|  | Flight 157 on the launch pad | |
Flight 157 postponed a few days
29 November 2002
Arianespace issued the following press release this afternoon regarding the delay in the launch of the Ariane 5 10-tonne launcher.
The launch of flight 157 has been postponed by a few days following an
anomaly that occurred during the final phase of the launch preparation
sequence.
At 6.8 seconds before the transmission by the on-board system control to
ignite the Vulcain 2 engine, the ground operations control system
simultaneously gave the order to open the cryogenic arms and initiate
the external igniters (AMF) of the launch table, whose function is to
ignite the hydrogen which pre-chills the engine.
The igniter activation status report failed to reach the ground
operation control software and as a result the onboard control system
did not trigger the ignition sequence as scheduled at -3.0 seconds. Operations then ceased and the launch vehicle, HOTBIRD 7 and STENTOR, and
the launch system went into safe mode.
Draining of the cryogenic upper stage via the launch vehicle purge lines
is currently in process. The operations will continue until Saturday
morning, when the launch vehicle will be transferred back to the
Assembly building. At that point it will be possible to ascertain why the AMF ignition was
not acknowledged by the ground operations control system.
Rectifying the anomaly and reconfiguring the flight are not expected to
take more than a few days.
A new launch date will be announced early next week.
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