I read the early pages of this thread some time ago, came back to the thread today. Could not be bothered with the intervening pages, no doubt much of the same. Found the early pages depressing in that almost all contributors knew little about flying and clearly f...al about the the 747, despite quoting a "747 pilot says" his quoted sayings being mainly rubbish.
Tailstrikes are almost unknown on T/O, a possible hazard on landing if one is not careful with the AOA (means Angle of Attack or Pitch Attitude for many contributors who lack this this basic knowledge) on landing above 12 degrees is really pushing your luck. .
Boeing at the bequest of BA designed an over- rotation warning for TO, installed nowhere else and later abandoned
Now I see people drawing maps on this thread. The Canadian Accident investigators are internationally acknowledeged as being amongst the best in the world. Just wait for their report, meanwhile don't embarrass yourself by trying by guess the out come
If I was sober, I could go on for hours, but trying to type accurately is becoming tedious.
It is threads like this, and there are many of them, that make PPrune look faintly ridiculous.
Some time ago there was a pompous thread, with which at the time I did not agree, that said make this forum for real airline professional pilots only. I now think that maybe he had a point.
Time for bed for me.
rockhound
The dimensions of the 747 undercarriage are laid out on the dimensions page of the AFM.