7 Hunter F.6s of 4 Sqn start up together leaving the familiar AVPIN starter fuel cloud of blue smoke on a very wet day.   Viewed from 4 Sqn Ops Verandah with the alert loudspeakers on the end of the Hangar Tower.   The GCA radar over the top of the first Hunter, was positioned on this side of the airfield and this depended on which runway was in use 10 or 28.   (Thanks to Pete Jennings)