Emergency hyperspace seal

Emergency hyperspace seals were plastisteel seals that protected cargo bay doors while traveling through hyperspace. When a ship would enter hyperspace, the seals would automatically extend over the vessel's large hatches, staying in place until the ship exited hyperspace, at which point they would retract. The emergency seals were not load-bearing, they would merely provide a better carrier surface for the hyperfield. If cargo bay doors were to be opened before reverting to realspace, the pressure differential between hyperspace and realspace would shatter the seals and the contents of the hold would be sucked out into the vacuum.

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