I am glad that sort of (Lima Site) grass airstrip found its way to SGD's terrains. The one I always hoped to find is rather more bush or dirt airstrip, very narrow, short, surrounded by bushes and trees, not much maintained, only suitable for STOL planes and players piloting such a plane. I managed to create a few on the Khe Sanh map just using Environmental's object delete module and my own addon, a simple set of textures. The problem is the very bumpy nature of the ground in the locations I found suitable on the N and NW edge of the map. Perhaps you find it appealing enough to do some small corrections to the terrain mesh? I'm not asking you for making those LS there, just a little leveling (equalization) of the ground. Landing up or downslope is fine if there's no bumpy ground that limits the length of an airstrip.
The general coordinates are: 1) X1721 Y13384; 2)X6111 Y14658; 3) X11215 Y13990
Here are some screenies taken from those locations:
And this is a movie recorded to show you a ride with a landing on the second of the "improvised" Lima Sites: