The successful launch Nov. 16 of the enhanced version of Europe’s Ariane 5 rocket will permit the Arianespace launch consortium to move to a single Ariane 5 product line as it seeks to regain market share from its competitors.

The launch also could lead to a restructuring of the company’s shareholder base. EADS Space Transportation, a division of European aerospace giant EADS, will now assume the role of sole Ariane 5 prime contractor, managing launch campaigns and delivering complete rockets to Arianespace.

EADS officials have said they would like to match their new role with a majority equity stake in Evry, France-based Arianespace. EADS divisions now have a total of about 29 percent. The French space agency, CNES, which has a 32.5-percent stake, has said it is willing to sell all or most of its shares to industry, but will refuse to accept firesale prices.

In its second and presumably last demonstration launch, the Ariane 5 ECA rocket placed U.S. and Indonesian communications satellites into geostationary transfer orbit. Following the successful flight of the same vehicle in February, the Nov. 16 liftoff is expected to ease the concerns of prospective customers and space insurance underwriters about the rocket’s reliability.

Arianespace had insisted that February’s flight should have ended those doubts, but the commercial market was not convinced. Even customers whose satellites would appear to be tailored for Arianespace — such as Telenor of Norway — had shied away from the rocket, saying they needed more proof.

Space insurance underwriters have said that in today’s market, a new rocket needs at least two consecutive successes before it can command insurance rates that are in line with the rest of the industry.

The latest flight carried the Spaceway 2 Ka-band high-definition television broadcast satellite for DirecTV Inc. of El Segundo, Calif., and the Telkom-2 telecommunications spacecraft owned by PT Telkom of Indonesia.

The flight demonstrated what Arianespace can do now that it could not do with the Ariane 5G vehicle it has been using exclusively since the earlier version of the Ariane 5 ECA failed on its inaugural launch in December 2002. It also illustrated why the company’s business model — launching two telecommunications satellites at a time — has suffered in the past three years.

Spaceway 2, a Boeing 702 model spacecraft, weighed 6,116 kilograms at launch. Telkom-2, based on Orbital Sciences Corp.’s Star 2 satellite frame, weighed 1,975 kilograms.

The 8,091 kilograms of total satellite weight was a record for Arianespace, but a record that is likely to be broken in short order.

The Ariane 5 ECA, outfitted with the Vulcain 2 main-stage cryogenic engine and a cryogenic upper stage, is capable of placing about 9,500 kilograms of satellite payload into geostationary transfer orbit, the destination of most commercial telecommunication satellites. The Ariane 5G has a capacity of about 6,500 kilograms.

With the Ariane 5 ECA, Arianespace in most cases will be able to launch the first two satellites that arrive ready to go at Europe’s Guiana Space Center in French Guiana. Up to now the company has been forced to match larger and smaller satellites — and occasionally to launch Spaceway 2-size spacecraft solo — to stay within the Ariane 5G limits.

Arianespace Chief Executive Jean-Yves Le Gall has said the Ariane 5 ECA will permit the company to adopt a “first-come, first-launched” policy. Matching large and small spacecraft as dictated by the payload constraints of the Ariane 5G often meant that one customer was held hostage to the other’s satellite manufacturing schedule. That was the case earlier this year when the launch of a French military communications was delayed for three months when its co-passenger was returned to the factory due to concerns with a component .

Arianespace has been able to hold its own in the market in the past three years in part because of the strong showing of Dulles, Va.-based Orbital Sciences Corp.’s Star small satellite platform, which has captured a share of the commercial market that industry forecasters failed to anticipate.

The presence of the Star geostationary satellites — typically weighing around 2,000 kilograms — on the commercial market permitted Arianespace to enter competitions for the launch of larger satellites on the assumption that it could fill the remaining capacity aboard its Ariane 5G with an Orbital Sciences satellite.

Arianespace officials have said launching satellites one at a time aboard the Ariane 5 is a break-even business at best. The company needs a second satellite to be able to turn a profit.

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