Airborne Interphone/Radio Jack Box, BC-334 US Army Air Force BT-14

Airborne Interphone/Radio Jack Box, BC-334 US Army Air Force BT-14The BC 366 Jack Box was part of the RC 26, RC 27, and RC 35 Interphone Systems, used to control airborne communications of the aircraft interphone and radio during flight and on the ground. The BC 334 Jack Box was commonly used across two seat aircraft of the US Army Air Force and US Navy such as trainers AT 6 Texan and BT 13 Valiant. See photo from the 1945 AT 6 Erection and Maintenance Manual showing the position of a BC 366 at the pilots side. This

as used in military helicopters of the USSR and Poland such as the MIL MI-1 (see cockpit photo

the B-50 Superfortress Bomber dated 1956

See photos of its placement at the navigators station in the Avro Shackleton and Canberra

hard to discern

Its an interesting indicator nonetheless

The knob is used to set the dial to match engine RPM

but it could be cemented in place

with indicator pointed out

The indicator marked for engines 1 & 2 was made by Ranco with a 1943 manufacturing serial number prefix

Sweeting’s book "Combat Flying Equipment":

Included is a clear cover

Weston model 301