Watching air crash investigations, and aware of problems with batteries, the issue of fire and sparking is recurrent. As a noble gas 100% Helium would not burn, and if I understand correctly would reduce though not necessarily eliminate sparks. While any additional lift would be marginal, it would likely be sufficient to compensate for the materials necessary to ensure a sufficiently sealed envelope.

So... Has anyone considered filling aircraft voids with Helium?

Watching air crash investigations, and aware of problems with batteries, the issue of fire and sparking is recurrent. As a noble gas, pure helium would not burn, and if I understand correctly would reduce though not necessarily eliminate sparks. While any additional lift would be marginal, it would likely be sufficient to compensate for the materials necessary to ensure a sufficiently sealed envelope.

So... Has anyone considered filling aircraft voids with helium?