United Airlines stock lower after temp CEO announced

UAL appoints Brett Hart as acting CEO

United Airlines finally got around to acknowledging that its new CEO suffered a heart attack, and announcing who would replace him temporarily, after days of vague statements from the aviation giant. But Wall Street didn't seem too impressed with the temp — who has just five years of airlines experience.

Shares in United Continental, the holding company for the airline, dropped Tuesday morning at the market open on heels of the news late Monday that the company's general counsel, Brett Hart, will be filling in temporarily for ailing CEO Oscar Munoz. Both the Dow Jones industrial average and S&P 500 were marginally higher Tuesday.

The airline said Hart would be working "closely" with its board chairman and the company's "executive team" to run United.

Brett J. Hart, acting CEO of United Airlines.
Source: United Airlines

UAL shares were down more than 1 percent during Tuesday trading, reversing an upward swing in the stock seen Monday, when United said it was on the verge of sorting out its "corporate governance process" that was set in motion when Munoz was hospitalized last week.

The airline was criticized Monday by experts in public relations crisis management and corporate governance for not confirming reports from days before that Munoz had had a heart attack, and for not promptly naming someone to lead the company, as least on a temporary basis, while he was ill.

In a statement Monday night, United said that Munoz had a heart attack on Thursday, adding that "at this time, it is too soon to know the course of treatment and timing of recovery."

"The UAL board of directors has named Brett J. Hart, currently United's executive vice president and general counsel, as acting CEO. This appointment is effective immediately," the company said. "Hart will work closely with Henry L. Meyer III, non-executive chairman of the board, and United's experienced executive team to run the company in Munoz's absence."

Hart cited that team in his own statement, saying that "Oscar's agenda is focused on customer service, teamwork and innovation, and I, along with the executive team, will continue to move quickly to implement it."

"We believe strongly that we can continue to make steady progress on increasing shareholder value by working together to deliver a great product to our customers."

United also said "the board of directors remains actively engaged in preparing for all potential outcomes regarding the company's leadership structure."

Oscar Munoz
How United is handling the PR for its CEO health crisis

Sources on Wall Street who follow United and who spoke with CNBC said that when they discuss the airline's "executive bench at United ... Brett Hart's name is not one that has come up."

Hart's temporary assumption to the CEO office comes less than six weeks after Munoz, who has a long track record in the railroad industry, was elevated to the top job at United after serving on its board.

Munoz was named CEO after former CEO Jeff Smisek was ousted, amid an ongoing federal criminal probe into whether the airline sought to curry favor with the chairman of the Port Authority of New York and New Jersey and get improvements made to Newark Liberty Airport by restoring a money-losing flight to South Carolina, where he has a second home.

In its announcement about Hart late Monday, United noted he "has been responsible for government and regulatory affairs, corporate real estate, customer experience, corporate security, community affairs, contact centers and food services."

"Prior to joining United in 2010, Hart served as executive vice president, general counsel and corporate secretary at Sara Lee, partner at Sonnenschein Nath & Rosenthal, and special assistant to the general counsel at the U.S. Department of Treasury."

The Wall Street Journal, in an article last week, said that when Hart was at Sara Lee in May 2010, the food company said that then-CEO Brenda Barnes was taking a medical leave, but did not reveal any details about what was wrong with her, or how long she as expected to be away. That drew complaints from some shareholders. Almost a month later, the Journal noted, Sara Lee said Barnes had had a stroke, and she left as CEO shortly afterward.

United chairman Meyer said Monday, about Hart, "Brett has taken on increasing responsibility beyond general counsel over the last few years in the operations and customer-facing areas of the company. I am confident in his ability to continue to implement the company's strategy and Oscar's mission of bringing United's people together around the shared purpose of becoming the best airline for our customers and employees."

— CNBC's Phil LeBeau contributed to this report.