Chevvron,when I was an ATCO at Eastern Radar(civil) in 1983,I was called into the bosses office one day (HL,you may know him).I was given a brown A4 envelope,and told to read the type-written page inside,digest the information,hand it back,and then talk about it to no-one.It contained information about the procedures to be followed when the SR71 was to be operating from Mildenhall during my next morning duty.However,when I arrived for work on the said day,my colleague(DW,whom you may also know,being an ex-ATCA).had already arrived,and had 'plugged-in'.Bearing in mind my instructions,I said nothing to him,presuming he had been shown the contents of the aforementioned brown envelope.I did however watch the progress on the spare screen,and thereafter these flights were quite a common occurrence,but I do wonder if this was the first one.