"Michael" wrote in message
ups.com...
Jim Macklin wrote:
Get a better and more qualified instructor. 100 hours is
very little time in a particular model, but this guy is
either ignorant or you didn't understand him.

Actually, you're displaying the ignorance here.

The syncrophaser is used to get both props turning at the
same speed and with the blades in phase to reduce noise.

Correct, that is the primary purpose. However, its range of command is
limited - generally 25-50 RPM. Many also have an indicator (the needle
the instructor is talking about) which tells you which way to make the
adjustment to bring the props within the range of command of the
synchrophaser. Since the prop governors used in piston airplanes are
proportional-only controllers (no integral component) the RPM on the
failed engine WILL drop - and it will drop by enough to take it out of
the range of command, though not enough to be obvious (or even
noticeable) on the average GA tach. In that case, the needle will
become an effective indicator not only than an engine has failed, but
which one.

In
any multiengine aircraft, you identify a failed engine in
positive steps. The problem with the in-line airplanes is
that only reduced take-off performance (reduced climb)
alerts the pilot to an engine failure.

Only if he ingores the information provided by the synchrophaser.

Michael


Hi Michael,

I've got some Skymaster time, and I'd have to go with Jim. I've used the
tach to determine the failed engine, but have never used the synchrophaser
as you describe, nor have I heard of anyone who does. If that little wheel
in there is spinning to the left(at high rpm), does that tell you it is the
front, or the rear engine? Also in the event of an engine failure, the
manual tells you to turn off the synchrophaser so that it doesn't limit,
even slightly, the rpm of the operating powerplant. It may even be on the
"before takeoff" checklist. In my case we only blew off one cylinder head on
the rear engine. There was no indication on the panel, just a "BAM" as
reported by a rear seat passenger just after rotation, and a report from the
tower of "heavy black smoke, from the rear engine". We climbed to pattern
altitude, shut down the rear engine(smoke turned white), and landed
normally.

Al

p.s. This was on a trip to Seattle with 6 pilots in the airplane. My flight
instructor was in the right seat, and I was flying. Immediately after
landing, I turned off the active at the first intersection, and as I was
braking to a complete halt, went through my "Mixture/Master/Mags" shutdown,
and turned to the right to tell the flight instructor to evacuate. He wasn't
there. He was about 75 feet away, lighting a cigarrette. He had bailed out
just after we left the active. No way you'd catch him in no crashed
airplane.