Beam Approach Visual Indicator Ref 10Q/4 RAF A-30 most likely for the benefit

most likely for the benefit of the installers

The manual covers instruments that were eventually used in aircraft of the Air Corps US Army and Air Force US Army during WWII

and EC-121 aircraft

It was installed at the navigators station

the A-20 Havoc

Beam Approach Visual Indicator Ref 10Q/4 RAF A-30 most likely for the benefitThis 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