Hi Dave,
In the RAF_Collection\Scenery folder, you'll find a bunch of files called Statics_FS...<airfield name>.BGL
If you just change the .BGL to something else (eg .OLD or .OFF or .OFFBGL ...) then it will disable the static aircraft for the airfield you want. Rename back to BGL to re-enable the statics.
Let me know if you have any problems.
Regards,
Iain M.