By Geoff Fein
The General Dynamics [GD] variant of the Littoral Combat Ship (LCS) uses less fuel per hour during higher rates of speed than the Lockheed Martin [LMT] vessel, according to a Navy document.
The one-page LCS Consumption Curves shows that both ships use about the same amount of fuel, or barrels, per hour between zero and 16 knots.
At five knots, the General Dynamics aluminum trimaran uses 3.2 barrels per hour versus 3.9 for Lockheed Martin’s semi-planing monohull. At 14 knots, the General Dynamics ship uses 11.3 barrels per hour while the Lockheed Martin ship uses 12.7. At 16 knots, the Lockheed Martin ship uses 18.4 barrels per hour while the General Dynamics ship uses 15.5, according to the document.
The one-page consumption curve is part of a larger Navy LCS Total Ownership Cost Baseline Estimate Documentation dated Aug. 25, 2009.
But, according to the document, at speeds above approximately 20 knots, there is a definite difference in fuel use between the two ships.
At 30 knots, the General Dynamics trimaran burns through 62.7 barrels per hour, while the Lockheed Martin monohull uses 102.9 barrels per hour, according to the document. At 40 knots, the Lockheed Martin ship burns through 138 barrels per hour while the General Dynamics ship uses 105.7 barrels per hour.
But how often will the Navy operate either ship beyond 16 knots?
According to Lockheed Martin, LCS won’t be spending a lot of time cruising at top speed.
“Fuel economy is dependent on the operational profile of the ship. The Navy’s LCS mission profile, a significant criteria used to design LCS, results in the ship operating at speeds below 16 knots more than 90 percent of the time,” Kimberly Martinez, a company spokeswoman, told Defense Daily yesterday. “At this speed, Lockheed Martin’s analysis indicates its design displays better fuel efficiency due to its economical 16-cylinder diesel engines.”
And Lockheed Martin maintains that its semi-planing monohull design meets all of the Navy’s requirements.
“Fuel efficiency is just one component of total ownership cost. Acquisition cost, manpower, maintenance, training and support costs are other key elements and Lockheed Martin believes its design provides the most cost-effective balance across all elements,” Martinez added.
The Navy declined yesterday to comment for this article.
Naval Sea Systems Command (NAVSEA) and the program executive office ships “cannot comment on this document due to the ongoing competition,” Patricia Dolan, a NAVSEA spokeswoman, told Defense Daily yesterday.
Fuel consumption has become the focal point of efforts by Mobile, Ala.-based Austal USA and Sen. Jeff Sessions (R-Ala.) to point out that the General Dynamics-Austal USA-built LCS is more fuel efficient.
Bill Pfister, vice president, external affairs for Austal USA, told attendees on Feb. 23 that one of the principle benefits of the aluminum hull LCS is energy efficiency (Defense Daily, Feb. 24)
“The number one reason we have designed a lightweight multi-hull ship is that it is a derivative of ships that commercial owners buy when they want to save fuel,” Pfister said at the Feb. 23 symposium.
Austal USA and General Dynamics are building a LCS based on commercial ferry designs.
At last week’s Senate Armed Services Committee hearing, Sessions raised the issue of fuel consumption during questioning of Navy leadership. Sessions asked Navy Secretary Ray Mabus if the LCS request for proposal (RFP) should adequately reflect the lifetime fuel consumption costs of the vessels involved (Defense Daily, March 1).
Mabus said he believed the RFP does that.
“At this point in the RFP process, senator, we’re expecting bids in. And based on our view…of the analysis that we have done previous on the two ships that we have, and on the projected use of those ships, frankly it’s unclear if either has an advantage on energy consumption,” Mabus said at the Feb. 25 hearing.
General Dynamics and Lockheed Martin both received their LCS RFPs Jan. 27. Responses are due back to the Navy no later than March 29. The service anticipates awarding a contract for two LCS with options for eight more, later this summer. The Navy will build its fleet of 55 LCS based solely on the winning design.