Artist's concept of an Atlas 3A rocket launching into space. Photo: Lockheed Martin.

The maiden flight of Lockheed Martin's new Atlas 3A rocket has been postponed from April 14 to mid-May because of concerns with the European satellite it will carry into space.

Officials said Wednesday that technical issues have emerged during pre-launch preparation for the European Telecommunications Satellite Organization's W4 spacecraft, causing the flight to be delayed. The Atlas 3A rocket remains assembled atop pad 36B at Cape Canaveral Air Force Station, Florida.

"In accordance with Eutelsat's policy, as a commercial satellite operator, of providing its clients with the highest quality of service, an additional series of tests will be carried out by industry on part of the equipment installed on W4's propulsion system," the company said in a statement. "This measure has been decided in order to ensure full confidence in the performance of the satellite throughout its expected 12-year lifetime."

Once in space, W4 will be positioned in geostationary orbit 22,300 miles above Earth to relay digital television programming and provide Internet access to Russia and sub-Saharan Africa. Alcatel Space Industries of Cannes, France built the satellite.

Meanwhile, Lockheed Martin says the extra month will also allow its engineers to conduct further tests of the rocket's Centaur upper stage venting system. The checks to be made involve the "interface loads on the duct of the Centaur upper stage's overboard vent system."

The new Atlas 3 will join Lockheed Martin's existing Atlas 2 line of rockets. The company developed the more powerful Atlas 3 to launch heavier satellites into space than the current Atlas 2 boosters can handle.

Atlas 3 fleet will also serve as evolutionary step toward the next-generation Atlas 5 rocket family, of which both programs with use the new Russian-built RD-180 engine.

Lockheed Martin originally planned to launch its first Atlas 3 last summer. However, engine concerns delayed the flight and the satellite cargo -- Loral's Telstar 7 -- was pulled in favor of launching on the rival Arianespace Ariane 4 rocket.

The first Atlas 3 rocket, known as AC-201, was removed from its launch pad after the loss of Telstar 7 and placed in storage. The rocket was reassembled at pad 36B in February.

The delay means the next Atlas launch will be AC-137 carrying the advanced U.S. GOES-L weather satellite for NASA and NOAA on May 3. The Atlas 2A rocket and its Centaur upper stage are being stacked on pad 36A this week.