Even as it filed updated paperwork with the U.S. Securities and Exchange Commission, Republic Airways Holdings isn't ready to take the plunge and sell shares to the public.

The March filing of an amended registration was a move just to keep its paperwork up to date, said a company spokesman. First filed two years ago, Republic has filed updates of its registration statement - a move that can speed up the approval of an initial public offering (IPO). The company is not required to make these filings. These public filings also provide a glimpse into the operations of the privately held regional carrier.

Republic has two subsidiaries: Chautauqua Airlines and Republic Airlines. Chautauqua has fixed-fee agreements with American Airlines [AMR], Delta Air Airlines [DAL], US Airways [UAIR] and United Airlines [UALAQ]. Republic Airways, which is still waiting on its final certification, plans to fly 70-seat Embraer [ERJ] 170 regional jets for United.

Market conditions are improving, but are not optimal for an airline to issue stock, according to one Wall Street analyst, who asked not to be named. The American Stock Exchange Airline Index had hit an eight-month low in mid-March when the rest of the stock market took a noise dive. The index has begun to bounce back. The index reached its 12-month high late last October.

The major uncertainty facing both Republic and potential investors is its reliance on three troubled airlines for the bulk of its income stream, the analyst said. While United remains in bankruptcy, US Airways is still trying to find a profitable operating formula one year after exiting bankruptcy, and Delta just had its credit rating reduced because of its inability to reduce its operating costs, particularly pilots' wages.

According to the filing, in 2003, US Airways accounted for 40 percent of Republic Airways' operating revenue, Delta accounted for 29 percent and American accounted for 23 percent. For the first two months of 2003, Chautauqua provided feeder service to America West [AWA] until it closed its Columbus hub. The company has not revealed how much it expects to earn from its United contract.

The analyst said that if the company did not rely so heavily on US Airways, a stock offering would be much more favorably received at this time.

Over the last three years, Republic Airway's bottom line has improved. The company posted a net profit of $33.8 million in 2003 on revenue of $421.1 million. In 2001, it earned $5.6 million on revenue of $238.6 million.

Its operations have also improved. In 2003, it generated 12.2 cents revenue per available seat mile (RASM) with its planes 64.1 percent full. Its cost of operation per available seat mile (CASM) last year was 10.2 cents. In 2002, Republic's RASM was 13.4 cents, but its CASM was 12 cents. And its load factor was 61.6 percent.

Republic has shed its Saab 340 turboprops and doubled its fleet of Embraers to 83. It is now operating each Embraer 10.2 hours per day.

In the revised registration statement, Republic Airways said it would be seeking a maximum of $143.7 million for the yet-to-be scheduled offering. In an update filed last July, Republic indicated it would be seeking $57.5 million in an offering.

Republic said that the bulk of the offering receipts would be used for general corporate purposes, including deposits on new aircraft. It would use $21.6 million to pay off loans provided by its sole stockholder, Wexford Capital. Even after the offering, Wexford intends to hold onto enough shares to control the airline.

The Wall Street analyst said potential investors would look favorably upon Republic because the vast bulk of the proceeds will be reinvested into the company. If Wexford were using the opportunity to cash out its investment - as many IPOs are staged - the reception might be a bit cooler, he said.