In 1923, the United States Army (there was no U.S. Air Force at that time) set a
ID: 1793882 • 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 36 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 2.31 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. Number m/sExplanation / Answer
Here (2.31 min/transfer) x (9 transfers) = 20.79 min of total pumping fuel.
&
(687 gal) x (231 inches^3 / gal) / (20.79 min) = 7633.33 inches^3/min
Cross section-
x (1.45 inches / 2)^2 = 1.65 inches^2 (cross-sectional area of the nozzle)
(7633.33 inches^3/min) / (1.65 inches^2) = 4624.96 inches/min = 6.4287 ft/sec=1.96075 m/sec!