TBF-1 Avenger Torpedo Bomber Cruising Calculator Mark 1-A, Ser # 4669-43 Smiths November 1943

November 1943

at 9 x 7 x 4 inches the unit is larger than one might regard a handset

flight instruments

Adapter rings were also available for fitment of either A-1 or A-2 tilting heads for use as a fixed gunnery gunsight on attack and light bomber plane(c)

giving it quite a heft

TBF-1 Avenger Torpedo Bomber Cruising Calculator Mark 1-A, Ser # 4669-43 Smiths November 1943This is an authentic original WWII era Cruising Computer Mark 1 A designed specifically for the US Navy's Grumman Torpedo Bomber TBF 1. The purpose of the calculator was to determine the range, in nautical miles, of the aircraft under various conditions of aircraft weight, head tail winds, fuel quantity on board, true air speed, altitude, and throttle and supercharger blower settings. The calculator is essentially a custom 3 panel slide rule