Physics Help

[anksta]

Sorry Dons for posting another homework thread but I have been at this question for around 7 or 8 hours now and I am no nearer to gettin started than when I started.

The question is:

An Aeroplane weighing 250000N has a wing loading of 3125Nm^-2 and its Drag equation is given by

CD = 0.016 + 0.04CL^2

Calculate the minium thrust required for straight and level flight.

That is just the first part of a very long question, I think I can do the rest of it if I can get this first part done, so far all I have is the area of the wing is 80m^2.

Any help would be great. Not looking for a specific answer, just someone to suggest a forumla or something I might have missed. Used everything I can find in my books and on the internet, but obviously, I've missed something otherwise I would have done it.

Thanks

 

[anksta]

thanks mate.

Does no one know?

 

[anksta]

Erm, not sure why power is being discussed.
Thrust is a force, and the force must be equal to the drag. So work out the velocity for level flight by lift generated = weight of craft, then see how much drag is induced given said velocity, and the thrust required is equal to that.

how

 

[anksta]

no, thats the point

 

[anksta]

ok fair enough, thanks for tryin, its degree level engineering by the way.


Anyone else have any ideas, would be appreciated.