BY SPACEFLIGHT NOW

Follow the preparations and launch of the Indian Insat 3C satellite aboard an Arianespace Ariane 4 rocket. Reload this page for the very latest on the mission.

THURSDAY, JANUARY 24, 2002

A satellite designed to enhance communications across India and replace two aging craft was successfully launched into Earth orbit Wednesday by a European Ariane 4 rocket following a bumpy countdown that featured an abort just seconds before ignition. Read our full launch story.

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

Indian Space Research Organization officials at the launch report their newly launched Insat 3C satellite has been acquired by ground controllers. Initial examination of the spacecraft's status indicates all is well.

0012 GMT (7:12 p.m. EST Wed.)

Arianespace has confirmed success for today's launch of Insat 3C. This marks the 66th straight success for the Ariane 4 rocket dating back to 1995.

We'll have a full wrap-up story and pictures a bit later this evening.

0008 GMT (7:08 p.m. EST Wed.)

Plus+21 minutes. SPACECRAFT SEPARATION! The Insat 3C communications spacecraft has been released into space from the Ariane 4 rocket's third stage, completing today's launch of Arianespace Flight 147. A huge round of applause has erupted in the launch control center.

The satellite has been delivered into an elliptical geosynchronous transfer orbit. Its onboard kick engine will be fired over the coming days to achieve a circular geostationary orbit, ultimately arriving at 74 degrees East longitude above the equator where it will be parked to provide coverage over India.

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

Plus+19 minutes. The third stage shut down, completing the powered phase of today's launch. The stage will now provide the necessary pointing for deployment of the Insat 3C spacecraft over the next two minutes.

0004 GMT (7:04 p.m. EST Wed.)

Plus+17 minutes, 30 seconds. The Libreville tracking station in Africa has acquired the rocket's signal.

0003 GMT (7:03 p.m. EST Wed.)

Plus+16 minutes, 30 seconds. About two minutes remaining in the third stage burn.

0001 GMT (7:01 p.m. EST Wed.)

Plus+14 minutes. The rocket is now the period in flight where its climb levels out a bit in order to gain speed.

2359 GMT (6:59 p.m. EST)

Plus+12 minutes, 15 seconds. The third stage is still firing. Altitude is 507 km, velocity 6.24 km/sec.

2358 GMT (6:58 p.m. EST)

Plus+11 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.

2357 GMT (6:57 p.m. EST)

Plus+10 minutes, 30 seconds. All vehicle parameters still reported normal. Altitude is 460 km, velocity 5.71 km/sec.

2356 GMT (6:56 p.m. EST)

Plus+9 minutes. Altitude is 419 km, velocity 5.3 km/sec.

2355 GMT (6:55 p.m. EST)

Plus+8 minutes. Arianespace reports the rocket's systems are performing as expected and trajectory is normal.

2354 GMT (6:54 p.m. EST)

Plus+7 minutes. Third stage burn is continuing. Altitude 327 km, velocity 4.94 km/sec.

2353 GMT (6:53 p.m. EST)

Plus+6 minutes. The Natal tracking station in Brazil has picked up the rocket's signal as it travels downrange.

2352 GMT (6:52 p.m. EST)

Plus+5 minutes, 40 seconds. The second stage has burned out and separated. And the cryogenic upper stage has ignited for its lengthy burn to deliver the Insat 3C satellite payload into the desired geosynchronous transfer orbit.

2352 GMT (6:52 p.m. EST)

Plus+5 minutes, 30 seconds. No problems reported thus far in the flight of the Ariane 4 rocket. Standing by for staging. Altitude is 230 km, velocity 4.7 km/sec.

2351 GMT (6:51 p.m. EST)

Plus+4 minutes, 30 seconds. Altitude is 161 km, velocity 3.4 km/sec.

2350 GMT (6:50 p.m. EST)

Plus+3 minutes, 50 seconds. The payload fairing has been jettisoned since it is no longer needed to shield the Insat 3C spacecraft.

2350 GMT (6:50 p.m. EST)

Plus+3 minutes, 30 seconds. The four first stage main engines have shut down and stage separation confirmed. The second stage has now ignited.

2350 GMT (6:50 p.m. EST)

Plus+3 minutes. Altitude 73 km, velocity 2.15 km/sec.

2349 GMT (6:49 p.m. EST)

Plus+2 minutes, 30 seconds. The two liquid-propellant strap-on boosters have shut down and jettisoned from the base of the Ariane 4 rocket.

2348 GMT (6:48 p.m. EST)

Plus+1 minute, 45 seconds. Altitude 18 km, velocity 0.6 km/sec.

2347 GMT (6:47 p.m. EST)

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

2347 GMT (6:47 p.m. EST)

LIFTOFF! Liftoff of the Ariane 4 rocket with the Insat 3C satellite for the Indian Space Research Organization. And the vehicle has cleared the tower!

2346 GMT (6:46 p.m. EST)

Minus-1 minute and counting.

2345 GMT (6:45 p.m. EST)

Minus-2 minutes and counting. The third stage liquid oxygen tank has been pressurized for the launch. Also, the Insat 3C spacecraft is switching back to internal power.

2343 GMT (6:43 p.m. EST)

Minus-4 minutes. The new launch time will soon be loaded into the rocket's computer.

2341 GMT (6:41 p.m. EST)

Minus-6 minutes and counting! The synchronized launch sequence has been started for a second time. Looking for a liftoff at about 2347 GMT.

2341 GMT (6:41 p.m. EST)

The status panel in the Jupiter launch control center is just gone "green". So the computer trouble has been resolved. Countdown will be restarted shortly.

2333 GMT (6:33 p.m. EST)

The launch team has just been informed that the countdown could be resuming in a few minutes. So there is still hope for a launch in the next half-hour.

The rocket's third stage cryogenics -- liquid hydrogen and liquid oxygen -- are being topped off, readying the rocket for a possible second try at liftoff today.

2329 GMT (6:29 p.m. EST)

A half-hour is remaining in today's window to launch the Ariane 4 rocket with the Insat 3C spacecraft. The countdown has been recycled to T-minus 6 minutes and holding. Therefore, the clock has to resume by 2353 GMT in order to last at the very last moment of today's opportunity. Otherwise, liftoff will have to be scrubbed for the day.

2317 GMT (6:17 p.m. EST)

The launch team has determined the countdown cutoff was caused when one of the two master countdown computers detected a problem with the other computer. The two computers have different sets of systems on the launch pad and rocket for which they are responsible, but they check each other's work to ensure there are no mistakes, an Arianespace spokesman said. It was during the cross-check that the trouble was noted, forcing a hold in the countdown.

So the countdown remains holding at T-minus 6 minutes.

2308 GMT (6:08 p.m. EST)

Arianespace says one of the two countdown-control computers had an alarm, which caused the count to be stopped. One computer is responsible for fluids and propellants. The other controls the 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. It is not clear at this point which computer had the alarm.

2300 GMT (6:00 p.m. EST)

The launch team continues to study whatever the problem was that caused the computer-controlled countdown to be halted at the T-minus 11 second point. Arianespace has not provided any insight into the trouble other than to say it involves the launch pad.

The countdown is being reset to T-minus 6 minutes while the troubleshooting continues. If the issue can be cleared, the count could resume from T-minus 6 minutes for liftoff during today's available launch window that extends to 2359 GMT (6:59 p.m. EST).

2255 GMT (5:55 p.m. EST)

Today's available launch window extends until 2359 GMT (6:59 p.m. EST). So engineers are troubleshooting the situation and could try again within the next hour if the problem can be resolved. We will update as information becomes available.

2254 GMT (5:54 p.m. EST)

Initial report from Arianespace is the "red" condition that has held the countdown involves launch pad equipment. Countdown clocks are being recycled back to the Minus-6 minute mark.

2252 GMT (5:52 p.m. EST)

ABORT! Countdown clock has stopped at about Minus-11 seconds.

2252 GMT (5:52 p.m. EST)

Minus-1 minute. Equipment aboard the Ariane 42L 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.

2251 GMT (5:51 p.m. EST)

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

2249 GMT (5:49 p.m. EST)

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 Insat 3C spacecraft will be confirmed on internal power and declared ready for launch.

2247 GMT (5:47 p.m. EST)

Minus-6 minutes and counting. The synchronized launch sequence has started. Computers are now in control of this final portion of the launch countdown. Liftoff is set for 2253 GMT (5:53 p.m. EST).

During the next six minutes, the Ariane 42L 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 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.

2244 GMT (5:44 p.m. EST)

Minus-9 minutes and counting. Weather conditions at the Guiana Space Center have been verified acceptable for liftoff throughout tonight's available 66-minute launch window. The countdown continues smoothly for blastoff at 2253 GMT.

2241 GMT (5:41 p.m. EST)

Minus-12 minutes. The Ariane 42L rocket stands 56.3 meters tall and weighs 317 metric tons at liftoff. This particular version of the Ariane 4 features two strap-on liquid-fueled boosters. The Insat 3C spacecraft accounts for 2,750 kg (6,050 pounds) of the launch weight.

2233 GMT (5:33 p.m. EST)

Minus-20 minutes and counting down to today's launch of the Ariane 42L rocket with the Insat 3C communications satellite.

The three-stage rocket has been fully fueled and prepared for liftoff at 2253 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.

For the first time in memory, Arianespace is not providing a live television broadcast of the launch to the United States. Therefore, our updates will be somewhat limited compared to Ariane launches we have covered in the past.

WEDNESDAY, JANUARY 23, 2002

Arianespace is counting down the final hours for today's launch of an Ariane 42L rocket with an Indian communications satellite on-board.

Flight 147 is scheduled leave the planet bound for space at 2253 GMT (5:53 p.m. EST), at the beginning of a 66-minute launch window. Liftoff will occur from the ELA-2 launch pad at the Guiana Space Center in Kourou, French Guiana.

Enclosed inside the Ariane 42L's payload fairing is India's Insat 3C telecommunications satellite, which will provide television transmission and other communication links throughout the Indian subcontinent. The craft will be trucked into a geostationary transfer orbit by the Ariane 4, and then will use its own propulsion systems to place itself into a circular geostationary orbit 22,300 miles above a point at 74 degrees East, or over the Indian Ocean.

Built and to be operated by the Indian Space Research Organization, or ISRO, the 6,050-pound satellite features 30 C-band transponders, 2 S-band transponders, and a single mobile satellite service transponder for use in its communications mission during the craft's expected 12-year lifetime. Once fully deployed, the spacecraft's power-producing solar panels will stretch around 50 feet tip-to-tip.

Insat 3C was previously scheduled to fly into orbit aboard an Ariane 5 rocket last September, but a failure of an Ariane 5 during the summer grounded the fleet. That forced Arianespace to switch some payloads to the less-powerful Ariane 4 version, including the payloads of the September Ariane 5 launch -- Atlantic Bird 2 and Insat 3C. Atlantic Bird 2 was launched successfully in late September, and Wednesday's launch completes the pair.

Since the last update, the rocket was cleared for flight after the pre-launch readiness review that was held on Monday. Soon after, the Ariane 4's pyrotechnics were armed.

The launcher's first stage, second stage, and twin liquid-fueled boosters were fueled with their propellant load of unsymmetrical dimethyl hydrazine and nitrogen tetroxide on Tuesday.

Looking ahead to the events of the countdown and launch on Wednesday, the final countdown will commence at 1023 GMT (5:23 a.m. EST). At 1718 GMT (12:18 p.m. EST), the protective service gantry at ELA-2 will begin retracting away from the launch pad. Liquid hydrogen and liquid oxygen propellant will begin flowing into the Ariane 42L's third stage at 1918 GMT (2:18 p.m. EST). The launcher's telemetry, telecommand, and radar transponder systems will be switched on at 2148 GMT (4:48 p.m. EST). At 2247 GMT (5:47 p.m. EST), the countdown will enter the synchronized launch sequence. Following that milestone are a series of fast-paced events culminating in the ignition of the rocket's first stage and two liquid-fueled strap-on boosters. Liftoff will follow just 4 seconds later.

After launch, Flight 147 will take a normal Ariane 42L ascent profile with a 2-minute, 19-second burn of the liquid-fed boosters. The first stage will separate at a point a little after 3 minutes after launch, followed immediately by second stage ignition. The vehicle's payload fairing will be jettisoned 3 minutes, 39 seconds into flight, exposing the satellite payload to space for the first time. The second stage will burn out and the third stage will take over at around 5 minutes, 30 seconds after liftoff. The third stage will then burn for around 13 minutes before cutting off to prepare for spacecraft separation, which is scheduled for 20 minutes, 52 seconds into flight.

Flight 147 marks the 146th launch of an Ariane rocket, and the 108th flight of an Ariane 4. It is also the 13th time an Ariane 42L -- the version with two liquid-fueled boosters -- has been flown. After Wednesday's slated liftoff, just eight more Ariane 4's remain to be launched before the venerable launcher is retired in favor of the newer and more powerful Ariane 5 rocket.

Stay with Spaceflight Now for updates on the final countdown and launch of Arianespace Flight 147.

MONDAY, JANUARY 21, 2002

Arianespace plans to kick off its 2002 launch season on Wednesday evening with the flight of an Ariane 4 rocket carrying the Insat 3C satellite for the Indian space agency.

Liftoff is scheduled for 2253 GMT (5:53 p.m. EST) from the Guiana Space Center in Kourou, French Guiana. The launch window extends until 2359 GMT (6:59 p.m. EST).

The Ariane 42L will haul its satellite cargo into geostationary transfer orbit for the Indian Space Research Organization, or ISRO. Using its various types of transponders, the craft will provide telecommunications and television broadcast services to users across India.

The 6,050-pound spacecraft will later boost itself into geostationary orbit at the slot at 74 degrees East longitude, 22,300 miles high above the Indian Ocean and in full view and broadcast range of the Indian subcontinent.

Insat 3C was originally slated to fly aboard an Ariane 5 rocket in September 2001 along with the Atlantic Bird 2 satellite. However, that was changed after the July mishap when an Ariane 5 failed to place two satellites into their proper orbit, resulting in the grounding of the heavy-lift Ariane 5 rocket. Atlantic Bird 2 and Insat 3C were then shifted to launch individually aboard a pair of less-powerful Ariane 4 rockets. Atlantic Bird 2 was successfully launched in late September.

Once targeted for launch on January 16, officials decided to delay Insat 3C's liftoff for one week to allow ISRO to conduct additional checks on the spacecraft in Kourou.

Preparations for Arianespace Flight 147 began on December 3 with the placement of the launcher's first stage onto the mobile launch table and the arrival of Insat 3C.

The Ariane 42L's second stage was erected atop the vehicle's first stage on December 4. The two liquid-fueled strap-on boosters were put into place on the first stage on December 6 and 7, followed on December 10 by the attachment of the launcher's third stage.

The hazardous fueling operations for Insat 3C's propulsion and attitude control systems began on December 26.

The launcher was transported to the ELA-2 launch pad on January 9, clearing the way for final preparations to begin on January 11.

Insat 3C and its associated hardware were transferred to the pad last Tuesday, followed on Wednesday by the placement of the payload unit atop the Ariane 42L.

A pre-launch readiness review is scheduled for today, when a final "go" for launch will be determined. The launcher's pyrotechnic devices will then be made ready for flight.

On Tuesday, the launcher's first stage, second stage and two liquid-fueled boosters will be filled with their load of unsymmetrical dimethyl hydrazine and nitrogen tetroxide propellant.

Stay with Spaceflight Now for continued updates on the preparations for Flight 147 and live play-by-play reports during the final countdown and launch.