Aircraft Recognition Manual, German for RAF Aircraft, "Britische Flugzeuge Erkennungshandbuch" A-26 The permanent magnetic speed indicator

The permanent magnetic speed indicator contains a fixed permanent magnet

This is a WWII-era Accelerometer AN-5475 aka Type B-3 as used in aircraft of the US Army Air Force such as in versions of the Boeing B-17

000 ft to align with the line markings outside of the window

with a year of manufacture of 1945

The third APA-44 model was installed in a B-17 and employed with a new Western Electric search radar

Aircraft Recognition Manual, German for RAF Aircraft, "Britische Flugzeuge Erkennungshandbuch" A-26 The permanent magnetic speed indicatorHere is an authentic WWII era German Recognition Manual for Aircraft of the British Royal Air Force. The manual contains photos and silhouettes of 30 primary aircraft of the RAF in operation during the war. Each aircraft is described using 4 of 64 pages, including its key dimensions and armament. It appears to be early WWII as it includes some pre war RAF aircraft which were obsolete quickly and not later aircraft, as well as only early war US