Launch failures occurring at two of the three principal commercial-launch service companies in 2007 had a less-than-expected impact on the health of the commercial satellite sector but has placed more pressure on the

launch companies to stick to

their schedules in 2008.

The January failure of a Sea Launch Co. rocket kept that vehicle out of service for more than nine months. When Sea Launch was ready to return to flight, satellite delays and unusually rough subsurface ocean currents scuttled the company’s attempts to launch late in the year.

Long Beach, Calif.-based Sea Launch currently has rescheduled the flight of the Thuraya 3 mobile communications satellite for mid

January and hopes to launch four more times this year, according to Sea Launch officials.

Sea Launch also expects to inaugurate its Land Launch operation – the same basic Russian/Ukrainian Zenit vehicle, but operated from the BaikonurCosmodrome in Kazakhstan – this year, with up to three launches planned, Sea Launch Chief Financial Officer KjellKarlsen said in a Nov. 21 interview.

A September failure sidelined the Proton launch vehicle, but for less than two months, in part because the Russian board of inquiry recovered some of the defective hardware and isolated the cause of the failure in short order.

Both McLean, Va.-based International Launch Services (ILS), which commercializes the Russian-built Proton

, and Europe’s Arianespace launch consortium plan six or seven commercial launches in 2008, according to the two companies’ chief executives.

ILS President Frank McKenna said

all three major commercial-launch services providers are under pressure to deliver on their promised launch rates this year. “The year 2008 has got to be a year of performance,” McKenna said in a Jan. 3 interview. “The commercial launch industry has got to perform. We need to deploy a large number of satellites, and we’ve got to be consistent as an industry.”

McKenna said ILS has scheduled six or seven commercial launches in 2008, with the Russian government completing Proton’s manifest with between three and five government missions.

McKenna dismissed concerns that a recurring dispute between the governments of Kazakhstan – whose territory includes the Russian-run BaikonurCosmodrome spaceport – and Russia will result in a reduced number of Proton launches in 2008. Kazakh authorities

repeatedly have said Russia has insufficiently compensated Kazakhstan for pollution cleanup due to Proton activity. “This is really unfounded speculation,” McKenna said. “The two sides settled out the issues in December as planned. No impact at all is expected.”

McKenna also said he is optimistic that ILS can conduct most of its planned 2008 launches early in the year. “We are front-loaded this year,” McKenna said. “Every satellite we have manifested for the first six months of the year is on schedule.”

ILS’ decision in 2006 to narrow its target market to satellites weighing more than 4,000 kilograms is paying off, McKenna said. The average ILS satellite launch contract

ILS in 2007 is for a spacecraft weighing between 5,500 and 5,600 kilograms, he said. The July launch of the DirecTV 10 satellite qualified the enhanced-version of the Proton-M launch vehicle, which ILS says can carry a satellite weighing between 6,200 kilograms and 6,300 kilograms into geostationary transfer orbit.

Evry, France-based Arianespace continues to seek commercial satellites of almost all classes. The Ariane 5 vehicle, whose main business is carrying two telecommunications satellites at a time into geostationary transfer orbit, has a capacity of about 9,500 kilograms.

Arianespace Chief Executive Jean-Yves Le Gall said the company, which set a record in 2007 by launching six Ariane 5 vehicles, is aiming for seven or eight launches in 2008, including a launch of Europe’s Automated Transfer Vehicle, a cargo vessel to serve the international space station.

“Today we are reaping the dividends from decisions made several years ago,” Le Gall said in a Dec. 19 interview. “We have concentrated on a single vehicle design, the Ariane 5 ECA, and we have demonstrated flexibility to our customers. In some of our launches in 2007, there have been only a few months between the signing of the contract and the launch.”

Le Gall said he is concerned that the tightened credit market may make it difficult for some planned startup satellite projects to secure needed financing. But the continued need for satellite capacity for high-definition television, broadband connectivity and mobile applications gives the market a longer-term stability.