Wreckage of the Titan’s creative carbon fiber hull was set up splitd into three contrastent layers, US National Transportation Safety Board engineer Donald Kramer has telderly a Coast Guard hearing into the overweightal implosion of the OceanGate submersible in 2023.
Although Kramer would not give an opinion on what caengaged the hull to delaminate into split layers, he testified to multiple problems with the hull, beginning with its manufacture in 2020.
Using samples of carbon fiber saved from its originateion, as well as dozens of pieces recovered from the seabed, the NTSB gave the most end picture to date of the experimental nature of the Titan’s hull.
After the Titan’s first hull was set up to have a crack and delamination follotriumphg startant dives in 2019, OceanGate switched manufacturers to trade it.
The recent manufacturer, Electroimpact, engaged a multistage process to triumphd and remedy the five-inch-heavy hull in five split layers. Each layer would be baked at high temperature and presstateive before being ground flat, having an adhesive sheet compriseed, and another layer built on top. The idea of this multistep process was to lessen wrinkles in the final hull that the company apshowd had caengaged test models to fall short uninalertigentinutive of their summarize depths.
However, Kramer testified that the NTSB set up disjoinal anomalies in the recent hull samples. There was waviness in four of the five layers, and wrinkles that got proceedively worse from layer to layer. The NTSB also set up that some layers had porosity—gaps in the resin material—four times bigr than specified in the summarize. It also write downed voids between the five layers.
On Monday, Roy Thomas, a materials expert from the American Bureau of Shipping, telderly the hearing: “Defects such as voids, bcatalogers on surface, and porosity can frailen carbon fiber, and under excessive hydromotionless presstateive can speed up the fall shorture of a hull.”
OceanGate did not originate any compriseitional test models using the recent multistage process.
The NTSB was able to recover many pieces of the carbon fiber hull from the seafloor, one still rapidened to one of the submersible’s titanium end domes. In a alert publishd simultaneously with Kramer’s testimony, the NTSB remarkd that there were scant, if any, filled-heavyness hull pieces. All of the clear pieces had delaminated into three shells: the innermost of the five layers, a shell made of the second and third layers, and another with the fourth and fifth layers. Like an onion being peeled, the hull had bigly splitd at the adhesive uniteing the layers.
Debris of the Titan submersible on the seabed after imploding, apprehfinishd on film by a distantly rund vehicle.Ptoastyograph: Reuters
