AF 447 Thread No. 10
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I'm pretty sure I stated my opinion the first time CONF iture posted that video, which if I recall correctly was along the lines of - he's as welcome to his opinion as anyone, and his feat of flying certainly means that opinion will have clout and I for one am in awe of what he pulled off. Nevertheless, I disagree with aspects of it on the grounds that there have been several instances of pulling into stall (at least one of which involved UAS) where the presence of a linked PFC had no effect on the outcome.
You may well ask who the hell I am to hold such an opinion, and the answer is "nobody". But the fact is that the argument stating linked controls will prevent a situation where one pilot pulls back into a stall and the other does nothing is demonstrably untrue.
Clandestino
I have repeatedly warned against trying to build advanced theories while having no firm grasp on the basics. It was a win-win proposal for me.
Folks listen to me, bandwidth wastage gets reduced.
Folks disregard, I'm kept entertained.
For those unable to take subtle hints:
I have repeatedly warned against trying to build advanced theories while having no firm grasp on the basics. It was a win-win proposal for me.
Folks listen to me, bandwidth wastage gets reduced.
Folks disregard, I'm kept entertained.
For those unable to take subtle hints:
Originally Posted by Retired F4
This returniung to the altitude was imho exactly what the PF tried, smooth and easy and no coffee cups on the floor and no passenger complaint.
Clandestino
First, that's not the way it works in the real life because a) pilots are trained to put safety before comfort b) other similar incidents have shown a) is observed in real life for most of the time by most of the crews.
This returniung to the altitude was imho exactly what the PF tried, smooth and easy and no coffee cups on the floor and no passenger complaint.
Clandestino
First, that's not the way it works in the real life because a) pilots are trained to put safety before comfort b) other similar incidents have shown a) is observed in real life for most of the time by most of the crews.
Clandestino
Third, calling sidestick movements recorded on FDR smooth and easy is not something I'd do but then it could be my level 2 English.
Third, calling sidestick movements recorded on FDR smooth and easy is not something I'd do but then it could be my level 2 English.
Quote:
Originally Posted by Retired F4
The necessary recovery action was time critical.
Clandestino
True, but it was not even initiated.
Originally Posted by Retired F4
The necessary recovery action was time critical.
Clandestino
True, but it was not even initiated.
BEA Final report, bolding by me
The PNF’s intervention prompted the PF to apply inputs that reduced the pitch attitude, which had exceeded 10 degrees. Although the PF agreed that the objective should be to lose altitude, his inputs maintained the aeroplane on an ascending flight path. The crossbar then indicated a pitch-up input, which did not stimulate him to make sufficient pitch-down inputs to satisfy the PNF’s request. On his side, the PF checked the position of the thrust levers (“We are in, yeah, we are in climb”) then six seconds later reduced the thrust.
The PNF had noticed the need to stabilise the flight path, and the need for moderate aeroplane handling inputs. He probably considered that the reduction in pitch and the vertical acceleration sensed was a sufficient sign that the PF would correct the flight path to allow him to devote himself once again to identifying the failure.
The PNF’s intervention prompted the PF to apply inputs that reduced the pitch attitude, which had exceeded 10 degrees. Although the PF agreed that the objective should be to lose altitude, his inputs maintained the aeroplane on an ascending flight path. The crossbar then indicated a pitch-up input, which did not stimulate him to make sufficient pitch-down inputs to satisfy the PNF’s request. On his side, the PF checked the position of the thrust levers (“We are in, yeah, we are in climb”) then six seconds later reduced the thrust.
The PNF had noticed the need to stabilise the flight path, and the need for moderate aeroplane handling inputs. He probably considered that the reduction in pitch and the vertical acceleration sensed was a sufficient sign that the PF would correct the flight path to allow him to devote himself once again to identifying the failure.
Clandestino
Even if they went to Climb thrust/5° pitch at the apex of their climb, aeroplane would stabilize at alpha slightly above 5° and perform gentle driftdown to 5° alpha ceiling.
It is not as important to know the reason and principles involved in procedures ............ just that many a pilot had successful and long flying carrier while being oblivious to some basic flying facts.
Even if they went to Climb thrust/5° pitch at the apex of their climb, aeroplane would stabilize at alpha slightly above 5° and perform gentle driftdown to 5° alpha ceiling.
It is not as important to know the reason and principles involved in procedures ............ just that many a pilot had successful and long flying carrier while being oblivious to some basic flying facts.
BEA final report, bolding by me
In the absence of reliable speed indication, an understanding of the physics of high-altitude flying, gained through training in the fundamental principles of energy conversion, equilibriums of forces, and lift and propulsion ceilings, could have considerably helped the pilots to anticipate the rapid deterioration in their situation and to take the appropriate corrective measure in time: initiate a descent.
In the absence of reliable speed indication, an understanding of the physics of high-altitude flying, gained through training in the fundamental principles of energy conversion, equilibriums of forces, and lift and propulsion ceilings, could have considerably helped the pilots to anticipate the rapid deterioration in their situation and to take the appropriate corrective measure in time: initiate a descent.
Clandestino
Pushing the stick full forward on Airbus gives you -1G clean (and fast enough, about which there was no doubt when second stall warning went off). That's enough enough. Now watch the ignorant bite on this one.
Pushing the stick full forward on Airbus gives you -1G clean (and fast enough, about which there was no doubt when second stall warning went off). That's enough enough. Now watch the ignorant bite on this one.
Clandestino
Because they are absolutely inessential in transporter! We might install them one day when we go seriously about the business of air combat in A330 but I can't see it happening anytime soon.
Because they are absolutely inessential in transporter! We might install them one day when we go seriously about the business of air combat in A330 but I can't see it happening anytime soon.
BEA Final report, bolding by me
It is essential in order to ensure flight safety to reduce the angle of attack when a stall is imminent. Only a direct readout of the angle of attack could enable crews to rapidly identify the aerodynamic situation of the aeroplane and take the actions that may be required.
Consequently, the BEA recommends:
- that EASA and the FAA evaluate the relevance of requiring the presence of an angle of attack indicator directly accessible to pilots on board aeroplanes.
It is essential in order to ensure flight safety to reduce the angle of attack when a stall is imminent. Only a direct readout of the angle of attack could enable crews to rapidly identify the aerodynamic situation of the aeroplane and take the actions that may be required.
Consequently, the BEA recommends:
- that EASA and the FAA evaluate the relevance of requiring the presence of an angle of attack indicator directly accessible to pilots on board aeroplanes.
Last edited by RetiredF4; 4th Nov 2012 at 11:46.
Originally Posted by Retired F4
New message there, pilots always do what they are trained for? Are they trained to crash too like AF447?
Well that's the point! The crew was trained to recognize and deal with UAS, they didn't follow the training. Now that in itself is a moot issue as before any abnormals aeroplane has to be under positive and proper control, which it turned out not to be. AF machines suffered from UAS before, it was the first and only that crashed.
Originally Posted by Retired F4
That s not what i do and nothing i said. , but what the PF intended to do and was not able to because of lack of manual flying expierience in FL 350 in ALT2B law.
Originally Posted by Retired F4
Then you have an different explanation for the reduction of V/S, Nz , for the SS being ND until 3 sec. before SW 2 ?
Originally Posted by Retired F4
You are entiteled to contact BEA and tell them your point of view, especially the misuse of the unreliable airspeed procedure which would have worked well after AP-disconnect, as an high altitude approach to stall recovery procedure.
Originally Posted by Retired F4
As you make yourself an expert in ACM, please note, that -1g (full ND SS) produces nearly the same drag as +2g and would be not suitable to regain energy.
Loss of energy during climb in airliner is not the same as the loss of energy during maneuvering a fighter and same procedures need not be applicable.
Anyway, figure 64 of the French report shows the calculated trajectory of the aeroplane without any crew input, demonstrating that even doing absolutely nothing would lead to much better outcome than what the crew did.
As for investigating authorities, they make recommendations, based on the accident/incident they investigated and are not required to estimate the overall impact of them. That's something for manufacturers and aviation authorities to do (and is reason enough to keep investigating bodies independent). Their response might be acceptance, reject or anything in-between and gets classified by investigators as acceptable or unacceptable. Now, installing the AoA gauge seems to be the way to go to BEA but then EASA might point out that a) other crews reduced AoA in UAS situation when stall warning went off b) thousand upon thousands of civil aeroplanes are flown successfully every day without AoA gauge so the reccomendation is rejected. It is possible that compromise solution will be found with visual stall warning. It is possible recommendation will be accepted, we'll get gauges and new training procedures grafted onto existing ones. We shall see what we shall see.
It's interesting 'hearing' a fighter guy talk about airliners and an airline guy talk about fighters (and I mean that in a complimentary way to both).
When going from a 727 flight in the morning, across town to an F-16 flight in the afternoon, I occasionally had the feeling that I should stop off at a phone-booth and change from Clark Kent to you know who.
In absolute terms, they are indeed different worlds, but aviation best practices span them both.
When going from a 727 flight in the morning, across town to an F-16 flight in the afternoon, I occasionally had the feeling that I should stop off at a phone-booth and change from Clark Kent to you know who.
In absolute terms, they are indeed different worlds, but aviation best practices span them both.
Originally Posted by Retired F4
Then you have an different explanation for the reduction of V/S, Nz , for the SS being ND until 3 sec. before SW 2 ?
Clandestino
Simple. Airbus 330 is not F-4. Proper recovery action is not unloading but achieving stable attitude and power and then recovering the altitude (if affected at all). CM2 never achieved anything like it. He made a half-hearted attempt to reduce climb but even before he achieved anything like useful pitch, he reversed into pulling again into insane attitude for the altitude they were flying at. Insane for A330, not F-4, that is.
Then you have an different explanation for the reduction of V/S, Nz , for the SS being ND until 3 sec. before SW 2 ?
Clandestino
Simple. Airbus 330 is not F-4. Proper recovery action is not unloading but achieving stable attitude and power and then recovering the altitude (if affected at all). CM2 never achieved anything like it. He made a half-hearted attempt to reduce climb but even before he achieved anything like useful pitch, he reversed into pulling again into insane attitude for the altitude they were flying at. Insane for A330, not F-4, that is.
BEA Final report, bolding by me
The PNF’s intervention prompted the PF to apply inputs that reduced the pitch attitude, which had exceeded 10 degrees. Although the PF agreed that the objective should be to lose altitude, his inputs maintained the aeroplane on an ascending flight path. The crossbar then indicated a pitch-up input, which did not stimulate him to make sufficient pitch-down inputs to satisfy the PNF’s request. On his side, the PF checked the position of the thrust levers (“We are in, yeah, we are in climb”) then six seconds later reduced the thrust.
The PNF had noticed the need to stabilise the flight path, and the need for moderate aeroplane handling inputs. He probably considered that the reduction in pitch and the vertical acceleration sensed was a sufficient sign that the PF would correct the flight path to allow him to devote himself once again to identifying the failure.
The PNF’s intervention prompted the PF to apply inputs that reduced the pitch attitude, which had exceeded 10 degrees. Although the PF agreed that the objective should be to lose altitude, his inputs maintained the aeroplane on an ascending flight path. The crossbar then indicated a pitch-up input, which did not stimulate him to make sufficient pitch-down inputs to satisfy the PNF’s request. On his side, the PF checked the position of the thrust levers (“We are in, yeah, we are in climb”) then six seconds later reduced the thrust.
The PNF had noticed the need to stabilise the flight path, and the need for moderate aeroplane handling inputs. He probably considered that the reduction in pitch and the vertical acceleration sensed was a sufficient sign that the PF would correct the flight path to allow him to devote himself once again to identifying the failure.
Clandestino
I wasn't discussing stall recovery at all, just UAS. Is there any doubt that stall was brought on by CM2's completely inappropriate reaction? Well, I did warn about need to understand the matter discussed to have meaningful debate.
I wasn't discussing stall recovery at all, just UAS. Is there any doubt that stall was brought on by CM2's completely inappropriate reaction? Well, I did warn about need to understand the matter discussed to have meaningful debate.
Definition of aeroplane upset, Bolding by me
Aerodynamic principles applied to large, swept-wing commercial jet airplanes are similar among all manufacturers, and the recommended techniques for recovering from an upset in an airplane subject to these principles are also compatible. Pilots who understand the conditions of an upset, though such an event is unlikely, will be better prepared to recover from it. The four conditions that generally describe an airplane upset (figure 1) are unintentional:
Pitch attitude more than 25 degrees nose up.
Pitch attitude more than 10 degrees nose down.
Bank angle more than 45 degrees.
Flight within these parameters at airspeeds inappropriate for the conditions.
Aerodynamic principles applied to large, swept-wing commercial jet airplanes are similar among all manufacturers, and the recommended techniques for recovering from an upset in an airplane subject to these principles are also compatible. Pilots who understand the conditions of an upset, though such an event is unlikely, will be better prepared to recover from it. The four conditions that generally describe an airplane upset (figure 1) are unintentional:
Pitch attitude more than 25 degrees nose up.
Pitch attitude more than 10 degrees nose down.
Bank angle more than 45 degrees.
Flight within these parameters at airspeeds inappropriate for the conditions.
And from the BEA report, bolding by me
The excessive amplitude of these inputs made them unsuitable and incompatible with the recommended aeroplane handling practices for high altitude flight.
The excessive amplitude of these inputs made them unsuitable and incompatible with the recommended aeroplane handling practices for high altitude flight.
Clandestino
I have already mentioned that a pilot can have a very successful career just by doing as trained and as written in manuals without having a grasp on the basics.
I have already mentioned that a pilot can have a very successful career just by doing as trained and as written in manuals without having a grasp on the basics.
Clandestino
He made a half-hearted attempt to reduce climb ..
He made a half-hearted attempt to reduce climb ..
It was half hearted or not enough, whatever you call it, and that is exactly what i said and what you needed to comment on with:
Clandestino True, but it was not even initiated.
Clandestino
Loss of energy during climb in airliner is not the same as the loss of energy during maneuvering a fighter and same procedures need not be applicable.
Loss of energy during climb in airliner is not the same as the loss of energy during maneuvering a fighter and same procedures need not be applicable.
But loss of inapropriate amount of energy or better like in this case the exchange from kinetic energy (speed) into potential energy (altitude) causes the same problems in all aircraft, if the altitude exceeds the service ceiling of the aircraft for the given GW and the given flight circumstances.
Clandestino
Anyway, figure 64 of the French report shows the calculated trajectory of the aeroplane without any crew input, demonstrating that even doing absolutely nothing would lead to much better outcome than what the crew did
Anyway, figure 64 of the French report shows the calculated trajectory of the aeroplane without any crew input, demonstrating that even doing absolutely nothing would lead to much better outcome than what the crew did
Clandestino concerning AO
We shall see what we shall see
As they are already available (customer option, BUSS) and needn´t being newly developped, and as there is no known difficult training at the moment for those who bought that option i´d say:
We will see it in the coming aircraft, and some although not all aircraft will be retrofitted.
OK465
It's interesting 'hearing' a fighter guy talk about airliners and an airline guy talk about fighters (and I mean that in a complimentary way to both).
It's interesting 'hearing' a fighter guy talk about airliners and an airline guy talk about fighters (and I mean that in a complimentary way to both).
If you allow me to give your post a personal touch from my POV, than it would look like that: (bolding my insertions)
It's interesting 'hearing' a old but not bold fighter guy talk about airliners and an bold airline guy talk about fighters.
Thank you guys for the audience, it is time to go back lurking and spending my pension.
Last edited by RetiredF4; 4th Nov 2012 at 16:04.
Originally Posted by Retired F-4
After the AP disengagement until the initial pullup the UAS procedure would have been appropriate.
Originally Posted by Retired F-4
After the initial pullup we talk per definition about an upset situation. The upset started per Definition with SW1 and lasted until the end of the flight.
Originally Posted by Retired F4
By mistake or by what intention? To counter the deviation from assigned altitude, to correct the pitch, to arrest the climb? Or did he do it unintentionally, by chance, or because he forgot that he liked pulling?
Originally Posted by Retired F4
As they are already available (customer option, BUSS) and needn´t being newly developped, and as there is no known difficult training at the moment for those who bought that option i´d say:
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As discussed earlier, the BUSS is no solution for the conditions encountered by AF447. If installed, it can only be made available by switching off the three ADR's, which then remain unavailable for the remainder of the flight. Furthermore, it presents misleading information at altitudes higher than about FL250 because it uses a default stall warning threshold value that does not change with Mach, and (as I understand it) the high speed limit is Vmo but Mmo is not taken into account.
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Originally posted by Clandestino
Operator's Guide to Human Factors in Aviation, author unknown
Operator's Guide to Human Factors in Aviation, author unknown
Dr Hamish G. MacDougall BSc (Hons), PhD
See Conference Presentations / Peer Reviewed Papers
e.g. 107 "How the Brain Interprets Linear Acceleration During Flight." etc,
Originally posted by Clandestino
...cracked me up..... Makes me wonder at what operator was that presentation aimed.
...cracked me up..... Makes me wonder at what operator was that presentation aimed.
Last edited by rudderrudderrat; 5th Nov 2012 at 23:13.
Clandestino, you don't need to be ACM trained to understand, and apply (or be wary of) unloading aerodynamic surfaces, or an aircraft.
Please look up "mast bumping" as it concerns a Huey helicopter. I hope you will be able to reconcile the fact that my instructors, some 30 years ago, were able to convey successfully to me the necessity to NOT unload the head, with no reference whatsoever to EVM or ACM. Also the point of keeping the head loaded while doing NoE maneuvers in low level flying.
In simple, Level 2 English, Unloading the aircraft is done by reducing the G load, and loading the aircraft, as you can imagine, is normally achieved by increasing the G load. This is as true in a Cessna 172 as in a Pitts Special as in a Gulfstream as in Mistubishi Zero, or in a Huey or a Lynx.
For Old Carthusian: I believe Clandestino nailed the reason for the added pages: human factors.
Please look up "mast bumping" as it concerns a Huey helicopter. I hope you will be able to reconcile the fact that my instructors, some 30 years ago, were able to convey successfully to me the necessity to NOT unload the head, with no reference whatsoever to EVM or ACM. Also the point of keeping the head loaded while doing NoE maneuvers in low level flying.
In simple, Level 2 English, Unloading the aircraft is done by reducing the G load, and loading the aircraft, as you can imagine, is normally achieved by increasing the G load. This is as true in a Cessna 172 as in a Pitts Special as in a Gulfstream as in Mistubishi Zero, or in a Huey or a Lynx.
For Old Carthusian: I believe Clandestino nailed the reason for the added pages: human factors.
Last edited by Lonewolf_50; 5th Nov 2012 at 15:52.
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Somatogravic illusion ?
The TSB's Finding that the Transat captain PF experienced somatogravic illusion is somewhat questionable. In 1.11.4 Somatogravic Illusion, they write:
That is o.k., but doesn't describe what happened in the incident. The airplane attitude started to decrease at about 1440:32 EST, when the airspeed was actually decreasing. At about 1440:44 EST the airplane started to descend. Between about 1440:41 and 1440:48 the airspeed increased by about 33 kt IAS, 30 kt TAS in 7.3 seconds, an acceleration of 0.21 g. Yet their figure 10 shows a perceived attitude that is 35° greater than the real attitude, i.e. corresponding to an acceleration of 0.57 g. Difficult to understand.
(...) When the aircraft is accelerating, the sense organs of the inner ear of the pilot send a signal to the pilot’s brain that is interpreted as tilting backwards instead of accelerating forward. If the aircraft nose is simultaneously raised, the pilot has a very strong sensation of climbing. The illusion of false climb tends to lead the pilot to lower the nose and descend. The aircraft then accelerates and the illusion can intensify.
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Hi HN39,
I agree it doesn't match very well. Some of the graphs seem to have slipped by almost 5 seconds.
If we assume the graphs have not been superimposed correctly, and that the greatest illusion of pitch was caused during the fastest acceleration, then between 19:40:42 and 19:40:47 the speed increased from 200 to 240kts. i.e. 40 kts in 5 secs or 8kts per second (0.41g)
ArcTAN 0.41/1 = about +22 degs GIA
When the real pitch and perceived pitch matched at 13 degs (shown as 5 seconds before the start of the acceleration), then the Somatogravic illusion of + 22 degs would make the perceived attitude as 35 degs.
I agree it doesn't match very well. Some of the graphs seem to have slipped by almost 5 seconds.
If we assume the graphs have not been superimposed correctly, and that the greatest illusion of pitch was caused during the fastest acceleration, then between 19:40:42 and 19:40:47 the speed increased from 200 to 240kts. i.e. 40 kts in 5 secs or 8kts per second (0.41g)
ArcTAN 0.41/1 = about +22 degs GIA
When the real pitch and perceived pitch matched at 13 degs (shown as 5 seconds before the start of the acceleration), then the Somatogravic illusion of + 22 degs would make the perceived attitude as 35 degs.
Last edited by rudderrudderrat; 6th Nov 2012 at 15:27. Reason: spelling
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Hi rudderrudderrat,
The report states:
Appendix 1 states:
Time ......... IAS ..... pitch
19:40:40.9 ... 197.5 ... 8.5
19:40:44.1 ... 208.9 ... -2.3
19:40:48.3 ... 230.3 ... -2
19:40:52.1 ... 241.9 ... -0.06
The report states:
At about 1440:44, at the end of the climb, the perceived attitude reached greater than 30° whereas the actual attitude was about -3°.
Time ......... IAS ..... pitch
19:40:40.9 ... 197.5 ... 8.5
19:40:44.1 ... 208.9 ... -2.3
19:40:48.3 ... 230.3 ... -2
19:40:52.1 ... 241.9 ... -0.06
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Hi rudderrudderrat,
You may have noted that my purple line shows the perceived attitude according to Appendix 1.
EDIT::
But you don't question their opinion about the rôle of somatogravic illusion in this incident?
You may have noted that my purple line shows the perceived attitude according to Appendix 1.
EDIT::
I've been trying for ages to get the words and the picture to say the same
Last edited by HazelNuts39; 6th Nov 2012 at 16:37.
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Hi HN39,
The effect is very well documented, e.g. see http://www.faa.gov/library/manuals/a...apter%2001.pdf Page 1-6.
The Incident Investigators concluded the crew suffered somatogravic illusion. The crew survived and explained their reason's for their actions. I simply can't verify the same value, so why would I question their opinion?
But you don't question their opinion about the rôle of somatogravic illusion in this incident?
The Incident Investigators concluded the crew suffered somatogravic illusion. The crew survived and explained their reason's for their actions. I simply can't verify the same value, so why would I question their opinion?
When the aircraft is accelerating, the sense organs of the inner ear of the pilot send a signal to the pilot’s brain that is interpreted as tilting backwards instead of accelerating forward. If the aircraft nose is simultaneously raised, the pilot has a very strong sensation of climbing. The illusion of false climb tends to lead the pilot to lower the nose and descend. The aircraft then accelerates and the illusion can intensify.
from the peanut gallery
Good flamefest, but I liked Okie's observation and the input from our rotorhead Wolf.
Seems to this old and not so bold fighter type that 99% of everything ever capable of sustaining flight obeys the same rules, gliders included.
- It's damned hard to stay in a stall at zero gee.
- Zero gee reduces induced drag and allows your thrust to have an effect on your speed.
- Forget all the somatogravic illusion crapola. We were all trained and routinely flew IFR when our inner ear sensors and butt told us we were inverted or in a left turn or..... I would submit to this august body of experts that the fighter types had to overcome the physiological stuff more frequently than most of the heavy pilots.
- Jiminy Cricket can suggest that you lower the nose, but the other guy has to do so and not continue an unreasonable stick input. So crew coordination and a clear chain of command comes into play, ya think?
WRT to Okie's observation: I was priveleged to check out dozens of USAF Reserve and Guard pilots that had a day job flying heavies. Think Vipers and Sluf's. I had zero problems when they came outta that telephone booth wearing their cape and then we briefed and flew an ACM or ground attack mission. I always thot that they would be the ones I wanted to fly with seated back in row 26B when something bad happened. So salute to them.
WRT to Wolf's observation: Yep, those rotors are simply moving wings and behave just like the ones that don't move. Only biggie is unloading those suckers unless you were in one of those "rigid rotor" types we tested years ago.
Back to the peanut gallery...
Seems to this old and not so bold fighter type that 99% of everything ever capable of sustaining flight obeys the same rules, gliders included.
- It's damned hard to stay in a stall at zero gee.
- Zero gee reduces induced drag and allows your thrust to have an effect on your speed.
- Forget all the somatogravic illusion crapola. We were all trained and routinely flew IFR when our inner ear sensors and butt told us we were inverted or in a left turn or..... I would submit to this august body of experts that the fighter types had to overcome the physiological stuff more frequently than most of the heavy pilots.
- Jiminy Cricket can suggest that you lower the nose, but the other guy has to do so and not continue an unreasonable stick input. So crew coordination and a clear chain of command comes into play, ya think?
WRT to Okie's observation: I was priveleged to check out dozens of USAF Reserve and Guard pilots that had a day job flying heavies. Think Vipers and Sluf's. I had zero problems when they came outta that telephone booth wearing their cape and then we briefed and flew an ACM or ground attack mission. I always thot that they would be the ones I wanted to fly with seated back in row 26B when something bad happened. So salute to them.
WRT to Wolf's observation: Yep, those rotors are simply moving wings and behave just like the ones that don't move. Only biggie is unloading those suckers unless you were in one of those "rigid rotor" types we tested years ago.
Back to the peanut gallery...
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More about somatogravic illusion
In post #710 I ok'd following quote from a TSB incident report:
Thinking about it further, I felt I ought to correct that in the interest of an understanding of the flight mechanical aspects of the phenomenon.
Actually only the first sentence is entirely correct. The second sentence is sensorially correct during acceleration on the runway, although it is perhaps somewhat unlikely that it would cause a strong sensation of climbing in an experienced pilot. However, when the aircraft nose is raised in flight, the airplane will actually start climbing and the acceleration will reduce. The reduction of acceleration tilts the perceived attitude forward by the same amount as the real pitch change is nose-up. In other words, the somatogravic illusion is then that the pitch attitude has not changed. A similar argument applies in reverse when the nose is pitched down.
When the aircraft is accelerating, the sense organs of the inner ear of the pilot send a signal to the pilot’s brain that is interpreted as tilting backwards instead of accelerating forward. If the aircraft nose is simultaneously raised, the pilot has a very strong sensation of climbing. The illusion of false climb tends to lead the pilot to lower the nose and descend. The aircraft then accelerates and the illusion can intensify.
Actually only the first sentence is entirely correct. The second sentence is sensorially correct during acceleration on the runway, although it is perhaps somewhat unlikely that it would cause a strong sensation of climbing in an experienced pilot. However, when the aircraft nose is raised in flight, the airplane will actually start climbing and the acceleration will reduce. The reduction of acceleration tilts the perceived attitude forward by the same amount as the real pitch change is nose-up. In other words, the somatogravic illusion is then that the pitch attitude has not changed. A similar argument applies in reverse when the nose is pitched down.
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Hi HazelNuts39
Quote..."The reduction of acceleration tilts the perceived attitude forward by the same amount as the real pitch change is nose-up. In other words, the somatogravic illusion is then that the pitch attitude HAS NOT CHANGED. A similar argument applies in reverse when the nose is pitched down."
caps mine......
Certainly that works as an explanation for a pilot to continue his NU input even though he is climbing, and decelerating? pilot has also foregone scan and has lost his binky, the Flight Director, so.......
Too easy?
Quote..."The reduction of acceleration tilts the perceived attitude forward by the same amount as the real pitch change is nose-up. In other words, the somatogravic illusion is then that the pitch attitude HAS NOT CHANGED. A similar argument applies in reverse when the nose is pitched down."
caps mine......
Certainly that works as an explanation for a pilot to continue his NU input even though he is climbing, and decelerating? pilot has also foregone scan and has lost his binky, the Flight Director, so.......
Too easy?