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.