Tex,
simply put you werent far enough away from the nearest enemy! Doesnt matter where you are on the map, except if you happen to find some concrete to tower out on, if you tower out and an enemy is within the range you get a ditch.
Judging from your account it's likely the B24 was too close,but as Lusche pointed out an unseen enemy GV could cause the same thing. If you really are concerned about a successful landing the best bet is to find some concrete in friendly territory and tower out there. Of course a friendly storch or other A/C could scout the area to see if you're clear but otherwise be prepared for a long drive home!
It's similar to landing a plane,if you have just 1 wheel off the tarmac it's a ditch, the line has to be drawn somewhere and I think HTC is rather generous with the "line" for GV's.
If you'd like we can talk about it,just drop by you know where to find me!