foggy cockpit

Always fun to see this phenomena when boarding a regional jet - the fog/mist is often discharged at floor level, so it either gives a whole, "OMG where's the fire" vibe, or more frequently (for me), a "now entering the stage" show appeal. 

It is coming from vents on instrument panel.  Yeah modern military aircraft have AC, simply bleed off a little hot air after compressor.  let it expand.  In high humity, like bases in texas, fog often comes out of vents until about after takeoff.

    It isn't coming from the instuments, in hot climates the onboard air conditioning blows thru vents that are used to defrost the windscreen. What you are seeing is condensation caused by rapid change in pressure and temperature when the canopy is opened.

I'm sorry...say what???