They copied the glass fiber + titanium rings idea from the Deepflight Challenger that Virgin wanted to dive with. [0] Virgin deemed the design not safe enough

They copied the glass fiber + titanium rings idea from the Deepflight Challenger that Virgin wanted to dive with. [0] Virgin deemed the design not safe enough for more than a single dive and quietly scrapped the diving events: "Based on testing at high pressure, the DeepFlight Challenger was determined to be suitable only for a single dive, not the repeated uses that had been planned as part of Virgin Oceanic service." [1] [0] https://www.compositesworld.com/articles/composite-submersibles-under-pressure-in-deep-deep-waters https://www.compositesworld.com/articles/composite-submersib... [1] https://en.wikipedia.org/wiki/DeepFlight_Challenger https://en.wikipedia.org/wiki/DeepFlight_Challenger