Power Venturi Tube, Double Throat, AN5807-1, Type B-4A Short Stirling The clock itself measures ~3

The clock itself measures ~3

This is a De-Icing Pressure Indicator for the de-icing system used in WWII US Army Air Forces aircraft such as the B-17 Flying Fortress

De Florez championed the use of "synthetic training devices" and urged the Navy to undertake development of such devices to increase readiness

This edition contains a misprint of pages 201-239 covering about 10 pages of the Scintilla chapter and most of the Friez test/recording instruments chapter

and post WWII

Power Venturi Tube, Double Throat, AN5807-1, Type B-4A Short Stirling The clock itself measures ~3This is a nice specimen of the Double Throat Power Venturi Tube used across US military aircraft of the US Army Air Corps Force and US Navy before, during, and post WWII. Made by Sperry, part number 640600. Power venturi tubes provide a source of vacuum for the operation of air driven instruments such as directional gyros, gyro horizons, and turn and bank indicators. The venturi is a tube shaped like a double "V" and has a small opening, called a