Upset training

[mcrit]

Even if you zero the G it is better... and minus 1 to 1.5 G may be absolutely paramount.
You have to stop all pitching of the nose towards the ground, apply full aileron and roll the aeroplane level.

You can do it that way, but most people find being pushed up out of their seat while various bits of FOD rise up off the floor to greet them to be very distracting. If your rate of role is fast enough you will find yourself back upright very quickly, and thus the + g will be bringing you out of the dive. If you are flying the 152/172 you can get away with putting the fuel and oil system into 0g for a while. Not all a/c are like this. I can think of 2 off the top of my head that have restrictions when it comes to 0g flight.
When I said to maintain slight +g I meant slight. About +0.5, while rolling out. That is not going to drag your nose all that low all that quickly, especially if you get the roll going.

[GoinNowhereFast]

Are you one of the 10 highly skilled and experienced aerobatic
pilots in Canada? Statistically, it is doubtful. I can count
these people on the fingers of both hands.

You've got 10 fingers? I've only got 8 fingers and 2 thumbs.

[Shiny Side Up]

The origin of the original question was the ignorance of too many instructors questioned on it and giving unsatisfactory answers.

Unfortunately many instructors forget the cardinal rule of instructing: Don't bullshit the students. If you don't know something, admit it to them. Ammend that with that you'll find out for them. They are only human though - and pilots, for whom bullshit comes as naturally as it does fishermen - there are limits to what is excuseable though. The real unfortunate part is when someone truly believes the bullshit they dish out, or that has been passed down to them.

Like taxying and running up with the control column forward, the art of flying/operating an aeroplane well and with consideration has largely died.

The first bit I have to ask about MichaelP, aside from when you'd have a strong tailwind, why would you taxi with control column forward? Maybe I'm misreading something?

I hear you about the consideration though. Courtesy often gives way to the rush that people are always in.

[Strega]

..

[MichaelP]

The first bit I have to ask about MichaelP, aside from when you'd have a strong tailwind, why would you taxi with control column forward? Maybe I'm misreading something?

I wouldn't!

But you have to see the Cessna drivers here who are taught this way with the 172's turning to do their runups with the nose leg bottomed the nosewheel tyre rolling to the side of the wheel and the propeller getting precariously close to the ground while picking up FOD.

I point it out to students all the time.

The problem I have with all of this is that these students become pilots with bad habits already fixed in their subconcious.
I contend that a lot of tailwheel accidents are because the pilots were not taught good habits in the nosedraggers in the first place.
What a nosewheel forgives a tailwheel won't.

When I said to maintain slight +g I meant slight. About +0.5, while rolling out.

This is not easy to do.
You must kill all pitch towards the ground and roll the aeroplane as quickly as possible.
I would not be concerned about the engine when it comes to something like this. Close the throttle and roll back to level. I know of no engine that has not run properly if the throttle was closed in negative G.
I believe many engines will come apart through overspeeding in a dive and even +0.5 G inverted will put you through Vne very quickly with a good chance the engine will overspeed.

Fortunately for most of us we will never see this happen, and likewise we will never see a forced landing, but we should be prepared for such things.

[Shiny Side Up]

I wouldn't!

Ah, my mistake then, I thought you were advocating it for a minute.

[Blue Side Down]

If a pilot is a keener and is willing and able to spend the money required to become proficient at basic aerobatics, good for them, the skills and insight they gain will compliment their 'normal' flying experience nicely. Implementing a requirement for upset training into the licensing requirements, however, would be a step in the wrong direction. I'd actually expect it to be more of a hazard than a help- just think of all the exciting accident reports which would follow when every fresh off the block Cessna driver believes they've got the skills to Bob Hoover their beast out of a triple-7's wake on short final.

Of the three scenarios proposed where upset training would be an 'asset', all require a grave mistake in judgment to be made before the opportunity for a heroic recovery arises. In the case of the wake turbulence, if you need to ponder whether or not you should put any negative g on an airframe rated for -1.7 or whatever, or zero-g the beast, ballistic roll upright and figure out what to do with the blazing speed once you're right side up again, I hate to break it to you, but you've got bigger problems coming- in fact, a whole world of a problem. Similar with the disorientation in cloud- by the time you realize you're in trouble, the only thing left to do will be to check the airspeed indicator out of curiosity to see where it actually pegs before the wings start bending the wrong way. The only thing that would save pilot in an 'in cloud' situation would be a thorough and disciplined method of flying on the gauges to keep the airplane from getting away in the first place. Students would be better off learning about risk identification and mitigation than fooling themselves into thinking just because Bob Hoover flew upsidedown in a twin, they can too. There were a couple other guys that flew twins at airshows because they thought they could put on a spectacular show within the g limits of the airframes- one guy was in a Baron and the other in a Partanavia iirc- they put on great shows right up to the last one when the wings came off. And note that these guys were flying within the certified g-limits of the airframe- what they did was discover the fatigue limits of the spar.

Here's my thought- discover and enjoy aerobatics for what they are, but lets not naively try to convince ourselves that five hours looping and rolling around the sky will do any good fifteen hundred IFR hours down the road. Stay vigilant, stay out of trouble, don't run out of altitude inverted.

[Osiris]

I disagree.

In simulator studies, pilots (experienced pilots) who had no aerobatic training and no upset training ALWAYS pulled through (and crashed) to recover from "surprise, you're inverted" whereas those who had some aerobatic experience rolled out and survived the scenario. (sorry I don't have a link)

To say that a student is better off learning about risk identification and never actually seeing the inverted attitude is like saying that stall/spin prevention training is better than actually going out, spinning a plane and recovering. Nothing beats going through the motions.

Rolling a twin or a jet out of the inverted should be a very survivable thing if done properly. And the only way to do it properly is to train for it. The captain of the FedEx DC-10 that experienced that attempted hi-jacking rolled his aircraft all over the sky. When they got it on the ground, the plane was well over-stressed, but they were still able to fly it to the ground. Granted the DC-10's got an incredibly strong airframe, but the Baron and Partanavia are equally capable of surviving a single occurrence of upset recovery. Those air show crashes were the result of cumulative fatigue, which has the potential to produce significantly greater wear on an airframe than experiencing a single loading event well beyond the limits of the aircraft. Heck, a Hawker 800 recently took 4 snap rolls and remarkably stayed in one piece: http://www.pprune.org/biz-jets-ag-flyin ... times.html.

I think it's safe to say you'd stand a reasonable (or at least better) chance of surviving upset in any aircraft provided (just like a stall or spin) you had sufficient height to recover and you knew how to recover. And if you haven't gone up and done it, you don't know how to recover! Five hours of loops/rolls is a great benefit to any pilot. Some form of re currency every once in a while would make it even more valuable.

[iflyforpie]

+1

Unless you've been inverted in an aircraft you have no idea what it is like. It is totally unnatural to push forward while hanging in your harness and trying to keep your feet on the floor to reach the pedals. You will need to do this if your nose is anywhere near the horizon when you are inverted in a light aircraft.

Mcrit, I don't know of any aircraft other than perhaps a powered parachute that has an all-out restriction against negative-G flight. All normal category aircraft are stressed for -1.52 G. You will loose some oil and battery acid and your engine might sputter, but you will save the aircraft for the worst case scenario of a forced landing if the engine doesn't pick up right away. I'd rather be upright with an engine failure than upside down with everything running.

[AuxBatOn]

Mcrit, I don't know of any aircraft other than perhaps a powered parachute that has an all-out restriction against negative-G flight. All normal category aircraft are stressed for -1.52 G. You will loose some oil and battery acid and your engine might sputter, but you will save the aircraft for the worst case scenario of a forced landing if the engine doesn't pick up right away. I'd rather be upright with an engine failure than upside down with everything running.

Lots of turbines/jets have a very limited time at or around 0G.

[iflyforpie]

I find that surprising considering that some of the most mundane jets are used for weightless training for relatively long periods of time.

[mcrit]

Lots of turbines/jets have a very limited time at or around 0G.

Once early in my training in the sim I stuck around the 0g mark for a bit to long and was rewarded with a chip light, engine failure, forced landing and major earfull in that order.
The way it was explained to me was that exeeding the time at 0g caused my oil pump to cavitate because the system couldn't scavage the sump correctly. This pooched the oil pressure and the rest followed, does that sound about right to you AuxBat? The fellow also mentioned that it was possible for the fuel system to loose pressure for a similar reason, with unpleasant results.
If you find yourself inverted and decide to apply lots (and it will take lots) of forward pressure to arrest the rate at which your nose is dropping, that is fine. Unless you fly upside down on a regular basis be prepared to be disoriented. Also be prepared to have to reverse your forward pressure to back pressure fairly rapidly once you are past the half way point of the roll.
If you choose instead to keep slight +g on during the whole thing, and use a rapid rate of roll (full aileron and lots of rudder), you won't be quite as disoriented and once you are past the half way point you will be pulling the nose up without having to reverse for control pressures. The whole thing is like a bastardized barrel roll.

[AuxBatOn]

Once early in my training in the sim I stuck around the 0g mark for a bit to long and was rewarded with a chip light, engine failure, forced landing and major earfull in that order.
The way it was explained to me was that exeeding the time at 0g caused my oil pump to cavitate because the system couldn't scavage the sump correctly. This pooched the oil pressure and the rest followed, does that sound about right to you AuxBat? The fellow also mentioned that it was possible for the fuel system to loose pressure for a similar reason, with unpleasant results.
If you find yourself inverted and decide to apply lots (and it will take lots) of forward pressure to arrest the rate at which your nose is dropping, that is fine. Unless you fly upside down on a regular basis be prepared to be disoriented. Also be prepared to have to reverse your forward pressure to back pressure fairly rapidly once you are past the half way point of the roll.
If you choose instead to keep slight +g on during the whole thing, and use a rapid rate of roll (full aileron and lots of rudder), you won't be quite as disoriented and once you are past the half way point you will be pulling the nose up without having to reverse for control pressures. The whole thing is like a bastardized barrel roll.

It was indeed what I was referring to. Oil problems and sometimes, fuel problems (but at that point, it's secondary, the oil problem is a far bigger problem, since it will do permanant damage.)


The other problem is that most people would not pull quite -1G, bringing them close to the 0G regime. Even thought it's dead easy to do, there is a tentendy to not push enough, since it can be unconfortable and akward.

[Hedley]

If you ever find yourself accidentally upside down (and
I hope you never do) ...

As mentioned above, push HARD forward while inverted
to keep the nose up (flat bottom wing) and rolling through
knife edge, FULL top rudder. Both of the above will result
in minimum loss of altitude, which may make the difference
between you and your pax living or dying that day.

IMHO better to possibly damage the engine than crash
and kill everyone aboard.

I personally would rather get the airplane back on the
ground with everyone safe with the engine possibly
damaged, rather than try to keep the airplane perfect
up until the moment that it was completely destroyed
in a crash.

[AuxBatOn]

I personally would rather get the airplane back on the
ground with everyone safe with the engine possibly
damaged, rather than try to keep the airplane perfect
up until the moment that it was completely destroyed
in a crash.

Agreed, but with a ceised engine, you're not in a much better position IMHO, which would most likely be the outcome of extended 0G flight in some turboprops/jets.

[Hedley]

I would rather be upright, with flamed-out engines,
which I have a chance of surviving, instead of crashing
inverted at high speed into the ground, which has
absolutely no chance of survival.

My father did a dead-stick instrument approach and
landing through a thick overcast in an F-86 in Europe,
back in the 1950's, even though Transport Canada
hates him because he is related to me. I guess they
are much hotter sticks than he is.

Bob Hoover did many successful dead-stick landings
as a North American test pilot, even though the FAA
hated him. Read his autobiography about why he
wasn't the test pilot on the XS-1 when it broke the
sound barrier.

There is a video on the net of an F-16 doing a dead
stick instrument approach and landing.

A friend of mine (TACA pilot) landed a B737 in New
Orleans with both engines flamed out due to rain/hail
and no one was hurt. The airplane was so undamaged,
Boeing put new engines on it and flew it out!

And of course, there is the Air Canada Gimli Glider,
and the Air Transat Azores glider.

Engines out is not a death sentence. Crashing
inverted at high speed is.

[mcrit]

I would rather be upright, with flamed-out engines,

If you get the roll and rudder in quickly enough you can be both upright and have happy engines.

[iflyforpie]

The KC-135 was regularly used for weightless training for astronauts. You can buy weightless adventures in Russia flying in an IL-76 where, according to their diagrams, you are at zero G for roughly 45 seconds. AFAIK these aircraft use non-inverted dry sump oil systems.

It also perplexes me because all of my inverted training was done in a Citabria 7GCBC, which has a wet sump oil system which definitely looses oil pressure when inverted. Inverted flight is restricted to 30 seconds and there is no restriction on zero G flight.

Just remember too that just because a chip light goes on, doesn't mean the engine is going to fail right away or even at all (sometimes accumulated 'fuzz' can cause one to go).

[AuxBatOn]

Just remember too that just because a chip light goes on, doesn't mean the engine is going to fail right away or even at all (sometimes accumulated 'fuzz' can cause one to go).

Well, a chip light means there is a significant amount of metal chips in the oil, meaning that the gear box is likely eating itself up. I had 1 chip light experience and it wasn't fun at all, torque going up and down, partial power, etc.

On a jet, it's the same kind of concerns, except you do not have the chip light warning.

0G in the Hawk was 10 seconds (-0.5 to +0.5 IIRC), I believe it was 5 on the Harvard II (-0.25 to +0.25) IIRC. I may have mixed the two, since it has been a while.

On the Hornet, 0G is actually a prohibited manoever, except for transient. -G is limited to 10 seconds

Even with an inverted oil system, it doesn't do any good in 0G.

[Rockie]

I don't know about cessna's and such, but anybody recovering from an upset in a transport category jet should leave their feet firmly glued to the floor and off the rudder pedals. Vertical stabilizers are not built to withstand rapid, full rudder applications and will probably depart the fix if you try it. And unless a light airplane is specifically certified for aerobatics I would be reluctant to try it in one of those at high speed too for the same reason.

[Hedley]

Good point - the certification standards for vertical fins
and rudders in transport category aircraft are disappointingly low.

The Airbus has a serious problem with this - airbus aircraft have
a notorious record for losing their rudders and/or vertical fins in
straight and level flight.

[Rockie]

I couldn't say if Boeing builds tougher airplanes than Airbus or not, and I have a lot of experience on both (even though I have gleefully participated in the ribbing as much as anyone). I do know that both are subject to the same certification standards, and Boeing has issued the same warnings as Airbus regarding rudder use.

[Hedley]

You must admit that Airbus's shed vertical fins and rudders
far more frequently than Boeings ... I googled this:

“Airbus products are the flimsiest and most poorly designed as far as airframe structure is concerned by an almost obsession to utilize composite materials.” In regards to the vertical stabilizer he said, “The vertical fin along with the composite hinges on rudder and elevators is the worst example of structural use of composites I have ever seen and I am not surprised by the current pictures of rescue crews recovering the complete vertical fin and rudder assembly at some distance from the crash site.”

[Rockie]

Everybody has an opinion as you know, and who knows where that one came from. It could be just a matter of dumb luck that it's only been Airbus products that have been caught in the situations resulting in vertical stab failure. The A300 in New York is the only confirmed one I know, and although it likely happened with AF447 it hasn't been confirmed yet. I don't know the difference, if any, between the two manufacturers in how they design the stabilizer connections to the fuselage, so I can't say if one is better than the other. Boeing could be just as weak but hasn't had the misfortune of suffering a failure from it yet. I don't know.

[iflyforpie]

Boeings tend to be over engineered. Even in the Aloha incident, the aircraft in question had nearly twice the airframe cycles the fuselage was designed for and still made it to earth in one (slightly smaller) piece. Can't say too much about Airbus from personal experience.



In addition to being cautious with rudder; pulling and rolling is something to be aware of as well. If you want to keep positive Gs when upside down, chances are you are going to be loosing altitude and gaining a significant amount of airspeed. Rolling G limits on aerobatic aircraft are typically 2/3s of the positive G limitation on the aircraft.

Perhaps in a jet where there is high momentum, you can get away with rolling and pulling without diving too much. But in a light piston aircraft, you'd better keep that nose close to the horizon.