* After 8 moves, 18 leadership jobs, Hewson named CEO
* Unassuming style may help Lockheed mend Pentagon fences
* Champion for women in male-dominated sector
By Andrea Shalal-Esa
WASHINGTON, Nov 9 (Reuters) - Marillyn Hewson likes to joke that she's done nearly every job at Lockheed Martin Corp during her 29 years with the biggest U.S. weapons maker, but that experience should come in handy when she moves into the top job in January.
Hewson moved eight times and held 18 different leadership roles at Lockheed before she was named on Friday as the company's president and chief operating officer.
Hewson, 58, was elected to the job at an emergency board meeting after Chris Kubasik, 51, was fired for having an affair with a female subordinate. She will also become chief executive officer in January, when Bob Stevens retires, a job that Kubasik was supposed to take.
"Marillyn is an exceptional leader with impeccable credentials," Stevens told reporters. "She knows our business, our customers, our shareholders, our commitments and our employees."
Hewson was supposed to move into the No. 2 spot in January, but Kubasik's ouster accelerated that move, and unexpectedly propelled the avid golfer and reader into the top job.
Hewson's promotion means women will hold the top jobs at three of the six largest U.S. defense contractors come January, with Hewson at the helm of the biggest of the three, just as the industry braces for the first downturn in over a decade.
Hewson and Phebe Novakovic, the incoming CEO at General Dynamics Corps, will take power a day before $500 billion in additional defense spending cuts are due to start taking effect, cutting into revenues across the sector.
They join pioneer Linda Hudson, the chief executive of the U.S. unit of Britain's BAE Systems Inc.
"It's about time there were more women in these top jobs instead of all these boring old white guys," said Washington lobbyist Caren Turner. "I just hope they're not being put in spots to be thrown off the fiscal cliff."
In her new job, Hewson will oversee nearly $47 billion in revenues and some of the U.S. government's most critical and sensitive weapons programs, including the stealth F-35 fighter jet, RQ-170 classified drones, advanced satellites for spying and positioning, Aegis missiles and a new coastal warship.
Her unassuming style and people skills may be just what Lockheed needs to mend fences with the Pentagon on the troubled F-35 program, which has been restructured three times.
Negotiations about a fifth batch of F-35 jets have dragged on for nearly a year, prompting one top Pentagon F-35 official to describe ties between the company and the government as the "worst I've ever seen".
The company recently warned shareholders that it faced a termination liability of $1.1 billion dollars if those talks weren't completed by the end of the year.
Defense consultant Loren Thompson said Hewson was a pleasant person who could also be tough when appropriate.
"Marillyn's elevation is probably a better outcome for employees and shareholders," Thompson told Reuters, noting that Kubasik's sarcasm sometimes rubbed people the wrong way.
"She's a very capable executive and she's widely liked inside the company. She's tougher than nails when she needs to be, but never tougher than she has to be," he added.
In 2012, Hewson was ranked No. 19 on the annual Fortune magazine list of the most powerful women in business.
She has long been a champion of helping other women move up the corporate ladder and in early October, Hewson and Hudson spoke about their careers in the traditionally male-dominated defense business at Fortune's "Most Powerful Women" summit.
On Thursday, Hewson kicked off an annual meeting for over 300 top female Lockheed executives at the company's Bethesda headquarters -- an event she helped initiate years ago.
Born in Junction City, Kansas, Hewson's father died when she was just nine, leaving her mother with five young children. Hewson went on to earn a bachelor degree of science in business and a master's degree in economics at the University of Alabama.
Her first job was as an economist at the Bureau of Labor Statistics in Washington, but she soon joined Lockheed, and then worked her way up by taking every job she was offered.
In 2005, upon being singled out as a woman "worth watching" by a diversity organization, Hewson said she believed that success depended largely on being willing to take risks and staying open to new ideas. Working well with others also helped, she said, adding, "You may be the smartest person in the room, but if you can't get along with others, you will not succeed."
Offering some advice to other women in the corporate world, Hewson said: "Bottom line is, do your best and don't set limits on what you think you can do. And one of the best things you can do for yourself is to learn to forgive yourself for not knowing all the answers when you're knee-deep in new territory."
Hewson has held senior jobs in Lockheed's aeronautics, services and logistics businesses, and internal auditing division. Her latest job was running its electronic systems sector.
In April, Hewson and Kubasik joked lightheartedly about how far they'd come since their younger days when he worked at a hardware store and she made ice cream cones at Dairy Queen.
On Friday, Hewson struck a more serious tone. She said the company had proven resilient during previous management changes and would weather what she called a "temporary distraction."
She said Lockheed remained focused on cutting costs, meeting its commitments to customers and investing in research and development of products for the future -- including a range of unmanned vehicles for land, sea and air.