The W1 communications satellite developed for Eutelsat no longer being available, the W2 satellite, which was to have been carried as a commercial passenger on Ariane 503, will be launched by an Ariane-4 vehicle.
The search for a new passenger cannot be reconciled with the planning schedule leading to entry of Ariane-5 into operational service. The Ariane 503 payload will therefore consist, in addition to the ARD (Atmospheric Reentry Demonstrator) - which has already been delivered to the Guiana Space Centre - of a representative mock-up of the W2 satellite. With these two payloads, the Ariane 503 flight will complete the qualification of the Ariane-5 launcher.
Taking account of the time needed to develop, test and integrate the mock-up, the Ariane 503 launch is now scheduled for mid-October 1998. Ariane-5 is an ESA programme for which ESA has delegated management responsibility to CNES.
Flight 503, conducted under ESA responsibility, will be the last of the Ariane-5 qualification flights. The launcher used will be the first production-series unit ordered by Arianespace from European industry.
Launch operations are managed by Arianespace at the ELA-3 launch site at the Guiana Space Centre, Europe's space port (French Guyana).