Ross Oliver wrote:
: hour at 75% cruise. I've noticed this before, that it never
: burns nearly as much fuel as I would expect. Another thing I
: noticed during the flight that I had never thought much about
: before is that in cruise, the throttle is about 3/4 closed, even
: at 2600 RPM at 7500 feet MSL. Redline is 2700, and opening the
: throttle further would push past redline. I haven't flown any
: other planes in a while, so I can't recall whether this
: throttle position is unusual.

It really sounds like the tach is off. An easy way to check (at least at one
RPM) is to fire it up under some orange sodium lights at night. Run it up to where
the prop "stops" by strobe effect of the lights. Assuming a 60Hz country, a 2-bladed
prop will stop at 1800 RPM, a 3-bladed at 1200.

That's only a single datapoint, but it's quick and easy. I've also used a
laptop with microphone to record the noise the engine makes. A quick frequency
analysis will show the fundamental frequency.

-Cory

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************************************************** ***********************
* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
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