When doing the quests that require my settlers to board the shuttle, once it is supposed to land game drops to 1 fps and the same error is spammed over and over, does not matter if shields are active or un-powered.
There is no problem when shuttle is picking up NPCs instead.
There is no problem if shield generators are destroyed.
Error is the following:

System.NullReferenceException: Object reference not set to an instance of an object
at VFESecurity.Building_Shield.ThreatDisabled (Verse.AI.IAttackTargetSearcher disabledFor) [0x00016] in <0c7cdc35ad2d49599f507a35801f85c4>:0
at RimWorld.DropCellFinder.IsSafeDropSpot (Verse.IntVec3 cell, Verse.Map map, RimWorld.Faction faction, System.Nullable`1[T] size, System.Int32 distToEdge, System.Int32 distToHostiles, System.Int32 distToFires) [0x000e6] in <b64badbf3c3d41018b3ca5d3e8c77771>:0
at RimWorld.DropCellFinder.SkyfallerCanLandAt (Verse.IntVec3 c, Verse.Map map, Verse.IntVec2 size, RimWorld.Faction faction) [0x00009] in <b64badbf3c3d41018b3ca5d3e8c77771>:0
at RimWorld.DropCellFinder.TryFindSafeLandingSpotCloseToColony (Verse.Map map, Verse.IntVec2 size, RimWorld.Faction faction, System.Int32 borderWidth) [0x000c4] in <b64badbf3c3d41018b3ca5d3e8c77771>:0
at RimWorld.DropCellFinder.GetBestShuttleLandingSpot (Verse.Map map, RimWorld.Faction factionForFindingSpot, Verse.Thing& firstBlockingThing) [0x00016] in <b64badbf3c3d41018b3ca5d3e8c77771>:0
at RimWorld.DropCellFinder.GetBestShuttleLandingSpot (Verse.Map map, RimWorld.Faction factionForFindingSpot) [0x00000] in <b64badbf3c3d41018b3ca5d3e8c77771>:0
at RimWorld.ShipJob_Arrive.TryStart () [0x0006d] in <b64badbf3c3d41018b3ca5d3e8c77771>:0
at RimWorld.TransportShip.TryGetNextJob () [0x00020] in <b64badbf3c3d41018b3ca5d3e8c77771>:0
at RimWorld.TransportShip.Tick () [0x0001f] in <b64badbf3c3d41018b3ca5d3e8c77771>:0
at RimWorld.TransportShipManager.ShipObjectsTick () [0x0001c] in <b64badbf3c3d41018b3ca5d3e8c77771>:0
at (wrapper dynamic-method) Verse.TickManager.Verse.TickManager.DoSingleTick_Patch1(Verse.TickManager)
UnityEngine.StackTraceUtility:ExtractStackTrace ()
Verse.Log:Error (string)
(wrapper dynamic-method) Verse.TickManager:Verse.TickManager.DoSingleTick_Patch1 (Verse.TickManager)
Verse.TickManager:TickManagerUpdate ()
(wrapper dynamic-method) Verse.Game:Verse.Game.UpdatePlay_Patch2 (Verse.Game)
Verse.Root_Play:Update ()