Performance of the Fw 190A on the Deck?

[Crumpp]

If you want to see the thrust horsepower in the calculation, just convert the power value back to bhp and multiply with n. However, I don't see any point to do that because, after initial conversions, the entire calculation is done with SI units.

So you are now saying you do in fact calculate thrust horsepower. That is a reversal from your earlier claim.

Harri Pihl says:

I don't actually calculate the thrust hp but directly the thrust from the brake hp; the hp chart I used just gives the bhp.

Which now sounds like a falsehood as you do in fact multiple SHP by propeller efficiency to convert it to thrust horsepower. Conversion of units has absolutely no bearing whatsoever. I can say something is 1 meter or I can say it is 1.09 yards. It is still same. Of course I am sure you have a reason why dimensional analysis is wrong too if you don’t even understand parametric study.

I find it very hard to believe anyone with a formal education in aerodynamics would have made such a statement in the first place as we must figure horsepower to determine propeller aircraft performance.

Why? In a power producer we hold power constant and use it to figure thrust. It is a fundamental principle of power producers.

There is absolutely nothing that changes:

Graham I think it certainly has been quite a while since you worked with aerodynamics. From what I understand, it is like riding a bike and it comes back.

You missed the point on the parametric study. The only way to judge the affects of weight is to hold a constant, adjust weight, and measure the results. Otherwise we miss the forest for the trees.

That is the basic scientific method and is generally accepted for aerodynamics and applied physics.

Not doing it leads to false conclusions on the relationships. We wind up with statements like the affect of weight is insignificant because we only see a small reduction in speed.

All the best,

Crumpp