Category A Flight/Airspace ?
Was operating out of LHR this evening, when a RAF Sea King arrived at the Royal Suite. It departed several minutes later with its 'precious' cargo. 40 minutes start delays then ensued as LHR basically closed to allow it right of passage. Delivery mentioned 'Category A Flight' and at least one femail controller got her knickers in a twist when asked about it. Can anyone shed any light on this incident and please let me know what a Cat A flight is? Is it like purple airspace?
Cheers
Sean D