Tachometer, Chronometric, Type C-9A, WWII Ki-100 Aichi E16A Type 2 Reconnaissance

Aichi E16A Type 2 Reconnaissance Seaplane Zuiun aka "Paul"

Mounting MT-274/ARN-6

and the gauge measured each engine's crankshaft torque by measuring oil pressure in the engine planetary gear drive system

and its serial number prefix is AC-42

used to calibrate the compass

Tachometer, Chronometric, Type C-9A, WWII Ki-100 Aichi E16A Type 2 ReconnaissanceHere is an exceptional example of the WWII era Chronometric (i. e. mechanical) Tachometer, Type C 9A, as used by single engine aircraft of the Air Corps US Army. According to the US Army Air Force Maintenance Interchangeability Chart dated Feb 1945, the C 9A tachometer was used in fighters P 40 Warhawk (E N), early versions of the P 47 Thunderbolt, and P 51 Mustang, dive bombers A 35 Vengeance and A 36 Apache, and transports UC 61 and UC 64A. This