General Hap Arnold of the United States Army Air Forces was concerned that this weapon could be built of steel and wood, in 2,000 man-hours and approximate cost of US$600 (in 1943). To put this figure in perspective, a Boeing B-29 Superfortress cost about 1,000 times more, and still about 100 times more when taking into account its 10 times higher payload (20,000 lb compared to 850 kg for V-1)—payload, which cost has to be added (while it is included in V-1 cost)—with the additional drawback of requiring (and putting in danger) 11 flying crew members (which generally are considered to cost far more than the aircraft itself, with costs of recruiting, training, housing, feeding, pensions and pay, equipment, etc.).