The C-124 evolved from the earlier Douglas C-74.
Inside the "clamshell" loading doors there were hydraulic ramps in the nose of the airplane, and an elevator under the fuselage. How big was the opening? Plenty big for hauling trucks, bulldozers, tanks and field guns. If need be it could be quickly converted into a flying machine capable of carrying 200 fully-equipped, landing-ready soldiers in its double decker cabins. More versatile still, it could transport up to 127 wounded soldiers strapped on their litters along with all necessary medical attendants.
The United States Air Force purchased 448 of these planes before production was halted in 1955. (The first flight took place on November 27, 1949.) They were used as airlift support and resupply missions all over the world. By 1970, most were relegated to the Air Force Reserve or the Air National Guard. All active service missions ended by mid 1974.
Here are some interesting specifications of the C-124C. It could fly at a maximum altitute of 34,000 ft. with a range of just under 2,175 miles. Cruising speed was 200 mph. with maximum speeds of 320 mph. It sat 48 ft. 4 in. high, was 130 ft. long, had a wing span of 174 ft. 1 in. It weighed 216,000 lbs. maximum. It was unarmed, and at the time of production cost $1,646,000.
Is it any wonder that a sight such as this would cause a great deal of excitement anywhere it would land?! But in Gustavus, Alaska, in the 1950's, it would be such a rarity as to dominate the conversation for days!
All statistical information courtesy the United States Air Force.