BY SPACEFLIGHT NOW WRITERS

December 20, 2000 -- Follow the preparations and launch of the Arianespace Ariane 508 rocket carrying the Astra 2D and GE-8 communications satellites. Reload this page for the very latest on the mission.

WEDNESDAY, DECEMBER 20, 2000

Arianespace punctuated its 2000 launch season Tuesday evening with the successful flight of the eighth Ariane 5 rocket, lofting a pair of communications spacecraft to serve the United Kingdom and North America and testing an experimental Japanese antenna design. Read our complete launch story.

0124 GMT (8:24 p.m. EST, Tues.)

Plus+58 minutes. Arianespace's commentary from Kourou has signed off. Confirmation of deployment of the LDREX antenna and subsequent separation from the upper stage isn't expected until later tonight.

We will pause our coverage now. Look back later for a full wrap-up report.

0119 GMT (8:19 p.m. EST)

Plus+53 minutes. Japanese space officials report the antenna deployment command was issued and the LDREX experiment has started. It will take 20 minutes for the six-meter antenna reflector structure to fully deploy.

0116 GMT (8:16 p.m. EST)

Plus+50 minutes. There have not been any reports from Arianespace on the status of the LDREX deployment. Once the antenna is fully unfurled, it will separate from the Ariane 5 rocket to complete Arianespace's Flight 138 over the next 15 minutes.

0107 GMT (8:07 p.m. EST)

Plus+41 minutes. The Large-scale Deployable Reflector Experiment should be underway. Stretching six meters in diameter, the antenna is being deployed from a tube-like container mounted to the Ariane 5 rocket's upper stage. This experiment is testing a half-sized antenna of the design to be used by Japan's ETS-8 communications testbed satellite.

0101 GMT (8:01 p.m. EST)

Plus+35 minutes. The Ariane 5 rocket's upper stage is now a platform for the upcoming deployment test of Japan's Large-scale Deployable Reflector Experiment (LDREX). A 20-minute deployment of this massive antenna will begin in about five minutes.

0100 GMT (8:00 p.m. EST)

Plus+34 minutes. GE-8 SEPARATION! GE Americom's GE-8 spacecraft, also known as Aurora 3, has separated from the Ariane 5 rocket. The craft, built by Lockheed Martin, will provide television, radio and telephone communications services to the United States and focused coverage to remote areas of Alaska.

0059 GMT (7:59 p.m. EST)

Plus+33 minutes. Standing by for release of the GE-8 spacecraft.

0057 GMT (7:57 p.m. EST)

Plus+31 minutes, 30 seconds. The Sylda 5 structure has separated from the Ariane 5. This barrel-like adapter held the Astra 2D during launch and enclosed the GE-8 spacecraft. GE-8 is now free for deployment in about three minutes.

0056 GMT (7:56 p.m. EST)

Plus+30 minutes. Altitude 2706 km, velocity 7.87 km/sec. The next event in tonight's launch will be the jettisoning of the Sylda 5 dual payload adapter from the Ariane 5 rocket in about a minute.

0054 GMT (7:54 p.m. EST)

Plus+28 minutes, 40 seconds. ASTRA 2D SEPARATION! The direct-to-home television broadcasting satellite Astra 2D satellite has been released into space from the Ariane 5 rocket. The satellite, built by Boeing, features 16 transponders that will serve the United Kingdom for operator Societe Europeenne de Satellites (SES).

0053 GMT (7:53 p.m. EST)

Plus+27 minutes. Confirmation that the upper stage has shutdown as planned to complete powered flight for the launch. The stage will now spin up to 5 rpm and provide proper pointing for deployment of the Astra 2D and GE-8 primary payloads.

0052 GMT (7:52 p.m. EST)

Plus+26 minutes. Coming up on shutdown of the upper stage engine. Altitude 1780 km, velocity 8.39 km/sec.

0051 GMT (7:51 p.m. EST)

Plus+25 minutes. Altitude 1579 km, velocity 8.38 km/sec.

0050 GMT (7:50 p.m. EST)

Plus+24 minutes. Less than three minutes left in the propulsion from the upper stage. Altitude 1395 km, velocity 8.37 km/sec.

0049 GMT (7:49 p.m. EST)

Plus+23 minutes. Altitude 1220 km, velocity 8.35 km/sec. The Malindi tracking station in Kenya, Africa, has acquired the Ariane 5 rocket's signal.

0048 GMT (7:48 p.m. EST)

Plus+22 minutes. Altitude is 1069 km, velocity is 8.33 km/sec.

0047 GMT (7:47 p.m. EST)

Plus+21 minutes. Altitude is 933 km, velocity is 8.31 km/sec.

0046 GMT (7:46 p.m. EST)

Plus+20 minutes. Now twenty minutes since launch. About seven minutes left to go in the upper stage burn.

0045 GMT (7:45 p.m. EST)

Plus+19 minutes. Arianespace reports the rocket systems are performing normally and the trajectory is per the plan. Altitude is 703 km, velocity is 8.25 km/sec.

0044 GMT (7:44 p.m. EST)

Plus+18 minutes, 10 seconds. A smooth flight of the Ariane 508 launcher continues above the central Atlantic Ocean. Altitude is 624 km, velocity is 8.2 km/sec.

0043 GMT (7:43 p.m. EST)

Plus+17 minutes. The rocket has passed out of range from the Natal tracking station. Altitude is 526 km, velocity is 8.1 km/sec.

0041 GMT (7:41 p.m. EST)

Plus+15 minutes, 30 seconds. About 12 minutes left in the long-duration burn of the Ariane 5 rocket's upper stage. Altitude is 425 km, velocity is 8.0 km/sec.

0040 GMT (7:40 p.m. EST)

Plus+14 minutes. Altitude is 343 km, velocity is 7.9 km/sec.

0038 GMT (7:38 p.m. EST)

Plus+12 minutes, 35 seconds. The upper stage continues to fire. No problems have been reported. Also, the Ascension Island tracking station in the mid-Atlantic Ocean has picked up signals from the Ariane 508 rocket. Altitude currently 276 km, velocity is 7.9 km/sec.

0037 GMT (7:37 p.m. EST)

Plus+11 minutes, 35 seconds. The vehicle has begun gaining altitude again. Altitude currently 238 km, velocity is 7.6 km/sec.

0036 GMT (7:36 p.m. EST)

Plus+10 minutes, 10 seconds. The main cryogenic stage's Vulcain engine has cut off and the stage has separated. The engine consumed 160 tons of liquid oxygen and liquid hydrogen during the launch. It will fall back into the atmosphere over the Galapagos Islands in the Pacific Ocean. The upper stage, the storable propellant stage, has ignited to deliver the Astra 2D and GE-8 spacecraft and LDREX secondary payload into orbit.

0035 GMT (7:35 p.m. EST)

Plus+9 minutes, 30 seconds. The vehicle has passed out of range from the Kourou tracking station. Less than 30 seconds left in the rocket's main cryogenic stage burn.

0034 GMT (7:34 p.m. EST)

Plus+8 minutes, 30 seconds. The Natal tracking station has acquired signal from the Ariane 5 rocket.

0034 GMT (7:34 p.m. EST)

Plus+8 minutes. Now in the period of flight were the rocket's altitude levels out in order to gain speed. Altitude currently 162 km, velocity is 5.4 km/sec.

0032 GMT (7:32 p.m. EST)

Plus+6 minutes, 30 seconds. Ariane 5 remains on the proper trajectory, all parameters are normal. Altitude is 164 km, velocity 4.0 km/sec.

0031 GMT (7:31 p.m. EST)

Plus+5 minutes, 30 seconds. Altitude is 160 km, velocity is 3.4 km/sec.

0030 GMT (7:30 p.m. EST)

Plus+4 minutes, 30 seconds. The Ariane 508 rocket continues to operate normally and remains on the proper course. Altitude is 143 km, velocity is 2.7 km/sec.

0029 GMT (7:29 p.m. EST)

Plus+3 minutes, 30 seconds. The protective payload fairing has been separated from the Ariane 5. The vehicle now weighs 20 percent of what it did at liftoff. Altitude is 118 km, velocity is 2.4 km/sec.

0028 GMT (7:28 p.m. EST)

Plus+2 minutes, 35 seconds. The solid rocket boosters have been jettisoned from the Ariane 5 rocket's core stage. The boosters provided 90 percent of the liftoff thrust. The liquid-fueled Vulcain main engine continues to fire to propel the vehicle and its cargos to orbit.

0028 GMT (7:28 p.m. EST)

Plus+2 minutes, 20 seconds. Altitude is 67 km, velocity is 2.0 km/sec.

0027 GMT (7:27 p.m. EST)

Plus+1 minute, 40 seconds. Altitude is 30 km, velocity is 1.27 km/sec.

0027 GMT (7:27 p.m. EST)

Plus+1 minute. All vehicle systems reported normal as the Ariane 5 streaks skyward.

0026 GMT (7:26 p.m. EST)

Plus+30 seconds. Rocket has completed its pitch and rolls maneuvers as it heads downrange into a cloudy South American night sky.

0026 GMT (7:26 p.m. EST)

LIFTOFF! Liftoff of the fifth commercial flight of Europe's next-generation Ariane 5 rocket.

0025 GMT (7:25 p.m. EST)

Minus-40 seconds. Vehicle now on internal power.

0025 GMT (7:25 p.m. EST)

Minus-1 minute. A fast-paced series of events leading to launch will begin at Minus 37 seconds when the automated ignition sequence is started. The water suppression system at the launch pad will start at Minus 30 seconds. At Minus 22 seconds, overall control will be given to the onboard computer. The Vulcain main engine will be readied for ignition with hydrogen chilldown starting at Minus 18 seconds. The residual hydrogen burn flares will fire beneath the Vulcain engine at Minus 7 seconds to burn away any free hydrogen gas. At Minus 3 seconds, onboard systems take over and the two inertial guidance systems go to flight mode. Vulcain main engine ignition occurs at Minus 0 seconds with checkout between Plus+4 and 7 seconds. If there are no problems found, the solid rocket boosters are ignited at Plus+7.3 seconds.

0023 GMT (7:23 p.m. EST)

Minus-3 minutes. All systems remain "go" for liftoff. The scheduled launch time has been loaded into the rocket's main computer system. Main stage tank pressures now at flight level.

0022 GMT (7:22 p.m. EST)

Minus-4 minutes. Pressurization now underway for the main cryogenic stage's liquid oxygen and hydrogen tanks. Also, final pyrotechnic arming has started. Liftoff remains planned for 0026 GMT (7:26 p.m. EST).

0021 GMT (7:21 p.m. EST)

Minus-5 minutes and counting. The Ariane 508 rocket's payload weighs in at 3,611 kg (7,944 pounds).

0019 GMT (7:19 p.m. EST)

Minus-7 minutes and counting. Synchronized Sequence start. Computers are now in control of this final segment of the launch countdown to prepare the rocket and ground systems for liftoff. There are two computers running the countdown -- one aboard the Ariane 5 and a redundant one at the ELA-3 launch complex.

0017 GMT (7:17 p.m. EST)

Minus-9 minutes and counting. The Synchronized Sequence will begin in the next two minutes to control the countdown through liftoff.

The final weather update has verified that conditions will be acceptable for launch tonight at 0026 GMT.

0015 GMT (7:15 p.m. EST)

Minus-11 minutes and counting. All systems remain "go" for launch and the status board in the control center is completely green. At the ELA-3 launch zone, the Ariane 508 rocket is poised for liftoff with powerful flood lights illuminating the mighty launcher.

0011 GMT (7:11 p.m. EST)

Minus-15 minutes. Today's launch will be the 137th for an Ariane rocket, the 12th of 2000 and the eighth of Ariane 5.

0009 GMT (7:09 p.m. EST)

Minus-17 minutes and counting. A network of tracking stations are standing ready to relay data from the Ariane 5 rocket to engineers in Kourou. The early portion of flight will be monitored through the Kourou and Cayenne stations in French Guiana. About 8 minutes, 50 seconds into flight the Natal station in Brazil will pick up the rocket's signal as the main stage separates and the upper stage burn gets underway. At Plus 12 minutes, 51 seconds the site on Ascension Island in the Atlantic Ocean will begin coverage. Malindi in Africa will provide services starting at Plus 22 minutes, 06 seconds through the spacecraft separation.

0006 GMT (7:06 p.m. EST)

Minus-20 minutes and counting. The countdown is proceeding on schedule for launch of Ariane 508 with the Astra 2D and GE-8 communications spacecraft and LDREX antenna deployment experiment. There are no technical problems being worked, weather conditions are acceptable and liftoff remains on target for 0026 GMT.

TUESDAY, DECEMBER 19, 2000
2356 GMT (6:56 p.m. EST)

Now 30 minutes away from the scheduled blastoff time for the eighth Ariane 5 rocket. Arianespace will begin providing countdown status reports from the Guiana Space Center in Kourou, French Guiana, starting in about 10 minutes.

At this point in the countdown the rocket should be fully fueled with the main cryogenic stage being continuously topped off to replace the liquid oxygen and liquid hydrogen supplies that naturally boil away. Also, the final checks of the rocket's telemetry, tracking and command systems are supposed to be finished by now.

2145 GMT (4:45 p.m. EST)

The final hours of the launch countdown are ticking away in Kourou as Arianespace prepares for tonight's blastoff of an Ariane 5 rocket. The vehicle has been fueled and the status panel in the Jupiter control center is all green, indicating "go" conditions. Liftoff remains set for 0026 GMT (7:26 p.m. EST) tonight. We will have live reports!

0501 GMT (12:01 a.m. EST)

The European Ariane 508 rocket is sitting on its South American launch pad and awaiting liftoff with two communications satellites and an experimental technology demonstration from the Amazon jungle of French Guiana. Flight 137 will be the 12th and final Ariane launch of the year.

If all goes according to plan, the Ariane 5 launcher will be sent skyward at 0026 GMT (7:26 p.m. EST), the opening of a 43-minute window.

Since our last update, the Ariane 508 launch vehicle was rolled out along dual rail tracks on Monday from the final assembly building to the ELA-3 launch pad. This short pad stay time is available because of the design of both the launch pad and the Ariane 5 rocket.

Encapsulated inside of the rocket's payload fairing are two commercial telecommunications satellites and an experimental package for Japan's space agency -- NASDA.

The Boeing-built Astra 2D communications satellite will provide direct-to-home broadcasting services for the Societe Europeenne de Satellites (SES), a European company that operates the continent's leading direct-to-home satellite system. Ordered in August 1999, the cylindrical craft, which is based on the venerable Boeing 376 bus design, will use 16 Ku-band transponders for an expected 12 years to deliver its services to the United Kingdom.

"Boeing Satellite Systems is proud of its long and positive relationship with SES," said Tig H. Krekel, President of California-based Boeing Satellite Systems. "We've built seven of the ten Astra spacecraft currently in orbit, and we are building two more satellites right now for SES as well. We're equally proud to see Astra 2D preparing for launch."

Krekel went on to say, "this Boeing 376 spin-stabilized spacecraft is one of the most reliable and most purchased commercial communications satellite models in the world."

SES' 11th satellite in its constellation will be positioned at 28.2 degrees East along the Equator, or 22,300 miles above central Africa. At launch, the spacecraft will weigh in at 3,186 pounds. Once in its final operational orbit, the satellite will have a mass of 1,816 pounds. When fully deployed, the spacecraft will be over 26 feet tall and around 7 feet in diameter.

American satellite operator GE Americom's new GE-8 spacecraft and its 24 C-band transponders will provide cable services, broadcast television and radio, business television and broadband data distribution, and other various telecommunications services to all 50 states of the United States and the Caribbean. This will be accomplished in along with other satellites in GE Americom's fleet during GE-8's scheduled 15 years of services.

The Lockheed Martin Commercial Space Systems-built GE-8 will weigh 4,433 pounds at launch time tonight, but that weight will be drastically reduced after using a large amount of propellant when transitioning from its transfer orbit to its operational orbit, thus reducing the on-orbit mass to 2,022 pounds. When the craft's solar arrays are deployed in the satellite's final orbital perch at 139 degrees West, they will extend almost 45 feet tip-to-tip.

Perhaps the most dramatic part of Flight 138 will occur when the Large-scale Deployable Reflector Experiment (LDREX) completes its 20-minute mission while still attached to the ASAP-5 multiple payload deployment adapter of the Ariane 5.

The large reflector to be deployed on LDREX, which was built by Toshiba for NASDA (the Japanese space agency), is actually a half-scale model of a reflector to be used on the upcoming ETS-8 technology demonstration communications satellite. An on-board camera that is mounted to the spacecraft will take images of the deployment that will be downlinked to Earth a few days after launch. That, along with live telemetry data, will validate the design of the reflector to be used on ETS-8.

LDREX's reflector is composed of seven hexagon-shaped modules and will feature a diameter of just over 7 feet at the start of deployment. Each module is composed of very fine mesh-like material. Once fully deployed, the reflector will span over 20 feet, half the size of ETS-8's reflector.

LDREX's slow-paced 20-minute deployment sequence will begin just over 40 minutes into Arianespace Flight 138. Shortly after deployment is completed, the LDREX spacecraft will separate from the ASAP-5 multiple payload structure.

Looking ahead to Tuesday's major pre-launch events, the final countdown will begin at 1526 GMT (10:26 a.m. EST). A check of electrical systems on the Ariane 508 rocket will be performed at 1656 GMT (11:56 a.m. EST). The main cryogenic first stage will start to be fueled with its combination of liquid hydrogen and liquid oxygen propellant at 1906 GMT (2:06 p.m. EST). Chilldown of the first stage's Vulcain main engine will be started by running super-cold liquid hydrogen through fuel lines at 2106 GMT (4:06 p.m. EST). A final check of connections between the launcher, telemetry, tracking, and command systems will be conducted at 2311 GMT (6:11 p.m. EST). If all reporting elements are deemed "go," the synchronized launch sequence will commence at 0019:30 GMT (7:19:30 p.m. EST). Following are a series of fast-paced events culminating with the ignition of the liquid-fueled Vulcain main engine at T-0. The twin solid-fueled boosters will ignite seven seconds later, followed immediately by lift-off.

The Ariane 508 will take a normal Ariane 5 ascent profile with a near three-minute burn of the two solid rocket boosters. The main cryogenic stage will burn for nine minutes, followed by a continuous eighteen-minute burn of the storable propellant upper stage.

Stay with Spaceflight Now for play-by-play updates throughout the launch of Flight 138, starting around 30 minutes prior to launch.

SUNDAY, DECEMBER 17, 2000

A mighty Ariane 5 rocket has taken center stage at the European spaceport in Kourou, French Guiana, where satellite troubles have sidelined an Ariane 4 launcher once poised for blastoff a week ago. Workers are now gearing up to launch a pair of communications satellites and a crucial Japanese experiment Tuesday evening on the Ariane 508 vehicle.

Launch of Arianespace's Flight 138 is targeted for 7:26 p.m. EST (0026 GMT Wednesday), the beginning of a 43-minute window, from the Guiana Space Center's ELA-3 pad.

The Ariane 508 rocket will carry the European Astra 2D and American GE-8 spacecraft and Japanese LDREX antenna test payload.

SES' Astra 2D will broadcast direct to home television to users across Europe for at least 12 years using its 16 active Ku-band transponders. The cylindrical spacecraft is based on Boeing Satellite Systems' Boeing 376 design and will be positioned in geostationary orbit 22,300 miles above Africa.

GE Americom's GE-8 was built by Lockheed Martin as an all C-band spacecraft that will provide telecommunications services throughout North America, Alaska, and Hawaii during its 15 years of service from a perch high above the Pacific Ocean.

The Japanese space agency's Large-scale Deployable Reflector Experiment (LDREX) will operate for all of 20 minutes during the latter part of the Ariane 5's mission. That is how long it will take to deploy its half-scale model of a large deployable antenna to be used on a future Japanese technology satellite. A camera aboard the 400-pound satellite will record the event on video, which will be transmitted to Earth later.

Launch preparations for Flight 138 began on November 2 with the campaign start review to kick-off the unusually long launch campaign. That was tailed on November 3 by the lifting of the main cryogenic first stage into place atop the mobile launch table.

The twin solid-fueled boosters were transferred from their separate processing facility into the launcher integration building on November 7. Both were locked into place alongside the first stage the following day.

The storable propellant upper stage was placed atop the main cryogenic first stage on November 14. The vehicle equipment bay, commonly referred to as the "brains" of the rocket, was lifted above the second stage later the same day.

Both the GE-8 and LDREX payloads for Flight 138 began their respective processing flows on November 20. That milestone was followed the next day by the beginning of the Astra 2D campaign.

Fueling of Astra 2D commenced on November 29, while filling of GE-8's fuel tanks began on December 2. The fueling process takes several days to complete.

The nearly complete Ariane 508 was transferred from its launcher integration building to the final assembly building on December 4, where it waited to be joined by its three payloads.

All three payloads were placed into position in and around the Sylda-5 multiple payload deployment system on December 6. During the ride to orbit, Astra 2D will be positioned on top of the "stack," with GE-8 below inside of the Sylda-5. LDREX will be positioned on the bottom of the "stack." The payload fairing that acts as a protective shield around the spacecraft was added to the mix on December 8, completing the assembly of the launch vehicle.

The storable propellant upper stage's attitude control system was fueled with its storable propellant on December 12. The storable propellant stage itself was fueled with its storable propellant combination, which includes monomethyl hydrazine as a fuel and nitrogen tetroxide as an oxidizer, on December 13.

A final launch rehearsal was performed on Thursday, December 14, followed the next day by the launch readiness review.

The Ariane 508 rocket will roll out from the final assembly building to the ELA-3 launch pad on Monday. Because of the design of both the rocket and launch pad, the vehicle is not required to be at the pad until just 24 hours before launch.

During the countdown on Tuesday, the cryogenic first stage will be filled with its propellant combination that consists of liquid oxygen and liquid hydrogen.

Stay with Spaceflight Now throughout the remainder of the launch campaign for continued updates.