In a surprise move, Lockheed Martin [LMT] is turning to its maritime sector chief to work on the F-35 Joint Strike Fighter (JSF), a troubled program the company has bet much of its financial future on, according to sources.

 Lockheed Martin CEO Bob Stevens has asked Orlando Carvalho, president of the company’s Mission Systems and Sensors (MS2) unit since January 2010, to assist current F-35 program manager Larry Lawson because of his track record successfully executing programs, according to sources. The move is likely an interim step as Carvalho, 52, gets up to speed and ultimately takes a larger role in JSF.

When asked about the move, a company spokesman said as a matter of policy it did not discuss executive appointments before public announcement.

The decision to move a division president, currently presiding over a multi-billion business with over 500 programs and 15,000 employees, shows the importance the company is placing on righting the JSF. The Pentagon’s budget request for JSF is $9.4 billion in FY ’12 billion alone. Over time, the program’s value is expected to total hundreds of billions more.

Because of the JSF’s complexity and importance to the future of the Lockheed Martin, the company simply had to have its top players on the field, one source said.

Nevertheless, the timing is unexpected. The past week at the Paris Airshow, top JSF officials granted multiple interviews on the program and offered no hint of changes in the program’s leadership, according to published reports.

JSF has come under assault by overseers in the Pentagon and Capitol Hill. Earlier this year, the Pentagon delayed start of the full-rate F-35 by a year and put the Marine Corps short takeoff vertical landing variant on a two-year probation to work out technical issues.

The Pentagon has also estimated JSF’s development will take and additional 1.5 years and cost $4.5 billion more than estimated one year ago (Defense Daily, May 20).

In addition, Carvalho will be leaving MS2 as the division prepares for a grueling battle with industry rival Raytheon [RTN] and perhaps others for a massive upgrade contract to the Aegis combat system.