In 1923, the United States Army (there was no U.S. Air Force at that time) set a
ID: 1793599 • Letter: I
Question
In 1923, the United States Army (there was no U.S. Air Force at that time) set a record for in-flight refueling of airplanes. Using two refueling planes, an Airco DH-4B biplane was able to remain in flight for 38 hours. During the flight, the refueling planes were able to air-transfer a total of 687 gallons of fuel to the plane in 9 refueling transfers. Assume that the refueling nozzle had a diameter of 1.45 inches and each refueling took 2.39 minutes to perform. Calculate the velocity of the fuel through the nozzle. Assume that the fuel filled the entire cross-sectional area of the nozzle.
Explanation / Answer
now,
(2.39min/transfer)*(9transfers)
=21.51 min total pumping fuel
(687gal)*(231inches^3/gal)/(21.51min)
=34135 inches^3/min
=pi*(1.45 inches/2)^2
=1.6504 inches^2
=(34135 inches^3/min)/(1.6504 inches^2)
=20682 inches/min
=2.87ft/sec.