strengthen the internal core . You must be fit or you may black out and if you are solo , you might hurt someone else on the ground .

A G meter and parachute should also be used .

We went to look at a cream puff airplane . It was not as advertised . It was never a trainer the seller said , how did it get wrinkles top and bottom if it was never a trainer ask me ? Seems a family member was teaching himself aerobatics . I advised my friend against buying the aircraft without a estimate to repair the wrinkles . Owner got upset and asked us to leave . The cost to repair would have been more than half the asking price and he was not willing to fix it before sale .

The big danger is that the damage done in uncertified aerobatic aircraft may not be apparent immediately, hence the G meter requirement for aerobatic aircraft , helps the mechanics find problems before they kill .

[digits_]

The big danger is that the damage done in uncertified aerobatic aircraft may not be apparent immediately

How would there be a difference between certified and uncertified aerobatic aircraft regarding showing damage?
The most performant aerobatic aircraft are not certified, but homebuilts/experimental designs.

You probably mean aircraft in which aerobatics are prohibited, but even then the question stands: why would there be a difference in how apparent damage would be?

[photofly]

An aircraft certified for aerobatics will have a g-meter, and be built to withstand higher loads. Damage is less likely because the airframe is sronger, and the g-meter can demonstrate overstress.

[digits_]

An aircraft certified for aerobatics will have a g-meter, and be built to withstand higher loads. Damage is less likely because the airframe is sronger, and the g-meter can demonstrate overstress.

Agreed, but that was not the statement made.

I don't think there is a difference in how damage will display itself in aerobatic vs non aerobatic aircraft. If the aircraft in 2R's example would have been an aerobatic aircraft that got overstressed, I figure you'd have seen damage in the same location. It would have taken more G to get to the same level of damage, but it would show up as well.

A G meter could demonstrate overstress, but it doesn't make damage more visible, merely that there is a potential for damage. It could trigger a more in depth inspection, but the damage itself won'be more or less apparent.

[Beefitarian]

Gosh digits_ you’re worse than Hitler. How many have died because of you saying you learned aerobatics on your own?

Gives me the shivers.

[digits_]

Gosh digits_ you’re worse than Hitler. How many have died because of you saying you learned aerobatics on your own?

Gives me the shivers.

The way this topic is going, I actually thought you were serious for a full 5 seconds!

[PilotDAR]

I won't speak to characteristics of non certified airplanes, that's between the the designer, builder and pilot. Some are well known to be excellent, a few I've looked at I would not fly at all, let alone pull G in.

For certified aerobatic planes, the approved maneuvers will be listed in the flight manual, and a description of how to enter them. Could it be more clear?

That aerobatic plane will not only have been found to be compliant with all the required loads, but also the combination of loads. And, beyond that, it will have met the requirement for not requiring unusual pilot skill and attention for those maneuvers. So, if the pilot is somewhat imprecise about the entry, there's a little room to botch it, and still complete it without exceeding any limitations. An non aerobatic type has not been required to demonstrate that extra margin. For example, all single engine certified planes are required to demonstrate recovery from a spin, but few are spin certified. The difference being that the non spin certified airplanes will recover from a spin, but may require skilled, precise piloting - no margin to get it wrong.

The damage which may be done to the airframe may be by a combination of loads, acting on a part of the airframe not normally thought to suffer - you can break structure inside, without a wrinkle being visible on the outside.

Example: C 150 horizontal stabilizers are mounted on the upper surface of the tailboom, and are held in place by four bolts. On earlier 150s, the portion of the tailboom through which the forward bolts pass outward into the H stab was subject to cracking. This cracking is difficult to see without removing the H stab. The forces producing the cracking could be careless/abusive flying, or simply very poor ground handling - pressing in the wrong place on the H stab to push the plane around.

Cessna improved a doubler in this location in the Aerobat version of the 150. It was such a good and simple improvement, that all later 150's and 152's have that improved doubler. What you do in an Aerobat or later model 150 maybe tolerable for the airframe, but doing the same thing in an earlier 150 could crack the tailboom locally, and be difficult to see without removing the H stab. Cessna SID 55-11-01 for those who are interested.

So, for certified planes, it's just better to fly them within their limitations, and intended maneuvers.... (and don't ground handle Cessnas by the H stab!)

[2R]

https://aviation-safety.net/wikibase/40417

The scuttle I heard was they would do these amazing Partenavia P68c demo sales flight and use a different new aircraft at each new event . For some reason this aircraft was used again by the same pilot that overstressed it at a previous air show sales . No g meter so the “ pilot did not realize the damage he had done by stunting . In a way it was Karma that he found out the hard way .
A lot of damage done by turbulence and aerobatics can only be seen with xRays and ultra sound inspections .Even the keenest eagle eyed pilot will not see the damage , But an honest NDT inspection can detect the fatigue stress cracks .

That pilot single handed destroyed the market for a very good aircraft with his stunting .

It is always interesting to read accident reports on aircraft you have flown and listen to other pilots who said how they used to operate those aircraft . One Van that crashed on Vancouver Island was rumoured to have flown over torqued on a regular basis rather than turn around when the icing got too much they would firewall it . Yup the cause of death was engine failure , but what could have been done to the accident before the engine showed the fatigue that is not normally found in a regular overhaul . They just added five grand to everyone’s overhauls because they did not follow the POH . Failure to follow the POH is a very common error in accidents .
Follow the rules , especially those rules that were written in blood .

[Beefitarian]

Fun joke.

The way this topic is going, I actually thought you were serious for a full 5 seconds!

Awesome! I almost ruined it by sending you a PM. Then I switched and decided to wait for your reaction.