AMU: aviation monetary unit = $1,000 U.S. Useage: "That alternator replacement cost me 1.5 AMUs," though it would have cost $300 for a car and $600 for a boat. (Thanks to Kelly Vinton.)
OWTA: One With The Airplane. A state of proficiency where the airplane
does what you wish with little or no interruption by your forebrain. Also
indicates a high degree of sensitivity on the part of the pilot to the state
and health of the airplane. (Thanks to Tim Metzinger)
OWTG One With The Ground. As contrasted with OWTA, this is not a good position for a pilot. It could be the opposite of "keeping the blue side up".
UWOF: Upside-down in the Weeds On Fire (for purists: UDIWOF). A consequence of not being in control of the airplane,particularly if you don't manage your airspeed on final and "force" the airplane to the runway. Acronym created last century by Bob Goodman, an Alabama professor and Mooney pilot, who repeatedly cautioned that this would be the consequence of shoddy maintenance, which would lead to the failure of the "little bitty bolt" which holds the tail on.