How many horsepower does it take to overcome induced drag in a cessna 172r at 120kts clean?

Question

This is a tricky one so you will need most all formulae to a CPL level. I answered this question within .01 of a hp in my class. The instructor went a pale grey colour. I just closed my eyes a pictured everything knowing the weight of the plane and visualising the profile and airflow then visualising the percentages of drag breakdown and referencing them against the total horsepower. The answer got narrowed down with a "feeling". That the best i can explain it. I loved that day. So many times the class ridiculed me for being eccentically extroverted.

The class was split in 2 4 a quiz. I was in the dumb team. The top of class guy that I was always just behind in exam marks was in the other team. our team was sunk. we couldnt really even begin the equations on paper. The other team was getting an answer (wrong). We had to think of something quick. I closed my eyes and it just happened. The look on their faces! Were not meant to be able to answer this question it was just for fun

Answer 1

Misconception.  Why are you specifying the speed and configuration?

Answer 2

I can't think of a single reason why this would have any importance to flying any aircraft.

Answer 3

Not being able to even balance my checkbook I can't imagine how I managed to actually be paid for flying airplanes and helicopters all over the world. Hey, I was wondering,.......ah fuget it.

Answer 4

But you neglected to give us the most important details of your calculations!  Did you solve this by converging on a conical least-squares representation of the inverted ratios, or did you apply asymptotic vector analysis to the salient features of the profile?  It makes a big difference, you know, in how thoroughly we understand the demonstrated competencies in this action.

And were you required to demonstrate orthogonality?  If so, how did you resolve the issue of quadrature?  Did you apply the root-mean-square of the variance equations, or some new solution not commonly used?

We are waiting enthusiastically to learn more about these crucial details of your ground-breaking work.

Please keep us informed.  Congratulations!

Answer 5

Sounds like you are just bragging...

Not the right forum for that, dude...

This is the aircraft section - for questions about aircraft and flying.  Let's keep it that way, please...