Airspeed Instrument, Soviet/Russian, Unknown function, Cold War-era F-94 Here is a dual Tachometer

Here is a dual Tachometer for use in military helicopters

dated Oct 29

made by Spencer Lens Co

such as medium bombers B-25 Mitchell

It is in excellent condition given its age

Airspeed Instrument, Soviet/Russian, Unknown function, Cold War-era F-94 Here is a dual TachometerThis Soviet Russian aircraft instrument appears to be for setting an airspeed between 70 220 kilometers per hour. The center knob turns and rotates the only pointer around the dial. The seemingly pitotstatic pneumatic connections in the back are protected by a beige tube for storage (I'm assuming), and an electrical connector exits the back case. It may be some sort of a stall warning instrument, whereby the pilot could set an airspeed below which a