As I recall, one of the mandatory Instrument Rating items for Vulcan pilots was a 45° steep turn at M0.84 and FL410...
I've been above FL500 at well over 45° AoB watching F-4s vainly trying to achieve a missile solution. During a trip to CFB Chatham, after the F-101 had 'fired' its rather unsporting Genie, in the visual merge we ended up tracking him happily in his 6 o' clock. The tape they played afterwards was hilarious "How did you let something that big get behind us?" was the radar observer's comment!