Finn Lassen wrote:

 ..... much cut .....
I'll print a "engine problems" checklist and post it on the
instrument panel.

Do the ignition coils heat up at higher RPM? The initial power loss
"felt" like ignition loss, maybe only on one rotor - thus the vibration.

Here are things I will inspect:
Spark plugs (I did run very rich initially) and cables.
Prop tracking.
Check compression.
Exhaust system for cracks.
Intake manifold for cracks.
E-shaft end play.

Of course I don't want to take things apart if I can avoid it. If the
re-drive had failed, wouldn't it stay failed - something noticeable even
at lower RPMs like 3600?

Again, all comments and suggestions are welcome!

Finn

Hi Finn ...

Your thoughts regarding an "engine problems" checklist are excellent.  Let me
offer this bit of procedure that was drummed into me so profoundly in Air Force
emergency training that I remember it well, to this day.  I was probably one of
the last of the big Recip drivers, but the advice still applies to the rotary ...
even more so than the jets that are flown exclusively today ... yep ... the USAF
is "totally rotary", just jets now.

ENGINE FAILURE or LOSS OF POWER

1. Boost Pumps - HI
2. Mixtures - RICH
3. Props - Full Forward
4. Throttles - As Required

This was to be accomplished quickly and immediately, without even thinking about
it.

The logic is impeccable.  FUEL, FUEL, POWER, POWER.  99% of the problems of a
spark ignition engine are fuel related, NOT ignition ... even if they were, you
normally operate in ignition - BOTH mode anyway, so what's to do?  Of the "holy
triumvirate" of any engine - air, fuel, and ignition - FUEL should always be your
1st suspect, and secondly answer the most vital question, "How much power do I
have left to work with?"  Worry about the rest of the details once you are on the
ground!

Notice the plurals in the procedure.  This was for a multi engine, but the
procedure was the same, as at this point, you did not know which engine was
acting up.  The whole purpose was to recover lost power and keep flying.  Did not
matter which was bad or good, same procedure initially for both engines.

Subsequent identification of failed/failing engine was done VERY SLOWLY, with
both pilots agreeing on, moving hands to, and tapping agreement of correct hand
from other pilot.  (there is nothing more stupid than rushing the feathering
procedure, having one bad engine, and shutting down the good one ... but believe
me, this has been done).  Subsequent shutdown was:

ENGINE SHUTDOWN

1. Throttle (affected engine) - CLOSED
2. Prop (affected engine) - FEATHER
3. Mixture - IDLE CUT OFF
4. Fuel Shut off - CLOSED

Shutdowns were done only in the most extreme failures.  If an engine was failing
structurally (bad jug or swallowed valve), but producing any usable power at all,
it was left running, with reduced load as much as possible.  Fuel cutoff was fire
avoidance; no sense having pressurized fuel going to a possible fire.

Hope this helps,

Dale Smith

 
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