Which B-17s pioneered early warning?

Short answer

The pioneers were B-17Gs of the United States Navy, although the sources disagree on how many: one counts forty-eight acquired during 1945 to carry airborne early warning radar; another, thirty-one more received after the war, redesignated PB-1W and fitted with AN/APS-20 radar. VPB-101 received its first radar-equipped PB-1W in January 1946.

Published: November 4, 2026 · Updated: November 4, 2026 · Edited by Above Ten Thousand · Editorial policy

Sunset silhouette of flying fortress, Langley Field, Va

The B-17Gs that took radar to the air

According to one source, during 1945 the United States Navy acquired forty-eight B-17Gs for the purpose of carrying airborne early warning radar. The Navy had decided to replace some vulnerable ships with aircraft carrying the APS-20E search radar. Another source says that, once the war was over, the Navy took on thirty-one more B-17Gs, which were redesignated PB-1W and fitted with the AN/APS-20 radar, with which the equipment and procedures for airborne early warning were developed. The sources do not agree on the exact number of aircraft converted.

The debut in squadron VPB-101

The Navy squadron VPB-101 received its first PB-1 in September 1945, an aircraft not yet fitted with radar. Its first radar-equipped PB-1W did not arrive until January 1946.

The B-17 beyond bombing

A B-17F with serial number 42-30190 was converted to serve as a tanker aircraft. The B-17E 41-2595, named "Desert Rat", was converted to the cargo or troop transport standard.