Transfer of Ariane 503, V112 to the launch pad, on the Launch Zone 3 (ZL3) on the 20 October 1998.

The launch took place the 21 of October 1998.

Ariane-5 is an ESA programme for which ESA 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 Guiana).