Almost-launched Sealaunch Rocket Needs First Stage Engine Replaced

Almost-launched Sealaunch Rocket Needs First Stage Engine Replaced

Keith Cowing
Tuesday, January 9, 2001

Sealaunch's Zenit-3SL rocket needs to have its first stage engine replaced. Yesterday's attempted launch of a XM-1 satellite aboard a Sealaunch booster was aborted just 15 seconds before engine ignition. According to ITAR-TASS this last minute halt to the launch sequence caused irreversible damage to the Energomash RD-170 engine in the rocket's first stage. The engine will need to be returned to the Energomash facilities in Russia for refurbishing before it can be used again.

Sealaunch has two spare Zenits it could use to launch the XM Radio satellite - one aboard the Sealaunch command ship, the other at the Sealaunch base in California. At least two weeks would be needed to replace the used rocket engine with one taken from the first stage from one of these other two unused rockets.

When launched, the XM-1 satellite will be placed into geosynchronous and is designed to operate for 15 years. The XM-1 satellite is the first of two satellites designed to transmit digital audio radio programming directly to cars, homes and portable radios in the United States. The XM-1 satellite is built by Boeing Satellite Systems and is a 702 model satellite which is the most powerful communications satellite ordered to date.

The Zenit-3SL rocket is 200 feet tall and can place 5,250 kg (11,550 lbs) into geosynchronous transfer orbit. The rocket has three stages - all powered by kerosine and liquid oxygen. Stages 1 and 2 are manufactured by SDO Yuzhnoye/PO Yuzhmash in Dnepropetrovsk, Ukraine. The third stage, a Block DM-SL, is manufactured by RSC Energia in Russia. The Zenit was originally designed as a strap-on booster for the massive Energia booster which launched Russia's space shuttle Buran on its single mission.

Satellites are integrated with Zenit launchers at the Sealaunch home port facility in Long Beach, California. According to Sealaunch "Following the completion of fueling and encapsulation in the payload processing facility, the integrated payload unit is transferred to the assembly and command ship for integration with the launch vehicle. The horizontally integrated rocket is then transferred to the launch platform, where it is stored in an environmentally controlled hangar during transit to the equator." Launches occur in the South Pacific in international waters on the equator at 154° west longitude.