The B-17 usually formed up abouve the cloud layer (or undercast) using a radio beacon system called "Buncher" or "Splasher". The three plane Vee shape was the basic element of all formation flying but the bumber of Vees in a Squadron/Flight and the number of squadrons in a Group varied as tactics changed over time.


The US 8th Air Force developed this system to allow 36 bombers to form up above the clouds. A 'Buncher' signal was emitted by a radion beacon around which the bombers would circle for an hour while every flight got into the air.