Going by what you described, someone seems to have made an half-assed job in manipulating the Flight Dynamics of that B744... if the plane is important to you, you can either put yourself patiently at debugging said FD or you can simply transplant FD from another, working B744.
To do this, locate a surely working B744 (
which FD better be worth being used). Copy into a temp folder its Aircraft.cfg and .AIR files. Open the fictional AFO B744's Aircraft.cfg, find its Contact Points and Lights sections and copy then into the temp folder's Aircraft.CFG, replacing this one's previous similarly named sections and settings.
After having done the above mentioned modification, delete the AFO B744 Aircraft.cfg and .AIR file and copy into its folder the two modded files from the temp folder.
Fire up FS and try your modded AFO B744 out. it
SHOULD work fine.
Let me know.

There is no such a thing as overkill. Only unworthy targets.