Register to reply 
Calculate the density at which the available thrust is equal to the minimum drag 
Share this thread: 
#1
Oct3112, 05:23 PM

P: 20

Calculate the density at which the available thrust of a jet propelled aeroplane is equal to the minimum drag for the full fuel load case. Use the simplest assumption for the variation of engine thrust with density.
Wing area, S = 29.5 Weight, W = 88000 C_{D,0} = 0.02 k = 0.044 Max thrust (at sea level) = 16000N C_{T} = 1.7*10^4 I use the formula Dmin = 2((C_{D,0}*k)^0.5)*W = 5221N The problem I have is that I can't work out the density without the velocity but there is no way to relate velocity to drag without density. Where do I go from here? 


#2
Nov112, 07:44 PM

HW Helper
Thanks
P: 5,344

If you care to revise your posting, supplying the units and explaining what each of the three coefficients is, I'll take a look at your problem.



Register to reply 
Related Discussions  
Points of action for thrust and drag forces and liftdrag ratio  Aerospace Engineering  1  
Minimum thrust of engines at liftoff  Introductory Physics Homework  2  
Speed of Minimum Drag  Advanced Physics Homework  0  
Thrust,drag and lift on airplane Question  Advanced Physics Homework  2  
Calculate hydrostatic thrust  Engineering, Comp Sci, & Technology Homework  2 