Sikorsky XBLR 3

The Sikorsky XBLR-3 was a four-engine bomber designed in 1935-1936 as a competitor to the Boeing XBLR-1 (XB-15) and Douglas XBLR-2 (XB-19). The original XBLR-3 concept was a twin-boom design with both pusher and tractor propellers and many gun stations; it later evolved into a more conventional four-engine bomber design. The XBLR-3 was the last landplane design prepared by Sikorsky before the company committed itself to helicopters.