In a character's Physics Asset, a bone that is set to Kinematic and its children will have a scale of 1 overriding the Skeletal Mesh's Scale Transform settings. When the root of the body is changed to Kinematic, the scale is not changed back to 1. 

Reported in version 4.25.3(CL 13942748). Tested and found in versions 4.25.3 and 4.24.3(CL 11590370). 

Steps to Reproduce
  1. Create a 3rd Person Template Project.
  2. Open SK_Mannequin_PhysicsAsset.
  3. Change the upperarm_r to Kinematic.
  4. Place the skeletal mesh in level.
  5. Scale the skeletal mesh to 0.75, 0.75,0.75.
  6. Set Simulate Physics.
  7. Notice that upperarm_r and all children bones are scaled back to 1. Be aware, it will fly around. Immediately pausing the PIE will help.
  8. Change pelvis to Kinematic.
  9. Notice that the scale wont override.

Result: Bone's world scale in level is overridden and set to 1 if it is Kinematic in Physics Asset. But not overridden if root bone is kinematic too.

Expectation: Bone's scale shouldn't be overridden in level.

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Won't Fix
ComponentUE - Simulation - Physics
Affects Versions4.
CreatedOct 7, 2020
ResolvedJul 19, 2022
UpdatedJul 19, 2022