PARIS — The successful Feb. 12 launch of the enhanced version of Europe’s Ariane 5 rocket has put the Arianespace launch consortium back in the running as a major commercial-launch competitor, saved the life of a Loral-led satellite operator and removed a shadow cast over Europe’s near-term government space budget.

The launch of the Ariane 5 ECA vehicle, which failed in its inaugural flight in December 2002, placed the Xtar-Eur satellite, owned by start-up operator Xtar LLC, into geostationary transfer orbit.

Xtar-Eur, built by Space Systems/Loral of Palo Alto, Calif., weighed 3,772 kilograms at launch and was accompanied by the 3,496-kilogram Maqsat-B2 dummy satellite, which remained with the Ariane 5 upper stage. Also launched was the 129-kilogram Sloshsat experimental satellite that was released into orbit to measure the effects on a spacecraft’s control of a fluid — in most cases fuel, but in this case 33.5 liters of water — that sloshes in its tanks.

The new Ariane 5, equipped with a remodeled Vulcain 2 main-stage cryogenic engine and a cryogenic upper stage borrowed from the now-retired Ariane 4 vehicle, is capable of placing satellites with a combined weight of more than 9,000 kilograms into geostationary transfer orbit. That compares with the 6,000-kilogram limit of the standard Ariane 5G variant that Arianespace was forced to rely on for the past two years.

With the Ariane 5G too expensive to profitably launch most satellites one at a time, and the Ariane 5 ECA out of service, the Evry, France-based Arianespace consortium has been at pains to maintain financial equilibrium.

It returned to profitability in 2004 despite a sluggish commercial market only because of a billion-dollar bailout agreed to by European Space Agency (ESA) governments in the wake of the December 2002 failure.

ESA Director-General Jean-Jacques Dordain said Feb. 17 that in hindsight it is remarkable that ESA member states approved the bailout package just five months after the failure. These governments also financed the Feb. 12 flight.

Arianespace Chief Executive Officer Jean-Yves Le Gall said Arianespace will now base its business on the Ariane 5 ECA for the foreseeable future and will not entertain thoughts of any new variants . “This is our workhorse vehicle for the coming years,” Le Gall said.

Industry officials said Arianespace’s most pressing task now is to conduct additional Ariane 5 ECA launches as quickly as possible to solidify the vehicle’s credibility in the eyes of customers and insurance underwriters.

As the only rocket now operating in the commercial market capable of lofting two big telecommunications spacecraft at once, the Ariane 5 ECA presents a challenge to the insurance sector. Underwriters have said they will want to see at least two successful missions before covering a two-satellite launch that could carry an insured value surpassing $400 million. That will tax the limit of today’s space-insurance market.

Le Gall said in a Feb. 17 interview that Arianespace expects to launch another five rockets this year, with two more Ariane 5 ECA vehicles expected among them. The next Arianespace launch, of an Ariane 5G, is scheduled for mid-April. It will carry the French Defense Ministry’s 3,700-kilogram Syracuse 3A telecommunications satellite and the Telkom-2 telecommunications satellite for PT Telkom of Indonesia.

Built by Orbital Sciences Corp. of Dulles, Va., Telkom-2 will weigh about 2,000 kilograms at launch and is substantially smaller than the average telecommunications satellite on the market today.

Le Gall said Arianespace had not yet determined what satellites would be aboard the next Ariane 5 ECA vehicle, which he said is expected to launch this summer.

For Xtar LLC, meanwhile, the Feb. 12 launch was a live-or-die matter. The company, which plans to market Xtar-Eur X-band capacity to defense forces, currently has no revenue stream. One of its biggest potential customers, the U.S. government, refused to commit to any purchases until the satellite was operating in orbit.

The Spanish Ministry of Defense has leased three and one-third of Xtar-Eur’s transponders for about a year, until the Loral-built Spainsat satellite is launched in early 2006. Xtar LLC is 56 percent owned by Loral Space and Communications of New York and 44 percent by Hisdesat S.A. of Madrid.

Xtar Chief Operating Officer Denis Curtin said in a Feb. 16 interview that the company will immediately begin marketing Xtar capacity to U.S. and allied defense departments. “We have had initial expressions of interest from several countries and we expect that with our satellite now functioning, customers will soon follow,” Curtin said.

Xtar is the second company whose existence was riding on an Ariane vehicle. In 1988, satellite-fleet operator PanAmSat Corp. launched its first satellite on an untested Ariane 4 rocket. PanAmSat, like Xtar, paid next to nothing in advance for the launch, and did not insure it.

The Ariane 5 ECA success gives European government space budgets some badly needed financial maneuvering room. With the specter of an unqualified Ariane 5 ECA partially removed, ESA will be lobbied hard for new programs on future launch vehicles and satellites.

The lobbying has already begun. Francois Auque, chief executive officer of EADS Space, the Ariane 5 prime contractor, told reporters before the launch that a success should free up resources for a future-launcher program that ESA was forced to freeze after the December 2002 failure.

Satellite builders, for their part, say ESA’s attention should now turn toward them. “The launch was a big relief for European industry as the investment in Ariane has been quite sizable,” said Paul Kamoun of Paris-based Alcatel Space, a satellite builder. “Let us hope that some additional budgets can be unblocked and devoted to satellites.”

Peter B. de Selding was the Paris bureau chief for SpaceNews.