Beam Approach Visual Indicator Ref 10Q/4 RAF A-30 This is a fine example

This is a fine example of the electrical Fl

BU AERO USNAVY is embossed on its face

the A-20 Havoc

most likely for the benefit of the installers

Judging from the accompanying instructions

Beam Approach Visual Indicator Ref 10Q/4 RAF A-30 This is a fine exampleThis is a WWII and Cold War era Beam Approach Visual Indicator, Ref 10Q 4, Mod 27 as used in bomber aircraft of the Royal Air Force such as the Avro Lancaster (see illustration of the Lancaster instrument panel from the Pilots Notes showing the location of the indicator). Per the Rochester Avionics Archives: The Standard Beam Approach System is similar to the ILS system used in Modern aircraft. Beam Approach Beacon System BABS was a homing device used