tinyclark Posted November 17, 2014 Share Posted November 17, 2014 As pilots, were any of you taught how the prop slipstream affected wing lift? If so, is there so little effect that it is negligible? Does it affect the horizontal stabs more than the wings? Quote Link to comment Share on other sites More sharing options...
tinyclark Posted November 18, 2014 Author Share Posted November 18, 2014 Let me ask in a different way. If you lose an engine during flight, does the aileron have to be trimmed at all to compensate for the loss of the engine? Someone must know this. Quote Link to comment Share on other sites More sharing options...
PerfManJ Posted November 18, 2014 Share Posted November 18, 2014 The prop slipstream has a large effect on wing lift, especially at low speeds. This is referred to as the "powered lift" portion of the total wing lift. The magnitude of powered lift is typically correlated to "thrust coefficient" (Ct). It all comes down the difference between the free-stream air velocity and the induced air velocity behind the props: the larger the difference (think high power and low speed), the larger the contribution of powered lift. In those conditions, the loss of an engine would cause a rolling tendency toward the dead engine. To get an idea of the powered lift present on the C-130, compare the normal and max effort takeoff speeds. Normal speeds are based on "power off" stall while the max effort speeds use the "power on" stall speed. Quote Link to comment Share on other sites More sharing options...
Dave in WV Posted November 18, 2014 Share Posted November 18, 2014 deleted Quote Link to comment Share on other sites More sharing options...
tinyclark Posted November 18, 2014 Author Share Posted November 18, 2014 Thanks PerfmanJ, anyone else? Quote Link to comment Share on other sites More sharing options...
donwon Posted November 20, 2014 Share Posted November 20, 2014 When I got to Sewart, I was sent on the rookies quest for some "Prop wash". One of the guys in supply just happened to have a quart can and loaned it to me. I took it back to him after showing it to the rest of the crew. Quote Link to comment Share on other sites More sharing options...
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