I'd like to know how the pilot turned around; i.e., whether he disguised the 180 with a 3-minute 1.2g turn, or perhaps a 4g wingover with a big altitude loss (not likely, of course), and whether he waited for the military escort before doing anything. Such things might telegraph how seriously the pilot understood the situation to be.
HF
I thought Air Marshals had already intervened... the pilot would presumably not need to disguise his actions?
How about a nice split S or Immelman? I bet the aircraft could do it if he dumped some fuel first.
Here's a sound clip of Dutch ground control communications regarding the U.S. Northwest Airlines plane on approach to Schiphol/ Netherlands.
http://fmc.dotnet-services.nl/waves/nw42_intercept.wav