Emergency Checklist

[Snowbirdxx]

The crash in Los Alamos made me think about possible causes for an after takeoff crash and how incomplete the Huskys POH is.

Not all of us are engineers and the POH does notr cover all possible ways to minimize desaster. I don´t wanna be the guy who says " I know better " but this post shall bring your attention to not only Husky related solutions in an emergency.

Under all emergencies " Flying the plane " is rule #1.


Mixture

Usually POH say FULL rich for takeoff and landings. That should be " As required by DA "

A too rich mixture on high DA could lead to engine stoppage at worst case, but to reduced climb and takeoff roll preformance for sure. Difference can be more than 100%. So we are no talking peanuts.


Engine failiure

Here we should analyse fast why the engine failed. There are many possibilities.

I list some here with the required action


Fuel starvation- Husky related
Tank empty ?
rock wings to see if there is fuel left in a tank from uncoordinated flight.
If there is some left, lower opposite wing , so fuel can be seen by 5°, prop back to 1500 RPM, manifold to 18" Speed 70 - 80 mph mixture lean till engine sputter. This gives you the most range to a suitable landing spot. FF wiull be in the 2-2,5 Gal/ hr range

Blocked Vent? No air going in the tank, no fuel will flow out. Engine will go lean first, then quit. Same procedure as above to maximise air time, then open window and press the draincup into one wingdrain. This will start feeding fuel to the carb. Continue venting every minute after engine relight....

A mosquito screen or a NMP valve will protect insects from creeping in the vent line and building nests there.

Too much fuel in the carb?
If float gets a leak, it will sink and the carb will flood. Pulling the mixture will bring the engine alive again.


Bad ignition. Switch mags and fly on the good mag only.

Carb ice---covered by most POHs.

Mecanical catastrophic failiure: Connecting rod coming of of a cranckcase, valve falling in a cylinder etc. All this will lead to dramaitc oil loss and restart attemps are not sucessful.

However as long as the crank has not seized, speed to near Vy and pull prop all the way back to maximise your glide distance.


I strongly recommend to do this for training reasons. I mean pulling prop back, not damaging the conrods....

MP to 13 or less the Prop all the way back. Trim the plane at 80 and let the stick go , flaps up. Watch your VSI and the horizont.
Then bring prop forward. You will see the nose drop significantly. Bring the prop back again and you will see the much better glide ratio.



Comments are wellcome.

TomD

 

[trapper]

Good post Thomas lots of good info to ponder. All good information to try and remember in case of an emergency situation. Not watching density altitude especially in our mountain areas is the big one. Thanks

 

[bumper]

If the engine is making no power and windmilling, as TomD says, pull prop back to coarse to maximize glide. This will only work if there is oil pressure, as without it the prop will go to fine pitch and increase drag. Also fully open throttle, as this will reduce engine resistance to turning as it's acting as an air pump.

To improve glide even further, both if there is time to do so and there is a longer distance to glide, then consider stopping the prop from windmilling. This will best be accomplished leaving the prop in fine pitch and with throttle fully closed. Fine pitch makes the prop less efficient at turning the engine at low airspeed and the closed throttle increased engine resistance to turning as it makes it more difficult for the engine to suck in air. Raise the nose smoothly to almost a stall and until the prop stops. Then push over smoothly to Vy. Glide ratio is significantly improved with a stopped prop, as stopped, the flat plate area is only that of the prop itself - - while the flat plate area of a windmilling prop is huge, essentially the whole prop swept area.*

*This stopped prop vs. windmilling prop, and which is less drag question sometimes elicits discussion and controversy. One example to help prove the point is a helicopter in autorotation. As long as the rotor is turning, it will develop lift (and by doing so creates significant drag) and if energy is managed properly the helicopter can land safely with no power. Rotor stopped? Drops like a rock as blades are completely stalled and there is very little drag. Low prop drag is what we need to extend our fixed wing glide, stopped prop is thus best - but only if there is time to safely do so.

bumper

 

[Eric Yould]

This is all good information and it is important to learn in advance what to do. It is difficult to think straight when catastrophic events occur (at least for me), and there is little time for experimentation. I got hit by a drunk driver that was being chased by a cop many years ago. I was wearing moccasins at the time, and after finally figuring out how to turn off the engine with the key that was dangling upside down, I landed pretty hard on my head when I released the seat belt. My next instinct was to kick out a window so that I could escape the vehicle in the event of a fire. I kicked and kicked with my moccasins, but couldn't make a dent in the side door window. While kicking, a good Samaritan ran over and opened the door. I hadn't thought to try the door opener -- major chagrin.

While I have done many dead stick landings during bi-annuals, I hope that I would have the presence of mind to know what do do if one of Thomas' events were to occur with out advance warning.

 

[Ksmith]

I love the words "and the engine quit without warning". I would think the only time it would quit "with warning" is when one runs out of fuel.

One thing I did not see in these posts, if somthing unexpected happens, undo the last thing you did. "Upon lowering the flaps the aircraft rolled hard right" put the flaps back where they were. "Upon changing fuel tanks the engine quit" return the fuel lever to where it was and rethink what happened. There are many instances where this rule works. Unfortunatly it dosn't usually work, like after hearing "watch this" or "oh shit".

 

[bumper]

I love the words "and the engine quit without warning". I would think the only time it would quit "with warning" is when one runs out of fuel.

Edit: I misread your post . . . duh! Which may or may not help explain the following gibberish:

If it were only so . . .

Nope, they do quit without warning, unless you consider the time between the loud "BANG" made by the cylinder departing the case and punching through the engine cowling, and the prop coming to a stand still as adequate warning.

Obviously many failures do exhibit sign beforehand, though some don't. In any case, after any catastrophic failure, it's important to take appropriate steps to avoid the insidious and deadly "tail spin" which often happens shortly after an engine stall.

bumper

 

[RobertMullins]

I'm trying to setup the glide ring feature in Garmin pilot. Does anyone know the glide ratio for an A-1C. Short of going out and doing a test in the plane, I'm on vacation without the Husky.

 

[Snowbirdxx]

8:1 works fine. Just get the prop stopped of semi-featherd asap.

 

[RobertMullins]

Thanks very much.

 

[Ak Kurt]

3 blade MT windmilling comes down like a tool box, 2 blade comes down a lot slower in sink rate and glide ratio.

If engine quits first thing to do after flying airplane (i.e., lowering the nose) is to apply carb heat, if engine failed due to carb ice the engine is no longer developing heat and the residual heat in the exhaust system is rapidly decaying, you want to use what heat is left to heat the carb before it is all gone. After carb heat is applied then you can move on to other trouble shooting items.



Kurt

 

[Snowbirdxx]

Agreed Kurt

But on our carburated enbines next thing if carb heat did not bring the engine alife, is pulling the mixture. If the engine failed because of a sunk float it will then run again.

 

[Ak Kurt]

Agreed Kurt

But on our carburated enbines next thing if carb heat did not brin the enbine alife is pulling the mixture. If the enine failed because of a sunk vloag it will then run again.

Yep, that is a good “step two” after carb heat.

Kurt

 

[FW Dave]

I certainly respect the fact that there is alot of experience in this forum in GA. You guys have flown alot more GA than I have, but for what its worth, Here is my flow from years of flying other types of aero machines. The Process is the same, the content is different per the airplane.

I needed something simple I could remember so I worked on these since I fly different planes.. This is the flow the military beat into our heads modified for prop planes.

Memory items:

1. Maintain aircraft control
a. Nose down.
b. Glide or Land
2. Analyze the situation
a. Carb Heat.
b. indication?, rotation?, Time?
3. Take appropriate Action
G - Gas -- (Valve/Vent/Primer)
M - Mixture -- (Pull/Push/Pull)
P - Prop -- (Pull to glide)
4. Land at a suitable alternate

REPEAT

Do whatever it takes to keep it running

Another form of this I have seen is :
Fly the plane,
Work the problem,
work the solution


My Notes:
Step 1 and 3 are performed in order without hesitation.
Mixture = (Pull/Push/Pull - this is a technique that will fire the engine if the carb is saturated.. Pull.. it fires.. if not, push in.... Pull the mixture when landing is assured.)
I had a situation years ago, and resorted to pumping the primer to keep the engine intermittently firing.
I use the GUMP check (GMP) for the husky. Its something I can remember quickly and have trained to .
see is how important carb heat is in my flow.. see where it falls.
An engine needs fuel and fire if its rotating and not trashed.
Chances are high you are getting fire with 2 mags
If the motor fires, then land at a suitable field asap.
Sort the problem out on the ground
Dont get caught in analysis paralysis.. fly the plane

When I was checking out in this plane, I pulled the power under full power climb on a long strip to see how much room it would take to push the nose down, establish a glide, and land.. its ALOT!. The faster you pitch over to 70-75mph, the safer you will be. The amount of nose down pitch will surprise you if power quits from full power climb. Get the nose down NOW.

The military learned years ago that having something structured to fall back on in a stressful situation brings Order to the mind, and that pilots would calm down, and work the problem. I had an engine problem in an F-16 years ago in Iraq, and My mind Immediately fell back on that flow.. they were right. Then the remainder of the memory items from that emergency flowed. The suitable alternate was a few hundred miles away, so I had alot of time to think about a crippled motor, but it kept running until I landed.. I flew a Flameout glide from over 30K..it quit after landing.. Whew! Seemed like an eternity..