Following code works as a workaround

	void FClusterUnionManager::HandleAddOperation(FClusterUnionIndex ClusterIndex, const TArray<FPBDRigidParticleHandle*>& Particles, bool bReleaseClustersFirst)
		if (bIsNewCluster)
			if (bIsSleeping)
				MEvolution.SetParticleObjectState(Cluster->InternalCluster, Chaos::EObjectStateType::Sleeping);

			MEvolution.SetPhysicsMaterial(Cluster->InternalCluster, MEvolution.GetPhysicsMaterial(FinalParticlesToAdd[0]));
			Cluster->InternalCluster->SetControlFlags(FinalParticlesToAdd[0]->ControlFlags() );  // add this line to copy gravity setting
			Cluster->InternalCluster->SetLinearEtherDrag(FinalParticlesToAdd[0]->LinearEtherDrag() ); 
			Cluster->InternalCluster->SetAngularEtherDrag(FinalParticlesToAdd[0]->AngularEtherDrag() ); 

Steps to Reproduce
  1. Download the repro project from the link in the AdditionalInfoURL
  2. Build and launch the repro project
  3. Start PIE
  4. Observe the rigid bodies falls slowly
    Note : the rigid bodies have custom gravity setup
  5. End PIE
  6. Select 2 `Cube_GeometryCollection`s
  7. Set ClusterGroupIndex to 1 in detail pane
  8. Start PIE


Clustered rigid body ignores custom gravity settings in children and fall with default gravity

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ComponentUE - Simulation - Physics
Affects Versions5.3
Target Fix5.5
CreatedMar 7, 2024
UpdatedMar 13, 2024