I thought there was a universal switch to set all AC to 90 degrees. Maybe in the config menu?
Edit:
Here …. x:\Falcon BMS 4.33 U1\User\Config\falcon bms.cfg
set g_fViewlimitPitchDown 90.0 // Overrides all A/C viewlimit_pitch_down values from the 3dckpit.dat files, max. 90.0, only higher values take effect
File can be opened and edited with any plain text editor (like Notepad).