As a multiengine instructor I would never allow a student to
use ONLY the EGT, RPM, CHT or other instrument to verify the
degree and actual failure of an engine. You must close the
throttle on the engine you think is dead, all the way [over
a period of a few seconds] to be sure you have properly
identified the failed engine and that it is in fact really
dead and not just sick. If the yaw changes when you get the
MAP back to 20 inches, that means you have a sick engine and
you don't want to shut it all the way down [unless it is on
fire] at 100,200 or 300 feet. At 500 feet you probably have
circling minimums so maybe you'll prefer to secure a sick
engine, but any examiner I've ever heard of would fail a
student who used the unreliable instruments to identify,
verify and then feather an engine.


--
James H. Macklin
ATP,CFI,A&P

--
The people think the Constitution protects their rights;
But government sees it as an obstacle to be overcome.
some support
http://www.usdoj.gov/olc/secondamendment2.htm
See http://www.fija.org/ more about your rights and duties.


"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
|