Longer helicopter fights lag the server.

Hello. I have problem on my server that longer helicopter fights (More Heli HP) lags my server a lot. I've tested that on empty server with flat map and only 1 plugin to increase Heli HP and here you have my fps logs from every 2 seconds:

5759 FPS
5833 FPS
5985 FPS
ThePitereq[76561############] spawned "patrolhelicopter[12865]" at (-181.2, 3.0, -201.7)
[COMMENT] Spawn Heli (-1000FPS)
4980 FPS
4991 FPS
4955 FPS
4956 FPS
4945 FPS
4911 FPS
4893 FPS
5056 FPS
4967 FPS
4945 FPS
4864 FPS
4859 FPS
4507 FPS
4730 FPS
5065 FPS
4926 FPS
5091 FPS
5017 FPS
5018 FPS
[COMMENT] Starting shooting to heli
4858 FPS
4418 FPS
4373 FPS
3749 FPS
3590 FPS
4127 FPS
3900 FPS
4829 FPS
3975 FPS
3501 FPS
3606 FPS
3325 FPS
3291 FPS
3694 FPS
3240 FPS
4142 FPS
4254 FPS
2966 FPS
2964 FPS
2865 FPS
2674 FPS
2586 FPS
1927 FPS
2381 FPS
3107 FPS
3634 FPS
2840 FPS
2521 FPS
2609 FPS
2415 FPS
2347 FPS
2343 FPS
3952 FPS
3993 FPS
3823 FPS
2059 FPS
2040 FPS
2053 FPS
2910 FPS
2023 FPS
3584 FPS
3567 FPS
1859 FPS
1679 FPS
1824 FPS
2976 FPS
2977 FPS
2622 FPS
1678 FPS
1680 FPS
1715 FPS
1710 FPS
1721 FPS
2585 FPS
3292 FPS
3314 FPS
1504 FPS
1643 FPS
1715 FPS
1696 FPS
1699 FPS
1692 FPS
1763 FPS
1723 FPS
1154 FPS
1131 FPS
1557 FPS
1650 FPS
1566 FPS
1494 FPS
1038 FPS
1080 FPS
1609 FPS
1605 FPS
1572 FPS
1529 FPS
2950 FPS
2930 FPS
2841 FPS
1358 FPS
1333 FPS
1344 FPS
1353 FPS
1253 FPS
1482 FPS
1282 FPS
847 FPS
848 FPS
1260 FPS
1255 FPS
1230 FPS
1217 FPS
2054 FPS
2576 FPS
2587 FPS
1184 FPS
1179 FPS
1173 FPS
1169 FPS
1599 FPS
1142 FPS
1106 FPS
1111 FPS
1113 FPS
1133 FPS
1114 FPS
1109 FPS
2344 FPS
2450 FPS
1803 FPS
1043 FPS
1038 FPS
2338 FPS
[ENTCMD] ThePitereq/76561############ used *kill* on ent: assets/prefabs/npc/patrol helicopter/patrolhelicopter.prefab
2174 FPS
[COMMENT] Deleting heli (+5000FPS)
6985 FPS
6860 FPS
6847 FPS
6892 FPS
6810 FPS
6820 FPS
6908 FPS
6966 FPS
7088 FPS
7089 FPS
6741 FPS

Anyone know solution for that? On my main server when player fight the heli for 10-15 minutes the fps goes down to 20-40, so not funny. With every minute of fight the fps goes down.

does this also happen on normal limited fps?