Despite these advantages, Rush says there has been a hesitancy to use composites for pressure vessels because reliability and failure rates were not as well-known as steel and titanium. But he believes that the high-volume manufacturing and testing of composites that’s occurred in many industries – especially aerospace – have now alleviated this uncertainty.
Still, OceanGate faced challenges designing a carbon fiber cylinder. Matching the lineal displacement of composite with the glass end cap created issues. So did transitioning the end of the carbon fiber cylinder into the titanium portion, which has a different load pattern. The company spent a lot of time considering how to reduce the stress in joints where the cylinder and end caps come together.
Construction on the first carbon fiber pressure vessel is scheduled to start in March or April, though a manufacturer has not yet been chosen. One company in the running is Boeing, a preferred vendor for OceanGate. Whatever manufacturer is selected, Rush anticipates that the Cyclops will be built using individual fiber placement with a robotic arm to ensure predictability and uniformity of resin and fiber areas. Manufacturing will present challenges, too. For instance, the carbon fiber hull is seven inches thick, so it will require multiple cure cycles.
Rush is optimistic that such issues will be resolved and the Cyclops will garner commercial appeal thanks to its design: The hull will be larger than existing submersibles so it will be able to carry five passengers. The five-foot wide, glass viewing dome will give passengers a 180-degree view – a marked departure from existing small view ports. Rush says these and other improvements make Cyclops well suited to numerous purposes, including inspection, repair and maintenance for the oil and gas industry; assaying and sampling of minerals for mining; and filming of documentaries.
Rush plans on being an early adopter, too. After missing out on that sub ride all those years ago, Rush will be a passenger on Cyclops’ first dive. “I wouldn’t give that up!”