The airstairs can be used by selecting the model with airstairs from the
Select an Aircraft menu in FS9 after selecting the PMDG 737 series. To
operate the stairs the following key assignments will need to be made in
FS9. Stairs are extended by using the “Extend Concord Nose Fully”
command and Retracted by using the “Retract Concord Nose Fully” command.
Users will need to create key assignments for these in the FS9
Settings/ Assignments menu and recall them when the stairs are to be