Hello!
During BAT 4.2.2 testing I fixed ground collision of this plane. If you want to collide with ground instead of sinking into ground, then you can replace [Hooks] and [HookLoc] sections of Engine1_D0.msh with these:
[Hooks]
_Engine1EF_01 <BASE>
_Engine1EF_02 <BASE>
_Engine1EF_03 <BASE>
_Engine1EF_04 <BASE>
_Engine1EF_05 <BASE>
_Engine1EF_06 <BASE>
_Engine1EF_07 <BASE>
_Engine1EF_08 <BASE>
_Engine1EF_09 <BASE>
_Engine1EF_10 <BASE>
_Engine1EF_12 <BASE>
_Engine1EF_13 <BASE>
_Engine1ES_01 <BASE>
_Engine1ES_02 <BASE>
_Engine1ES_03 <BASE>
_Engine1ES_04 <BASE>
_Engine1ES_05 <BASE>
_Engine1ES_06 <BASE>
_Engine1ES_07 <BASE>
_Engine1ES_08 <BASE>
_Engine1ES_09 <BASE>
_Engine1ES_10 <BASE>
_Engine1ES_12 <BASE>
_Engine1ES_13 <BASE>
_Engine1Smoke <BASE>
_Clip04 <BASE>
_Clip05 <BASE>
_Clip06 <BASE>
_Clip07 <BASE>
_Clip08 <BASE>
_Clip09 <BASE>
[HookLoc]
-0.109482 -0.250079 0.962016 0.754519 -0.650963 -0.0833525 0.647082 0.716733 0.259958 -0.5163 -0.4907 0.53814
0.534888 -0.233542 0.812006 0.824791 -0.0642185 -0.561779 0.183344 0.970224 0.158274 0.62338 -0.39733 0.53199
-0.109482 -0.101445 0.988799 0.754519 -0.656078 0.0162325 0.647082 0.747844 0.14837 -0.67932 -0.24404 0.53104
0.302476 -0.531924 0.790927 0.953105 0.16012 -0.256812 0.009961 0.831516 0.555412 0.69959 0.21175 0.70513
-0.0844375 -0.524752 0.847057 0.750866 -0.592345 -0.292108 0.655035 0.611362 0.444035 -0.68843 0.22172 0.72068
0.302476 -0.531924 0.790927 0.953105 0.16012 -0.256812 0.009961 0.831516 0.555412 0.69959 0.13041 0.65054
-0.0844375 -0.524752 0.847057 0.750866 -0.592345 -0.292108 0.655035 0.611362 0.444035 -0.7254 0.14344 0.66609
0.302476 -0.531924 0.790927 0.953105 0.16012 -0.256812 0.009961 0.831516 0.555412 0.69959 0.05196 0.59588
-0.0844375 -0.524752 0.847057 0.750866 -0.592345 -0.292108 0.655035 0.611362 0.444035 -0.71871 0.04594 0.61143
0.534888 -0.233542 0.812006 0.824791 -0.0642185 -0.561779 0.183344 0.970224 0.158274 0.55971 -0.46929 0.52342
0.534888 -0.233542 0.812006 0.824791 -0.0642185 -0.561779 0.183344 0.970224 0.158274 0.50391 -0.55881 0.52342
-0.109482 -0.250079 0.962016 0.754519 -0.650963 -0.0833525 0.647082 0.716733 0.259958 -0.46698 -0.57569 0.53574
-0.200619 -0.168882 0.965003 0.735552 -0.676589 0.0345095 0.647082 0.716734 0.259958 -0.50624 -0.48818 0.51157
0.430384 -0.223975 0.874417 0.883829 -0.0922015 -0.458633 0.183345 0.970224 0.158274 0.61577 -0.39011 0.50547
-0.200619 -0.020732 0.97945 0.735552 -0.66355 0.136616 0.647082 0.747844 0.14837 -0.66926 -0.24557 0.50439
0.184067 -0.547473 0.816329 0.982863 0.094101 -0.158508 0.00996125 0.831516 0.555412 0.69913 0.20568 0.70977
-0.175316 -0.448651 0.876343 0.734979 -0.651881 -0.1867 0.655035 0.611362 0.444034 -0.67907 0.22053 0.71888
0.184067 -0.547473 0.816329 0.982863 0.094101 -0.158508 0.00996125 0.831516 0.555412 0.69913 0.12435 0.65518
-0.175316 -0.448651 0.876343 0.734979 -0.651881 -0.1867 0.655035 0.611362 0.444034 -0.71604 0.11742 0.6483
0.184067 -0.547473 0.816329 0.982863 0.094101 -0.158508 0.00996125 0.831516 0.555412 0.69913 0.04589 0.60052
-0.175316 -0.448651 0.876343 0.734979 -0.651881 -0.1867 0.655035 0.611362 0.444034 -0.74074 0.06506 0.59364
0.430384 -0.223975 0.874417 0.883829 -0.0922015 -0.458633 0.183345 0.970224 0.158274 0.5521 -0.46207 0.4969
0.430384 -0.223975 0.874417 0.883829 -0.0922015 -0.458633 0.183345 0.970224 0.158274 0.4963 -0.55159 0.4969
-0.200619 -0.168882 0.965003 0.735552 -0.676589 0.0345095 0.647082 0.716734 0.259958 -0.45693 -0.57316 0.50917
0 0 1 1 0 0 0 1 0 -0.07094 0.59109 0.21617
-1 0 0 0 0 1 0 1 0 0.0 -0.5723 -0.4685
-1 0 0 0 0 1 0 1 0 0.00251 0.62841 -0.4511
-1 0 0 0 0 1 0 1 0 -0.59422 -0.0165 -0.44918
-1 0 0 0 0 1 0 1 0 0.57872 -0.0165 -0.45317
-1 0 0 0 0 1 0 1 0 0.2063 -0.6145 -0.07047
-1 0 0 0 0 1 0 1 0 -0.2063 -0.6145 -0.07047
This bug was caused by missing _Clip04 hook, so all _Clip hooks got ignored except first four in propeller. I've added that missing one and moved others to better positions for proper ground collisions.