In what has become a continuing run of bad luck for the launch industry, a Titan 4B rocket mission failed to place its military satellite payload in the correct orbit Friday marking the third failed launch attempt in a row for the US Air Force.

The Lockheed Martin-built Titan 4B rocket carried a 10,000-pound Milstar communications satellite for the Air Force on a mission valued at more than $1.2 billion. The satellite alone is worth around $800,000. Both the rocket and the satellite were manufactured by Lockheed.

The Titan 4B lifted off successfully from the Cape Canaveral launch site midday local time, but by early evening it was clear something had gone amiss. Launch officials say the satellite's upper stage booster failed to fire the required three times to raise the satellite into its prescribed 22,300-mile-high orbit.

The Air Force uses the sophisticated Milstar satellites for some of its most sensitive communications. There are currently two of the satellites in orbit being used to transmit secure data such as cruise missile targeting information being used in the Kosovo conflict. The botched launch attempt follows a Titan 4A rocket explosion in August 1998 that destroyed a $750 million spy satellite on board. Just three weeks ago, another defense satellite was placed into the wrong orbit. (See related story)

The latest rocket launch mishap prompted Boeing to announce the delay of its Delta III rocket launch until Tuesday of this week. Boeing said it would wait and assess any potential implications from the failed Titan 4B launch. The Boeing Delta III program has experienced its own series of glitches and technical malfunctions in recent weeks. This postponed Delta III launch, which will carry an Orion 3 communications satellite into orbit, has been delayed four times prior to this incident.

Lockheed has faced other recent rocket failures outside of its Titan program. A Lockheed Martin-built Athena II rocket, launched from Vandenberg Air Force Base on April 27, failed to place the Ikonos 1 satellite it was carrying into orbit. Telemetry and other flight data analysis indicated that the rocket didn't achieve sufficient velocity to place the satellite into orbit. Investigators say the payload fairing didn't separate properly, and the extra weight the rocket was forced to carry caused the failure to reach sufficient velocity.

The Athena II rocket was to have placed the Ikonos 1 into a 423-mile circular orbit above the Earth. This was the fourth Athena mission since the vehicles became operational in 1997. All three prior flights of Athena I and II launch vehicles have been successful.

Lockheed is still investigating to determine why the Athena payload fairing failed to separate properly.