These small satellites are "transparent” to the primary payload and are deployed from the ASAP after the primary payload has departed. The Ariane H10 upper stage can be re-oriented into a 3-axis mode or spun up to about 3 rpms. depending on the satellite's needs. No power or telemetry is possible, other than the command to fire the satellites' pyrotechnic devices and a telemetry indication that the satellites have separated from ASAP. These small satellites must be built essentially to the same safety standards as any other pay load on Ariane 4. Normally. ASAPs are used for LEO sun-synchronous missions because the majority of the small satellite payloads are for store-and-forward communications activities. Such launch opportunities occur every 2 to 3 years. However, it is also possible to use ASAP for launches into GTO provided only a single primary pay load is being launched (i.e. without SPELDA). The first GTO launch will occur in 1992 with the launch of two STRV small satellites being built by the UK Royal Aircraft Establishment [5]. According to Arianespace. the total cost for a dedicated ASAP is less than 1 MAU. Equally importantly, there are between 3-4 launch opportunities into GTO every year throughout the mid-1990s because of the increasing demand for dedicated Ariane flights. For LEO launches, opportunities are far more scarce because, on average, one launch into sun-synchronous orbit is planned every year or so and this is the prime orbit demanded by small communications satellite builders. Currently, the only available options are anticipated as being in 1995/96 with the launch of ERS-2 and in 1997 with the launch of SPOT-4.[6] ASAP is the lowest cost/most available launch opportunity currently available. However, opportunities to use it will end in 1997/98 with the introduction of Ariane 5. Arianespace hopes to continue an ASAP-type service with Ariane 5. although no plans have yet been established to implement one.
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