Another one from B's channel...

[elaw]

https://youtu.be/WDwognXbUPE

[3WE]

This dude was at altitude…with what I ass-ume was a fancy Otto Pilot and a decent, low-silicon, broad-function FMS.

[ocelot]

I'm not sure I'll ever fully understand these spatial disorientation problems. It's one thing if you tumble your artificial horizon, or it's bust, but absent that... do people forget to look at it? Not believe it? Do people ...also not believe the horizon out the window? (Or maybe, in a sim the window is just a larger AH, so one gets used to the idea? I will just flip from one to the other as conditions warrant.)

Consequently I'm sort of inclined to suspect an autopilot disconnect from turbulence followed by lack of currency in hand-flying on instruments, maybe combined with unreliable airspeed and/or task saturation.

[3WE]

I'm not sure I'll ever fully understand these spatial disorientation problems.

When riding a J-31 in widespread IMC, when Flyover was busy, I suddenly noted our heading was ~180 degrees off…how in the hell did that happen? (We were holding, and I never felt a bank nor turn.)

During my brief IMC training, I never experienced disorientation. I did note that my bio sensations were my primary instrument, with the mechanical instruments fine tuning AND keeping me calibrated…

I can imagine someone getting strongly linked to their body AND IF YOU LOSE YOUR CALIBRATION, I can imagine one struggling to get it back.

Our flyboy says he’s never felt a second of disorientation…

I think there’s folks that get disorientated, and those that don’t…I don’t understand it either.

[Gabriel]

I'm not sure I'll ever fully understand these spatial disorientation problems. It's one thing if you tumble your artificial horizon, or it's bust, but absent that... do people forget to look at it? Not believe it? Do people ...also not believe the horizon out the window?

It's not a matter of believe. It is more a matter of how our brain is wired and how our senses are interconnected. It is not a mater of intellectual effort (well, that is part, bit not enough and in general it cannot be sustained) but practice so your brain gets wired to that environment. Our sense of equilibrium and orientation depends on 3 factors: Direction of the apparent gravity vector (sensed by all the body as weight). Change in angular speed in all 3 axes (sensed by the semi-circular canals in our inner ears). And visual reference. And they all work together. If you make may spins standing on the floor, it will be very difficult to walk straight immediately after (due to the vertigo sensation). If you want to aim for the door and you see that the door is over there, why do you miss it? You don't believe that the door is where you see it? Why do you tumble? You don't believe that down is where your weight sensation correctly is telling is down? No, it is because your brain cannot make sense of what your eyes see, what your whole body feels and what your inner ears tell. The "internal gyroscope" of the inner ear is very powerful in its signal but not very reliable. It accumulates errors quickly. But it has a constant "reset to horizontal" done by the sight, and the peripheral vision plays a huge role (the effect of a slanted horizon created by terrain or clouds is very well known and very powerful even when you KNOW it is slanted). So having a big horizon visible through the windshield and side windows can cope very well with keeping the inner ears calibrated. When you replace that with a 3-in artificial horizon that you brain treats more like an instrument than an horizon, and that you brain cannot pick its indication using peripheral vision when you are not looking directly at it, the calibration doesn't work so well at all so when you are inadvertently in a 30 bank turn, but your body feels vertical because in a coordinated turn there is no tilt sensation (the water in the glass stays parallel to the wings), your ears never detected the very slow bank rate, but your eyes see the little horizon titled, your brain stats to struggle. When you now correct the bank with a smooth but perceivable bank rate, now your eyes see the horizon horizontal but your ears are telling you that you are banked to the other side, and you brain gets even more confused. Yes, the door is there. Good luck walking straight to it. New big screens are a major improvement, since 1) they are big and let the brain relate it better with the real horizon, 2) It can still bi picked to some extent with peripheral vision, and 3) You don't need to look away from it to figure out speed, altitude vertical speed, heading, and nav since it is all presented inside of the synthetic horizon screen.

[elaw]

An update: https://youtu.be/6-E6cUXL0K8

[J]

An audio recording from a security camera near the crash site captured the sound of the plane as it rapidly descended. Pretty Chilling. Starts about 3:30.

[ocelot]

I'm not sure I'll ever fully understand these spatial disorientation problems. It's one thing if you tumble your artificial horizon, or it's bust, but absent that... do people forget to look at it? Not believe it? Do people ...also not believe the horizon out the window?

It's not a matter of believe. It is more a matter of how our brain is wired and how our senses are interconnected. It is not a mater of intellectual effort (well, that is part, bit not enough and in general it cannot be sustained) but practice so your brain gets wired to that environment.

Yes and no -- "believe" is shorthand for "use the AH as a reference for the outside". When people are or aren't getting motion sickness, even a small view to the outside to anchor their perceptions makes a large difference. (Or so people say; not much experience with it as I'm apparently not that susceptible, though I've also never been at sea in a storm either.) It seems reasonable to expect even a widget the size of an AH to be fairly effective too, especially if you're telling yourself "that's the outside horizon". (And if you're getting bounced around, or applying control inputs, it will move the way the outside horizon would and that improves the perception.)

So basically what I'm asking is: are people not looking at it and telling themselves "that's the outside horizon", or are they trying but it's not working for them? Or is the real problem that when they reach this kind of state they are also in an upset situation and consequently they're in a regime where they have no significant experience with the relationship between what their ear is feeling and what's happening to the plane?

I suppose the latter's probably a big part of it. More UPRT for everyone...

If you make may spins standing on the floor, it will be very difficult to walk straight immediately after (due to the vertigo sensation). If you want to aim for the door and you see that the door is over there, why do you miss it? You don't believe that the door is where you see it? Why do you tumble? You don't believe that down is where your weight sensation correctly is telling is down? No, it is because your brain cannot make sense of what your eyes see, what your whole body feels and what your inner ears tell.

Sure, but in that case it's because you stirred up the fluid in the semicircular canals and it's still moving around, which is not the case when flying. (Except maybe in a really severe upset, or a fully established spin, I guess; but those aren't the situations we're talking about.)

[ocelot]

Also, I'm quite familiar with the slightly odd feeling you get when the A/C (or a car, for that matter) does not do that little jerk that means you're fully stopped, and I imagine an unintended bank that snuck up on you is much the same, but for me at least the weird feeling is easily consciously overridden.

[3WE]

***I'm apparently not that susceptible***

***So basically what I'm asking is: are people not looking at it and telling themselves "that's the outside horizon", or are they trying but it's not working for them?***

My theory is that there’s two kinds of people: Susceptible and not_suscepible (yes, that’s an oversimplification, as trained and competent and etc. are variables) (moderate repetition below). I think you and flyboy, perhaps, are “immune” from the feelings and struggle to comprehend disorientation. I don’t know where I fall.

I have very little relevant experience: When I had about 10 hours of time on instruments and we had an actual IMC encounter, I was not stressed with keeping upright. Precise heading and altitude sucked, but up oily side down was easy. Much of my other instrument training included a sun-shadow attitude indicator. I also found that controlling the plane with a ‘failed’ AI and DG wasn’t super challenging.

A couple of times, I struggled with the AI vs Turn coordinator (they go opposite directions.- I like the turn thing as my brain envisions THE AIRPLANE…not the horizon as much…but i quickly recovered from the brain inversion.

When I look at YouTubes of AIs- they show very little “fine movement”. This is why I THINK the ears and buttocks are the brains primarily indicator- with the airplane instruments being somewhat gross, but very important, calibrators.

There was the 180 I missed in the Jetstream, once a bus I was on gently pulled forward and my brain mildly freaked as I “saw” the adjacent bus back up.

One time with snow covered windows, I backed up in the driveway and was shocked at how much braking I needed.

So I have been disoriented, but never really challenged in the roll axis.

My assumption is that guys lose sight of the instruments and can’t out smart their brain’s internal insistence on which way is up. Supposedly grabbing the approach plate out of the back seat of the 172 (a good head turn) is a great way to get out of whack. Never tried that in actual clouds)

[Gabriel]

My only experience in actual IMC behind the wheel was when I was doing instrument training under the hood and got into an actual cloud. I was able to focus on the artificial horizon and keep it upright, on speed, on altitude, on heading, VOR nailed, all nailed, ... for the several seconds it lasted... and while fighting myself to believe the instrument rather than my sensory inputs that were strongly trying to convince me that the actual situation was something else. If it had lasted longer and I had been setting altimeters, punching keys in the GPS, changing frequencies, ar taking notes of a clearance, let alone turning back to grab a chart or looking up to configure something in the overhead panel that doesn't exist in the Tomahawk, it would have been much harder. So I guess I am the susceptible type. On the other hand, I want to think that if I had much more exposure and training, my brain would learn to deal with the new set of sensory inputs.

One thing that did call my attention was how many cues we get from the environment without even realizing it. The hood was supposed to be blocking all of my outside view already. And I am not even sure what it was. Maybe I was able to get some indistinguishable blurry piece of horizon with the corner of my eye with my way-peroferal vision. Perhaps it was some way to figure out where the light was coming from, what parts of the inside of the cabin were brighter than others, some shadows, some glare, I don't know. But when I went into the cloud it was like a getting a BSOD. I took the hood off (in fact, flipped it up) and the sky looked all the same shade of white, the light seem to be coming from all places with the same intensity at the same time, there were no distinguishable shadows or glares inside of the cockpit, and I was definitively confused and just managing to force myself to believe the instruments. I was not aware that I was getting so much indirect information of the outside world that made keeping myself oriented much more easy when under the hood than in actual IMC.

I never had the chance to experience actual IMC again. But I did quite a few hours of enclosed FTD (with 3DOF motion but without video) and it felt somehow the same, at least from the visual cues (or lack thereof). I was quite disoriented the first times but eventually I got used to it and fully functional. Would that translate to real IMC? I don't know.

[elaw]

I can say I've never flown in IMC but to a degree I think that's only due to a loophole.

I did my first night cross-country flight in Florida from F45 to KAPF, pretty much straight both directions. That route goes over some large expanses of the Everglades that have a whole lot of nothing in them, it was completely dark out for most of the trip, and there was no moon. On the return trip about 10 minutes after we'd left civilization (and I use that term loosely in respect to FL) I realized it was "awfully dark out here". I freaked out slightly for a moment, then realized I'd been flying in those conditions already for 10 minutes so I should just keep doing what I was doing, and everything obviously worked out okay. But I have to say the lack of external visual references was damn close to what I think one would encounter in cloud. Of course there was one advantage other pilots would not have - I had my instructor in the right seat. Who I think was at least somewhat paying attention to my flying, in between going on and on about how good the rib dinner we just had was (the praise was well deserved).

Edit: I realized the "loophole" thing above may be a little unclear: I think there are some countries that do not allow night VFR... right?

[Gabriel]

I can say I've never flown in IMC but to a degree I think that's only due to a loophole.

I did my first night cross-country flight in Florida from F45 to KAPF, pretty much straight both directions. That route goes over some large expanses of the Everglades that have a whole lot of nothing in them, it was completely dark out for most of the trip, and there was no moon. On the return trip about 10 minutes after we'd left civilization (and I use that term loosely in respect to FL) I realized it was "awfully dark out here". I freaked out slightly for a moment, then realized I'd been flying in those conditions already for 10 minutes so I should just keep doing what I was doing, and everything obviously worked out okay. But I have to say the lack of external visual references was damn close to what I think one would encounter in cloud. Of course there was one advantage other pilots would not have - I had my instructor in the right seat. Who I think was at least somewhat paying attention to my flying, in between going on and on about how good the rib dinner we just had was (the praise was well deserved).

Edit: I realized the "loophole" thing above may be a little unclear: I think there are some countries that do not allow night VFR... right?

In Argentina night flight can be VFR only in the ATZ*. There is also no such thing as "VFR on top" or "VFR between layers" (VFR requires, among other things, 4/8 of visual contact with the ground at all times).
At least back then in my times.

* From the 3BS Unabridged Acronym Dictionary, ATZ, Aerodrome Traffic Zone, an airspace which nominally is a 2000ft-thick cake with a 2.5 NM radius centered in the middle of the longest runway, which basically means night flight can be VFR only "in the pattern".

[3WE]

***In Argentina night flight can be VFR only in the ATZ*. There is also no such thing as "VFR on top" or "VFR between layers" (VFR requires, among other things, 4/8 of visual contact with the ground at all times).***

Y'all are weenies...We are REQUIRED to do a night VFR flight as part of a normal PPL curriculum.

And next you'll tell me that you can't be cleared to land unless the runway really is clear for landing...(Yes, I know, we have beaten that one to death, already).

...but given statistics, there's a PART of me that would like to ban any license or flying that does not include some basic instrument competency, including actual IMC flight without an autopilot including reaching to the back to get a huge book of approach plates and looking up an approach at an unplanned airport...

...that and some sort of smartphone-based traffic avoidance system...sorry Bobby...

And, I'm not opposed to synthetic vision displays...and magenta lines...but not so much mindless rote procedure...except for verbally annunciating the lever when you grab it, and a statement that the desired result is indicated (3 green, or flaps X)

[Gabriel]

...but given statistics, there's a PART of me that would like to ban any license or flying that does not include some basic instrument competency, including actual IMC flight without an autopilot including reaching to the back to get a huge book of approach plates and looking up an approach at an unplanned airport...

While I sympathize with the idea, that is not some basic in instrument competency. And then what do you do with that "knowledge"? Will people feel encouraged to take additional risks of, let's not say going IMC intentionally, but flying in worse weather and finding themselves accidentally IMC in VFR? Or will this be helpful if the skill is not used in 5 years, when you find yourself in a situation that requires it? Remember, a lot of IMC upsets happen to instrument-rated pilots flying legally IFR on IMC.

[3WE]

2. ***Will people feel encouraged to take additional risks of, let's not say going IMC intentionally, but flying in worse weather and finding themselves accidentally IMC in VFR?***

3. ***Remember, a lot of IMC upsets happen to instrument-rated pilots flying legally IFR on IMC 4. such as the accident in this very thread..***

1. I was being a little bit facetious- can we really regulate everything?

2. Yes. I tend to focus on the non-instrument pilot who encounters “worse than forecast” and knows very little…the whole world of light aviation is trade offs. (One vs two engines)

3. All that being said, draw a Venn diagram…those who know the methods, those that don’t know the methods, those prone to disorientation, those not, those that inadvertently encounter “worse than forecast weather”…I do not like the intersection of those with minimal training and inadvertent encounter.

4. Fixed/augmented

Footnote: US PPL training includes some hood work and recovery from unusual attitudes. My training (maybe 1 hour) had lots of shadow AIs…the actual 10 hours “real” training was some genuine competence in keeping upright. /dead horse redundancy.

[Gabriel]

draw a Venn diagram

I tried to do that until I faced the set of "all sets that do not contain themselves", and didn't know where to pace this set because if it contains itself then it doesn't, and if it doesn't contain itself then it does.

Squids, please help.

[elaw]

Sounds like you need one of these: https://www.kleinbottle.com/

[ocelot]

My feeling is that unless your interest in flying is specifically limited to good-weather things (e.g. aerobatics), and in particular if you're ever using the plane for transportation, you should get your instrument license for real and keep current. Otherwise you're eventually going to end up in a situation where you have reasons to go but the weather is marginal, and that leads to pushing the limits and eventually getting into trouble.

Not that having the instrument rating prevents the weather from being marginal for IFR flight, but that's both a lot rarer and also tends to involve weather phenomena that are recognized as consequential by non--pilots. That is, it's one thing to e.g. miss the kid's birthday because there's a blizzard on and another because it's cloudy with a chance of showers. Also, the process of getting an instrument rating gives you experience that makes it easier to make these decisions correctly.

(On disorientation specifically, I am probably never going to get direct experience myself, unless maybe museums start getting full-motion simulators, which is why I periodically raise the point: it's to try to mine other people's experiences.)

[Gabriel]

On disorientation specifically, I am probably never going to get direct experience myself, unless maybe museums start getting full-motion simulators, which is why I periodically raise the point: it's to try to mine other people's experiences.)

Full motion flight simulators don't recreate the type of motion that cause somatogyral illusion.
More specifically, they don't roll when you bank and spin when you turn.

What they do is:
They tilt to match the direction of the apparent acceleration vector with the gravity vector. For example, they tilt back when you pitch up at constant speed, but they also tilt back when you speed up at constant pitch.
They do very short-amplitude jolts in X, Y and Z as well as in pitch, roll and yaw to simulate turbulence and sudden control inputs. They use an algorithm called acceleration onset cueing, in which a sudden acceleration (both linear and angular) is replicated to recreate the very initial sensory response but it quickly decays to zero and even becomes negative (opposite to the acceleration that it is simulating) in order to restore the simulator platform to the origin of coordinates.

G-forces, angular motion and linear and angular accelerations (beyond the onset) are not simulated.
As such, these simulators are totally inadequate to simulate the sensory feeling that happens in a slowly developing spiral dive, or when you are in a turn and change the angular orientation of your head.

There are a few custom-built simulators mounted in a fully spinning platform that can partially simulate some of these effects, which they are in fact designed to experience these effects and not to actually simulate a specific plane.

Also, some of the very early flight training devices (GAT-1, which stands for General Aviation Trainer 1-engine) looked like a Cessna 152 cockpit enclosed inside a cartoon airplane and those had a 3-degree-of-freedom motion that would actually match the pitch and roll (up to the stops) and spin 360 degrees in yaw. These were better to replicate somatogyral sensations but was crap to simulate any other sensation. For example, a glass full of water would spill in a turn no matter how well coordinated, and you would not feel being pushed back against the seat back when accelerating. That is one of the trainers I used which I mentioned in my previous comment. The other one I used was a GAT-2, a Baron cockpit mounted in a 2-DOF platform which would replicate apparent acceleration vector direction and some vertical and roll for turbulence. While perhaps not apt for spatial disorientation simulation, it felt more realistic in anything else.



Pictures of the GAT2 are very difficult to find online but you have one in this article which discusses mainly the GAT-1.
http://www.aerospace.utoronto.ca/pdf_fi ... ghtsim.pdf

[3WE]

It appears I am the only one to be disoriented. Windows covered by snow…ease the clutch out, back 30 feet…lateral sensations fade, depress clutch, brake gently…HOLY SHIT, IM STILL MOVING AND ABOUT TO CREAM THE BUSHES…SEND ALL 3000 PSI TO THE BRAKES!!!!! MAJOR LURCH versus what I was expecting.

[ocelot]

Full motion flight simulators don't recreate the type of motion that cause somatogyral illusion.
More specifically, they don't roll when you bank and spin when you turn.

Well, then I'll probably never get a chance, since even if someday I get around to taking a flight or two there's no realistically foreseeable situation where I'm doing actual instrument lessons.

Oh well.