Thorp Air Command - T18.net

Guys,

I was out for my second Thorp flight since last fall. I played around with power settings and found that by cruising at 2200 rpm and 24" , I got 160 mph where as last fall at 2350 squared got me 155 mph at best. This is with a 160 hp IO-320 and C/S prop. Looks like there is something to the over squared setting that are being suggested.

I will have to play around a bit to see if there is a definite sweet spot that I can percieve.

Oh, yes it was good to see that I still remembered how, and was able to use the plane again after a 6 month period of not flying.

Jim Mantyla

I believe that the "squared" concept is from the days when we worried about overboosting an engine. Most of my flying was with round engines and it was standard to carry a higher manifold pressure number than RPM number-- unless you were using a power setting that was above cruise power.

As a past USMC C-117 (Super DC-3) pilot, we always had a higher MAP than RPM and were restricted from less MAP than RPM because it caused under boosting and piston slap.
GK N444DD

*** admin posted for Graham Kerr ***

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