Noting
the success of the Lockheed 14 based Hudson in RAF service, Lockheed
proposed a militarized Lockheed 18. The
RAF ordered 675 which began entering service in 1941. The
British named the aircraft the Ventura.
The Ventura also served with U.S. forces as the PV-1
and the B-34. The U.S. Navy ordered a long-range
version that was designated the PV-2 Harpoon. Total
production of all types exceeded 3,000.