Spatial Disorientation

iflyforfun

iflyforfun

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iflyforfun
Just read a post by MAKG1 that matches up with much I've been told, but differs a bit from my VERY LIMITED IFR experience and I'd like to get some thoughts.

MAKG1 - "In IMC, you use the artificial horizon and several supporting instruments instead of the real horizon, and you try to ignore your butt because it's often wrong with no visual references."

It's the "ignore your butt" part I'm curious about. I only have a grand total of 5 or so hours actual instrument during my aborted training, but I also have several hours over the coast of Florida at midnight with very few visual references.

So, in all cases, I was super-aware. During some of my training, it was pretty rough with heavy rain and water playing tricks on pitot-static system and the airspeed bouncing all around. That said, I was REALLY watching the artificial horizon and I never felt the disconnect between inner ear and instruments. It was all new enough that I was uber paranoid and cross checking the artificial horizon to the turn/bank all the time to make sure I didn't have a vacuum failure.

My assumption has always been that when the brain gets disconnected when not watching the instruments ... kind of like a DG precessing and getting off-course if not manually corrected every once in a while.

So, does spatial disorientation usually occur when you take your eyes off the instruments, or can it occur for other reasons during part of a regular scan. I've always thought that taking extreme care when checking the map, programming the GPS, leaning down to switch tanks (thus losing instrument scan and throwing inner ear around), etc would have a big impact on avoiding spatial disorientation.

So, how far off am I?
 
I'm not an instrument pilot, but I have some time under the hood, and have done some night flying that, while legally VFR, required that you be on the instruments.

So, I can't answer all of your questions, but I will say that I never experience significant spatial disorientation until the AI is covered up. When all you have is pitot-static instruments and a compass, it's easier to lose your bearings—for me anyways.
 
In certain situations it can happen even when your looking at the attitude indicator. Doesn't happen often but I've have it happen once or twice.


Check out aim 8-1-5.
 
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MachFly said:
In certain situations it can happen even when your looking at the attitude indicator. Doesn't happen often but I've have it happen once or twice.


Check out aim 8-1-5.
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This. Sometimes it is just the motion of the aircraft that gets your body out of whack regardless of whether or not you are looking at the instruments.

I have not experienced Spatial-D myself, but have a few helo friends who have gotten it flying instruments in helicopters. Typically involved rolling out of turns in IMC.
 
Kind of like the line about stalls being possible at any airspeed and in any attitude -- you can become spatially disoriented with any amount of instrumentation available/in your current view. The key to dealing with the problem is being able to read and interpret the instruments, and combine the data from the whole set of instruments to determine where you are and what attitude you're in.

And don't rely too much on the AI to the exclusion of the other instruments, because AI's have been known to fail (either internally or due to loss of power). Scan and cross-check, scan and cross-check...
 
What Cap'n Ron said. But also remember with night flying not only do you have to worry about spatial disorientation, but a slew of other things as well. When I got my PPL I think I had a healthy respect for avoiding clouds, and night flying. In fact I did not do any night flying until I got my IR rating for that reason. I have read too many reports and descriptions of night flying that in my mind made it unsafe FOR ME until I had a good grasp of how to fly by instruments. I have not experienced spatial disorientation, but it may be something I will try to experience when I do a BFR, or my six month informal review with an instructor.
 
I've experienced it. Long cross country, VFR. Eyes outside on horizon...

"Why am I struggling so much to hold heading????"


CFI "you're in a right bank, look at your attitude indicator"


Turns out the "horizon" was a perfectly straight, but slanted cloud layer that I had been tracking for awhile.

WTF...Roll wings level off instruments. Now I feel like we're in a turn even though wings are level. Utter confusion ensues.

Took a LOT of will power to believe instruments and not go back to what "felt" straight and level.

Great lesson.
 
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Ron Levy said:
And don't rely too much on the AI to the exclusion of the other instruments, because AI's have been known to fail (either internally or due to loss of power). Scan and cross-check, scan and cross-check...
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If I'm not mistaken, the FAA does not consider the AI to be a primary instrument for most maneuvers, at least as far as the Instrument written test goes.
 
Fearless Tower said:
If I'm not mistaken, the FAA does not consider the AI to be a primary instrument for most maneuvers, at least as far as the Instrument written test goes.
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Please don't get me started on that awful primary/supporting method of instrument flying. :vomit: After 40-some years, I still have to read up on it when prepping someone for the instrument written. Give me control and peformance any day of the week.
 
Ron Levy said:
Please don't get me started on that awful primary/supporting method of instrument flying. :vomit: After 40-some years, I still have to read up on it when prepping someone for the instrument written. Give me control and peformance any day of the week.
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I knew this when I took my IR checkride, and had figured out the hows and whys. However, in practice I must admit my scan involves everything available to me(G1000(PFD, MFD) and back up instruments), and I am constantly cross referencing data from each instrument to make sure they agree. It has become sort of second nature for me.
 
What I meant by that comment was that your body feels accelerations much more than it feels attitude, and there is a long list of ways that can fool you, in the absence of a visual reference.

One easy-to-try example (with another pilot flying) is to close your eyes and have the pilot slowly roll into a 30 deg banked turn, and then roll out as quickly as possible. While flying straight and level, your body will tell you you're in a moderate turn in the opposite direction. The acceleration into the turn is small and out of the turn is large. Your body will feel the difference between the two. Then try it with your eyes open. You may feel some disorientation that way as well, but it's a whole lot easier to get out of it.

I'm neither an instructor nor instrument rated (though that will be coming shortly), so try that out yourself rather than trust my word on it. It's not hard to do and it is an extremely informative exercise. But don't do it solo.
 
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When I was getting my IFR ticket I remember the first time my instructor and I launched into IMC, about 1000' AGL shortly after takeoff in a Grumman Tiger. As soon as we entered the clouds my instructor told me to see if I could keep the wings level as we continued to climb, without looking at the instruments. Within 15 seconds he said, "My airplane." In that short period of time I had us entering the infamous death spiral. But everything felt fine to me.

Without reference to the horizon or a functioning AI, your body really doesn't have a clue!
 
Not IFR rated but I have started and stopped the rating enough to have spent a decent chunk in actual given my VFR only status.

Only time I got disoriented was actually in VMC, the overcast cloud deck above me slopped heavily at near the horizon and summer haze made the actual horizon hard to see. I had an overpowering sensation of turning.
 
colojo said:
When I was getting my IFR ticket I remember the first time my instructor and I launched into IMC, about 1000' AGL shortly after takeoff in a Grumman Tiger. As soon as we entered the clouds my instructor told me to see if I could keep the wings level as we continued to climb, without looking at the instruments. Within 15 seconds he said, "My airplane." In that short period of time I had us entering the infamous death spiral. But everything felt fine to me.

Without reference to the horizon or a functioning AI, your body really doesn't have a clue!
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Well, there's always partial panel if your vacuum instruments fail. TC, altimeter, airspeed, compass. Not as easy, but you learned how to do this, too.
 
Ghery said:
Well, there's always partial panel if your vacuum instruments fail. TC, altimeter, airspeed, compass. Not as easy, but you learned how to do this, too.
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Of course. Just trying to keep my answer simple.
 
douglas393 said:
I knew this when I took my IR checkride, and had figured out the hows and whys. However, in practice I must admit my scan involves everything available to me(G1000(PFD, MFD) and back up instruments), and I am constantly cross referencing data from each instrument to make sure they agree. It has become sort of second nature for me.
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And that is as it should be. :yes:
 
Cross check is very important. The attitude indicator got the "leans" (it showed the airplane with one wing down) and had to be replaced.

A year later I accidentally climbed into an overcast, and when I looked at the attitude indicator it showed one wing down. My first thought was "It's going out again." But the cross check with the turn coordinator and compass showed I did have a wing down and was turning.

Carefully leveled the wings and did a slow descent and got out of the clouds.
 
Last I checked the FAA has no TSO applicable to the human ass, thus it cannot be used as an instrument for IFR flight

Sent from my GT-P5113 using Tapatalk HD
 
Still a IFR student here. One flight we took off on a IFR clearance. At 800ft I was in IMC. at 1200 my body told me I was descending and in a left turn. After about 3 seconds I said out loud read the insterments. I realized I was in a right turn gaining altitude. I corrected and then told my CFII I got spatial disorientation, he told me he knew, I asked why did you not help me he said he would have but felt safe and wanted to see if I figured it out and corrected. It was a crazy feeling but kind of glad it happened with a capable CFII with me. I read about this but it is hard to understand until it happens to you.
 
Luvrv8 said:
I read about this but it is hard to understand until it happens to you.
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Indeed, in my event I was on autopilot, compass was steady, DG wasn't moving, both AIs showed wings level, but that false horizon out the front of the plane made me want to say that all that stuff was broken and I was turning!
 
The former military pilots on here will probably remember something like this. In flight school in Pensacola they put a class of us inside a building with a "merry-go-round" contraption that had a mock up of a cockpit. They told us to strap in tight because they were going to spin us around pretty fast and the centrifugal force would throw us out of our seat. They told us they were going to turn down the lights as they spun us up so we could experience spatial disorientation. As the lights went down you could hear a hum like an electric motor turning and a series of lights started running around the room, slowly at first, then faster and faster as the hum of the electric engine got louder and louder. Pretty soon my body started leaning outward from the centrifugal force as we spun faster and faster around and around . . . as indicted by the lights spinning faster on the wall. Soon, I was sure i was going to fall out of my seat, except the seat belt held me in place, cutting into my hips as my body weight pressed outward with the centrifugal force. Soon the humming of the electric motor began to wane and the lights slowed down and soon we came to a stop. The lights inside the build came on and we were told to unbuckle and stand up. Most of us had a hard time standing upright as we staggered around like drunks. Once we had regained our balance the instructor informed us that the carousel on which each cockpit was fastened never moved. It was just a wooden stage. The lights flashing on the wall was what gave us the sense that we were spinning around. And the force of our bodies against the seat belt, as if we were going to be slung from our seats, was simply our visual cues sending a signal to our brains that we were spinning around, even though we never moved. To this day, I am still amazed.

One thing I always concentrated on during IMC flying was to move my head very slowing to avoid upsetting my inner ear. Another was to have set procedures to follow in my scan, whenever I felt like I was getting in trouble I would lighten up on the controls, put the wings on the horizon on the AI and trim it there, check the ball and trim it there, then add or reduce power as required to arrest any climb or descent on the VSI, then adjust my power to a known setting that would give me the airspeed I wanted. I would then continually cross check my VSI and air speed to make sure they were settling in and not increasing in deviations from a wings level attitude on the AI. I was also careful not to chase the VSI in bumpy weather with up and down drafts. Just relax on the controls and allow the aircraft to move up and down without major control input from me. One must trust his instruments and not his senses or bad things will happen. My instrument flying was done with "steam gauges" so perhaps the all glass cockpits have improved things.
 
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I'm always surprised when I hear a pilot who has never experienced spatial disorientation. For me, it was a required part of my private pilot training.

Here's how it happened: My instructor, Bob, took me up for night training from East Troy to Racine, WI -- along the shores of Lake Michigan. On this moonless night, looking out over the lake was like looking into a Black Hole -- no lights or features of any kind were visible.

He told me to fly a heading of 090 -- due East -- and soon we were out over the big lake. I may have had 15 hours at that point, and was instantly on instruments.

Everything was going swimmingly when Bob suddenly covered my panel with his clipboard. There I was, sailing along inside a nice, warm, inky black womb, with no visual references of any kind.

After a minute, I noticed that the engine seemed to be speeding up. I intuited that we must be diving, so I pulled back on the yoke a smidge. Another minute went by, and the engine began to slow down, so I pushed forward a bit.

That was all it took. My inner ear did a back-flip, and I completely lost all sense of up and down. I helplessly said "Bob, I can't fly like this!"

He took the controls and told me to look over my left shoulder. There, in the distance, were the on-shore lights. Instantly, my brain snapped back into "up/down" registration, and all was well.

It was very quiet in the plane as we headed back to our home airport. All he said was "That was spatial disorientation, and it will kill you. Don't EVER eff with it." And I have never forgotten it.
 
Simple Example - After a long climb to cruise altitude, your butt gets used to the pitch up attitude as "normal". When you push over a your target altitude, it feels like you're in a dive. Most students will go back into a climb because it "feels right". Your butt lies!

Instruments - trust, but verify.
 
Spatial disorientation can hit suddenly, like the classic launch into the "black hole effect" or it can creep up on you. I got a real rude lesson trying to hold hover in heavy snow over a boat. Things started to get crazy when the instructions from the hoist operator made absolutely no sense in light of what I thought the machine was doing. Luckily the PNF was on the gauges and let me know I was out of our safety zone and he called for the machine and hauled the collective up into his arm pit. The combination of the swirling snow, the moving lights on the heaving boat and the indistinct horizon put every visual clue I was getting at odds with each other. We backed off while I settled down and went in again. Fun times.
 
Takeoff from New Orleans Lakefront runway 36L (or over any large body of water or sparsely populated terrain) on a clear, moonless night can quickly bring it on if you get tempted to look outside and stray from the gauges....black sky with some visible stars above, black water or dark terrain with intermittent boat or house lights below....doesn't take long at all to wonder which way is up....
 
Threefingeredjack said:
Spatial disorientation can hit suddenly, like the classic launch into the "black hole effect" or it can creep up on you. I got a real rude lesson trying to hold hover in heavy snow over a boat. Things started to get crazy when the instructions from the hoist operator made absolutely no sense in light of what I thought the machine was doing. Luckily the PNF was on the gauges and let me know I was out of our safety zone and he called for the machine and hauled the collective up into his arm pit. The combination of the swirling snow, the moving lights on the heaving boat and the indistinct horizon put every visual clue I was getting at odds with each other. We backed off while I settled down and went in again. Fun times.
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That is why God made the Sikorsky SH-60B. :D
 
The key to avoiding (or RECOVERING from) spatial disorientation is not that just that you know how to fly on instruments but to know WHEN you need to be flying on instruments. Frankly, most students can be thought to keep the dirty side down when told to do so. Where you get into trouble is staring out into the murk and NOT looking at the instruments. Further, if you are in the soup and things start to look odd.. .NOW IS THE TIME to use the unusual attitude training you were taught. An unusual attitude is one you don't expect not just one that your INSTRUCTOR throws at you.
 
flyingron said:
The key to avoiding (or RECOVERING from) spatial disorientation is not that just that you know how to fly on instruments but to know WHEN you need to be flying on instruments. Frankly, most students can be thought to keep the dirty side down when told to do so. Where you get into trouble is staring out into the murk and NOT looking at the instruments. Further, if you are in the soup and things start to look odd.. .NOW IS THE TIME to use the unusual attitude training you were taught. An unusual attitude is one you don't expect not just one that your INSTRUCTOR throws at you.
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100%

I was in the sim last week and got distracted. Saw airspeed going nuts so I did the classic death spiral input of hauling back on yoke since I did not initially recognize the need to level wings. Utter confusion ensued when airspeed did not respond.
 
I've experienced disorientation more than once. I trust the gauges and cross-check carefully but I can feel the discomfort for the first several minutes in IMC. My friends who are professional pilots tell me that doesn't go away.
 
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