So yeah, my random browsing of the tactical gamers forum threw this in my face
(
http://www.jcove-lite.co.uk/)
now then as many of you may know I basically bum off the ArmA series (And original Flashpoint game) and this is a free version of VBS2
.
For those that don't know VBS2 is a military training simulator derived from the ArmA series, and even though it's not a game per say, it can still be bucket loads of fun. It comes with a Mission Editor and every piece of British Army kit you can think of (minus the Eurofighter for some reason).
But yeah it's Free, so you should take a look at it
the mission editor is unbelievably flexible, any operation you can think of you could do.