A quad 20mm gunpack was built and ground and air tested using the T160 20mm revolver cannon.
The program started November of 1952 and ended April 22, 1955. There were too many problems
with the T160 so the project was dropped. On one flight it wasn't the issues with the gun construction
that caused problems, during the firing test parts of the engine cowlings came loose and departed the airframe.
Above from Larry Milberry, The Avro CF-100
The T160 was developed into the M39 cannon and is still in use, so I have to wonder if, rather than
the official line Milberry quotes that the problem was the gun, the real problem was in the structure of
the Clunk? Perhaps it simply couldn't take the vibration and pounding of firing a multi-cannon
armament? The Clunk had structural problems right from the beginning, so I wonder if the fixes
were not as complete as claimed? Also they had some serious difficulties in getting the eight .50-cal
gun pack to work properly.
BTW in the book Milberry reproduces sections of a January 1956 Avro document that discusses
why the collision course unguided rocket attack was better than a gun attack. The upshot was
that the rockets could be used for automatic, all-around blind attacks, whereas a guns only blind
attack could only be made from astern where the attacking aircraft was in the most danger from
the bomber's defensive radar and guns. Plus you have the big negative of being in a stern chase.
It also states that the clustered rockets were only a temporary solution while awaiting development
of functional guided missiles.
