HSLA 115 Flight Deck for CVN 78 Class Carriers

The Navy seeks solutions to reduce weight and lower the center of gravity for surface ships to improve their performance at a reasonable cost. This Navy ManTech Metalworking Center project focused on a goal of reducing topside weight and lowering the center of gravity on the CVN 78 class of ships.

The Integrated Project Team pur-sued an alternate path—increasing the performance and strength of HSLA-100 steel (high-strength, low-alloy) through heat treatment so that it could be used at reduced thickness—to reduce the weight and meet performance requirements.

HSLA-115 received successful vendor qualification of first article, full-size production plates, weld qualification evaluations and explosion testing. NMC and the Integrated Project Team successfully submitted Material Selection Information certification data ahead of schedule to support key shipyard need dates. It was subsequently approved in January 2009. 

The Future Aircraft Carriers Program Office approved the incorporation of HSLA-115 into a CVN 78 application baseline design. HSLA-115 has been incorporated into the ship specifications and fabrication document. In March 2009, the Northrup Grumman Shipbuilding - Newport News (NGSB-NN) procured the first order of HSLA-115 for CVN 78. In fact, NGSB procured more than 2000 tons of HSLA-115 and the first plates have been successfully delivered to the shipyard. NGSB-NN is currently fabricating CVN 78 applications with HSLA-115 production plates. HSLA-115 may be considered for additional future applications to improve performance and reduce weight.