BY SPACEFLIGHT NOW

Follow the preparations and launch of the Arianespace Ariane 4 rocket carrying the Intelsat 905 communications satellite. Reload this page for the very latest on the mission.

WEDNESDAY, JUNE 5, 2002

A communications satellite rescued in space 10 years ago by astronauts aboard space shuttle Endeavour now has a replacement on its way with the successful launch of Intelsat 905 aboard an Ariane rocket. Read full story.

0710 GMT (3:10 a.m. EDT)

Arianespace confirms this morning's launch has gone according to plan, marking the 71st straight success for the Ariane 4 rocket.

We'll have a full wrap-up story later this morning.

0705 GMT (3:05 a.m. EDT)

Plus+21 minutes, 8 seconds. SPACECRAFT SEPARATION! The Intelsat 905 telecommunications satellite has been released into space from the Ariane 4 rocket's third stage, completing this morning's launch of Arianespace Flight 152.

0704 GMT (3:04 a.m. EDT)

Plus+20 minutes. Altitude is 326 km, velocity 9.6 km/sec.

0703 GMT (3:03 a.m. EDT)

Plus+19 minutes 30. Confirmation of third stage shut down, completing the powered phase of flight. Orbit has been achieved. The stage will now provide the necessary pointing for deployment of the Intelsat 905 spacecraft over the next minute.

0702 GMT (3:02 a.m. EDT)

Plus+18 minutes. The Libreville tracking station in Africa has acquired the rocket's signal. Altitude is 218 km, velocity 9.2 km/sec.

0701 GMT (3:01 a.m. EDT)

Plus+17 minutes, 10 seconds. Altitude is 198 km, velocity 8.9 km/sec.

0700 GMT (3:00 a.m. EDT)

Plus+16 minutes, 30 seconds. The rocket has bottomed out in its sling-shot to orbit and is now climbing higher. Vehicle parameters and trajectory reported normal. The altitude is 190 km, velocity 8.6 km/sec.

0659 GMT (2:59 a.m. EDT)

Plus+16 minutes. About three minutes left in the third stage burn. Altitude is 187 km.

0658 GMT (2:58 a.m. EDT)

Plus+14 minutes, 15 seconds. The Ariane rocket continues to gain speed. Altitude is 195 km, velocity 7.7 km/sec.

0656 GMT (2:56 a.m. EDT)

Plus+12 minutes, 30 seconds. The Ascension Island tracking station in the Atlantic Ocean has acquired the rocket's signal as it heads eastward away from South America. Altitude is 212 km, velocity 7.08 km/sec.

0655 GMT (2:55 a.m. EDT)

Plus+11 minutes, 45 seconds. Altitude is 220 km, velocity 6.8 km/sec.

0654 GMT (2:54 a.m. EDT)

Plus+10 minutes, 45 seconds. This is now the period in flight where the Ariane rocket gives up a bit of altitude in order to gain velocity like a sling-shot. Altitude is 228 km, velocity 6.5 km/sec.

0653 GMT (2:53 a.m. EDT)

Plus+9 minutes, 5 seconds. Third stage burn continues. Altitude 230 km, velocity 6.1 km/sec.

0651 GMT (2:51 a.m. EDT)

Plus+7 minutes. The Natal tracking station in Brazil has picked up the rocket's signal as it travels downrange. Vehicle remains on the proper course with system performance reported normal. Altitude is 203 km, velocity 5.6 km/sec.

0650 GMT (2:50 a.m. EDT)

Plus+6 minutes. Burnout of the second stage has occurred and the spent stage has jettisoned. The cryogenic upper stage has now ignited for its long-duration burn to deliver the Intelsat 905 satellite payload into orbit.

0649 GMT (2:49 a.m. EDT)

Plus+5 minutes, 30 seconds. Second stage continues to burn. Altitude is 157 km, velocity 5.28 km/sec.

0648 GMT (2:48 a.m. EDT)

Plus+4 minutes, 30 seconds. The payload fairing has been jettisoned since it is no longer needed to shield the Intelsat 905 spacecraft. Altitude is 123 km, velocity 3.8 km/sec.

0647 GMT (2:47 a.m. EDT)

Plus+3 minutes, 45 seconds. The four first stage main engines have shut down and the spent stage was jettisoned. And the second stage has now ignited.

0647 GMT (2:47 a.m. EDT)

Plus+3 minutes, 15 seconds. Altitude is 72.7 km, velocity 2.7 km/sec.

0646 GMT (2:46 a.m. EDT)

Plus+2 minutes, 45 seconds. The four liquid-propellant strap-on boosters have shut down and separated from the Ariane 4's first stage. The spent casings fall into the Atlantic Ocean. The first stage main engines are still burning to continue the climb to orbit.

0646 GMT (2:46 a.m. EDT)

Plus+2 minutes, 15 seconds. Altitude 33 km, velocity 1.3 km/sec.

0645 GMT (2:45 a.m. EDT)

Plus+1 minute 45 seconds. So far so good in this flight of the Ariane 4 rocket. Altitude 18 km, velocity 0.6 km/sec. Trajectory reported normal. All engines continue to fire as the vehicle streaking into the predawn sky.

0645 GMT (2:45 a.m. EDT)

Plus+75 seconds. Altitude 7.5 km, velocity 0.3 km/sec.

0644 GMT (2:44 a.m. EDT)

Plus+30 seconds. Ariane has pitched to the proper eastward trajectory away from the launch site. The rocket is riding the thrust of eight engines -- four main engines and four liquid-fueled strap-on boosters.

0644 GMT (2:44 a.m. EDT)

LIFTOFF! Liftoff of the Ariane 4 rocket and the fifth spacecraft in Intelsat's newest generation of communications spacecraft. And the vehicle has cleared the tower!

0643 GMT (2:43 a.m. EDT)

Minus-1 minute. Equipment aboard the Ariane 44L rocket is being switched off ground-supplied power and to onboard batteries for launch.

In the final seconds of the countdown, activities will include releasing the inertial platform at minus 9 seconds, and the release command to the retraction system for the two cryogenic arms will be given at Minus-5 seconds.

0642 GMT (2:42 a.m. EDT)

Minus-2 minutes and counting. The third stage liquid oxygen tank has been pressurized for the launch.

0640 GMT (2:40 a.m. EDT)

Minus-4 minutes and counting. The launch team is monitoring the final topping off of liquid oxygen and liquid hydrogen supplies aboard the rocket's third stage.

In the next half-minute, the launch time will be loaded aboard the Ariane rocket's guidance system. Also, the Intelsat 905 spacecraft will be confirmed on internal power and declared ready for launch.

0638 GMT (2:38 a.m. EDT)

Minus-6 minutes and counting. Arianespace says the issue, whatever it was, has been resolved. So the synchronized launch sequence has started. Computers are now in control of this final portion of the launch countdown. Liftoff is set for 0644 GMT (2:44 a.m. EDT).

During the next six minutes, the Ariane 44L rocket, satellite payload and ground systems will be configured for launch. There are two master computers running the countdown. One is responsible for fluids and propellants and the other for final preparation of the electrical systems such as initiating the flight program, activation of the engine steering systems and power transfer from ground supplies to onboard batteries. The computers will control until minus 5 seconds when a majority logic sequencer takes over for first stage engine and liquid strap-on booster start at zero seconds. Engine performance checks are done in parallel by the two computers starting at plus 2.8 seconds. Finally, the command will be issued to open the launch table clamps for liftoff between ignition +plus 4.4 and 4.6 seconds.

0637 GMT (2:37 a.m. EDT)

Minus-7 minutes. The status panel in the control center remains all green, including confirmation that the weather is "go" for launch.

0634 GMT (2:34 a.m. EDT)

Minus-10 minutes and counting. A network of tracking stations are standing ready to relay data from the Ariane 4 rocket to engineers in Kourou. The early portion of flight will be monitored through the Kourou and Cayenne stations in French Guiana. About 6 minutes, 30 seconds into flight the Natal station in Brazil will pick up the rocket's signal as the third stage burn gets underway. At T+plus 12 minutes, 30 seconds the site on Ascension Island in the Atlantic Ocean will begin coverage. Libreville in Gabon will provide services beginning at T+plus 17 minutes, 30 seconds for spacecraft separation and the conclusion of Arianespace Flight 152.

0629 GMT (2:29 a.m. EDT)

Minus-15 minutes. The three-stage rocket is set to deliver the Intelsat 905 satellite into a geosynchronous transfer orbit of approximately 200 km on the low end and 35,956 km on the high end, with an inclination of 7 degrees. Ariane 4 is going for its 71st consecutive successful launch.

0624 GMT (2:24 a.m. EDT)

Minus-20 minutes and counting down to this morning's predawn launch of the Ariane 44L rocket with the Intelsat 905 communications spacecraft.

The three-stage rocket has been fully fueled and prepared for liftoff at 0644 GMT from the ELA-2 pad at the Guiana Space Center in South America.

Launch team members are watching systems on the Ariane 4 rocket, the spacecraft and ground support equipment. There are no problems being reported. The status panel in the Jupiter control center green across the board, indicating all systems are "go" at this time.

0401 GMT (12:01 a.m. EDT)

The Ariane 4 rocket's third stage is being loaded with super-cold cryogenic liquid hydrogen and liquid oxygen as the countdown continues for this morning's launch. The first two stages were fueled with storable rocket propellants earlier this week. Liftoff is scheduled to occur at 0644 GMT (2:44 a.m. EDT).

TUESDAY, JUNE 4, 2002

An advanced communications satellite is awaiting launch from the jungles of South America early Wednesday to replace the aging Intelsat spacecraft that space shuttle astronauts rescued 10 years ago.

Launch is scheduled for the opening of an hour-long launch window at 0644 GMT (2:44 a.m. EDT) from the ELA-2 launch pad at Kourou, French Guiana.

Flight 152 will fly in the Ariane 44L configuration with four liquid-fueled boosters to augment the launcher's thrust early in the flight. The flight will mark the 152nd Ariane launch overall, the 111th mission of an Ariane 4, and the 37th use of an Ariane 44L. After this launch, just three more Ariane 4 rockets remain to be flown before they are phased out in favor of the Ariane 5 launch vehicle.

Sitting inside the Ariane rocket's payload fairing is the Intelsat 905 communications satellite, destined to replace the Intelsat 603 craft that was repaired in orbit by astronauts aboard space shuttle Endeavour's maiden flight in May 1992. Intelsat 603 was left stranded in a useless low orbit after a botched launch by a Titan 3 rocket in 1990 from Cape Canaveral.

Intelsat 905 is the fifth in the newest series of Intelsat's fleet of communications satellites that serve customers around the world. This newest addition will be positioned in a circular geostationary orbit 22,300 miles above a point on the equator at 24.5 degrees West, or over the Atlantic Ocean. From that vantage point, the satellite's compliment of C-band and Ku-band transponders will reach users in the Americas, Europe, Africa, and the Middle East. Intelsat 905 will provide Internet, broadcasting, telephone, and networking services for Intelsat customers.

Built by Space Systems/Loral of Palo Alto, California, Intelsat 905 is expected to operate in orbit for at least 13 years. The craft weighs in at 10,390 pounds at liftoff, and features solar panels that will stretch almost 100 feet from tip-to-tip when fully deployed in space.

Processing for Flight 152 began on April 25 with the placement of the rocket's first stage onto the mobile launch table. Stacking of the second stage followed the next day. The four liquid boosters were added from April 29 to May 6, when the launcher's third stage was added.

The Flight 152 payload arrived in Kourou for final preparations on May 2. Fueling of Intelsat 905 began on May 14.

The nearly-complete Ariane 44L rocket was rolled from the launcher integration building to the ELA-2 launch zone on May 22.

Intelsat 905 was placed inside the Ariane's payload fairing on May 27, and was transported to the launch pad the next day. Attachment of the payload to the launcher occurred on May 29.

The launch team took part in a launch rehearsal last Thursday to hone their skills one final time prior to the real countdown on Tuesday and Wednesday.

On Friday, senior officials conducted a launch readiness review to ensure that all was ready for launch. Once a final "go" was agreed upon, workers began connecting pyrotechnics to the launcher.

Fueling of the rocket's first stage, second stage, and four liquid-fueled boosters with their load of unsymmetrical dimethyl hydrazine and nitrogen tetroxide took place on Monday.

Looking ahead to the milestone events in Tuesday and Wednesday's countdown, the final countdown will get underway at 1814 GMT (2:14 p.m. EDT) on Tuesday. The protective mobile service gantry will begin to be rolled back into launch position at 0109 GMT Wednesday (9:09 p.m. EDT Tuesday). At 0309 GMT Wednesday (11:09 p.m. EDT Tuesday), super-cold liquid hydrogen and liquid oxygen will begin flowing into the Ariane 4's cryogenic third stage. The launcher's telemetry, telecommand, and radar transponder systems will be activated at 0539 GMT (1:39 a.m. EDT). If all parameters are determined to be "go", computers will take control of the countdown when the synchronized launch sequence begins 6 minutes prior to launch. Following this key milestone is a series of fast-paced events that will culminate with the ignition of the Viking engine powerplants on the rocket's first stage and four boosters.

Following liftoff, Flight 152 will take a standard Ariane 44L ascent profile with two minute, 30 second burns of all four boosters. The first stage will burn for three minutes, 30 seconds, then it will shut off and separate. The Ariane 4's second stage will then ignite and fire for two minutes, during which time the payload fairing will be jettisoned. The third stage is then expected to come to life and burn for 13 minutes before cutting off in preparation for spacecraft separation, which is supposed to occur 21 minutes after launch.

Stay with Spaceflight Now for live play-by-play coverage of the countdown and launch early Wednesday.