Mike; Partial throttle yields maximum endurance. This is really valuable in
tailwind conditions, where it can result in skipping a fuel stop! My
Beechcraft drank 14 gals/hr at 75% and as low as 8 gals/hr at partial. More
haste, less speed!
Most aircraft have minimum induced drag at just above stall, and here you
need partial power to maintain level flight.
When I flew off my 40 hrs. for my Osprey airworthiness Cert. I loitered at
2100rpm over the airport environs for a good part of the required hrs.
Diesels, which are never throttled, gain most of their efficiency, not from
pumping-loss reduction, but by higher compression ratios and a difference
energy cycle (Carnot vs. Otto). Peter
The engine, being basically an air pump, is most efficient without anythrottle
plates interfering with the flow of air into the engine. Flyingat cruise with
partial throttle doesn't compute at all.
