The chief financial officer of financially troubled US Airways Group Inc. has resigned, less than six months after taking the job and just a month after the airline filed for bankruptcy protection for the second time in as many years, the company announced yesterday.

David M. Davis, 38, who joined the Arlington-based carrier as vice president of financial planning and analysis in April 2002 and was promoted to CFO in May this year, will leave the company next month to become CFO at Houston-based Kraton Polymers LLC, a chemical company. Davis will be replaced by Ronald E. Stanley, 57, who joined the company's board of directors in May and has chaired its audit committee.

A source close to the airline said Davis was not forced to resign and informed the airline's board of directors over the weekend that he had accepted the new position. He will not receive a severance package from the airline, a company spokesman said.

Airline industry observers said Davis's departure signals increased trouble for the airline. Davis was the lead executive who testified during the airline's bankruptcy hearing earlier this month.

"This doesn't look good," said Mike Boyd of the Boyd Group. "You don't want to shake up your senior management staff at a time like this."

Davis was not available for comment yesterday.

Analyst Helane Becker of the Benchmark Co. said Davis either thought the airline was not going to emerge from its Chapter 11 bankruptcy proceedings or assumed that if the carrier did emerge, a new management team would be brought in.

The airline has been struggling to emerge from reorganization and reinvent itself as a low-fare carrier. It recently cut senior executives' pay 5 to 10 percent. In addition, the bankruptcy court allowed the airline to implement a 21 percent cut for the majority of its workers through February.

"Talented individuals are being recruited away to other companies that pay better money than US Airways is paying or can pay," US Airways spokesman David Castelveter said yesterday. "We're losing management at a rate of 20 percent a month, which is a very high number."

Davis, a veteran of both Delta Air Lines Inc. and Northwest Airlines Corp., was making $319,550 a year at the time of his promotion to CFO in May, according to regulatory filings.

Davis's replacement, Stanley, has had previous experience in finance, including as chief operating officer and director of HSBC Equator Bank PLC.

US Airways also announced yesterday the election of George M. Philip, the executive director of the New York State Teachers' Retirement System, to its board of directors.