In 1934
Northrop proposal for a new US Navy dive bomber base don the Northrop A-17
light attack bomber. A prototype was ordered and first flew in July 1935,
designed XBT-1. After a series of service trials, an order was placed for 54
BT-1 models. The first production batch was fitted with the 825hp Wright
R-1535-84 engine. However, the last one off the production line was fitted with
a 1000hp R11820-32 engine and designated XBT-2. Further modifications followed,
and alter the Northrop Corporation became a division of Douglas
in August 1937, the aircraft was redesigned XSBD-1.
It was June
1940 before the US Marine Corps started to receive a batch of 57 Dauntless
SBD-1 with their distinctive, large perforated flaps. A few weeks later, the US
Navy ordered 82 SBD-2 aircraft
