Getting familiar with the subject so I might be missing something crucial.
This Geometry Collection simulates physics but is not affected by gravity:
I slam the actors into the ground 
, the smaller chunks break off and fly away convincingly:
However, the large chunks that did not fully fracture are now affected by gravity all of a sudden.
- is this intended?
- is this a bug?
I was expecting the large chunks to remain unaffected by gravity. Note this only manifests if the collection breaks. If the damage threshold is not exceeded, the component remains floaty, indeed.
Zeroing Default Gravity Z in the Project Settings does fix the issue, but that’s a global setting. UE v5.5.1
Apologies for tagging you in @CedUE but you’ve been an invaluable source of insight.