Mach Speed Indicator (Machmeter), Mk 3A, Ref 6A/3300, RAF Carvair Here is an Altimeter

Here is an Altimeter

FSSC number 88-I-2385-100

This example has been installed in an aircraft during its service life

according to the Maintenance Interchangeability Chart dated Feb 1945

and the knob rotates stiffly

Mach Speed Indicator (Machmeter), Mk 3A, Ref 6A/3300, RAF Carvair Here is an AltimeterThis is a fine example of a Cold War era Mach Speed Indicator Mk 3A Ref 6A 3300, as used in aircraft of the British Royal Air Force. The indicator displays aircraft mach speed from 0. 7 to 1. 3 mach. The serial number indicates a year of manufacture of 1958. The indicator is also marked with K. M. A. 0201K, likely a part number. The RAF Air Ministry arrow emblem is marked on the rear case. The adjustment screw at 6 o'clock position moves a white