Unreported light aircraft accident
Thread drift here but very relevant to the topic.
There is one way and one way only if you have no choice but to fly in cloud to get down, for example. You dont need the required IF instruments or IR rated for this. Anyone know?
I await a response with interest. I'll give it a while, if the correct answer is not forth coming I will tell you. This action is not taught at flying schools that I am aware of.
This action could have saved their lives and countless others also I am convinced..
I tried to extract a response to this question years ago. I was dismayed it took so long.
There is one way and one way only if you have no choice but to fly in cloud to get down, for example. You dont need the required IF instruments or IR rated for this. Anyone know?
I await a response with interest. I'll give it a while, if the correct answer is not forth coming I will tell you. This action is not taught at flying schools that I am aware of.
This action could have saved their lives and countless others also I am convinced..
I tried to extract a response to this question years ago. I was dismayed it took so long.
If I recall, this should be the only heading on which a magnetic compass swings the correct way at start of a turn, i.e.., when first starting to bank. Not sure if that would work at light aircraft speeds, even in a CAP 10. I believe it was demonstrated as useful for a military jet deecent, way back when.
...I await a response with interest. I'll give it a while, if the correct answer is not forth coming I will tell you. This action is not taught at flying schools that I am aware of.
This action could have saved their lives and countless others also I am convinced...
This action could have saved their lives and countless others also I am convinced...
Otherwise sad to read of this event, and the various ways the ultimate end could possibly have been avoided. While there appear to be shortcomings with the ATC response, and recognising the probable cognitive overload of the pilot, it begs the question as to whether a more informative/assertive response from the pilot would have been useful?
To tease that out a little more - is there a case to formulate (in training and refresher) a slightly more detailed statement by pilots in such a situation, and/or a specific squawk code for unrated a/c or pilot in IMC? Not wanting to add to the overload, but had there been such training perhaps the pilot may have been better able to respond to ATC's suggestion of an ILS + SRA approach?
FP.
Ok.
You have one chance and one chance only. Use the inherent stability of the Aircraft.
- Carb Heat on, throttle back to approx 1500 RPM
- Trim for approx 70 A/S. Depending on type of course.
- FEET OFF THE RUDDERS!! and leave them off!
- Ailerons central and keep them central.wheel or stick central.
Only instrument needed is ASI
Try it for yourself. Sure the aircraft will wallow around etc. but will get you down.
DID I SAY FEET OFF THE RUDDERS?
You have one chance and one chance only. Use the inherent stability of the Aircraft.
- Carb Heat on, throttle back to approx 1500 RPM
- Trim for approx 70 A/S. Depending on type of course.
- FEET OFF THE RUDDERS!! and leave them off!
- Ailerons central and keep them central.wheel or stick central.
Only instrument needed is ASI
Try it for yourself. Sure the aircraft will wallow around etc. but will get you down.
DID I SAY FEET OFF THE RUDDERS?
Last edited by RichardJones; 28th Apr 2023 at 11:04.
Otherwise sad to read of this event, and the various ways the ultimate end could possibly have been avoided. While there appear to be shortcomings with the ATC response, and recognising the probable cognitive overload of the pilot, it begs the question as to whether a more informative/assertive response from the pilot would have been useful?
FP.
A quick ’fix’ might be for RT training to emphasise with the PAN/MAYDAY first contact pass your details response, that ‘VFR only/IFR capable’ or a suitable simple phrase is added. That way an ATCO knows on first contact the criteria the air system is operating to. A simple procedure like that might have blocked a hole in the Swiss cheese in this instance.
As the pilot was likely maxed out the assertive response was potentially over ruled by the ‘im with D&D tfft’ placebo effect.
A quick ’fix’ might be for RT training to emphasise with the PAN/MAYDAY first contact pass your details response, that ‘VFR only/IFR capable’ or a suitable simple phrase is added. That way an ATCO knows on first contact the criteria the air system is operating to. A simple procedure like that might have blocked a hole in the Swiss cheese in this instance.
A quick ’fix’ might be for RT training to emphasise with the PAN/MAYDAY first contact pass your details response, that ‘VFR only/IFR capable’ or a suitable simple phrase is added. That way an ATCO knows on first contact the criteria the air system is operating to. A simple procedure like that might have blocked a hole in the Swiss cheese in this instance.
The confusion appears to have come between D&D and Exeter ATC.
D&D thought Exeter were asking to be given the aircraft and therefore aware of the situation, when in fact they were just asking about its impact on other emergency traffic they were already working.
The controller assigned the aircraft thought that it had requested a divert to Exeter and was aware of the weather thus assumed that it was IFR capable.
(The above is my take from having skimmed the report rather than read it word for word - so if i'm mistaken then i apologise).
All very sad and I have sympathy for the controllers involved.
OH
Given a significant number of pilots don't know what rudder pedals are for this might be the default response anyway 
Not a bad idea in some situations perhaps, although you'd want to ensure your a/c was rigged well, and not inclined to deviate in this configuration.
Good idea, this is short and to the point and, if trained well, would hopefully survive significant cognitive noise.
Not a bad idea in some situations perhaps, although you'd want to ensure your a/c was rigged well, and not inclined to deviate in this configuration.
This action is not taught at flying schools that I am aware of
It's not just a matter of being stable or unstable. There are degrees of stability. All civil aircraft are designed to be strongly stable in the yawing plane (directional stability), moderately stable in the pitching plane (longitudinal stability) and weakly stable in the rolling plane (lateral stability).
This is a deliberate design characteristic because the other side of the coin is manoeuvrability. Whereas stability is the resistance to change, manoeuvrability is the willingness to change. We don't want the aircraft to resist any attempt to make it roll, but we would like to be happy to maintain direction without the need for constant rudder input.
I'm afraid you wont be able to 'hands off' for long before the aircraft will begin to bank one way or the other. That was the designer's intention.
If the banking tendency is left unattended the bank will continue to increase and then the side-slip will induce a yaw towards the dropping wing. With no control input from the pilot, a spiral dive will result.
This is a deliberate design characteristic because the other side of the coin is manoeuvrability. Whereas stability is the resistance to change, manoeuvrability is the willingness to change. We don't want the aircraft to resist any attempt to make it roll, but we would like to be happy to maintain direction without the need for constant rudder input.
I'm afraid you wont be able to 'hands off' for long before the aircraft will begin to bank one way or the other. That was the designer's intention.
If the banking tendency is left unattended the bank will continue to increase and then the side-slip will induce a yaw towards the dropping wing. With no control input from the pilot, a spiral dive will result.
The aim of my input was to a student or any pilot for that matter, including closed mind know it alls. (The day we stop learning is the day we give up). About how an aircraft if left alone, without pilot interference will fly itself. Goodness me a paper paper glider, trimmed will glide. So why not a trimmed A/C? Sure it will not fly straight, but it will remain flying. I.e., not stall out. That's what kills, the vertical deceleration.. No pilot control input, is better than a WRONG pilot input.
oh and on the subject of credentials, me, 20k hours TT, made up of instructing, ag flying. Bush flying, airline. A lot of types. including heavy 4 engine jets, B747 included. Stuff you dont learn in a classroom. Well retired. Dont have a closed mind but seek solutions. Think before you criticise, or ridicule.
Last edited by RichardJones; 29th Apr 2023 at 08:20.
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Vertical deceleration? Well let's take the EFATO scenario. Turn back, and stall. You die basically. Land ahead. Even if you have obstructions that are unavoidable, you have a good survival chance if the aircraft is under control, I.e. not stalled = high vertical speed. Under control you will do damage, loose wings etc. That will absorb energy of course, however the survival chances are very high. Less vertical deceleration. Stall out is slang for STALLED. OUT of control.
Granted, there are exceptions and variations in weather. Would you be near a T/S in s light A/C?.
However, If one is caught out on top, low on fuel possibly, and having to get down, with all other options exhausted. If you're in it (thick Cloud) you have go get out of it. Last chance saloon. This knowledge may come in handy. How many times have we read that on accident reports?
I am no academic, as you will realise by my writing skills, however I do know a little about aviation. I am also an innovator. I hold a patent.
Fly safe.
Granted, there are exceptions and variations in weather. Would you be near a T/S in s light A/C?.
However, If one is caught out on top, low on fuel possibly, and having to get down, with all other options exhausted. If you're in it (thick Cloud) you have go get out of it. Last chance saloon. This knowledge may come in handy. How many times have we read that on accident reports?
I am no academic, as you will realise by my writing skills, however I do know a little about aviation. I am also an innovator. I hold a patent.
Fly safe.
Last edited by RichardJones; 29th Apr 2023 at 08:31.
Vertical deceleration? Well let's take the EFATO scenario. Turn back, and stall. You die basically. Land ahead.
This action is not taught at flying schools that I am aware of
Getting back to the proposition
it fails to address spiral instability. Spiral instability exists when the static directional stability of the airplane is very strong as compared to the effect of its dihedral in maintaining lateral equilibrium. When the lateral equilibrium of the airplane is disturbed by a gust of air and a side slip is introduced, the strong directional stability tends to yaw the nose into the resultant relative wind while the comparatively weak dihedral lags in restoring the lateral balance. Due to this yaw, the wing on the outside of the turning moment travels forward faster than the inside wing and as a consequence, its lift becomes greater. This produces an over banking tendency which, if not corrected by the pilot, will result in the bank angle becoming steeper and steeper. At the same time, the strong directional stability that yaws the airplane into the relative wind is actually forcing the nose to a lower pitch attitude. Then, the start of a slow downward spiral which has begun, if not counteracted by the pilot, will gradually increase into a steep spiral dive.Usually the rate of divergence in the spiral motion is so gradual that the pilot can control the tendency without any difficulty.
All airplanes are affected to some degree by this characteristic although they may be inherently stable in all other normal parameters. This tendency would be indicated to the pilot by the fact that the airplane cannot be flown "hands off" indefinitely.
Much study and effort has gone into development of control devices (wing leveler) to eliminate or at least correct this instability. Advanced stages of this spiral condition demand that the pilot be very careful in application of recovery controls, or excessive loads on the structure may be imposed.
Of the in-flight structural failures that have occurred in general aviation airplanes, improper recovery from this condition has probably been the underlying cause of more fatalities than any other single factor. The reason is that the airspeed in the spiral condition builds up rapidly, and the application of back elevator force to reduce this speed and to pull the nose up only "tightens the turn," increasing the load factor. The results of the prolonged uncontrolled spiral are always the same; either in-flight structural failure, crashing into the ground, or both. The most common causes on record for getting into this situation are: loss of horizon reference, inability of the pilot to control the airplane by reference to instruments, or a combination of both.
An extract of an article written by Senior Editor Bill Cox of Plane & Pilot and Chief Pilot of an operation who as of January 1, 2016 has logged 15,100 flight hours in 321 types of aircraft.
You have one chance and one chance only. Use the inherent stability of the Aircraft.
- Carb Heat on, throttle back to approx 1500 RPM
- Trim for approx 70 A/S. Depending on type of course.
- FEET OFF THE RUDDERS!! and leave them off!
- Ailerons central and keep them central.wheel or stick central.
Only instrument needed is ASI
Try it for yourself. Sure the aircraft will wallow around etc. but will get you down.
DID I SAY FEET OFF THE RUDDERS?
- Carb Heat on, throttle back to approx 1500 RPM
- Trim for approx 70 A/S. Depending on type of course.
- FEET OFF THE RUDDERS!! and leave them off!
- Ailerons central and keep them central.wheel or stick central.
Only instrument needed is ASI
Try it for yourself. Sure the aircraft will wallow around etc. but will get you down.
DID I SAY FEET OFF THE RUDDERS?
All airplanes are affected to some degree by this characteristic although they may be inherently stable in all other normal parameters. This tendency would be indicated to the pilot by the fact that the airplane cannot be flown "hands off" indefinitely.
Much study and effort has gone into development of control devices (wing leveler) to eliminate or at least correct this instability. Advanced stages of this spiral condition demand that the pilot be very careful in application of recovery controls, or excessive loads on the structure may be imposed.
Of the in-flight structural failures that have occurred in general aviation airplanes, improper recovery from this condition has probably been the underlying cause of more fatalities than any other single factor. The reason is that the airspeed in the spiral condition builds up rapidly, and the application of back elevator force to reduce this speed and to pull the nose up only "tightens the turn," increasing the load factor. The results of the prolonged uncontrolled spiral are always the same; either in-flight structural failure, crashing into the ground, or both. The most common causes on record for getting into this situation are: loss of horizon reference, inability of the pilot to control the airplane by reference to instruments, or a combination of both.
An extract of an article written by Senior Editor Bill Cox of Plane & Pilot and Chief Pilot of an operation who as of January 1, 2016 has logged 15,100 flight hours in 321 types of aircraft.
The Tri-Champ was, above all, ridiculously stable, and that helped to reinforce one of the great private pilot myths of all time.
Tell me you’ve never heard this advice or something resembling it from the instructor’s seat. “OK, now you’re over-controlling. This is an easy airplane to fly. It doesn’t require heavy control inputs in any axis. In fact, it has positive stability. It will fly better than you will. If you trim it properly in a bank or dive and let go of the stick, it will eventually recover to straight-and-level flight all by itself.”
The derivation of this particular brand of nonsense was Civil Aviation Authority Bulletin 32, and instructors took that advice as gospel. After all, it came from the Federal government, so how could it possibly be wrong?
Apparently, not many instructors took the time to test the premise, or they would have discovered in one test that most aircraft of the time were not that stable.
In fact, hardly any aircraft (if any at all) have the kind of positive stability necessary to fly themselves out of a date with disaster. Most of the time, the CG is constantly changing in flight as the aircraft burns off fuel, and lateral stability is especially susceptible to even a moderate wind gust.
The myth was exploded early on when the prestigious Cornell Aeronautical Laboratory of Ithaca, New York, suggested that lack of spiral stability in “the majority of general aviation airplanes!means that the tendency for the airplane to maintain a constant wings-level attitude, if left unattended, is at best marginal.” The Cornell study suggested “the aircraft will enter a turn in which the angle of attack slowly increases and the nose slowly drops with a resultant increase in airspeed! Once the spiral develops (unattended), the airplane will eventually fly into the ground in a spiral dive!.”
Tell me you’ve never heard this advice or something resembling it from the instructor’s seat. “OK, now you’re over-controlling. This is an easy airplane to fly. It doesn’t require heavy control inputs in any axis. In fact, it has positive stability. It will fly better than you will. If you trim it properly in a bank or dive and let go of the stick, it will eventually recover to straight-and-level flight all by itself.”
The derivation of this particular brand of nonsense was Civil Aviation Authority Bulletin 32, and instructors took that advice as gospel. After all, it came from the Federal government, so how could it possibly be wrong?
Apparently, not many instructors took the time to test the premise, or they would have discovered in one test that most aircraft of the time were not that stable.
In fact, hardly any aircraft (if any at all) have the kind of positive stability necessary to fly themselves out of a date with disaster. Most of the time, the CG is constantly changing in flight as the aircraft burns off fuel, and lateral stability is especially susceptible to even a moderate wind gust.
The myth was exploded early on when the prestigious Cornell Aeronautical Laboratory of Ithaca, New York, suggested that lack of spiral stability in “the majority of general aviation airplanes!means that the tendency for the airplane to maintain a constant wings-level attitude, if left unattended, is at best marginal.” The Cornell study suggested “the aircraft will enter a turn in which the angle of attack slowly increases and the nose slowly drops with a resultant increase in airspeed! Once the spiral develops (unattended), the airplane will eventually fly into the ground in a spiral dive!.”
Getting back to the propositionit fails to address spiral instability. Spiral instability exists when the static directional stability of the airplane is very strong as compared to the effect of its dihedral in maintaining lateral equilibrium. When the lateral equilibrium of the airplane is disturbed by a gust of air and a side slip is introduced, the strong directional stability tends to yaw the nose into the resultant relative wind while the comparatively weak dihedral lags in restoring the lateral balance. Due to this yaw, the wing on the outside of the turning moment travels forward faster than the inside wing and as a consequence, its lift becomes greater. This produces an over banking tendency which, if not corrected by the pilot, will result in the bank angle becoming steeper and steeper. At the same time, the strong directional stability that yaws the airplane into the relative wind is actually forcing the nose to a lower pitch attitude. Then, the start of a slow downward spiral which has begun, if not counteracted by the pilot, will gradually increase into a steep spiral dive.Usually the rate of divergence in the spiral motion is so gradual that the pilot can control the tendency without any difficulty.
All airplanes are affected to some degree by this characteristic although they may be inherently stable in all other normal parameters. This tendency would be indicated to the pilot by the fact that the airplane cannot be flown "hands off" indefinitely.
Much study and effort has gone into development of control devices (wing leveler) to eliminate or at least correct this instability. Advanced stages of this spiral condition demand that the pilot be very careful in application of recovery controls, or excessive loads on the structure may be imposed.
Of the in-flight structural failures that have occurred in general aviation airplanes, improper recovery from this condition has probably been the underlying cause of more fatalities than any other single factor. The reason is that the airspeed in the spiral condition builds up rapidly, and the application of back elevator force to reduce this speed and to pull the nose up only "tightens the turn," increasing the load factor. The results of the prolonged uncontrolled spiral are always the same; either in-flight structural failure, crashing into the ground, or both. The most common causes on record for getting into this situation are: loss of horizon reference, inability of the pilot to control the airplane by reference to instruments, or a combination of both.
An extract of an article written by Senior Editor Bill Cox of Plane & Pilot and Chief Pilot of an operation who as of January 1, 2016 has logged 15,100 flight hours in 321 types of aircraft.
All airplanes are affected to some degree by this characteristic although they may be inherently stable in all other normal parameters. This tendency would be indicated to the pilot by the fact that the airplane cannot be flown "hands off" indefinitely.
Much study and effort has gone into development of control devices (wing leveler) to eliminate or at least correct this instability. Advanced stages of this spiral condition demand that the pilot be very careful in application of recovery controls, or excessive loads on the structure may be imposed.
Of the in-flight structural failures that have occurred in general aviation airplanes, improper recovery from this condition has probably been the underlying cause of more fatalities than any other single factor. The reason is that the airspeed in the spiral condition builds up rapidly, and the application of back elevator force to reduce this speed and to pull the nose up only "tightens the turn," increasing the load factor. The results of the prolonged uncontrolled spiral are always the same; either in-flight structural failure, crashing into the ground, or both. The most common causes on record for getting into this situation are: loss of horizon reference, inability of the pilot to control the airplane by reference to instruments, or a combination of both.
An extract of an article written by Senior Editor Bill Cox of Plane & Pilot and Chief Pilot of an operation who as of January 1, 2016 has logged 15,100 flight hours in 321 types of aircraft.
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This seems like a situation that could been fairly easy to resolve, depending on the cloud at his high altitude when he called ATC. We know he reported being on top of cloud but cannot be sure if it was a large swath of good VFR on top conditions or not(it would have been nice for the air to get a pirep from the nearby military jet).
The pilot had decent flight experience at over 1000 hours. He also had options with 1.5 hours fuel stated to ATC(and depending on what power setting he based it on, could have been extended). All that need to have been done was to ask ATC about weather reports at nearby airports. There were airports within 1.5 hours that had very nice weather. A request for vectors would get him to a safe airport.
Even if an unavoidable cloud layer was encountered, I would suggest that it would likely be safer to penetrate IMC in cruise flight rather than what likely turned out to be a descent at a speed closer to the redline.
And even if he ended up out of non-IMC options with low fuel over an airport with an overcast layer combined with a cloud base that was not too low, he could have put his aerobatic plane in a spin and held it there until clear of the clouds, then recovered.
The pilot had decent flight experience at over 1000 hours. He also had options with 1.5 hours fuel stated to ATC(and depending on what power setting he based it on, could have been extended). All that need to have been done was to ask ATC about weather reports at nearby airports. There were airports within 1.5 hours that had very nice weather. A request for vectors would get him to a safe airport.
Even if an unavoidable cloud layer was encountered, I would suggest that it would likely be safer to penetrate IMC in cruise flight rather than what likely turned out to be a descent at a speed closer to the redline.
And even if he ended up out of non-IMC options with low fuel over an airport with an overcast layer combined with a cloud base that was not too low, he could have put his aerobatic plane in a spin and held it there until clear of the clouds, then recovered.
Thread drift here but very relevant to the topic.
There is one way and one way only if you have no choice but to fly in cloud to get down, for example. You dont need the required IF instruments or IR rated for this. Anyone know?
I await a response with interest. I'll give it a while, if the correct answer is not forth coming I will tell you. This action is not taught at flying schools that I am aware of.
This action could have saved their lives and countless others also I am convinced..
I tried to extract a response to this question years ago. I was dismayed it took so long.
There is one way and one way only if you have no choice but to fly in cloud to get down, for example. You dont need the required IF instruments or IR rated for this. Anyone know?
I await a response with interest. I'll give it a while, if the correct answer is not forth coming I will tell you. This action is not taught at flying schools that I am aware of.
This action could have saved their lives and countless others also I am convinced..
I tried to extract a response to this question years ago. I was dismayed it took so long.
Under US glider competition rules it is prohibited to have any sort of blind flying instrument. Both my standard class gliders had a stable spiral descent with hands off the stick, feet off the rudder pedals, and full air brake. So, certainly some aircraft can be safely descended in IMC if the primary controls are left alone.
I have not experimented with long term hands and feet off stability in the airplanes I have owned. I'm instrument rated and keep current so I'd rather fly on instruments.
From this accident report there appears to have been no reason for the pilot to have entered IMC. With 1.5 hours duration there was lots of time to come up with a better plan.
I have not experimented with long term hands and feet off stability in the airplanes I have owned. I'm instrument rated and keep current so I'd rather fly on instruments.
From this accident report there appears to have been no reason for the pilot to have entered IMC. With 1.5 hours duration there was lots of time to come up with a better plan.
“And even if he ended up out of non-IMC options with low fuel over an airport with an overcast layer combined with a cloud base that was not too low, he could have put his aerobatic plane in a spin and held it there until clear of the clouds, then recovered.”
Per the report, Exeter was 500 BKN, 6 km.
Per this aircraft’s POH, it loses 400ft/turn in a perfectly executed spin when loaded to Aerobatic specifications (it wasn’t)
Tell us how that works for you.
On the other hand, the report also says the aircraft was equipped with a functional Bendix Attitude Indicator.
Maybe there was a better option…
Per the report, Exeter was 500 BKN, 6 km.
Per this aircraft’s POH, it loses 400ft/turn in a perfectly executed spin when loaded to Aerobatic specifications (it wasn’t)
Tell us how that works for you.
On the other hand, the report also says the aircraft was equipped with a functional Bendix Attitude Indicator.
Maybe there was a better option…
Last edited by 421dog; 30th Apr 2023 at 22:10.