Originally Posted by
suninmyeyes
We tried this in a 777 full motion sim a few days ago with altitude in the MCP set to 0000 to see if we could recreate it.
On the take off roll the FMAs read THR TOGA TOGA as usual.
We rotated to 14 degrees. The flight director was giving appropriate pitch demand during rotation and until just after lift off.
FMAs changed to THR LNAV ALT just after it got airborne.
The autopilot was engaged at 100' AGL, Normally it would be at 200 feet minimum but we were interested to see if automatics would make it worse.
With ALT engaged we would have expected the flight director demands to give a descent and take the plane down towards 0000. However it didn't.
After Alt capture It lowered the nose to about 7 degrees pitch up. This resulted in rapid acceleration and approached flap limiting speeds. However the flaps retracted just in time so THR remained constant.
During acceleration to flap up speed the plane climbed at about 300 feet per minute and reached 1100 feet and stayed there and did not descend or climb. It just stayed at 1100 feet in Alt Capture despite the 0000 in the MCP window.
So interesting and slightly different to what I would have expected. This was done at max landing weight so would have been much lighter than the real event.
What I’m interested in, what did the GPWS do during all of this?