A daft idea to avoid spatial disorientation in IMC...?

[michaeljtbrooks]

Is this avionics idea actually worth pursuing or is it just daft?

https://www.youtube.com/watch?v=PyHr998dvpo
 

I'm a (fairly mediocre) student pilot learning to fly a C152 for fun, but I also tinker a lot with electronics.  I'm surprised at the number of accident reports in GA each year where spatial disorientation was a primary factor (10-30 a year). That makes me think that there are many more close calls we don't know about.

 

My background is in Medicine, so I'm aware that the most powerful sensory cue for humans to determine orientation is peripheral vision. Central vision (staring directly at the attitude indicator) needs some conscious processing for you to figure out attitude. I found some papers about research NASA did in the 1980s and 1990s which demonstrated that projecting a faint gyro-mounted laser line onto the instrument panel reduced spatial disorientation in IMC / night because pilots could see it in their peripheral vision.

 

So I was thinking of prototyping a much cheaper equivalent using colour changing LEDs and a modern silicon gyro chip. You'd stick the strips vertically onto the left and right of your instrument panel, or onto the windscreen pillars, so it's subconsciously feeding you an impression of your attitude without you having to look directly at it.

 

If someone was selling such a thing at a reasonable price, that helped prevent spatial disorientation and was easy to install, would you buy it? 

 

[rgmwa]

Seems like a good idea, not that you should ever fly into IMC as a VFR pilot, but it could happen. What would it cost?

[Moneybox]

Sounds like a great idea. I'm surprised my plane doesn't have an attitude indicator at all. I'm looking for something now to fill that blank 3 1/4'" hole in the dash. I think I'm going to end up with the SuperEco AP that will do both jobs.

[michaeljtbrooks]

I'm thinking "cheap" by aviation standards, certainly less than it'd cost to hire a Cessna 152 for two hours. Maybe $150-$250 (US)? It'd be a one-off purchase, no dumb subscriptions. 

 

It's not intended to be a primary flight instrument, just an awareness aid, so I can avoid a lot of the certification headaches for version 1. This would also keep the cost down.

 

I'm hoping that instrument rated pilots would be interested because if the NASA papers are to be believed, it'd cut down those fleeting moments of spatial disorientation in IMC, so they'd be getting benefit for a lot more of the time than VFR pilots.

 

 

[skippydiesel]

Hi Michael,

 

Great idea - hope it works & can be applied.

 

I thought that for the most part "peripheral vision" is unconscious.

 

When I am flaring to land, I look straight ahead (conscious input) but am judging airspeed & position primarily by peripheral vision (unconscious).

 

If this is true (???) then your orientation strips need to be much further apart - not in the main field of view, as illustrated😈

[BurnieM]

This sim has an attitude indicator.

Like all instruments you need to learn to use it. Why re-invent the wheel ?

 

I believe in Australia we do only 2 hours on instruments for PPL.

I was reading an article the other day that suggested you need 10 hours instrument practise to develop a basic understanding.

Note this is not IFR training just keeping yourself alive in inadvertant VFR into IMC.

Some would argue that getting into this circumstance is a failure of your VFR piloting skills.

 

Edited Saturday at 09:20 PM by BurnieM

[sfGnome]

I’l have to trust you and NASA on the peripheral awareness bit (not saying it’s wrong, just that I have no idea). However (there’s always an ‘however’ 🙂), gyro chips drift pretty quickly, so you also need a magnetometer (and possibly other stuff) to constantly correct it. Have a dig around the web for people who have tried to make homebuilt artificial horizon displays. I haven’t found one that’s been successful, but you might find something. The key thing is that the display and driving it is easy enough; it’s sourcing the reliable attitude information that’s the problem. If you can do that, then you’re away. 

[facthunter]

You fly 'Visual" Mostly by reference to the Horizon. The Artificial Horizon replaces the  true Horizon when IFR and that was referred to as "ATTITUDE Instrument  Flying".. You are correct about the Primacy of what the eye sees in Orientation. 

 Everyone thinks they will be able to SENSE which way is DOWN when in Cloud. WRONG. Dynamic Loads come into Play and your Inner ear semi circular Canals and the "seat of the Pants" feel Play tricks on you. The Pilot MUST absolutely TRUST the Instruments and  a GYRO is an essential Part of it for "rigidity" in space. Hope this Helps.  Nev

[KRviator]

I suspect the issue you will find with the accelerometer will be that in a sustained, balanced turn, it will gradually return to a wings-level indication. Some early experimental EFIS had this issue, and now they use a multitude of sensors combined with GPS and airdata inputs to avoid the issue.

That being said, there would be nothing wrong with installing a small, cheap, D-10A, D-6 on the Coey's panel and using the serial output from that to drive your LED's. I mean no disrespect to your engineering or tech abilities, but it would be infinitely easier than trying to design and build an attitude source that would have sufficient reliability that I'd trust it in the worse-case scenario. Probably be far easier to code as well.

[Bennyboy320]

As a retired airline examiner & instrument rating examiner with over 18,000 hours I still can’t understand why this has to come up every few months, simple airmanship & a sense of self preservation should keep you on the ground during marginal VMC conditions or a diversion if airborne.

 

This is my instrument panel which I deliberately chose when purchasing my Foxbat, not an attitude indicator insight.

 

Continued flight in marginal conditions equates to a DEAD MAN WALKING.

[facthunter]

Haven't you got a RATE turn Needle? . People will continue to get into cloud and they won't be "In Control" Long. You are correct there.  Nev

[onetrack]

Benny, please let us know the critical attitude information that the Hula girl provides? Is it all related to the level of skirt sway??    😄 

[KRviator]

19 minutes ago, Bennyboy320 said:

As a retired airline examiner & instrument rating examiner with over 18,000 hours I still can’t understand why this has to come up every few months, simple airmanship & a sense of self preservation should keep you on the ground during marginal VMC conditions or a diversion if airborne.

 

This is my instrument panel which I deliberately chose when purchasing my Foxbat, not an attitude indicator insight.

 

Continued flight in marginal conditions equates to a DEAD MAN WALKING.

I agree, but people still get caught out. I would rather tip the odds in my favour where possible. I did an AFR a couple years ago and when the instructor asked "What would you do if you flew into cloud?" I pressed the CWS button on the stick, sat back, crossed my arms and said "That!"...then explained what I'd done and why. The autopilot can do a far better job than I ever could, we're wings level, and now I've got time to think rather than spending precious brainpower on keeping wings level in an unexpected situation.

VFR into IMC continues to kill people year-on-year, no matter how much CAsA/FAA/instructors preach "stay on the ground", so anything that helps you survive if you're foolish enough to get caught is a good thing.

[facthunter]

An autopilot doesn't know when it's in cloud. You still have to know where the HILLS are and get out of the Cloud safely.  You can also run out of daylight, OR fuel, mucking around..  Nev

Edited Sunday at 01:29 AM by facthunter

[rgmwa]

40 minutes ago, onetrack said:

Benny, please let us know the critical attitude information that the Hula girl provides? Is it all related to the level of skirt sway??    😄 

When the skirt’s over her head the plane is upside down. Simple, but effective and requires no batteries or gyros. 

Edited Sunday at 02:00 AM by rgmwa

[facthunter]

Wouldn't happen in a barrel roll or Loop. THAT is SO WRONG rgmwa. Nev

[rgmwa]

I agree, Nev. But if it is over her head you might reliably conclude that all is not well.

 

[michaeljtbrooks]

Thanks for the feedback on the idea, sounds like it might have legs so I'll move onto a physical prototype.

 

I've noted the concerns about drift. There are a couple of 9-DoF PCB module packages which include magnetometers and are pretty drift resistant (e.g. BNO085). Cheap enough to give it a go and see how it stands up.

 

For those asking "what's wrong with the primary attitude indicator": Nothing for what it was designed for (deducing roll and pitch when instrument scanning). The issue is that you have to be looking at it, and your brain doesn't automatically turn information presented to your fovea into orientation, it takes conscious processing to do that. Your brain can however turn signals from the peripheral vision into sense of orientation without conscious processing. So this idea is not intended to replace proper instrument scanning or to replace the AI, it's intended to project a sense of the horizon to the edges of your vision.

 

An example use case of this is where someone diverts their gaze such as looking down at Foreflight on their iPad, or fiddling with the radios. They're more likely to ignore false vestibular cues and retain a sense of their orientation if there's something that looks like a horizon out the edge of their vision.

 

In case anyone is concerned about the safety aspects of me building and testing this: I'm going to speak to one of the aero club's instrument rated instructors to see if he's game to try this out. I'd suggest he tests first in VFR then only if it feels ok test again in marginal VFR, then finally in IMC. I'll put in an easy to access "off" switch in case it proves to be a distraction or throws off incorrect cues.

[sfGnome]

Sounds good. Be sure to keep us up to date with progress and testing. I imagine that there’s lots of functional testing that you can do long before you actually put it in an aircraft. 

[facthunter]

Correct/ Effective Instrument scanning is Part of Instrument Flying training, already, but you FLY on ATTITUDE . There's a standard IF Panel Layout. HUD is probably the Best presentation. If you fixate on a performance instrument you will Overshoot continuously. Example. Don't chase airspeed.  Nev

[facthunter]

How many People here Have flown IFR, Properly Rated? . CASA have had the view Teach it and People will do IT. Well People think it's easy and find out the Hard way that it isn't.. You need recency and Have Instruments that You TRUST explicitly.. Nev

[Methusala]

I flew our club's new Jab 170 yesterday with Dynon panel. Mate next to me said that he thought the ball on the display had a significant delay over the spirit ball in front of him. Is this a widespread observation from members who fly with Dynon? Bit of tread drift, sorry.

[KRviator]

I don't have a skid ball in the RV, but can't say I've ever noticed any discrepancy between the Dynon and what my backside is feeling.

[skippydiesel]

2 hours ago, Methusala said:

I flew our club's new Jab 170 yesterday with Dynon panel. Mate next to me said that he thought the ball on the display had a significant delay over the spirit ball in front of him. Is this a widespread observation from members who fly with Dynon? Bit of tread drift, sorry.

I fly with a Dynon Skyview.

I had an idea that the Dynon digital "slip ball" was at odds with reality.

Installed a conventional ball, directly above Dynon display, only to find that it and the Dynon are in agreeance.

This suggests to me that "seat of the pant" determination of yaw, can be psychological.😈

[facthunter]

The real ball is damped by the fluid in the Glass, It's a BALANCE  (slip/skid) only. The Turning "thing" is the ears semicircular Canals. You don't have to speculate about this. It's covered in Human Factors and other references. After a while the inner ear ceases to register the TURNING and if you stop turning it thinks you are going the other way.  The seat of the  Pants detects accelerations and "G" changes. Nothing is there to tell which way you are going unless you SEE it.  Nev