Kerbal Space Program

I was intentionally performing part.explode approx 3km above KSC on a test vessel. A single LY-05 wheel was attached. This NullRef occurred when the wheel collided with the terrain. I was able to reproduce this result by again, exploding a part on a vessel and waiting for the debris to fall to the surface.

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[LOG 16:16:51.948] probeStackSmall Exploded!! - blast awesomeness: 0
[LOG 16:16:51.952] [probeStackSmall]: Deactivated
[LOG 16:16:51.952] [F: 16928]: [GearFree] Collision Enhancer Punch Through - vel: 65.38129
[LOG 16:16:51.967] 1 explosions created.
[LOG 16:16:54.604] Untitled Space Craft Rover Probe Debris Unloaded
[LOG 16:16:54.605] Packing Untitled Space Craft Rover Probe Debris for orbit
[ERR 16:16:54.608] Can't remove Rigidbody because KSPWheelController (Script) depends on it

[EXC 16:16:54.637] NullReferenceException
VPWheelCollider.GetGroundHit (UnityEngine.WheelHit& hit)
VehiclePhysics.VehicleBase.CalculateSuspensionTravel (VehiclePhysics.WheelState wheel)
VehiclePhysics.VehicleBase.FixedUpdate ()
[EXC 16:16:54.639] NullReferenceException
UnityEngine.Transform.get_rotation ()
UnityEngine.Transform.get_up ()
VPWheelCollider.FixSteerAngle (Single inputSteerAngle)
VPWheelCollider.set_steerAngle (Single value)
VehiclePhysics.VehicleBase.Update ()
[EXC 16:16:54.657] NullReferenceException
VPWheelCollider.GetGroundHit (UnityEngine.WheelHit& hit)
VehiclePhysics.VehicleBase.CalculateSuspensionTravel (VehiclePhysics.WheelState wheel)
VehiclePhysics.VehicleBase.FixedUpdate ()
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