Originally Posted by
UAL T38 Phlyer
USMC:
Waterline(s): parallel lines of reference, in inches, more or less parallel to the bottom of the aircraft. The idea being that if the aircraft were placed in water, this would be the resulting line. There will be a Zero reference line; anything above is referenced with "+" so many inches, and those below are "-."
Station: a reference for distance from nose to tail, in inches. Zero is not necessarily on the aircraft...often in front of the nose.
Buttock Line: References left and right of the centerline, in inches.
Yes - in this case then I meant centerline or waterline - same concept. I was also referencing this to the 'waterline' symbol in our HUD showing nose position when the INS derived velocity vector is removed or it is HUD limited.
Station above is the weight and balance term.
Haven't heard buttock line
USMCFLYR