Aerobatics in non aero aircraft.
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Aerobatics in non aero aircraft.
Whilst reading the Lake Evella thread I read the post from Northern Chicque regarding P68 aeros. If she is who I think she is then I may of been tootling arround in those very same A/C.
From experience, luck seems to favor the stupid and it is invariably the next pilot who hours, days or even months later pays the penalty for someone else's illegal and badly performed manoever.
My sugestion is a thread which maybe reports on known witnessed actions of wrongful aerobatics and then in a subtle way indicate to pruners which a/c to avoid, give extra attention in the preflight or maybe slow down a bit more than usual next time they are in turbulance. And lastly there is always the report to the CP and having a proper inspection performed on the old girl,
they do get a bit of a hammering even without this abuse.
I have never seen any illegal aeros therefore I can not get this thread rolling but I can say that there is at least one twin in the North that I will not want to fly ever again.
From experience, luck seems to favor the stupid and it is invariably the next pilot who hours, days or even months later pays the penalty for someone else's illegal and badly performed manoever.
My sugestion is a thread which maybe reports on known witnessed actions of wrongful aerobatics and then in a subtle way indicate to pruners which a/c to avoid, give extra attention in the preflight or maybe slow down a bit more than usual next time they are in turbulance. And lastly there is always the report to the CP and having a proper inspection performed on the old girl,
they do get a bit of a hammering even without this abuse.
I have never seen any illegal aeros therefore I can not get this thread rolling but I can say that there is at least one twin in the North that I will not want to fly ever again.
Bugsmasherdriverandjediknite
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UUUUUMM, does first flights in an R22 count?, Im sure some of them manouvers I was doing were aerobatic........... I was trying to hover in one spot at the time though. 
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Most Aero Commanders were rolled and looped at least once. By the factory.
When the organisers of the first Skyrace were trying to get approval for Bob Hoover to do a display (this was when he was "medically" delicensed" in the US) CASA (or an earlier incarnation) said that he could but that the aircraft would then be grounded.
Inquiries were made with Hoover who informed the organisers that nearly all Aero Commanders were looped and rolled during the test flight prior to delivery. He also advised a check of the throttle quadrant should reveal two small holes near the throttle levers which was where the temporary accumulators were attached.
An inquiry to an Aero Commander user in Australia (not GAM) revealed that all three of their aircraft had the holes. An inquiry to GAM revealed that they had Bob Hoover's display aircraft in their fleet and the accumulators were sitting on the shelf.
They were subsequently fitted to the aircraft that he flew in Australia.
When advised of this CASA thought it all too much and quietly agreed to the whole thing going ahead.
When the organisers of the first Skyrace were trying to get approval for Bob Hoover to do a display (this was when he was "medically" delicensed" in the US) CASA (or an earlier incarnation) said that he could but that the aircraft would then be grounded.
Inquiries were made with Hoover who informed the organisers that nearly all Aero Commanders were looped and rolled during the test flight prior to delivery. He also advised a check of the throttle quadrant should reveal two small holes near the throttle levers which was where the temporary accumulators were attached.
An inquiry to an Aero Commander user in Australia (not GAM) revealed that all three of their aircraft had the holes. An inquiry to GAM revealed that they had Bob Hoover's display aircraft in their fleet and the accumulators were sitting on the shelf.
They were subsequently fitted to the aircraft that he flew in Australia.
When advised of this CASA thought it all too much and quietly agreed to the whole thing going ahead.
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At the risk of showing my ignorance! Could someone explain to me what part of accumulators (I am assuming unfeathering) might be fitted in two holes on the throttle quadrant of an Aerocommander?
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I'm just guessing but the little holes might have been were the switches stuck out.....
As for aero's in non aerobatic aircraft if done correctly and smoothly I don't see how a roll could damage your average bug smasher. Most of them are rated to around 3 "g's" + and a little over 1"g" - and in a roll (not a flick or a hezy roll) the moist force I could see put on the aircraft would be raising the nose to start ,around 1.5 to 2 +"g" at the most .There is some twisting forces but no more then you would get going into a limit turn quickly. Loop's however could get a little close to + "g" limit a normal comfortable loop for me I will get between 3 and 4 + "g". Again I said if done correctly and keep in mind even Bob and Chuck make mistakes every now and again.
There are also the stories of 747's and the like being rolled and I'm sure we have all seen the picture of the 707 upside down, I personally have seen a HS-748 rolled.
A last little piont Have you ever thought how many "g's" you pull on taxi when you go over a bit of a bump.
As for aero's in non aerobatic aircraft if done correctly and smoothly I don't see how a roll could damage your average bug smasher. Most of them are rated to around 3 "g's" + and a little over 1"g" - and in a roll (not a flick or a hezy roll) the moist force I could see put on the aircraft would be raising the nose to start ,around 1.5 to 2 +"g" at the most .There is some twisting forces but no more then you would get going into a limit turn quickly. Loop's however could get a little close to + "g" limit a normal comfortable loop for me I will get between 3 and 4 + "g". Again I said if done correctly and keep in mind even Bob and Chuck make mistakes every now and again.
There are also the stories of 747's and the like being rolled and I'm sure we have all seen the picture of the 707 upside down, I personally have seen a HS-748 rolled.
A last little piont Have you ever thought how many "g's" you pull on taxi when you go over a bit of a bump.
CDT4,
a slow roll can go pear shaped quickly if the nose is allowed to drop to much over the back. This is where you will then need a lot of G to get the nose back up, especially if you are running out of altitude. You said that they need to be done correctly; a slow roll is one of the easier manoeuvres to stuff up.
This pull will usually be rolling G which is the dangerous part, its a lot more than a limit turn and it is sustained, not a lot of extra back stick to put it over a limit.
The G force felt when hitting a bump is irrelevant, there is no bending moment on the wings.
a slow roll can go pear shaped quickly if the nose is allowed to drop to much over the back. This is where you will then need a lot of G to get the nose back up, especially if you are running out of altitude. You said that they need to be done correctly; a slow roll is one of the easier manoeuvres to stuff up.
This pull will usually be rolling G which is the dangerous part, its a lot more than a limit turn and it is sustained, not a lot of extra back stick to put it over a limit.
The G force felt when hitting a bump is irrelevant, there is no bending moment on the wings.
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Rolling G
This is when one wing is creating more lift thus creating more 'g' than another. So if you think about it, in a four g loop, one wing could be producing up to six g if not symmetric. Not many people are aware of this theory.
Rolling G
There was almost a nasty AD released on the bonanza series after a number of T34 mentor's (the ex US airforce tandem trainer version of the bonanza) lost their wings during mock dogfights.
It appears the clients were rolling and pulling at the same time causing a sudden loss of wings, rather than rolling and then pulling.
Bevan..
It appears the clients were rolling and pulling at the same time causing a sudden loss of wings, rather than rolling and then pulling.
Bevan..
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ftrplt
“a slow roll can go pear shaped quickly” Agreed ,My fault, I was talking about your stock standard aileron roll and I should have stated that.
“This pull will usually be rolling G which is the dangerous part” Agreed again about the rolling “G” but why do you roll when pulling up all this will achieve is to turn the aircraft and therefore loose your line . I was taught to raise the nose then neutralise the control column before the roll. Are you talking about a slow roll or a barrel roll.
“its a lot more than a limit turn and it is sustained” First of all in an aileron roll (or a slow roll for that matter)there isn’t much “G” at all (between 0 and 1) the control column is neutralized so how can it be high and sustained, again are you talking about a slow roll or a barrel roll.
Any way we are getting away from the original question. I think some people could do aerobatics in a non aerobatic aircraft quite safely with out any danger to them selves or the next person flying it but mistakes happen. If everyone practiced good airman ship this wouldn’t be a problem but I suppose in a perfect world we wouldn’t have had a problem to start with.
“a slow roll can go pear shaped quickly” Agreed ,My fault, I was talking about your stock standard aileron roll and I should have stated that.
“This pull will usually be rolling G which is the dangerous part” Agreed again about the rolling “G” but why do you roll when pulling up all this will achieve is to turn the aircraft and therefore loose your line . I was taught to raise the nose then neutralise the control column before the roll. Are you talking about a slow roll or a barrel roll.
“its a lot more than a limit turn and it is sustained” First of all in an aileron roll (or a slow roll for that matter)there isn’t much “G” at all (between 0 and 1) the control column is neutralized so how can it be high and sustained, again are you talking about a slow roll or a barrel roll.
Any way we are getting away from the original question. I think some people could do aerobatics in a non aerobatic aircraft quite safely with out any danger to them selves or the next person flying it but mistakes happen. If everyone practiced good airman ship this wouldn’t be a problem but I suppose in a perfect world we wouldn’t have had a problem to start with.
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Knulp.... yup PN68 fell to bits at an airshow... with the pilots wife calling the routine when it all went horribly wrong. The wings snapped at the outer side of the engine nacelle and wing during a low level pull out of a manouveur.
Further aging of these aircraft have show weaknesses around this area.
Bob - the meer thought of flying those aircraft after what I saw them go through was disheartening to say the least, although this company was a pretty good one compared to others.
Especially when I was detailing one and then again a week later to finish the polish job, I was back up the ladder looking at the top of the wing. Only this time was there a nasty and obvious difference. All the rivets along closest to the nacelle were either lifted or loose, the rivets joining the skin to the main spar were also lifting, one wing worse than the other.
The boss was told, the aircraft grounded, inspected and then sent for a set of spar mods.
Further aging of these aircraft have show weaknesses around this area.
Bob - the meer thought of flying those aircraft after what I saw them go through was disheartening to say the least, although this company was a pretty good one compared to others.
Especially when I was detailing one and then again a week later to finish the polish job, I was back up the ladder looking at the top of the wing. Only this time was there a nasty and obvious difference. All the rivets along closest to the nacelle were either lifted or loose, the rivets joining the skin to the main spar were also lifting, one wing worse than the other.
The boss was told, the aircraft grounded, inspected and then sent for a set of spar mods.
Yeah, great idea, aerobatics in a non-aerobatic aircraft.
Limits are just for pussies!
Rules, schmules...
Great attitude there CDT4.
What about turning a machine upside down when its oil and fuel systems aren't designed to do so?
A bit of insidious oil starvation would be a great thing, cumulatively over time.
Not to mention your non-aerobatic aircraft with its -1.3 g limit; while you're upside down in your aileron roll and hit a bit of turbulence, whoops, probably just overstressed negatively, but wouldn't know because there's no g-meter. Even if you did, you wouldn't report it because you're not supposed to be doing it!
Oh well, nobody will know...
Unfortunately (or fortunately rather) these things have a way of coming out later at the most embarrassing moment.
Limits are just for pussies!
Rules, schmules...
Great attitude there CDT4.
What about turning a machine upside down when its oil and fuel systems aren't designed to do so?
A bit of insidious oil starvation would be a great thing, cumulatively over time.
Not to mention your non-aerobatic aircraft with its -1.3 g limit; while you're upside down in your aileron roll and hit a bit of turbulence, whoops, probably just overstressed negatively, but wouldn't know because there's no g-meter. Even if you did, you wouldn't report it because you're not supposed to be doing it!
Oh well, nobody will know...
Unfortunately (or fortunately rather) these things have a way of coming out later at the most embarrassing moment.
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I was in no way condoning everyone going out and do aero's just saying that some people could e.g. Bob Hover or poeple of simmilar skills and experience .
And by the way lots of aerobatic aircraft don’t have an inverted fuel or oil system.
And by the way lots of aerobatic aircraft don’t have an inverted fuel or oil system.
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Come on boy's, whats the go with the Aerocommander unfeathering acumulators having little holes near the throttles for switches to stick out.
You could put what I know about Commanders on the head of a pin. Maybe they do have Hamilton Standards fitted?
Enlighten me.
You could put what I know about Commanders on the head of a pin. Maybe they do have Hamilton Standards fitted?
Enlighten me.
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Spotlight
The holes were put there when the test pilots at Aero Commander (for a long time Bob Hoover) had unfeathering accumulator switches attached to either the throttles or pitch controls.
It is evidence that those particular aircraft have been rolled and/or looped during the test flight following construction.
The holes were put there when the test pilots at Aero Commander (for a long time Bob Hoover) had unfeathering accumulator switches attached to either the throttles or pitch controls.
It is evidence that those particular aircraft have been rolled and/or looped during the test flight following construction.
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It does not sound like any system I have ever come across, to somehow have the accumulator valve electrically activated.
It might make a bit more sense if there were holes present in the structure to the rear of the engine where the 'optional' unfeathering accumulator would be mounted.
As to how evidence of the previous fitment of unfeathering accumulators tells us that the aircraft were looped and rolled on their test flight following construction, I must admit I am lost.
It might make a bit more sense if there were holes present in the structure to the rear of the engine where the 'optional' unfeathering accumulator would be mounted.
As to how evidence of the previous fitment of unfeathering accumulators tells us that the aircraft were looped and rolled on their test flight following construction, I must admit I am lost.