Somotogravic Illusion
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Somotogravic Illusion
The thread on the Roma C210 accident drifted a fair bit towards Somatagravic Illusion. We don't yet know if that was a factor so here is a thread to discuss it.
I experienced it years ago in a Baron departing into a desert black hole and think I only got out of it because I had a full IFR rating.
I think the NVFR rating is setting people up to become comfortable with departing at night towards a nearby town or with some other ground lighting reference so that one day when they depart into a black hole they have developed habits of not scanning instruments in a disciplined manner and are ill equipped to cope with the illusion.
Am I on my own with that opinion?
I experienced it years ago in a Baron departing into a desert black hole and think I only got out of it because I had a full IFR rating.
I think the NVFR rating is setting people up to become comfortable with departing at night towards a nearby town or with some other ground lighting reference so that one day when they depart into a black hole they have developed habits of not scanning instruments in a disciplined manner and are ill equipped to cope with the illusion.
Am I on my own with that opinion?
Yep I'm not a fan of NVFR. Did it the other day with a student in the blackest of blackness I've seen in a long time and ended up doing it via IFR procedures.
Apart from the leans which I get from time to time, the best illusion I've had is autokinetic landing in Cocos Islands in the dark. The only lights were the runway, the rest completely black. The runway started dancing around in the window and I couldn't control it. VERY disturbing !! Goes away once you get closer to landing.
Apart from the leans which I get from time to time, the best illusion I've had is autokinetic landing in Cocos Islands in the dark. The only lights were the runway, the rest completely black. The runway started dancing around in the window and I couldn't control it. VERY disturbing !! Goes away once you get closer to landing.
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Framer, you're not Robinson Crusoe there. Had it demonstrated to me departing Nowra rwy 21 during my NVFR training yonks ago. Very sobering. The flight line is well lit, all the Albatross infrastructure well lit, all to the E of the rwy. SW and W wass utterly black (isn't so much now).
Between somatogravic effect, poor scan, failure to trust working instruments, unanticipated IMC, fog and vertigo there are dangers galore for the complacent NVFR pilot.
Between somatogravic effect, poor scan, failure to trust working instruments, unanticipated IMC, fog and vertigo there are dangers galore for the complacent NVFR pilot.
'framer' I think any thread relating to an A/C crash will eventually stall (for want of a better word) until as such time as the real known cause (if ever) is revealed from the authorities as there's only so much you can say about a particular accident.Thread drifting is ripe on PPRuNe when the core subject can't be expanded on too much more.
Still it's probably not a bad idea to have a separate thread on this insidious illusion so that one can focus on this particular problem without getting into a slanging match as we often see on a lot of threads where the Mods in their ultimate wisdom lock it.
I often count the amount of locked threads on one particular page (sad life I know!) which at times amounts to around 7 or so at times!
I believe that this illusion/feeling SI can be handled & quite well "IF" we have proper training/education, adequate 'tools' as in A/C instrumentation & currency,the latter being very important as having an IFR rating for Eg or a NVFR (Class 4 old days) is good & well but pretty much useless unless yr current, hence IFR renewals which I might add are not often enuf for most out there.
Personally I did a Class 4 yonks ago (NVFR) & it taught me valuable lessons which I'd like to think was a good precursor to my IFR rating years latter.
Heavy metal drivers get checked very reg & for good reasons but small Comm & Pvt drivers are left to their own devices for the whole year until renewal, now that's scary!
Wmk2
Still it's probably not a bad idea to have a separate thread on this insidious illusion so that one can focus on this particular problem without getting into a slanging match as we often see on a lot of threads where the Mods in their ultimate wisdom lock it.
I often count the amount of locked threads on one particular page (sad life I know!) which at times amounts to around 7 or so at times!
I believe that this illusion/feeling SI can be handled & quite well "IF" we have proper training/education, adequate 'tools' as in A/C instrumentation & currency,the latter being very important as having an IFR rating for Eg or a NVFR (Class 4 old days) is good & well but pretty much useless unless yr current, hence IFR renewals which I might add are not often enuf for most out there.
Personally I did a Class 4 yonks ago (NVFR) & it taught me valuable lessons which I'd like to think was a good precursor to my IFR rating years latter.
Heavy metal drivers get checked very reg & for good reasons but small Comm & Pvt drivers are left to their own devices for the whole year until renewal, now that's scary!
Wmk2
Last edited by Wally Mk2; 31st Mar 2013 at 01:47.
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I don't think that a NVFR rating on it's own does set people up for disaster. Perhaps I was fortunate to have gained mine in the bush, where the black hole trap was well known and discussed. Certainly, the instrument scan and arranging things (take off directions etc) to minimize the trap were big parts of the training. There's no doubt, though, that the first time SI happens it's a big shock, and every ounce of discipline is needed to shake it. Mine was in an old Mooney on climbout on a pitch black night at Condobolin. Began to think the gyros has toppled and the wing leveller was malfunctioning but rationality took over - I knew enough to realize it was me and not the aircraft. LSALT in the area is pretty low and I was able to reach it easily, but even establishing a moderate rate of climb was difficult - it felt like the aircraft was extremely nose high. Once at altitude and properly established on track, the whole picture snapped back into place in an instant. I can't honestly say I'd come close to the same experience during training, but it was certainly the training and the fluency with the instrument climbout etc that was essential. I could also imagine that if a pilot did a NVFR rating on the populated seaboard, with all the lights and other cues, it might be very hard to realize what you can be up against west of the ranges. So, maybe the lesson is that there's no substitute for rigorous training, regularly renewed (including operations at isolated strips).
I'm currently researching SI as a factor in aircraft accidents and will publish soon. What I have found is that it is more common than people think and sometimes missed by accident investigators, and it is nearly always fatal to all those on board so witness reports are few. Also,it cannot be trained for in an aircraft - it has to be briefed. And the level of knowledge in the industry is poor, especially with pilots.
I have been asking my fellow pilots about SI and some have. Ever heard of it, the ones who have been through training recently can remember it from their human factors course.
I work in the safety office of a largish airline and of the for pilots working there, two of us have experienced it. Both taking off from an airfield on the coast at night. In my case, I was thoroughly briefed to expect it, as it during training and was a known problem with this runway as at least two aircraft had flown into the sea at night in the past. It was a very strong illusion and it took all my powers of concentration to stay fixed on the AI and hold my attitude. The other pilot noticed a large white thing just below the aircraft. At first he thought it was cloud but rapidly realised it was a breaking wave and he was at about 30' and still descending. A very lucky escape!
I have found about 40 accidents where SI was cited as a cause from the last 30 years. As it's not always recognised, I'm sure the true accident rate is probably in excess of double that. And in those statistics, there are three airliners in the last ten years - the most recent being the Affriquiyah A330 at Tripoli in 2010. All three were during go arounds at night.
As for prevention, the only solution is to make pilots aware of it and emphasise the correct techniques in training. As far as I know, the recent notice from CASA as a result of the C210 crash is the only warning published by an aviation authority. Well done CASA.
I have been asking my fellow pilots about SI and some have. Ever heard of it, the ones who have been through training recently can remember it from their human factors course.
I work in the safety office of a largish airline and of the for pilots working there, two of us have experienced it. Both taking off from an airfield on the coast at night. In my case, I was thoroughly briefed to expect it, as it during training and was a known problem with this runway as at least two aircraft had flown into the sea at night in the past. It was a very strong illusion and it took all my powers of concentration to stay fixed on the AI and hold my attitude. The other pilot noticed a large white thing just below the aircraft. At first he thought it was cloud but rapidly realised it was a breaking wave and he was at about 30' and still descending. A very lucky escape!
I have found about 40 accidents where SI was cited as a cause from the last 30 years. As it's not always recognised, I'm sure the true accident rate is probably in excess of double that. And in those statistics, there are three airliners in the last ten years - the most recent being the Affriquiyah A330 at Tripoli in 2010. All three were during go arounds at night.
As for prevention, the only solution is to make pilots aware of it and emphasise the correct techniques in training. As far as I know, the recent notice from CASA as a result of the C210 crash is the only warning published by an aviation authority. Well done CASA.
Dan
I don't understand how you can say it can be briefed and not trained for and would be interested in further discussion. In my experience, no amount of briefing would prepare you for the sensation. I've probably had 3 instances.
The first and most severe was with an instructor doing my NVMC rating (ironically).Doing a missed approach heading South from Cowes on a moonless night over the sea.
The second was really weird and I'm not sure fits the theory. Heading North from Port Augusta as the sun set on a clear night. On my left was a bright, brilliant outback sunset and on my right was pitch black.
The the was landing at night at Woomera. The lights from the township are not visible at the airport. Once again a moonless night so that there was no horizon. The ground was the same colour as the sky and the runway was not distinguishable from its surrounds. The only visible thing was the runway lighting which seemed to float in a surreal way in a sea of black.
I would say that no amount of briefing prepares you for this and my initial experience of becoming vertiginous with an instructor was invaluable. The level discipline of limiting your world to just the instruments in front of you is greater than required in IMC.
I don't know what airline level SIMS are like, but my expectation would be that the vibration, yaw, roll, pitch and noise of a real aeroplane are important antecedents in provoking disorientation. So, I would vote for it being part of training in a real aircraft.
I don't understand how you can say it can be briefed and not trained for and would be interested in further discussion. In my experience, no amount of briefing would prepare you for the sensation. I've probably had 3 instances.
The first and most severe was with an instructor doing my NVMC rating (ironically).Doing a missed approach heading South from Cowes on a moonless night over the sea.
The second was really weird and I'm not sure fits the theory. Heading North from Port Augusta as the sun set on a clear night. On my left was a bright, brilliant outback sunset and on my right was pitch black.
The the was landing at night at Woomera. The lights from the township are not visible at the airport. Once again a moonless night so that there was no horizon. The ground was the same colour as the sky and the runway was not distinguishable from its surrounds. The only visible thing was the runway lighting which seemed to float in a surreal way in a sea of black.
I would say that no amount of briefing prepares you for this and my initial experience of becoming vertiginous with an instructor was invaluable. The level discipline of limiting your world to just the instruments in front of you is greater than required in IMC.
I don't know what airline level SIMS are like, but my expectation would be that the vibration, yaw, roll, pitch and noise of a real aeroplane are important antecedents in provoking disorientation. So, I would vote for it being part of training in a real aircraft.
The way I was taught to take off at night regardless of what is outside, is to stay 100% on instruments until 500ft and mostly on instruments on xwind.. I have experienced illusions , but trust in the instruments makes it go away after a minute or so.. Very confusing if not prepared or taught well..
The NVFR in my opinion is a nice bridge between vfr and IFR as long as its taught carefully and treated with the respect it deserves....
The NVFR in my opinion is a nice bridge between vfr and IFR as long as its taught carefully and treated with the respect it deserves....
Nunc est bibendum
One of the worst cases of the leans I've ever had was departing LAX towards the east and then turning right. As we passed over the coast in a right turn I had lights out the right but they were not the lights of a city but rather the lights along a coast line. Had me convinced I was about 80 degree angle of bank and very, very nose high. Of course, an autopilot engage button is closely available for these sorts of situations when flying a heavy- and some would say that I had no business hand flying a clean up of a heavy aeroplane at night in busy airspace but that's an argument for another day- but it's handy every now and then to experience these sorts of things and to remind yourself how important the dials actually are.
Sorry, less about somtagravic illusion and more about core IF skills. I don't know that anyone will ever get somotagravic in a 744 or A380. More likely in a 767, 777 or 737.
Sorry, less about somtagravic illusion and more about core IF skills. I don't know that anyone will ever get somotagravic in a 744 or A380. More likely in a 767, 777 or 737.
'keg' that's a good comment re "some would say I had no business hand flying a clean up of a heavy aeroplane at night in busy airspace". Even though at first I thought this comment when I first heard it in & around the Sim was unwarranted because we are pilots we are trained & very clever (
)but I now believe that the use of high automation appropriate to the situation as you describe above should be used. The Autoflight system in modern A/c can fly far more accurately than we mere mortal beings especially when we are tired & I am not to proud to say hey let 'George' do the work they don't pay me enuf to hand fly it under those circumstances, unless of course it's absolutely necessary then the situation can be managed a different way to reduce the human workload at the time.
I've been a little disorientated after T/off at night in the 'bus' say during a turn & seeing light patterns I wasn't expecting but I wasn't driving the contraption:-)
I often fly the 'bus' to clean up when in good visual conditions for practice but that's it as I don't wanna visit the CP for tea & bickies
Wmk2
)but I now believe that the use of high automation appropriate to the situation as you describe above should be used. The Autoflight system in modern A/c can fly far more accurately than we mere mortal beings especially when we are tired & I am not to proud to say hey let 'George' do the work they don't pay me enuf to hand fly it under those circumstances, unless of course it's absolutely necessary then the situation can be managed a different way to reduce the human workload at the time.I've been a little disorientated after T/off at night in the 'bus' say during a turn & seeing light patterns I wasn't expecting but I wasn't driving the contraption:-)
I often fly the 'bus' to clean up when in good visual conditions for practice but that's it as I don't wanna visit the CP for tea & bickies
Wmk2
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If you're under the impression experience or training will prevent illusions, you're delusional (no malice, just liked the pun). Illusions are physiological, no amount of experience will prevent you from feeling their effects. Training and experience will equip you to overcome the sensations and maintain control in the face of 85 million years of evolution but not to eliminate them completely.
You have to keep in mind what's happening: during a night departure, out of your 6 senses, taste and smell ain't helping you, so they're out. You're seated, so forget touch and your general spacial-touch orientation; your vestibular system is all over the place (you're moving in 3 different planes but seated, lets face it, this is more than confusing to your "primitive" sensory system). Your sight, well whats it seeing? An AH is representative of the outside world but that's not what you're sight is picking up, it just sees the black. And sound, well the noise of the aircraft is enough to disorientate you alone.
More than a bit of experience in the Aus outback, single pilot in turbines has shown me that illusions are plentiful and especially back of the clock. The sole reference circling approach, distant light reflecting off of cloud or flying above cloud illuminated from underneath giving false horizons, black hole approach, departing into black abyss; the illusions don't stop, just how well you adapt to ignoring them.
Personally, having trained a few NVFR's, I'm a firm believer that the NVFR should only be used for its intention as a back up on a long day. Outback night is as good as IF, the fact you're not in cloud is irrelevant, you still have sole reference to the instruments and I don't believe NVFR prepares you well enough for this. As old akro said, Night VMC instrument flying can be harder than IMC IF. Thank god for AFCS
You have to keep in mind what's happening: during a night departure, out of your 6 senses, taste and smell ain't helping you, so they're out. You're seated, so forget touch and your general spacial-touch orientation; your vestibular system is all over the place (you're moving in 3 different planes but seated, lets face it, this is more than confusing to your "primitive" sensory system). Your sight, well whats it seeing? An AH is representative of the outside world but that's not what you're sight is picking up, it just sees the black. And sound, well the noise of the aircraft is enough to disorientate you alone.
More than a bit of experience in the Aus outback, single pilot in turbines has shown me that illusions are plentiful and especially back of the clock. The sole reference circling approach, distant light reflecting off of cloud or flying above cloud illuminated from underneath giving false horizons, black hole approach, departing into black abyss; the illusions don't stop, just how well you adapt to ignoring them.
Personally, having trained a few NVFR's, I'm a firm believer that the NVFR should only be used for its intention as a back up on a long day. Outback night is as good as IF, the fact you're not in cloud is irrelevant, you still have sole reference to the instruments and I don't believe NVFR prepares you well enough for this. As old akro said, Night VMC instrument flying can be harder than IMC IF. Thank god for AFCS
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Posters to this thread are using the abbreviation SI.
Please don't, as it could mean Somatogravic Illusion,
or the more broad term Sensory Illusion.
It gets confusing if you abbreviate thus.
As to Somatogravic illusion, the naval catapult aviators should have the most experience.
There is a simulator for Somatogravic illusion, and it is very very persuasive (at least I thought so - 3 out of 3 immediate crashes even though I knew it was coming.
RAAF Aviation medicine have one.
Please don't, as it could mean Somatogravic Illusion,
or the more broad term Sensory Illusion.
It gets confusing if you abbreviate thus.
As to Somatogravic illusion, the naval catapult aviators should have the most experience.
There is a simulator for Somatogravic illusion, and it is very very persuasive (at least I thought so - 3 out of 3 immediate crashes even though I knew it was coming.
RAAF Aviation medicine have one.
Last edited by rjtjrt; 31st Mar 2013 at 05:10.
When you live....
I don't understand how you can say it can be briefed and not trained for and would be interested in further discussion. In my experience, no amount of briefing would prepare you for the sensation
I definitely learned on a night flight from TW - GLI. Quite an overcast night but technically NVFR. Departed off RWY 30 at TW and circled up to the LSALT of 6400. I had definitely felt a little 'off balance' during the rotation and left hand circling climb but flew the instruments and mostly ignored the lights on the ground that popped in and out of view as we went around and around.
Tracking to GLI, after setting power etc, I relaxed back a bit and settled into the short easy cruise.
In my field of view there was one bright star about 30 degrees off the right nose about 45 degrees 'up' and one farm house light about 45 degrees 'down' off the left wing.
Despite the instruments, there was nothing I could do to shake the feeling that I was in a 30-40 degree left bank and about 20 degrees nose down.
Engaged the autopilot and closed my eyes for a second, when I looked back up 'normality' had resumed.
It certainly taught me that despite practice, training and experience, the inner ear is a powerful thing!
Tracking to GLI, after setting power etc, I relaxed back a bit and settled into the short easy cruise.
In my field of view there was one bright star about 30 degrees off the right nose about 45 degrees 'up' and one farm house light about 45 degrees 'down' off the left wing.
Despite the instruments, there was nothing I could do to shake the feeling that I was in a 30-40 degree left bank and about 20 degrees nose down.
Engaged the autopilot and closed my eyes for a second, when I looked back up 'normality' had resumed.
It certainly taught me that despite practice, training and experience, the inner ear is a powerful thing!
The Autoflight system in modern A/c can fly far more accurately than we mere mortal beings ...
... the autopilot isn't subject to the same errors, illusions and distractions as I am (it has it's own errors) - but it isn't more accurate.
Last edited by Checkboard; 31st Mar 2013 at 09:52.
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The question is really why are pilots experiencing SI? NVFR is only dangerous through poor discipline in the scan. I don't know how many times I've had to say to students 'eyes inside' during turns in the circuit with the benefit of the city lights close by.i guarantee when I send em solo they're gazing at the pretty lights.
More talking about the leans there but if they're not scanning instruments during turns why would they in the climbout.
Is NVFR any more dangerous than IFR at night? I'm not considering the twin/single argument, it's an illusion thread after all.
More talking about the leans there but if they're not scanning instruments during turns why would they in the climbout.
Is NVFR any more dangerous than IFR at night? I'm not considering the twin/single argument, it's an illusion thread after all.
To be honest I don't think the 5 hours in the circuit at night for the IF rating prepares you for much at all, considering the privileges it grants. NVFR training out west of the ranges was a very good learning experience.
In the 1980s we used to fly single pilot IFR /IMC offshore in the North Sea to rigs and platforms regularly at night in S-76 which had stabilisation but no autopilot, heading or height hold.
Landing on small unmanned platforms at night could be tricky as they had no Derrick, just a helideck. It appeared to float in space and called for one to fly a disciplined set of height /speed range "gates" on each approach.
Taking off into blackness called for power application, 5 degrees nose down, positive ROC to Vtoss, then it was just back to IFR flying as usual.
Those transitions from instrument to visual and back were always interesting. I must have done it hundreds of times by myself. Needless to say, my hand IF skills were honed in those days!
Luckily, before being released single pilot, we had excellent quality line training. To this day, I believe line training to be the most important part of aviation but its sadly often overlooked.
Landing on small unmanned platforms at night could be tricky as they had no Derrick, just a helideck. It appeared to float in space and called for one to fly a disciplined set of height /speed range "gates" on each approach.
Taking off into blackness called for power application, 5 degrees nose down, positive ROC to Vtoss, then it was just back to IFR flying as usual.
Those transitions from instrument to visual and back were always interesting. I must have done it hundreds of times by myself. Needless to say, my hand IF skills were honed in those days!
Luckily, before being released single pilot, we had excellent quality line training. To this day, I believe line training to be the most important part of aviation but its sadly often overlooked.
Last edited by industry insider; 31st Mar 2013 at 14:13.
''I think Dan is trying to say that you can't generate the leans or SI in a training environment but have to rely on been briefed that such things exist''
Precisely. You can only be warned about it and given training to minimise the illusion should it happen to you. The somatogravic illusion is impossible to simulate. Try and do it in the air having told the student he's going to experience it - he won't as he's alert to the issue. And you can't replicate it in a simulator as to simulate acceleration the sim will pitch the subject up - using the illusion itelf to simulate the acceleration. It's nearly impossible to train for.
''There is a simulator for Somatogravic illusion, and it is very very persuasive (at least I thought so - 3 out of 3 immediate crashes even though I knew it was coming. RAAF Aviation medicine have one.''
You sure? It maybe a simulator for one of the other spatial disorientaion phenomena. It's probably the same as one of the gadgets tha RAF has - of which I'm quite familiar. The somatogravic illusion is not possible to replicate unless you can acheive prolonged linear acceleration. The US Navy have done several atudies into it and can only achieve that by using a centrifuge - and there are not many of those around.
I have seen it done in the centrifuge at Farnborough when I did some anti g training. While we were there they gave us the opportunity to try the somatogravic illusion. We put on a blindfold and were told to attempt to 'stay level' using a sidestick while the centriguge spun up. We all pitched forward, but at the time it felt as if it could have been a result of the application of g.
Of the accidents I have researched, it's clear that the illusion is no respector of experience (from 495 to 27,000 hrs), can happen to any type (Pa28 to A330 with a MiG21 and helicopters thrown in), and is nearly always fatal (about 85% of everyone on board). But the highest statistic group (apart from carrier catapault launches) seems to be light twins.
Precisely. You can only be warned about it and given training to minimise the illusion should it happen to you. The somatogravic illusion is impossible to simulate. Try and do it in the air having told the student he's going to experience it - he won't as he's alert to the issue. And you can't replicate it in a simulator as to simulate acceleration the sim will pitch the subject up - using the illusion itelf to simulate the acceleration. It's nearly impossible to train for.
''There is a simulator for Somatogravic illusion, and it is very very persuasive (at least I thought so - 3 out of 3 immediate crashes even though I knew it was coming. RAAF Aviation medicine have one.''
You sure? It maybe a simulator for one of the other spatial disorientaion phenomena. It's probably the same as one of the gadgets tha RAF has - of which I'm quite familiar. The somatogravic illusion is not possible to replicate unless you can acheive prolonged linear acceleration. The US Navy have done several atudies into it and can only achieve that by using a centrifuge - and there are not many of those around.
I have seen it done in the centrifuge at Farnborough when I did some anti g training. While we were there they gave us the opportunity to try the somatogravic illusion. We put on a blindfold and were told to attempt to 'stay level' using a sidestick while the centriguge spun up. We all pitched forward, but at the time it felt as if it could have been a result of the application of g.
Of the accidents I have researched, it's clear that the illusion is no respector of experience (from 495 to 27,000 hrs), can happen to any type (Pa28 to A330 with a MiG21 and helicopters thrown in), and is nearly always fatal (about 85% of everyone on board). But the highest statistic group (apart from carrier catapault launches) seems to be light twins.
I don't understand how you can say it can be briefed and not trained for and would be interested in further discussion. In my experience, no amount of briefing would prepare you for the sensation
The following comments are not a typical young buck's war story (a show-off pilot known as a warrie, warie or warree or however you wish to spell it) - but a point of fact. But if ever one was going to have a serious example of somatogravic Illusion it would have been my first night take off at Williamtown NSW in a Mustang.
The combination of inexperience (230 hours total time) and with a closed canopy take off, landing light reflection off the back of the propeller and of course the startling acceleration. With the tail down, only one or two runway lights could be seen and when the stick was eased forward to get the tail up one had to watch the swing caused by torque and gyroscopic effect . Then lift off into total darkness and look down and reach down to get the gear handle up - all that in combination should have led to the illusional problem we are talking about.
But it simply didn't happen. Despite years of flying at night out of black hole Pacific atolls, I can say quite honestly it has never happened to me.
Yet there is ample evidence pilots have struck the problem. Some have lost their lives apparently to its effect while others coped.
I wonder therefore, if some pilots for some unknown physiogical reason, simply are not susceptable to somatogravic illusion on take off, while clearly other pilots are - even though flying the same type of aircraft.
Fast jet fighters are catapulted at enormous acceleration from aircraft carriers at night in total blackness. We don't know the statistics of crashes of these aircraft of course, but it seems that 99.9999% get away with it without crashing into the sea soon after lift off. If ever somatogravic illusion is waiting to catch the unwary or even those prepared for it, carrier take off's would be prime examples.
Does IMC currency help in any way? Maybe - but where is the proof? In my own case, as a 21 year old flying the Mustang at night, I certainly wasn't an experienced IMC or night flying pilot. After all, I had only recently graduated from Pilots course a few weeks earlier where we were taught instrument flying on Tiger Moths (now that was really limited panel) and Wirraways.
Perhaps then, experiencing somatogravic illusion on take off is a matter of individual physiological susceptibility, rather than it happens to every pilot when the right circumstances exist at the time.
It must be different to the physical sensation of "the leans" which is not as potentially dangerous, since most times the leans doesn't seem happen shortly after lift off, but at other times during turning or acceleration/deceleration/ sloping cloud deck.
Last edited by Centaurus; 1st Apr 2013 at 08:29.