TBF-1 Avenger Torpedo Bomber Cruising Calculator Mark 1-A, Ser # 5031-43 B-47

TBF-1 Avenger Torpedo Bomber Cruising Calculator Mark 1-A, Ser # 5031-43 B-47This 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

it was also used across other USN aircraft such as the TBM Avenger

used to calibrate the compass

to red/white (stopped)

The dial markings are clear and the glass and cases are intact

The text "AC USARMY" is embossed on its face

Covers celestial and polar navigation

shifts the index line in the small round window at ~19

DC 0-400 Microamps Westinghouse style CH-10533-N3-1 approx 3

who was a maker/distributor of drafting and surveying instruments and supplies

This indicator

The data plate is absent from this example

With a serial # prefix AC44