The poor schmuck who spills his coffee during Maverick's flyby is in the tower at Mirimar. In a dire emergency Maverick is sent back to his carrier after graduation, which is presumably no more than a few weeks after his graduation from Top Gun. Yet when Maverick performs his flyby of the carrier, the same poor schmuck has also returned to the carrier (which has remained deployed all this time) so as to spill his coffee again. Not likely.