PARIS — Europe’s Arianespace launch consortium is ready to add one or two Ariane 5 launches to its 2014 manifest if commercial customers make themselves known quickly enough, the Evry, France-based company said July 2.

In response to SpaceNews inquiries following the failure of a Russian Proton rocket, Arianespace said it still has time to order as many as two additional heavy-lift Ariane 5 vehicles for launch in 2014.

Russia’s Proton, marketed commercially by International Launch Services (ILS) of Reston, Va., is the biggest competitor to Ariane 5 for launching satellites in the 6,000-kilogram weight class.

The July 2 Proton launch carried three Russian government Glonass navigation satellites and was not managed by ILS. 

But the failure, which occurred just seconds after liftoff, nonetheless is likely to ground all Proton missions until a root cause is determined. That could leave an opening for Arianespace to fill the Ariane 5 vehicle’s upper position with one or two satellites whose owners cannot afford to wait for Proton’s return to flight.

ILS had tentatively planned to launch up to four more commercial missions in 2013 — the SES Astra 2E, the Sirius XM Radio FM6, the first of three Inmarsat 5/Global Xpress satellites, and the Turksat 4A spacecraft. 

Most Ariane 5 flights need a lighter satellite to fill the rocket’s bottom slot, and for this class of satellite Arianespace is eyeing delays in the debut of the upgraded Falcon 9 rocket for possible 2014 customers.

Space Exploration Technologies Corp. (SpaceX) of Hawthorne, Calif., is expected to debut the new Falcon 9 this summer before moving to commercial launches of telecommunications satellites operating in geostationary orbit.

SpaceX has scheduled seven commercial launches to geostationary orbit in 2013 and 2014 aboard the upgraded Falcon 9. SES of Luxembourg and Thaicom of Thailand are the first two of these customers, both slotted for 2013 launches whose dates have not been finalized.

Arianespace itself has not yet determined its launch manifest for late this year and 2013, in part because it was not certain of the actual arrival date of satellite customers to Europe’s Guiana Space Center in French Guiana.

Arianespace launched seven Ariane 5 vehicles in 2012 but currently plans to launch only five in 2013, with the possibility of a sixth.

The company’s launch preparations have become complicated because it must not only match two arriving satellites to Ariane 5 missions, but also juggle the launch schedules of the medium-lift Europeanized version of Russia’s Soyuz rocket, which launches from the European spaceport and the smaller Vega rocket.

Peter B. de Selding was the Paris Bureau Chief for SpaceNews.