You are asked to help design a streamlined dirigible with a length of 600 m and a diameter of 100 m to cruise at 15 m/sec for excursions for retired professors. Your task is to estimate the power required for each of four engines assuming 100% efficient propellers. You are allowed to make the crude assumption for calculating the drag that the surface can be represented as one side of a flat plate formed by unwrapping a hollow cylinder with the same length a diameter. You estimate is about:
a. 20 horsepower
b. 200 horsepower
c. 2000 horsepower
d. 2 horsepower
