WASHINGTON — When Leanne Caret assumes the leadership of Boeing's defense, space and security business on March 1, substantial challenges will be waiting to greet her.

In an abrupt move last week, the world’s second-largest defense contractor announced longtime Boeing defense executive Chris Chadwick’s retirement? resignation and Caret’s subsequent promotion to head its $30 billion defense unit.

In a statement announcing the personnel changes, Boeing chairman, president and CEO Dennis Muilenburg described Caret, 49, as "an experienced and inspirational leader," ready to "build on the existing strengths of our defense, space and security business and grow it for the future."

But the question remains: Where will Caret find growth opportunities for the business, which has fluctuated between $33.66 billion in revenues in 2009 and $30.88 billion in 2014? Many of Boeing’s signature platforms are approaching the end of their lifespans, with production runs projected to wind down for the F-15 Silent Eagles, F/A-18 Super Hornets, and CH-47 Chinook and AH-64 Apache helicopters in the coming decade.

Leanne Caret will take over as head of Boeing's defense, space and security business on March 1.

Photo Credit: Courtesy of Boeing

Additionally, the US Air Force did not select the Boeing-Lockheed Martin team to build its Long Range Strike Bomber (LRS-B), estimated to be worth $80 billion over the life of the contract. On Feb. 16, the Government Accountability Office denied Boeing's protest, and Boeing announced ten days later that it would not pursue the matter further, either with the GAO or in federal court.

"If you look at the landscape, it's not happy" for Boeing, said Richard Aboulafia, an analyst with the Teal Group who focuses on aerospace. "A change in leadership could conceivably improve their short term hopes for a sale here and there, but in the long term strategic picture, it's still extremely difficult."

Missing out on LRS-B is "extremely painful" for Boeing, he said, particularly with so few platforms being developed. "You get one shot per decade, and skipping a decade is possibly no longer an option."

The next big-ticket military aircraft competition is for the Air Force's T-X trainer, which is expected to be awarded in 2017.

Ron Epstein, a defense analyst with Bank of America, said the Air Force trainer competition is virtually a must-win for Boeing.

"T-X is paramount now, if you want to stay in the [combat aircraft] business," he said.

Aboulafia was less sanguine, suggesting that even a T-X win might not be enough.

"What you've got is a battle to see who will be around to bid on the next fighter program, and unless they can keep their legacy fighters going and rejuvenated longer than planned, T-X almost certainly won't do much to keep them in the running," he said.

Loren Thompson, an analyst with the Lexington Institute and defense industry consultant with close ties to Boeing, noted that the T-X contract award is likely to be worth at least $8 billion, even before support costs are included.

"You can bet that they have sharpened their pencils for that. But they are not willing to let go of the bomber yet. They are sure that on the merits they should have won," he said. "Boeing simply doesn't believe that the program can be executed on the terms that were signed up for."

Caret's 28-year tenure with Boeing includes stints as president of Boeing's defense unit's global services and support business, vice president and general manager of vertical lift, a division of Boeing Military Aircraft, and CFO of the entire business unit.

Within the company, she is viewed as a star and a fast-riser, Thompson said.

"Caret has been groomed for senior management through a series of increasingly important positions over the last decade," he said. "Because she has passed through a diverse series of senior jobs, she understands the platform side of the business and the services side of the business about equally well."

Since the 1990s, Boeing's strategy has been to keep one foot in the defense sector and one in the commercial aircraft business, with the idea that one sector's success would cushion the blow if the other stumbled. Commercial aerospace is a cyclical business, and there are indications that it might be slowing.

"We've just had an unusual super cycle, but as headlines indicate, it might not last forever," Aboulafia said. Boeing is also facing what he described as "the giant overhang" of deferred production costs on its 787 Dreamliner.

"The fundamental challenge that Caret will face as head of all Boeing defense is how to bolster revenue at a time when demand for commercial jetliners may be softening," said Thompson. Time will tell how successful Caret will be, he said.

"She has done very well at every other job she has been in. You don't get put in charge of $30 billion at Boeing unless you've got a pretty stellar record," Thompson said.

Epstein and Aboulafia downplayed the potential impact from Boeing's change of personnel at the top of its defense unit.

"Does it change the outlook for Boeing defense from an investor perspective? No," said Epstein. "Why would it? Are they putting in some magic rainmaker from a competitor? No."

"She's known as a very dynamic executive, and maybe that's what they think they need there. But on the other hand, it's hard to see how a change in leadership is going to make a material impact on their circumstances," said Aboulafia. "They are in a very difficult position."

Twitter: @andclev