The CF-100 Mk 4 replaced the smooth nose of its predecessors with a more bulbous one housing a Hughes MG-2 fire control system and PG-40 airborne gun-laying radar
in place of the Mark 3's APG-33.
As the radar-countermeasures officer for the 15th AF, I was involved in developing some procedures and equipment to confuse the German Wurzburg gun-laying radar
so it wouldn't be accurate.
There were at least two good reasons why this would be the best place to do it -- the most important being that the chaff loaded into our -D2 was for self-protection against a possible lock-on by the gun-laying radar
of a MiG, and I certainly didn't wan t to deplete it before we were homeward bound.
A study about the Japanese Air Defense System was forwarded to V Bomber Command and 91st Reconnaissance Wing (parent unit of the 20thReconnaissance Squadron) for study and use by bombers, ferrets and "Radar Busters." Additional reports were also available, including one from the HQ AAF Pacific Ocean Area Countermeasures Air Analysis Center titled "The Jamming of Gun-Laying Radars
by the XXI Bomber Command" that outlined formations and jamming techniques.