Spaceflight Now: Mission Report

Europe's Ariane 4 rocket carries out military mission
Posted: February 7, 2001

Ariane 4 rocket lifts off. Photo: Arianespace TV
Arianespace launched its first double military payload Wednesday, lofting a pair of communications relay satellites for the British and Italian defense ministries.

Liftoff occurred at about 2306 GMT (6:06 p.m. EST) from the Guiana Space Center in Kourou, French Guiana.

The Ariane 44L rocket had to wait an extra 38 minutes or so before launching while controllers resolved a telemetry problem with the United Kingdom's Skynet 4F spacecraft atop the launcher. Then satellite managers with the co-payload, Italy's Sicral 1, had to reset the craft's internal timing to reflect the delayed liftoff time.

But after the issues were wrapped up, the countdown resumed from Minus-6 minutes and proceeded to blastoff. The three stage rocket, also sporting with four liquid-fueled strap-on boosters, soared into the South American night sky and headed eastward across the Atlantic.

Less than 26 minutes later, the two satellites were deployed into a highly elliptical geosynchronous transer orbit. They will fire onboard kick engines later to achieve geostationary orbit 22,300 miles above the equator.

"For the first time in its history, Ariane has orbited two European military communications satellites on a single mission," said Jean-Marie Luton, Arianespace chairman and CEO. "This is concrete proof that the Ariane system has met the political and strategic goal set back in 1973, of giving Europe independent access to space."

An artist's concept of Sicral. Photo: Alenia Aerospazio
Sicral 1 is the first military satellite for the Italian Defense Ministry.

The launch of Sicral activates the new network for military air, land and sea telecommunications. Its high performance puts Italy in a leading position in European space, offering efficient and timely telecommunications in any operational conditions -- emergencies, humanitarian missions or peacekeeping.

In the event of natural catastrophes too, Sicral can make up for deficiencies in terrestrial fixed and mobile networks for a better planning and co-ordination of aid.

Leading the satellite program was the Italian consortium Sitab, including Alenia Aerospazio for the satellite, FiatAvio for propulsion systems and launch operations, and Telespazio for the ground segment.

Sicral carries 9 SHF, UHF and EHF transponders. It will be positioned at 16.2 degrees East.

Skynet 4F will relay strategic and tactical communications between British troops, including peacekeepers in the Balkans, for the U.K. Ministry of Defence.

Skynet 4F
An artist's concept of Skynet 4F. Photo: Astrium
A variety of spot and global beams enables the satellite to serve a widely dispersed and extensive inventory of Earth stations on land, sea and in the air, ranging from small man-portable radio sets and aircraft terminals to rugged systems on naval vessels and submarines and the large anchor stations on land.

Skynet 4F employs signal processing and anti-jamming features and its ability to survive in the harshest of electronic warfare environments is extremely important.

The craft, built by Astrium in Stevenage, U.K., is equipped with eight SHF, UHF and S-band transponders. It will be positioned at either 1 degree West or 6 degrees East.

Wednesday's launch marked the 61st consecutive successful Ariane 4 flight, a world record in the commercial space industry.

Arianespace's next launch is scheduled for early March 2 when the Ariane 509 rocket lifts off with carry Eutelsat's Eutelsat and the Japanese BSAT-2a commercial telecommunications spacecraft.

Following Flight 139, Arianespace's backlog now stands at 46 contracts: 37 satellites to be launched, plus 9 ATV missions for the international space station.

Flight data file
Vehicle: Ariane 44L
Payload: Sicral 1 & Skynet 4F
Launch date: Feb. 7, 2001
Launch window: 2228-2328 GMT (5:28-6:28 p.m. EST)
Launch site: ELA-2, Kourou, French Guiana
Satellite broadcast: Telstar 5, Transponder 16, C-band

Pre-launch Briefing
Launch timeline - Chart with times and descriptions of the events to occur during launch.

Ariane 44L - Overview of the rocket configuration for this launch.

Ariane directory - See our previous coverage of Ariane rocket launches.