F9 option from comms menu (Engage Primary and Rejoin) mission 5

[Aitch5]

Minor issue but in mission 5 I am unable to command 2nd element or flight to "engage primary and rejoin" - pressing F9 seems to freeze the view (pressing F9 again unfreezes).  The work around is F10 "engage primary and RTB" (which works) and then commanding "rejoin" once primary target has been destroyed.  Using Headtracker IR and UK keyboard.

[Reflected]

As stated in the campaign doc pdf as well as the on screen message in mission 4, you control your flight with the built in menu and the 2nd flight with the F10 menu.