Ariane 5 - Notable Launches

Notable Launches

Ariane 5's first test flight (Ariane 5 Flight 501) on 4 June 1996 failed, with the rocket self-destructing 37 seconds after launch because of a malfunction in the control software. A data conversion from 64-bit floating point value to 16-bit signed integer value to be stored in a variable representing horizontal bias caused a processor trap (operand error) because the floating point value was too large to be represented by a 16-bit signed integer. The software was originally written for the Ariane 4 where efficiency considerations (the computer running the software had an 80% maximum workload requirement) led to 4 variables being protected with a handler while 3 others, including the horizontal bias variable, were left unprotected because it was thought that they were "physically limited or that there was a large margin of error". The software, written in Ada, was included in the Ariane 5 through the reuse of an entire Ariane 4 subsystem despite the fact that the particular software containing the bug, which was just a part of the subsystem, was not required by the Ariane 5 because it has a different preparation sequence than the Ariane 4.

The second test flight (L502, on 30 October 1997) was a partial failure. The Vulcain nozzle caused a roll problem, leading to premature shutdown of the core stage. The upper stage operated successfully but could not reach the intended orbit.

A subsequent test flight (L503, on 21 October 1998) proved successful and the first commercial launch (L504) occurred on 10 December 1999 with the launch of the XMM-Newton X-ray observatory satellite.

Another partial failure occurred on 12 July 2001, with the delivery of two satellites into an incorrect orbit, at only half the height of the intended GTO. The ESA Artemis telecommunications satellite was able to reach its intended orbit on 31 January 2003, through the use of its experimental ion propulsion system.

The next launch did not occur until 1 March 2002, when the Envisat environmental satellite successfully reached an orbit 800 km above the Earth in the 11th launch. At 8111 kg, it was the heaviest single payload until the launch of the first ATV on March 9, 2008 (~9000 kg).

The first launch of the ECA variant on 11 December 2002 ended in failure when a main booster problem caused the rocket to veer off-course, forcing its self-destruction three minutes into the flight. Its payload of two communications satellites (Stentor and Hot Bird 7), valued at about EUR 630 million, was lost in the ocean. The fault was determined to have been caused by a leak in coolant pipes allowing the nozzle to overheat. After this failure, Arianespace SA delayed the expected January 2003 launch for the Rosetta mission to 26 February 2004, but this was again delayed to early March 2004 due to a minor fault in the foam that protects the cryogenic tanks on the Ariane 5. As of November 2012, the failure of the first ECA launch was the last failure of an Ariane 5; since then, all subsequent launches have been successful, with 52 consecutive successes that stretch back to 9 April 2003 with the launch of INSAT-3A and Galaxy 12 satellites.

On 27 September 2003 the last Ariane 5 G boosted three satellites (including the first European lunar probe, SMART-1), in Flight 162. On 18 July 2004 an Ariane 5 G+ boosted what was at the time the heaviest telecommunication satellite ever, Anik F2, weighing almost 6,000 kg.

The first successful launch of the Ariane 5 ECA took place on 12 February 2005. The payload consisted of the XTAR-EUR military communications satellite, a 'SLOSHSAT' small scientific satellite and a MaqSat B2 payload simulator. The launch had been originally scheduled for October 2004, but additional testing and the military requiring a launch at that time (of an Helios 2A observation satellite) delayed the attempt.

On 11 August 2005, the first Ariane 5GS (featuring the Ariane 5 ECA's improved solid motors) boosted Thaïcom-4/iPStar-1, the heaviest telecommunications satellite to date at 6,505 kg, into orbit.

On 16 November 2005, the third Ariane 5 ECA launch (the second successful ECA launch) took place. It carried a dual payload consisting of Spaceway-F2 for DirecTV and Telkom-2 for PT Telekomunikasi of Indonesia. This was the rocket's heaviest dual payload to date, at more than 8,000 kg.

On 27 May 2006, an Ariane 5 ECA rocket set a new commercial payload lifting record of 8.2 tonnes. The dual-payload consisted of the Thaicom 5 and Satmex 6 satellites.

On 4 May 2007 the Ariane 5 ECA set another new commercial record, lifting into transfer orbit the Astra 1L and Galaxy 17 communication satellites with a combined weight of 8.6 tonnes, and a total payload weight of 9.4 tonnes. This record was again broken by another Ariane 5 ECA, launching the Skynet 5B and Star One C1 satellites, on 11 November 2007. The total payload weight for this launch was 9,535 kg.

On 9 March 2008, the first Ariane 5 ES-ATV was launched to deliver the first ATV called Jules Verne to the International Space Station. The ATV was the heaviest payload ever launched by a European rocket, providing supplies to the space station with necessary propellant, water, air and dry cargo. This was the first operational Ariane mission which involved an engine restart in the upper stage. (The ES-ATV Aestus EPS upper stage was restartable while the ECA HM7-B engine was not.)

On 1 July 2009, an Ariane 5 ECA launched TerreStar-1, the largest commercial telecommunication satellite ever built.

On 28 October 2010, an Ariane 5 ECA launched Eutelsat's W3B (part of its W Series of satellites) and Broadcasting Satellite System Corporation (B-SAT)'s BSAT-3b satellites into orbit. However, the W3B satellite failed to operate shortly after the successful launch and was written off as a total loss due to an oxidizer leak in the satellite's main propulsion system. The BSAT-3b satellite, however, is operating normally.

On 22 April 2011, the Ariane 5 ECA flight VA-201 broke a commercial record, lifting Yahsat 1A and Intelsat New Dawn with a total payload weight of 10,064 kg to transfer orbit. This record was later broken again during the launch of Ariane 5 ECA flight VA-208, lifting a total of 10182 kg into the planned geosynchronous transfer orbit.

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