After DEV-update in 28th day or few days before that, AI choppers refuse to land when using LAND-command (land "get in") while "transport unload"-waypoint still seem to work. Issue is only in the DEV-version, wasnt included in the newest official build.
Someone also mentioned seeing similiar issues in Zeus. {F23891}
Check the repro mission, the player is put in spawned chopper (Chop 1) and using test.sqf script with (land "get in")-command to land on spawned helipad. The middle chopper (Chop 2), that is not spawned, is also using the script (in his init-field). Third one is just using the TR-waypoint.
Once the LAND-command is reached the choppers begin to circle around the helipad very violently.
Have been using the same code from ArmA2 days and was always working.
Chop 2 code
http://pastebin.com/YXcwvzZ3
Chop 1 code
http://pastebin.com/DJrYk1V7