Independent of whether carbon fibre was the best choice of materials for this application, and whether layup of layers is the best construction method for this, evidence of delamination demonstrates after only a few cycles suggests poor cleanliness and quality control during layup.
Yes, everything about the slapdash design, incorrect material selection, sloppy construction, lack of adequate testing, and refusal to obtain certification screams unsafe and dangerous. People in the know rejected the entire mess. The CEO had to convince gullible, wealthy individuals to fork over US$250K for a session of undersea Russian roulette.
Carbon fiber is extremely strong in tension. In compression it sucks. There was about 6000 psi of compression on that hull.
That was the thing that jumped out at me.
Delamination.
Kiss of death for carbon fibre composites. Sure death at nearly any significant depth, not even 4,000 meters.
I only know from what I have read regarding use in airliners like the Boeing 787, and being at 40,000 feet altitude is child’s play from a stress perspective from being at 4,000 meters.
Sad. I don’t feel sadness for the men who went down in it, because they made their own calculations and should have known better. That 19 year old guy was different. And his calculations were more emotional than rational.