There are scripts in the Ed Depot for this. You can do it just by telling them to eject, but usually you want the chopper to be in the right place etc etc.
Or just insert a parachute using the editor and moveindriver the loon you want. Or createvehicle I suppose, never tried it.
In other words there's nothing special about black ops when it comes to jumping out of aircraft, any loon can do it.