Fatal reported Central Otago, NZ
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With regard to my comment about airspeed if you were in a Pitts and recovered from an upright stall by putting full forward stick you would stall the wings with a negative angle of attack and almost definately end up in an inverted spin
I can demonstrate a stall in a fixed wing at any speed from zero knots up to Vne
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Brian,
I dont want to waste too much of my time responding to tit for tat responses. You have shown a lack of understand of aerodynamics. No big deal but its useful to understand things in more detail.
One point I am making is that one should NOT assume that an experienced fixed-wing pilot will resort to ham fisted incorrect responses in an emergency.
Another point I am making is that the stall of an airfoil doesnt always happen at a certain speed but can happen at virtually any speed. But always at or beyond the stall angle of attack.
We have all studied the vector diagrams that show how autorotative forces work. Its all about angle of attack of the airfoil.
Nuff said.
OOW
I dont want to waste too much of my time responding to tit for tat responses. You have shown a lack of understand of aerodynamics. No big deal but its useful to understand things in more detail.
One point I am making is that one should NOT assume that an experienced fixed-wing pilot will resort to ham fisted incorrect responses in an emergency.
Another point I am making is that the stall of an airfoil doesnt always happen at a certain speed but can happen at virtually any speed. But always at or beyond the stall angle of attack.
We have all studied the vector diagrams that show how autorotative forces work. Its all about angle of attack of the airfoil.
Nuff said.
OOW
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Ok for the sake of completeness:
Given sufficient elevator control authority one could cause a stall in a fixed wing aircraft at any attainable speed. I.e from just over zero knots to beyond Vne. However don't try this unless you are in an aerobatic category aircraft for which you are fully rated and at sufficient height and wearing a parachute. Do not try this above the maneuvering airspeed limitation otherwise you may exceed the design limitations of the aircraft or yourself.
I would happily demonstrate a stall at up to maneuvering airspeed but not beyond as that could overstress the aircraft and might only be performed once.
Given sufficient elevator control authority one could cause a stall in a fixed wing aircraft at any attainable speed. I.e from just over zero knots to beyond Vne. However don't try this unless you are in an aerobatic category aircraft for which you are fully rated and at sufficient height and wearing a parachute. Do not try this above the maneuvering airspeed limitation otherwise you may exceed the design limitations of the aircraft or yourself.
I would happily demonstrate a stall at up to maneuvering airspeed but not beyond as that could overstress the aircraft and might only be performed once.
Last edited by outofwhack; 12th Nov 2012 at 00:30.
OOW: "One point I am making is that one should NOT assume that an experienced fixed-wing pilot will resort to ham fisted incorrect responses in an emergency."
Who made such an assumption? As far as I can tell you are the only one introducing ham-fistedness into this discussion. I certainly never mentioned nor implied it.
No overcontrolled ham-fistedness is required to stall the blades of an R22. However a certain degree of control, correct procedure and *instant* reaction is required to prevent stalling the blades in an engine failure. The more experience a RW pilot has, the faster and more automatic the correction action will be - surely this is all obvious?
The correct action in a FW engine failure is to nose down to maintain glide speed. No overcontrolling required or implied. However taking this action in an R22, with a delay in lowering collective, is likely to be fatal.
I can't see why any of this would be interpreted as a criticism of the pilot in question.
Who made such an assumption? As far as I can tell you are the only one introducing ham-fistedness into this discussion. I certainly never mentioned nor implied it.
No overcontrolled ham-fistedness is required to stall the blades of an R22. However a certain degree of control, correct procedure and *instant* reaction is required to prevent stalling the blades in an engine failure. The more experience a RW pilot has, the faster and more automatic the correction action will be - surely this is all obvious?
The correct action in a FW engine failure is to nose down to maintain glide speed. No overcontrolling required or implied. However taking this action in an R22, with a delay in lowering collective, is likely to be fatal.
I can't see why any of this would be interpreted as a criticism of the pilot in question.
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Look gentleman, the posts stating a wing can stall from VNE to zero indicated (actually calibrated) airspeed is absolutely true. It may be hard to demonstrate at VNE because the aircraft may sustain structural problems 1st however we do demonstrate a stall called an accelerated stall (google it) which is well above level flight un accelerated stall speed. On the flip side just because you have zero indicated (actually calibrated) airspeed does not automatically mean that you are stalled. An example of that would be a zero G pushover from a nose up position to nose down wings level. It is all about angle of attack and managing it. I think everybody here has that knowledge but it takes time to realize it.
I want to add that you can also stall at any attitude. Straight up, down, inverted, it does not matter however obviously some are easier than others. It is all about pointing the nose (in the pitch axis) in the direction the plane is moving. This reduces the angle of attack. Sometimes bringing the nose down will stall the airplane. Check this out; For example the top of the loop where you are past vertical. Most beginners will there pull a bit hard to force the nose down towards the horizon. In the position most aircraft is probably slow and pulling back on the stick to bring the nose down will sometimes exceed the critical angle of attack. How to avoid it? Relax a bit of back pressure usually works So there was an example of exceeding the critical angle of attack while trying to move the nose down a bit to fast. One more example; You are in a fully developed spin, you reduce power, you center the ball as you roll level however if you rush the recovery by bringing the nose up too fast it can easily stall again, during high indicated airspeed and the nose well down. This is an accelerated stall.
Of course almost all of this is irrelevant here being the R22 series is probably a POS (never flown one so I don't really know) and we were not there in the cockpit at the time of the accident so we don't absolutely know what happened there either. However we do know that up until the point where he died he tried everything his experience enabled him to try.
The 2 worst things for a pilot is walking out to the aircraft not knowing it will be your last flight and walking out to the aircraft knowing it will be your last flight.
Think on it.
Another point I am making is that the stall of an airfoil doesn't always happen at a certain speed but can happen at virtually any speed. But always at or beyond the stall angle of attack.
Of course almost all of this is irrelevant here being the R22 series is probably a POS (never flown one so I don't really know) and we were not there in the cockpit at the time of the accident so we don't absolutely know what happened there either. However we do know that up until the point where he died he tried everything his experience enabled him to try.
The 2 worst things for a pilot is walking out to the aircraft not knowing it will be your last flight and walking out to the aircraft knowing it will be your last flight.
Think on it.
Last edited by before landing check list; 12th Nov 2012 at 16:28.
Back to the topic,
"The helicopter pilot killed in a central Otago crash last night was a well-known aviator renowned for being safety-conscious."
Helicopter crash victim 'incredibly safe and experienced' - National News | TVNZ
.
"The helicopter pilot killed in a central Otago crash last night was a well-known aviator renowned for being safety-conscious."
Helicopter crash victim 'incredibly safe and experienced' - National News | TVNZ
.
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Before the R22 bashing gets too much traction, the accident appears to have occurred at night yet we are accepting an 'eye witness' who claims
TVNZ
"A witness had been watching the helicopter as it flew through the Cardrona Valley, looked away, heard a bang, looked back and essentially saw the helicopter falling from the sky without the rotors moving," said Wanaka Police SAR co-ordinator Sergeant Aaron Nicholson.
"Weather conditions were great. It was a fairly calm, clear night so it would appear that, obviously it's not for me to say, but it (weather) doesn't seem to be a factor in what happened," said Nicholson.
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Nonetheless I'm a bit nonplussed that an eyewitness can claim that they saw it falling with the blades not moving. Certainly not something on which I would place too much credibility, much better to wait for the accident investigation; or some on site photos to indicate what condition the blades were in at impact.
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Thanks to subscribers BeforeLandingCheckList, PittsExtra and NotNightOwl for the back up
Father Abraham said my recent statements were
and I had
Funny...I've been flying 30 years, pic in 30+ types in power fw, sailplanes, helicopters, in 3 separate countries and even owned one or two aircraft of each type over my time and won't ever finish learning. Occasionally I meet people who have.
I have noted that more often than not people flying in one discipline have low opinions of people in the others. Sad - we have a passion in common and could learn from each other.
I recall a lecture one year at Oshkosh, Budd Davison said he once flight checked a pilot and wanted to ask "is your 10000 hours the same hour repeated ten thousand times?". In my words - you really can't know all about flying if you haven't had really varied flying experience?
OOW
Father Abraham said my recent statements were
so ridiculous as to not be worth commenting on
absolutely no understanding of fix wing aviation, and you are certainly not an individual who has any practical aviation experience
I have noted that more often than not people flying in one discipline have low opinions of people in the others. Sad - we have a passion in common and could learn from each other.
I recall a lecture one year at Oshkosh, Budd Davison said he once flight checked a pilot and wanted to ask "is your 10000 hours the same hour repeated ten thousand times?". In my words - you really can't know all about flying if you haven't had really varied flying experience?
OOW
Last edited by outofwhack; 13th Nov 2012 at 01:48.
Knowing both OOW and Brian, I can only put this down to an initial misunderstanding which (like Topsy) has grown: out of all proportion!
They're both very experienced aviators in their own fields and would have a good chat over a beer, as long as they include me in the shout
They're both very experienced aviators in their own fields and would have a good chat over a beer, as long as they include me in the shout
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You're welcome OOW, I've a little experience in commercial helicopter flying (and a tiny bit in the R22, it didn't impress me much), these days I charge around for an airline.
Helicopters were fun, had some interesting times.
Helicopters were fun, had some interesting times.
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outofwhack, first let me apologise for being so doubtful of your background.
To be honest, I find statements such as being able to demonstrate a stall at Vne somewhat egregious (I had you down as a sciolist), particularly knowing now it does come from an experienced aviator. The reason being that Pprune has viewers who, through lack of experience or level of knowledge, take what they read here as gospel. As always though, the trouble with communication, especially with the written word, is the impression that it has taken place. As experienced as you seem, it may have been better if the claim was made in more circumspect terms, such as, a wing can stall irrespective of speed.
Both you and I know the facts re angle of attack and associated aerodynamics, but it is not possible to demonstrate a stall in any aircraft at Vne, Pitts included (stressed +6/-3 to +6/-5 depending on model - not 20 as you alluded to, Extra300 is +10/-10 with one up, and +8/-8 two up). Va (which varies with weight, as in the Extra variation quoted) is the speed at which a stall (accelerated obviously) will generate the limit g load. Any speed in excess of Va at which a stall is made will generate a g load in excess of the design and certified g limit. So doing may incur damage, and you know not where. In the Pitts damage is often found during maintenance, and various pilots readily admit to taking them up to +8, which is 1 g short of the ultimate load. Little wonder damage is found. It recently cost a Pitts owner $160,000 to rectify such damage. A stall in the Pitts at Vne will exceed the ultimate load by a little over 1.4 g.
Certification requirement re limit and ultimate loads.
§ FAR 23.305 Strength and deformation.
(a) The structure must be able to support limit loads without detrimental, permanent deformation. At any load up to limit loads, the deformation may not interfere with safe operation.
(b) The structure must be able to support ultimate loads without failure for at least three seconds, except local failures or structural instabilities between limit and ultimate load are acceptable only if the structure can sustain the required ultimate load for at least three seconds. However when proof of strength is shown by dynamic tests simulating actual load conditions, the three second limit does not apply.
Some info re the Pitts
http://freestyleaviation.co.uk/Frees...nual2011v1.pdf
An oft quoted quote. However some individuals dedicate themselves to a specific arena of the profession. It may be as a fixed wing aircraft carrier pilot, airline pilot, aero club instructor, competition aerobatic pilot, EMS helicopter pilot, SAR helicopter pilot, crop duster, offshore helicopter pilot, etc etc It is a trite and glib statement that detracts from the people who ply their trade in a particular, and by definition, narrow spectrum in which they apply their aeronautical skills. Professionals all, and we may dream from time to time of trading places and wondering if we might have, or be able to develop, the skills to make a fist of it. Each has its own demands, and retaining proficiency does not come easily.
I hope that explains. Robust discussion never hurts, even though at the end of the day you may retain your differences.
To be honest, I find statements such as being able to demonstrate a stall at Vne somewhat egregious (I had you down as a sciolist), particularly knowing now it does come from an experienced aviator. The reason being that Pprune has viewers who, through lack of experience or level of knowledge, take what they read here as gospel. As always though, the trouble with communication, especially with the written word, is the impression that it has taken place. As experienced as you seem, it may have been better if the claim was made in more circumspect terms, such as, a wing can stall irrespective of speed.
Both you and I know the facts re angle of attack and associated aerodynamics, but it is not possible to demonstrate a stall in any aircraft at Vne, Pitts included (stressed +6/-3 to +6/-5 depending on model - not 20 as you alluded to, Extra300 is +10/-10 with one up, and +8/-8 two up). Va (which varies with weight, as in the Extra variation quoted) is the speed at which a stall (accelerated obviously) will generate the limit g load. Any speed in excess of Va at which a stall is made will generate a g load in excess of the design and certified g limit. So doing may incur damage, and you know not where. In the Pitts damage is often found during maintenance, and various pilots readily admit to taking them up to +8, which is 1 g short of the ultimate load. Little wonder damage is found. It recently cost a Pitts owner $160,000 to rectify such damage. A stall in the Pitts at Vne will exceed the ultimate load by a little over 1.4 g.
Certification requirement re limit and ultimate loads.
§ FAR 23.305 Strength and deformation.
(a) The structure must be able to support limit loads without detrimental, permanent deformation. At any load up to limit loads, the deformation may not interfere with safe operation.
(b) The structure must be able to support ultimate loads without failure for at least three seconds, except local failures or structural instabilities between limit and ultimate load are acceptable only if the structure can sustain the required ultimate load for at least three seconds. However when proof of strength is shown by dynamic tests simulating actual load conditions, the three second limit does not apply.
Some info re the Pitts
http://freestyleaviation.co.uk/Frees...nual2011v1.pdf
is your 10000 hours the same hour repeated ten thousand times
I hope that explains. Robust discussion never hurts, even though at the end of the day you may retain your differences.
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Thanks for turning a thread about a pilot dying in an R22 crash into a stupid "pizzing contest".
Can't wait to read more about how fast you can stall a freaking Pitts.
Show some respect guys, start another thread if you're going to dribble on like this.
RIP Julianne
Can't wait to read more about how fast you can stall a freaking Pitts.
Show some respect guys, start another thread if you're going to dribble on like this.
RIP Julianne
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TTBB, I see from your posts you are some what given to mouthing off and telling posters
and having your posts pulled by the Mods. If you want to start a condolences thread go ahead. No pissing contest, if you don't like what you read, do what you would watching TV, change channels, or is that beyond your skill set?
instead its been taken over by a couple of loud mouths....quickly drowned out by these two know it all idiots.
FH1100 and Sasless should put a sock in it and let the guys that know tell it.
FH1100 and Sasless should put a sock in it and let the guys that know tell it.