Airspeed / Mach Speed Indicator, 80-850 Knots, 0.4-2.5 Mach, F-8 Crusader H-21 This is an authentic WW2

This is an authentic WW2 vintage Dual Engine Synchroscope Indicator made by Kollsman

Here is an Flight Helmet made by Gentex

The manual reviews aircraft engine performance and the effects of different fuels and fuel characteristics

Being partially a gyro instrument it has

The specifics of the modifications is not known

Airspeed / Mach Speed Indicator, 80-850 Knots, 0.4-2.5 Mach, F-8 Crusader H-21 This is an authentic WW2This is an Air Speed Mach Speed Indicator as used in the Viet Nam War era US Navy Fighter Vought F 8 Crusader. Made by Bendix, part number 1454 62A B62 1. See photo of indicator on the F 8 panel from its flight manual dated Sept 1978. The indicator displayed airspeed from 80 850 knots, and mach speed from 0. 4 to 2. 5 mach. Airspeed is displayed from 80 200 knots on the scale from 1 4 o'clock, and then from 80+ knots on the center inner scale window