The two decades between 1935 and 1955 were the two decades of the greatest technological change in the history of mankind.
Propelled by war, technology advances quickly.
When my father enlisted in the US Army Air Corp in 1936, he was trained as an aircraft mechanic, working on the B3 bomber, a canvas covered biplane bomber with a tiny payload:
The B3 bomber was state-of-the-art in the 1930's
War is hell, but it also drives amazing technology, and in less than 20 years, America went from creaky biplanes to the B-52 Bomber, introduced in 1952:
In less then 20 years, America went from the stone age to the jet age
After the nightmare of December 24th 1945 when the USAF destroyed their entire inventory of B-17, the government said “never again” and they began hanging-on their old warbirds.
Interestingly, the USAF plans to keep the B52 in service for 100 years, and does not plan to retire then until the 2050’s.