A NASA T-38 was making a brief visit to Boeing Field.  It was due in during the afternoon with a planned departure early on Sunday morning.  I was in place in plenty of time for the arrival and got it as it landed.  I went back for the morning departure and gave myself a little buffer in the schedule just in case they were prompt.  They were more than prompt and were airborne quite a while before I got there.  As it turned out, the trip wasn’t a waste, but I was rather frustrated at the time!