Before the 727, the most successful civil airliner (in units sold) was the prewar DC-3; total airline orders prior to 07 Dec 1941 were approximately 800. Soon after Pearl Harbor all deliveries of airline-spec DC-3s were diverted to the USAAF or USN under C-49, C-50, C-52 etc. designations. Of course this continued alongside C-47 and R4D production contracts.
It wasn't until the 1970s that an airliner type reached and passed the 800 mark; that aircraft was the 727.
