Graveyard Spiral

sdfcvoh

sdfcvoh

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I had a thought last week about something I had been teaching avoidance of (by correct use of instruments) which I wanted to pass on. I'm sure most of you reading this have already surpassed this thought, but I'm going to post it regardless just for safety.

If I am ever in a situation that involves loss of instruments, and I am without visible horizon, how will I react? After crapping my pants I plan to do the following...

1) Ignore crap in said pants.
2) Remove power and trim for slower airspeed

I never really had this realization until recently. I'm trying to figure a way to teach this, because talking to students about the graveyard spiral or even the normal situation producing a truly unusual attitude can certainly be remedied by correct use of power and trim...

Discussion encouraged.
 
sdfcvoh said:
graveyard spiral or even the normal situation producing a truly unusual attitude can certainly be remedied by correct use of power and trim...
Click to expand...

Except a graveyard spiral is from an imbalance of lateral and directional stabilities and has nothing to do with power setting or trim. Would you mind explaining your thinking a little more in depth and the scenario?

Decreasing speed certainly slows everything down, so that might be good. That is why I want to understand what you are saying a little better.
 
The best way I've found for teaching proper recovery techniques of spatial disorientation is to emphasize the symptoms and advocate that prevention is the best remedy. With that being said, reduction of power should always be the first step in recovery from a graveyard spiral. I usually tell students: Power, Push, Roll. Power - decrease power and reduce the airspeed that is increasing rapidly. Push - release the back pressure on the yoke and unload the G's building on the aircraft. Roll - reorient the aircraft.
 
sdfcvoh said:
If I am ever in a situation that involves loss of instruments, and I am without visible horizon, how will I react? After crapping my pants I plan to do the following...
Click to expand...

I'm confused... do you mean a catastrophic and unlikely loss of ALL instruments? Vacuum, electric, and pitot-static?

If you just mean a loss of one then you just have a simple partial panel exercise to go through and we should all already be well trained on that anyway.

Maybe a definition of what you mean by a "loss of instruments" would be helpful to the discussion?
 
I was going to say if I just lost my DG instruments which would include the artifical horizon I'm not going to slow down. Reason being is that airspeed is one of my pitch instruments now and by having them slow down and reduce power right off the batt you might end up putting them into a graveyard spiral especially for someone with little experience with partial panel. Once everything is situated than you could slow down if you wanted but I guess dont see the reason to unless your coming in to land which hopefully you would have found vfr by then.
 
Carefully slowing down to approach speed if you are above it may be advisable because the faster you go the faster things can get out of control. Usually exceeding standard rate when partial panel is the way my students put the airplane into an unusual attitude. I had my pulse quickened one day when in actual IMC, student flying too fast partial panel, late on the final approach course intercept, makes steep turn to intercept loses altitude and just says, "your controls"
 
Referring to a total loss of instruments (Vac/Elect)while in the soup... You are flying 100% blind and now you have to make a decision.

1) fly by the seat of your pants? bad
2) try to set the plane up for as safe an aerodynamic position as possible to hopefully make it out alive? better

I couldn't think of any other solution except use low power setting with nose up trim to slow airspeed safely and hopefully descend safely under the clouds. Sort of a quiet day post to encourage discussion...
 
sdfcvoh said:
Referring to a total loss of instruments (Vac/Elect)while in the soup... You are flying 100% blind and now you have to make a decision.

1) fly by the seat of your pants? bad
2) try to set the plane up for as safe an aerodynamic position as possible to hopefully make it out alive? better

I couldn't think of any other solution except use low power setting with nose up trim to slow airspeed safely and hopefully descend safely under the clouds. Sort of a quiet day post to encourage discussion...
Click to expand...

So you have an airspeed indicator, a VSI, an altimeter, and a mag compass left... no need for seat of the pants, you have everything you need right there.
 
I dont understand the need to "slow down and re-trim"

I would try and maintain the same power and trim I had before the gyro failure. Less work.
 
sdfcvoh said:
Referring to a total loss of instruments (Vac/Elect)while in the soup... You are flying 100% blind and now you have to make a decision.

1) fly by the seat of your pants? bad
2) try to set the plane up for as safe an aerodynamic position as possible to hopefully make it out alive? better

I couldn't think of any other solution except use low power setting with nose up trim to slow airspeed safely and hopefully descend safely under the clouds. Sort of a quiet day post to encourage discussion...
Click to expand...

Your proposal sounds like a good way to inadvertantly depart the airplane and die. In light civil aircraft (what I'd presume you are instructing in), the turn needle can be used to establish wings level, and so can the wet compass. Yes, idle if you are racing towards redline airspeed, but aside from that, thrust is giving you airspeed and life. If you have a total electrical failure as well (getting into a very WORST case scenario here), then I guess I would try to use the mag compas to the best of my ability. You also should have some sense of what different airspeeds sound like in the airplane........that could be useful in this situation, not to mention that you can feel gravity (and get a sense of what is upside down) if you aren't loading the airplane up. That said, as long as the goo doesn't go down to mins, you will probably break out before you hit the ground. Better to epic-ly overstress the aircraft and walk away (assuming you break out in some wild unusual attitude) than just chop the throttle and hope for the best. An old civilian flight instructor of mine and her student had this happen to them (took them too long to diagnose a pitot static failure), and they broke out at about 700' AGL inverted and nearly at VNE. They recovered, landed, and proceeded to clean out their panties when they got on deck.
 
Sorry - I mistyped. I meant to say that everything was gone. I mean everything! Same as is you are flying along and you go blind. :eek:

Then what? I know this will never happen - but hey - interesting discussion. How are you going to handle the descent?
 
sdfcvoh said:
Then what? I know this will never happen - but hey - interesting discussion. How are you going to handle the descent?
Click to expand...

If the magnetic compass goes too? What's it going to do, spring a leak? Jump out and hope you land on something soft. The airplane is obviously trying to kill you, might as well get away from it. :D
 
I did have a compass break open on me once in flight. I couldnt figure out why my head was getting wet till I looked up.
 
I know its a crazy situation! But I'm just thinking hey - what is the best way to deal with it...
 
sdfcvoh said:
I had a thought last week about something I had been teaching avoidance of (by correct use of instruments) which I wanted to pass on. I'm sure most of you reading this have already surpassed this thought, but I'm going to post it regardless just for safety.

If I am ever in a situation that involves loss of instruments, and I am without visible horizon, how will I react? After crapping my pants I plan to do the following...

1) Ignore crap in said pants.
2) Remove power and trim for slower airspeed

I never really had this realization until recently. I'm trying to figure a way to teach this, because talking to students about the graveyard spiral or even the normal situation producing a truly unusual attitude can certainly be remedied by correct use of power and trim...

Discussion encouraged.
Click to expand...


Put the aircraft in a spin, hold it until out of the clouds, recover. (hope the overcast is high...) :yup:
 
Hmmm.... simultaneous loss of EVERYTHING is pretty unlikely, but in the interest of conversation....


Maybe break out an empty clear water bottle and piss in it. Then use the liquid as a makeshift level or inclinometer?
 
Really tho - complete loss of electrical in the clouds on a moonless night and you forgot any sort of secondary light? Its not that impossible...
 
fish314 said:
Then use the liquid as a makeshift level or inclinometer?
Click to expand...

A level won't function as a level in an airplane, which is why we have gyroscopes. At best it will give you slip/skid info. Since that reveals the direction of lateral acceleration, it's conceivable that it might provide some bank information. However, slips can be caused by yaw, too, not just a banked attitude, so that instrument would have a lot of noise in it. I bet the pilot would very promptly have the aircraft in an unusual attitude if he tried it.

The pilot has no real hope of controlling the airplane in IMC without a gyroscopic instrument. Best bet is to take the hands off the yoke, begin a gentle blind descent, and rely on the airplane's dihedral to prevent too steep of a bank before breaking out of the clouds.
 
Okay - so I return to the initial question: In a 172 I would pull power and trim nose up full then pull out two twists (usually gets glide speed).

What about other planes?
 
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