Posted: December 24, 2015
After loading the pressure vessel into the test chamber, the pressure test commenced at 11:10am and proceeded as expected. Pressure was increased in stages, with pauses at pre-planned intervals.
At a pressure of 4,285 psi (the pressure at approximately 10,000ft depth) one of the hemispherical end caps failed just outboard of one of the large stainless steel inserts. The end caps were thought to be the most likely area of failure as the use of carbon fiber for hemispheres such as these is pushing the boundaries of carbon fiber design and fabrication.
Following the failure, the team immediately removed the model from the test chamber and, within hours, the two end caps were flown to Spencer Composites -- the manufacturer of the carbon fiber vessel.
The OceanGate team, along with engineers from Spencer Composites and the University of Washington Applied Physics Lab have begun a detailed analysis of the model and the testing data. This analysis may take a few weeks and we will share the results of the analysis when available. Until then, we will post updates and photos on our webpage as they become available.
Despite this setback, the test provides valuable proof that FWCF hemispheres are viable to depths of 10,000 feet and demonstrates that the benefits of carbon fiber are real. As a result, we remain very confident that we will overcome the extreme technical challenges needed to achieve a design operating depth of 20,000 feet.
Coincidentally, the day of the test we received an article titled the Innovation's Understanding Gap, from Aviation Week and Space Technology, that directly addresses the development process we have undertaken and reminds us all that these setbacks challenge us to learn from the questions raised and find the best possible means to reach our goals.
Editor-in-Chief, Aviation Week and Space Techology.
We agree. Failure is not an end-state. It as a step in the innovation process.
The next step for us is to apply what we learn from this first test, build the next test model, and test again.
Thank you for your ongoing support.
Test follow up information posted.
At a pressure of nearly 4300 psi, the stainless steel insert in one of the end domes separated from the carbon fiber. This allowed water intrusion into the vessel and aborted the test. The carbon fiber dome was the most likely failure point during the test of this experimental scale model. The engineering design team will begin evaluating the test data and vessel components to modify the design for the next test.
Test aborted. Possible vessel failure. The team will pull the vessel from the chamber to evaluate.
Increasing pressure to 5000 psi
Holding at 4000 psi -- 2800 meters!
Increasing pressure to 4000 psi
Holding at 3000 psi -- 2100 meters!
Increasing pressure to 3000 psi
Holding at 2000 psi -- 1400 meters
Increasing pressure to 2000 psi
Holding at 1000 psi for 5 minutes dwell time.
Increasing pressure to 1000 psi.
Holding at 500 psi and troubleshooting a data anomaly.
Bringing up pressure.
Pressure vessel loaded into pressure chamber.
Set up for the pressure test is underway. OceanGate and UW personnel are finishing the process of outfitting the pressure vessel with ballast and monitoring equipment before it is lowered into the pressure chamber.