First rumors about the incident at MEX...
Ground personnel removed cargo from the forward hold before offloading the main deck - basically loaded with flowers from GYE, the previous stop - and the aft hold. Pilots noticed something wrong when they tried to set up the FMS prior to departure because several alerts appeared related to the ground sensor - caused due to the initial movement of the nose gear, slightly off the ground. However after removing the last pallet from the fwd cargo an abrupt pitch up occurred.
That MD-11F (registration:
PR-LGE) has a ground fuel loading schedule ratio (7.5:1) however this fuel distribution to the tail tank only occurs when the refueling panel door on the wing is closed and total fuel in the tanks is greater than 70 tons ... anyway, this is not the case because next destination was LAX and required fuel is well below that number.
There are several recommendations for loading/offloading procedures and there is a higher chance for a tail tipping in case of less than 3000 kg in the forward cargo hold, heavy cargo located on the position H (approximately at STA 1420) and beyond, more than 10 tons of total fuel in the main tanks and etc.