Reproduced 3/3 times. Issue does not occur in //UE4/Release-4.27, so Confirmed Regression.

Steps to Reproduce
  1. Create and open a new Character Blueprint
  2. Add a Scene Component
  3. Attach a Skeletal Mesh to the Scene Component (and not by assigning a mesh). The mesh must be capable of something like ragdoll hair.
  4. In Event Graph, Connect BeginPlay to "Set All Bodies Below Simulate Physics." Set New Simulate as True and Include Self as false.
  5. Use Make Literal Name to assign In Bone Name to the root of the Skeletal Mesh
  6. Create a Loop that uses Set Actor Location to move ~1000 away from the starting point and back. Enable Teleport.
  7. Add Character Blueprint to level & PIE

Actual Result: Hair is seemingly stretched and dragged back and forth due to physics velocity updating

Expected Result: Hair physics velocity should not update (compare this to an Actor Blueprint that uses the same repro steps)

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ComponentUE - Simulation - Physics - Character
Affects Versions5.1
Target Fix5.4
CreatedNov 28, 2022
UpdatedOct 26, 2023