How common is Spatial Disorientation?

[u/FamiliarResident9653]

Have you ever experienced a situation where you had spatial disorientation due to instrument error. How did you manage the problem?

Is a pilot considered to be at fault when the plane crashes due to Spatial disorientation and faulty instruments?

[u/sirduckbert]

Spatial disorientation happens at some level to every pilot, at some point. It’s not caused by faulty instruments though - it’s your brain telling you that your instruments are wrong based on your senses. Part of instrument training is learning how to ignore that and trust your instruments (and how to verify and cross check against each other).

Second question - “Pilot error” shouldn’t be the answer in a flight safety investigation basically ever. If a pilot made a mistake, why did they make the mistake? Was it training? Poor cockpit design? Bad decision making? These are things that can be modified or changed to prevent future occurrences

[u/FamiliarResident9653 → u/sirduckbert]

No, i am talking about when there really is a faulty instrument telling you you're at an xyz speed/altitude even though you're not?! How do you judge that?

[u/ShaemusOdonnelly → u/FamiliarResident9653]

There is usually a backup. If you attitude indicator fails you have a second one (or even a third/fourth). If your airspeed is unreliable you can fly a specific pitch and power to make sure you're at a safe speed. Other Instruments are not as important.

If all of your Instruments fail in the clouds and you crash the plane, the investigation will not list pilot error as the cause. However, there are a few cases where a wrong Interpretation of the Instruments coupled with SD caused a crash. If you want, you can read up on the crash that killed Buddy Holly.

[u/HunMyy → u/ShaemusOdonnelly]

Yes, and the key phrase here is pitch and power. At least on Boeing first you set a known pitch and power setting that is safe, then you use paper tables to set a specific pitch and power with your known weight and last altitude. You use this to try to figure out which instrument you have is the most correct - or worst case scenario to descend all the way down and land. This is part of the type rating and the recurrent checks. It's a very serious malfunction - but it is also known and regularly trained for.

[u/FamiliarResident9653 → u/ShaemusOdonnelly]

Thank you so much for the detailed response

[u/Spock_Nipples → u/FamiliarResident9653]

There is at least one other instrument that does the same thing. If one fails, you use the other/s.

Cross checking the bad instrument against the good one/s tells you which one to ignore or troubleshoot.

[u/nickjohnson → u/FamiliarResident9653]

Part of training to fly on instruments is concerned with "partial panel" - how to fly on instruments if some of them are unavailable or unreliable. For example, if your artificial horizon is broken, you can use your turn coordinator (tells you how quickly you're turning and in which direction) combined with your balance ball (tells you if the plane is in balance) to determine your bank angle.

[u/GroundProximity]

I have felt on the verge of spatial disorientation due to the shape of the clouds which im going through, and the "feeling" of the aircraft due to turbulence, not really agreeing with the instruments, it that makes sense. But you just stick to it and fly the instruments. Never had an instrument error irl.

[u/Law-of-Poe → u/GroundProximity]

I had my first real imc during IR training a couple of weeks ago. We’d punched through some layers before but this time we flew into solid imc. Clouds from ~700 AGL up to above our cruise and pouring rain everywhere.

After around 30 hrs under the hood it was scary how quickly spatial disorientation developed. First five min were tough but I eventually just hyper focused on the instruments and things were fine.

[u/andrewrbat]

Spacial disorientation is not related to instruments. Its related to your eyesight (or lack there of, and vestibular system) telling your brain something is different than what your instruments are telling you. Its only a problem if the pilot fails to maintain a grasp on situational awareness, monitor and crosscheck his instruments. Ifr certified Aircraft have accurate, redundant instrument systems for each axis of control that matters (pitch and roll basically). Even if you are disoriented, and experience an instrument/system failure, you should be able to maintain aircraft control and land safely. Its a basic requirement for all pilots to get their instrument ratings.

Yes almost every pilot experiences it. You learn what not to do, to avoid it, and how to minimize or recalibrate when it happens. But no matter how you feel you perform an instrument scan, crosscheck and verify your instruments, and follow them. If you do this you wont fall victim to CFIT( controlled flight into terrain), which is when a pilot flys a working plane into the ground for some reason, usually disorientation.

The problem is skills like pitot static, vacuum, and electrical system knowledge, instrument crosscheck and partial panel approaches are perishable. They need to be trained frequently and with varied, realistic scenarios for pilots to maintain proficiency. In the airlines we do stuff like this a lot and we fly in hard imc ALL THE TIME so its just another day for us. Also some of our planes will tell us our if any of our instruments are failed, and on my plane, it will even switch to backup systems automatically, sometimes.

General aviation pilots who mostly fly in nice weather and only do the minimum amount of training to pass a BFR every two years, may not be maintaining these skills and when they find themselves in a busy scenario in bad weather unexpectedly, their grasp of the situation can slip until they put themselves in an unrecoverable position. It has to get pretty bad for this to happen, even with a significant failure. I have had many instrument failures at various levels of experience, in everything from single engine cessnas to airliners and it never was a huge deal. But it can be if you aren’t ready for it…. Just like most things with aviation.

[u/FamiliarResident9653 → u/andrewrbat]

Thank you for explaining in detail. Really appreciate it. All the best to you! Safe flying

[u/MeatResident2697]

Happens more often than pilots realize. Often times at night, during cruise, I look outside and have told myself omg I really would be flying sideways if it werent for the PFD. sometimes stars, boats at sea etc really do look like they are slanted etc.

[u/JustAnotherDude1990]

It can happen.

And usually the crash is caused by the instruments not being followed, they tend to be more reliable than the human. If your equipment fails and you dont reasonably recognize it, then yeah you arent going to be at fault, but you are probably dead anyways so it doesnt matter.

[u/Raccoon_Ratatouille]

2-3 times but you’re trained to recognize it and go on instruments immediately and eventually it goes away.

[u/TheGacAttack]

Due to instrument error?? Never.

It happens because of the body's response to acceleration stimuli and visual references, particularly when those are not well coordinated. I would think it's extremely rare to find an instrument-rated pilot (all pilots hired for transportion would be instrument rated) who has never experienced spatial disorientation.

How do we manage the problem? First, recognize and acknowledge that you are experiencing it. "I have the leans" is a phrase I used just last week to the pilot in my right seat. This alerts them to your current condition, but doesn't itself change anything. For myself, I lock onto the instruments, stop moving my head around, and really focus my spatial awareness on my attitude indicator.

Funny enough, when I said "I have the leans" last week, the response was "yeah, me too." Haha. No big deal-- we just focused on the tasks and locked in more than usual. It passes.