SLIDE 17 Sub-document Bundles From Notes Grouped by Theme
Raymond Orye, head of the Ariane-5 program, said the exhaust nozzles at the base of two booster rockets swiveled abnormally and broke off, triggering an on-board self-destruction mechanism. About 500 channels of good telemetry were acquired until the breakup, which along with movie and video footage should provide an accident investigation board with sufficient data. ESA and CNES officials were forming the board late last week, and want an independent report by mid-July detailing the cause of the accident and proposed modifications. Attempts will be made to recover the on-board computers and other key parts. The terrain is a mixture of savannah and muddy mangrove trees. The rocket veered off course 37 seconds into flight and was destroyed, raining flaming debris near the European Space Agency's launch center off French Guiana. Journalists at the control centre heard two explosions and saw a giant wreath of orange flames and blazing wreckage about five kilometres away. Officials then hustled them indoors and evacuated the area. The Ariane 5 launcher failed on its first flight last week after gimbals on all three rocket engines moved to full deflection. The gimballing caused the 1.6-million-lb. launcher to pitch and yaw at rates estimated at 30 deg./sec. It quickly broke up from the airloads, and the breakup triggered an auto-destruct system that reduced Ariane 5 to a broad shower of flaming debris. Though spectacular, the debris caused no known injuries or property damage. KOUROU, FRENCH GUIANA, 1996 JUN 4 (NB)
- - The maiden launch of Europe's Ariane-5 rocket
went badly wrong this morning in Kourou, French Guiana when the rocket exploded just seconds into
- flight. The rocket was seen to climb strongly for
several seconds before nose diving towards the ground and exploding.Members of the ground crew, journalists, guests, and those down range from the launch site were immediately evacuated because of the danger of falling debris, much of which was white hot, and an almost full tank of flaming fuel. THE INDEPENDENT INVESTIGATION BOARD APPOINTED AFTER THE FAILED ARIANE 501 LAUNCH ON JUNE 4 SUBMITTED ITS REPORT ON JULY 16. ANALYSIS OF THE TELEMETRY AND AN EXAMINATION OF ONE OF THE INERTIAL REFERENCE SYSTEMS (IRS) RECOVERED REVEALED THE CAUSE OF THE FAILURE AND HOW IT ORIGINATED: A MALFUNCTION OF THE IRS SOFTWARE FOLLOWING NUMERICAL OVERFLOW IN AN UNPROTECTED DATA VARIABLE DUE TO A DESIGN FLAW. THE VARIOUS ENGINEERING TEAMS HAVE LOST NO TIME IN DEALING WITH THE PROBLEM, AND QUALIFICATION FLIGHT 502 IS NOW EXPECTED IN THE FIRST HALF OF 1997.
Description of the failure
The Ariane 5, developed over 10 years at a cost of $ 7 billion, was to be the successor to the Ariane 4.
Background
Ariane5's disastrous maiden launch, which ended when the rocket and its Pounds 500 million cargo had to be blown up a minute into their flight. The Ariane 5 rocket took off from a South American jungle base at 8:35 a.m. EDT loaded with four solar science satellites valued at $ 500 million. Qualification flight V501 on June 4 was conducted by the European and French space agencies (ESA and CNES) and carried four Cluster magnetospheric research satellites worth $500 million that were to be placed in a 22,350 X 175-
- mi. geosynchronous transfer orbit (see p. 22).
Aerospatiale is the ``industrial architect'' for Ariane 5 and is responsible for the main cryogenic stage and solid rocket boosters (AW&ST May 6, p. 60).
Payload
The next flight, Ariane V502, was set for October- November but may be delayed to early 1997, depending on the report. One of its two payloads is to be the Atmospheric Reentry Demonstrator, and officials are offering discounts to fill the other slot with a commercial satellite. Flight V502 was to be the second and final qualification flight, and ``we have no reason yet to consider an additional qualification flight,'' said Michel Mugnier, head of the CNES launcher
- division. ``Financial issues could arise in the last
quarter of 1996 if there was a requirement to implement major and costly modifications.'' If it turns out to be the software that sent the rocket to oblivion, that would suit everybody. 'That's the easiest thing to put right,'
Impact on 502
The Ariane explosion should not be allowed to
- bscure the ESA's proud record. Commercially,
Europe is the world's leader in the launching of
- satellites. The Ariane disaster, although it involved a
scientific rather than a commercial launch, may dent the ESA's reputation for reliability and threaten future contracts, but it should be borne in mind that rocket launches are inherently risky. Evidence to date suggests that the agency is the most rigorous of
record should help it to survive this setback. The Ariane 5 rocket failure caused reverberations in the international insurance market yesterday, even though it was not insured and the loss will be borne by the European Space Agency. After Tuesday's disaster underwriters are likely to take a more careful approach to commercial launches anywhere and insurance premiums may rise. The European programme has a relatively good reputation among satellite underwriters. 'If they have got it wrong, we're going to be that much more cautious,' said Mr Simon Clapham, underwriter at Marham Space Consortium at Lloyd's of London. On the other hand, the Ariane 5 failure might persuade backers of future launches to take out more insurance. The immediate impact will be to delay qualification
- f Ariane 5, but industry officials expect the long-
term effect on Arianespace will be small (see p. 21). The failure is the worst accident in European space history, coming at the culmination of an 8-10-year, $8-billion development program. Ariane 5 was designed to be man-rated with higher reliability than Ariane 4, but the new redundant computers appear to have allowed, if not caused, a fatal mistake.
- - not least because no astronauts were involved. A
further 14 rockets are in the Arianespace production line, so providing the fault is not generic, the program will not suffer too much.
Impacts - economic, insurance, reputation
