There absolutely are ways to make a trip down safer than sticking people in an improperly engineered carbon fiber tube with (apparently) no metal liner; they used the wrong lay-up techniques for sure and there was no cross-lay - only simple spooling over a metal form. That thing wasn’t even as safe as a commercial diving gas cylinder.
1. Testing…. Common testing standards for a pressure vessel don't appear to have been used. Apparently, destructive testing was not performed to validate the carbon fiber pressure vessel's manufacturing technique versus the required external pressure nor the effect of pressure cycling on material fatigue over time. Instead, a novel ultrasonic technique was substituted to save costs.
So…. To save big $$$ and time, a corner was cut. This is why a conditional experimental certification was issued instead of a type license. Unknowns remained unknown.
2. I've read that the Titanic depth was about 1000-2000 feet deeper than the maximum operating depth certified by the experimental license. If this is correct, why wasn't the experimental operating license jerked?
In addition, there was a wink wink nod nod involved via the experimental license in that the sub was not carrying “passengers” on a for hire basis but “researchers” doing scientific work.
In a similar vein, I have read that the titanium endcap and ring with the viewing port was manufacturer certified to a much lower operating depth that was way shallower than the Titanic depth. Criminal negligence IMHO if correct.
3. The control systems seems sketchy from from what I've read. No reason to be sketchy for this. Controllers are off the shelf in rugged industrial gear that can be configured to have multiple backups. Cheapskate idiots…
I've rambled more than enough…. Simple opinions... Nothing more…