Performance of the Fw 190A on the Deck?

[drgondog]

Originally Posted by Harri Pihl

I'm dealing with power, horsepower being one of the power units but I use SI unit where power unit is watt. There is neither "thrust watts" calculated out; the propeller efficiency formula contain elements for that but I don't actually see it because the formula gives directly the thrust.

And please PM if you are interested about further discussion on this particular subject.

Hari - Thrust is a Force not Power.

The more intersting exercise in aerodynamics is converting Hp to thrust to get the free body equation T=Di+Dp and maintain that equation in balance during steady flight and manuevers. The two most important analytical questions are - what is the real Cdp for that specific airframe, and what is the real Thrust when we only know Bhp at SL, or (rarely, have Bhp at a specific altitude) where the weights and airspeeds and boost are noted

THp and Bhp are not the same as Thrust - and ALL the propeller efficiencies, poweplant states, gearing, torque, rpm, pitch angles, blade geometry, etc are about somehow arriving at equations that give a decent approximation for THRUST.

You throw out simple conversions for an equilibrium state as if they hold true in an integration profile as variables change.

I don't know what you and Crumpp have in past history but I can tell you as and MS Aero Engineering that I listen when we engage in the theoretical because he understands the context of the equations and where they hold true.

I'm not going to bother any more on this thread because I feel that I am talking past you and you probably feel the same.

Go back to the flight tests and compare the 51B-15 with the P51D-15 with the same engines, racjs, etc - just different in weight and explain why the Vmax at Sl is so different when only the weight really changes? you will see it is a LOT more than 1 mph