Consolidated foresaw a market for a large transport to be used by both
civil and military operators and started the design as the Model 39 in
early 1943. After the merger of Consolidated and Vultee the type was
continued as the Convair Model 104. Convair was the trade name of
Consolidated Vultee after the 1943 merger.
To produce an aircraft in a short time it
became a hybrid: the wings, engines, single vertical tail and landing
gear of the PB4Y-2 Privateer (the ultimate US Navy version of the B-24
Liberator) were mated to a entire new circular-section fuselage.
The US Navy became interested and signed a letter of intent for 253
aircraft in March 1944. The first prototype NX30039 (c/n 1) was flown
for the first time on April 15, 1944 piloted by Phil Prophett and his
crew. Due to design deficiencies the Navy cancelled its order but Convair
received permission to purchase and complete the second prototype in
Navy colours.
Thus the second aircraft was completed as the Convair 104 XR2Y-1
and fitted with R-1830-65 engines NX3939 (c/n 2) made
it first flight on September 29, 1944. Eventually this aircraft was
given the US Navy registration 09803. American Airlines operated the
first aircraft, named City of Salinas, with the support of Convair
for three month transporting fresh fruits between Salinas and El
Centro, California and cities in the east like Boston and New York.
In airline service the Liberator-Liner would have carried 48 seated
passengers or 24 in sleeping berths. A cargo of 18,500 lb (8,392 kg)
could be loaded straight from flat trucks into the aircraft through
large fuselage doors. However, the type could not compete in
performance with, and was much less powerful than current aircraft
and as there was no other interest in the design both aircraft were
scrapped in 1945.