At the end of the day, you are taking a ride on public transport. So when I get changed I do so behind closed and locked doors and as they generally won't evacuate the cockpit (pun intended) for me, it has to be the lavatory/bathroom/restroom/loo etc.

I do not get changed until we have reached cruising altitude or are at least a good way towards it. Not only is there the whole deplaning thing if the plane goes tech on the ground (or any one of an array of other things that can cause premature reverse boarding preventing pushback) but there's also the possibility of the plane going tech in the air / incomplete takeoff / combined takeoff and landing! The most critical parts of any flight are takeoff and landing. When those are going on I want to be ready for action - and not "commando" style action! That means wearing complete and real clothes (that won't melt on my body if there is a fire in the cabin) and robust footwear so I can scramble under/over/round/through anything or anyone that I need to, and/or perform acts I wouldn't otherwise dream of doing under normal public transportation situations. Safety first. Champagne second. Pajamas Third.

rb211.