Originally Posted by
DaveReidUK
Gz is vertical acceleration at the CofG.
To get a picture of what's happening at the back end, you would need to factor in pitch data.
Originally Posted by
RatherBeFlying
Gz in the fdr trace will be measured wherever the accelerometer is located. My guess is that it's located in the avionics bay. An abrupt pitch rate will produce opposing Gz rates at the ends of the aircraft.
Now, we do have 2 different definitions, which one is the correct one ?
Originally Posted by
RatherBeFlying
Once the pitch rate goes to zero, unrestrained objects will tend to continue in the direction they have been accelerated, much like a catapult if in the rear during a pitch down. In front, unrestrained objects in negative Gz will head to the ceiling and drop back down when Gz rate returns to zero, as was demonstrated by an ashtray bouncing off the ceiling when I advised my instructor we were climbing into the path of another airplane on a converging course. He had been questioning my reducing our climb from a practice forced approach.
Yeah, happens with negative g.