In 1934, the Belgian Air Force drew up a specification for a multi-purpose bomber and long-range reconnaissance aircraft, which could also act as a heavy fighter. To meet this requirement, designs were produced by Les Ateliers de Constructions Aéronautiques Belges (LACAB) and by Stampe et Vertongen (the Stampe SV-10).
The LACAB design was a twin-engined biplane of mixed construction, with a slab-sided steel tube fuselage with plywood and fabric covering and wooden, two-bay unequal span wings. It was powered by two Gnome-Rhône Mistral Major radial engines mounted between the wings, and was fitted with a fixed tailwheel undercarriage.
Manually operated gun turrets, each mounting two machine guns, were mounted in nose and dorsal positions, while two more guns were in a ventral position.
The sole prototype first flew on 14 May 1936 and was handed over to the Belgian Air Force for testing on 2 July 1936. The Spanish Republican Air Force attempted to buy the prototype LACAB GR.8, but the international arms embargo prevented delivery to Spain.
The prototype was badly damaged in a landing accident on 4 April 1938 with its undercarriage and starboard wings destroyed. Although the aircraft was repaired, it was not flown again, and no production was undertaken. The GR.8 was scrapped after the German invasion of Belgium in May 1940.