The admiral in line to lead the Navy said yesterday he will “keep looking at” the Littoral Combat Ship (LCS) program, which has come under fire from lawmakers following corrosion and hull-cracking in the initial vessels.

Adm. Jonathan Greenert told reporters yesterday he supports the current structure of the LCS program, to a point. President Barack Obama nominated Greenert, the vice chief of naval operations (CNO), to succeed Adm. Gary Roughead as CNO.

“I stand by it now,” Greenert said about the rocky effort to build two varieties of littoral ships. “I will keep looking. We’ve got a way to go. We’ve got to get (the ships) out on time. We’ve got to bring them into the fleet and integrate them. As it stands now and I look at it, it’s a good program. We need to work on it.”

His comments came after his confirmation hearing before the Senate Armed Services Committee (SASC), during which Ranking Member John McCain (R-Ariz.) blasted the LCS acquisition strategy, predicting the program will cost more than the Navy estimated and become “simply unsustainable.” The senator called on Greenert to give the effort to build 55 shore-hugging ships his “serious attention.”

The two-ship program has had headline-grabbing problems with cost overruns and delays in past years, and the Navy previously canceled the first ships under contract with Lockheed Martin [LMT] and General Dynamics [GD].

McCain and lawmakers including Rep. Duncan Hunter (R-Calif.) have raised fresh concerns about the LCS program. Recent inspections found aggressive galvanic corrosion on General Dynamics’ USS Independence (LCS-2), the first of the aluminum-trimaran hulled littoral ship it built for the Navy. Word of that corrosion came after news in March that the hull of the USS Freedom (LCS-1), Lockheed Martin’s first semi-planing steel-monohull LCS, cracked during sea trials.

Hunter and Rep. Rob Wittman (R-Va.), both House Armed Services Committee members, asked the Government Accountability Office on Wednesday to review the LCS program in light of the recent structural problems. Hunter asked the Navy earlier this month to conduct a formal review of the LCS program, but service Secretary Ray Mabus maintained the service has overcome many past LCS problems.

McCain and six other senators sent Pentagon acquisition chief Ashton Carter a letter earlier this month with series of questions about the LCS program, including why Carter allowed the LCS ships to proceed in the acquisition process based on Navy cost estimates that independent cost estimators said were inaccurate.

The Navy changed its acquisition plan for the LCS program last year, dropping plans to buy 10 LCSs from either Austal USA, which partnered with General Dynamics on LCS-2, or a Lockheed Martin-Marinette Marine team. The Navy now plans to buy 10 copies of each ship design and have additional shipbuilders compete in the future to build forthcoming ships of the same two designs.

McCain opposed this change in the Navy’s LCS acquisition plan. He said yesterday he continues to oppose the dual-source block-buy strategy, and believes “the true lifecycle cost for buying and sustaining both LCS variants will be considerably more than what the Navy has estimated.”

“I’m sure you share my frustration that following an $8 billion taxpayer investment in the LCS program, the Navy continues to lack a single ship that is operationally effective or reliable,” McCain said to Greenert.

Also lamenting cost growth with the F-35 Joint Strike Fighter program, McCain said he’s “deadly serious about the fact that these costs of both of these programs are simply unsustainable” and “strongly” recommended Greenert give both his “serious attention” as CNO.

The LCS effort received some words of support from Sen. Jeff Sessions (R-Ala.) during Greenert’s confirmation hearing.

Sessions highlighted how the littoral ships are intended to be more affordable and require less personnel to operate than larger ships.

Greenert said he’s “very impressed with the potential that those ships will bring,” with their “speed, volume, agility and the ability to adapt.”

“We just have to bring them in on time, budget and schedule,” he said.

Sessions downplayed the corrosion issue with LCS-2, which is made in his state, saying that while it may cost from $1 million to $3 million to fix that ship, the corrosion could be avoided on future ships for a small cost.

Greenert expressed optimism to reporters about the Navy’s ability to manage the corrosion with the ship.