The B-36 Peacemaker was one of the first bomber designs to use a noticeably swept wing in the era of propeller flight.
Responding to the US Army Air Forces‘ requirement for a strategic bomber with intercontinental range, Consolidated Vultee (later Convair) designed the B-36 during World War II. The airplane made its maiden flight in August 1946, and in June 1948 the Strategic Air Command received its first operational B-36.
The B-36 was powered by six Pratt & Whitney R-4360 engines and later variants (such as the B-36J) had additional bursts of speed thanks to four General Electric J47s.
But why did the propellers on the B-36 Peacemaker face backwards?
‘The backwards taper of the wing would make the blades of the prop come too close to the leading edge of the wing.
‘There is no concern of a strike, since they are impossibly stiff, it’s just that the prop would lose a lot of efficiency as the close surface of the wing behind the propeller would cause a disruption to the airflow.
‘The rear of the wing was still effectively straight, so it made more sense to use a pusher design.
‘Additionally, the plane was huge. The wing thickness was so large it could effectively house the engines inside the wings, so putting them out on protruding pods was unnecessary, the way it was for bombers like the B-17.
‘This backwards sweep reflects the new reality of aeronautics design at the time, where higher speed aided by back sweep was the norm. Virtually all aircraft from this time reflect this new trend, seen in bombers designed just a few years later like the B-52.
‘Compare this to earlier bomber designs like the B-29
‘or the B-24.’
‘That not only had straight leading edges, but also wings that were too small to completely encase the motors.’
Photo credit: U.S. Air Force