The Thomas-Morse MB-4 mail carrier of 1920 had a centerline tractor/pusher engine nacelle pod in the middle, and twin fuselages from surplus MB-3s on either side. The bad characteristics included one fuselage tended to take off before the other, no communication between cockpits, and excessive motor vibration.

 

One went to the USPO but was never used in service and scrapped in 1921. Three went to the US Army (AS64306, AS64373 and AS64374); the first one to McCook Field as P-172.

 

 

Engine: 2 x Wright-Hisso H, 300hp

Wingspan: 45'6"

Length: 25'5"

Useful load: 2010 lb

Max speed: 140 mph

Cruise: 122 mph

Single-engine cruise: 100 mph

Range: 600 mi

Seats: 2