Spurred by the success of the A-17 series of US Army attack planes, the Northrop company developed a number of export versions of the A-17 for sales to overseas customers. These were initially known as the Northrop Model 8, but by the time that they were produced Jack Northrop had left the division that bore his name to strike out on his own once again. The Northrop branch was now known simply as the El Segundo Division of Douglas, and consequently these export versions were known as the Douglas 8A or DB-8A, where DB stood for "Douglas Bomber".
The first of these was the Model 8A-1, or DB-8A-1. The Douglas Model 8A-1 was developed for Sweden, which ordered one prototype and parts for a second machine which would act as a pattern aircraft for license production by AB Svenska Jarnvagsverkstaderna (ASJA) of Linkoping. The 8A-1 was generally similar to the fixed-undercarriage A-17, but Sweden opted for the Bristol Mercury as the powerplant, since this engine was already being built under license in Sweden by SFA.
The prototype (company number 378) was powered by a 875 hp Bristol Pegasus XII engine since this engine was generally similar to the Bristol Mercury engine planned for the production version. It was shipped to Sweden on April 22, 1938. The Swedish Flygvapnet designated the aircraft B 5A and assigned it the serial number of 7001. Parts for the second aircraft (company number 410) were shipped on August 8, 1938.
The production version built by ASJA was known as B 5B by the Flygvapnet, and was powered by a 920 hp SFA-built Bristol Mercury XXIV nine-cylinder air-cooled radial. It different from the Northrop-built B 5A in having a domed canopy over the pilot's cockpit and having the radio mast moved from the top of the cockpit canopy to a position just forward of the front canopy. The 64 ASJA-built B 5Bs were delivered in 1940, and were assigned Flygvapnet serials 7002 to 7065.
In 1941, ASJA was succeeded by Svenska Aeroplan AB, or SAAB. SAAB was given a contract for 39 similar B 5Cs (serials 7066 to 7104).
B 5s equipped Flottiljer F 4 at Ostersund and F 12 at Kalmar until replaced beginning in 1944 by the Swedish-built SAAB B 17 light bomber.
Engine: One 980 hp SFA-built Bristol Mercury XXIV nine-cylinder air-cooled
Performance: Maximum speed 205 mph at sea level, 219 mph at 6250
feet. Cruising speed 186 mph. Landing speed 66 mph. Initial climb
rate 1430 feet per minute. An altitude of 9845 feet could be attained
in 8 minutes. Service ceiling 22,475 feet, Normal range 932 miles,
Maximum range 1380 miles.
Dimensions: Wingspan 47 feet 9 inches, Length 31 feet 9 7/8 inches,
Height 12 feet 4 inches, Wing area 363.2 square feet.
Weights: 5368 pounds empty, 7496 pounds loaded.
Armament: Four wing-mounted 0.30-inch machine guns, plus one flexible
0.30-inch machine gun operated by rear cockpit gunner. Normal bomb
load was typically 20 internally-carried 30-lb bombs and four external
100-lb bombs. Maximum bomb load was 1200 pounds.