First Launch Since Explosion Last Year Caused Loss Of A Satellite

Sea Launch placed a satellite in orbit, marking a resurrection of the space firm following a disastrous rocket explosion early last year that destroyed a satellite payload.

The Sea Launch win last week marked the end of a long comeback trail for the company, which fires rockets off a sea-going platform that, before each launch, is stationed in the Pacific Ocean near the equator.

In the successful launch, a telephone communications satellite built by The Boeing Co. [BA] for Thuraya Satellite Telecommunications Co. was lifted into orbit by a Sea Launch Zenit-3SL rocket.

Ground crews later received the first signals from the Thuraya-3 Geo-mobile satellite, indicating that it is healthy and operating as designed. A ground station in Fillmore, Calif., successfully acquired signals from the commercial communications satellite approximately 1 hour, 51 minutes after liftoff.

On-orbit check-out will last about 28 days.

Thuraya-3 is the third satellite Boeing has built for Thuraya. Boeing technology has helped Thuraya provide mobile satellite services to more than 110 countries inhabited by 2.3 billion people. Thuraya-3 will expand that service to include markets in Japan, China, Australia and Korea.

Thuraya satellites enable mobile telephone services, transmitting and receiving calls through each satellite’s 12.25-meter-aperture reflector. Calls are routed directly from one handheld unit to another, or to a terrestrial network. The system has the capacity for 25,120 simultaneous voice circuits.

In the accident last year, another Zenit-3SL (No. SL24) rocket exploded at liftoff from the self-propelled Sea Launch platform stationed in the Pacific Ocean.

According to witnesses, the RD-171 engine of the first stage had just ignited, followed by a tilt of the rocket and by the immediate fireball, which completely obscured the vehicle.

No one was injured in the explosion, because personnel were removed from the launch platform to operate it remotely from a distant site.

That Jan. 30 explosion on the launch platform led to a year-long sleuthing effort by panels of experts.

The Sea Launch Failure Review Oversight Board (FROB) finally concluded its review of the findings of an interagency Joint Commission, which probed the cause of the explosion.

All systems were cleared for operations, pending completion and tests of all repairs on the launch platform.

The commission concluded that the failure initiated in the liquid oxygen (LOX) turbopump section of the RD-171M main engine.

Following the initial FROB meeting in April with the commission, the Sea Launch partners performed internal inspections of already manufactured and tested RD-171M engines, with the objective of confirming the LOX feed system and pumps were free of debris.

The FROB met again with the commission, May 24-June 1, to review results of the engine inspections and further findings. FROB Chairman Kirk Pysher, vice president and chief systems engineer for Sea Launch, reported that members of the FROB concurred with the commission findings, conclusions and recommendations, including a conclusion that the anomaly initiated within the RD-171M LOx turbopump as the result of a metallic object becoming lodged between the pump’s moving and stationary components.

Whatever the object was, it ignited and burned as a result of friction-induced heat, and that combustion of the object set off a string of events that led to the destruction of the LOx pump, RD-171M engine and ultimately the Zenit 3SL.

The commission found two operations with the potential for introduction of foreign object debris into the LOX feed system, and then set corrective actions to avert the problem in future missions.