Back in the day the global layer used to be modified with an "empty land" facility to keep trees from generating too close to the approach line to runways.

Recently I've had a couple of stock single runways that have suffered from this problem. I have increased the groundplane in the airbase facility file to try to address this.

It appears to me, after a bit of testing, that this increases the clear area before the runway, quickly and easily. Has anyone tried increasing the ground plane in the airbase facility files? If it works it is an easy solution rather than fiddling about with empty land facilities in the GL.