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Old September 17th 07, 03:55 PM posted to rec.aviation.soaring
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Default Pawnee Cooldown Procedures

The following has worked at Skylark North in Tehachapi for around 30
years and was policy at Estrella when Horvath owned it:

Upon release, smoothly increase airspeed to around rough air redline
(120 mph, 100 kts indicated) while smoothly reducng power to remain at
about 2400 RPM. Rich Benbrook, one of my mentors and chief pilot at
Skylark for many years stated it succinctly: "Make the engine sound
the same going down as it did going up". This power setting is held
until in the pattern where the power is slowly reduced, the goal being
to be at flight idle and 70 mph over the fence. I also never get out
of dead-stick glide range of the airport.

If you are in a hurry to get down, roll in full back trim and maintain
whatever bank angle that gives you around 120 mph. This is a lot of
g's to pull all day but it is effective.

The engines at Skylark routinely make TBO and they experience no
cracked cylinders or other problems. We had a 260 hp Pawnee with CS
prop which added the complexity of managing the prop. We slowly
reduced pitch while reducing the throttle. CS props are not worth the
workload, cost or maintenaance issues, IMO.

Many schemes have been tested and ultimately abandoned for this KISS
procedure that works.