Skynet (satellites)

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Launch of the first Skynet satellite, Skynet 1A, by Delta rocket in 1969 from Cape Canaveral

Skynet is a family of military satellites, now operated by Paradigm Secure Communications on behalf of the UK Ministry of Defence, which provide strategic communication services to the three branches of the UK Armed Forces and to NATO forces engaged on coalition tasks.

1 Models
2 External links

[edit] Models

[edit] Skynet 1

[edit] Skynet 2

Following the failure of one of the Skynet 1 satellites, the timetable for the launch of the Skynet 2 system was delayed. When Skynet 2A was launched on January 19, 1974, the second stage of the Delta rocket failed, placing the satellite in an unusable orbit. It was destroyed when it re-entered the earth's atmosphere on January 27.

Skynet 2B was successfully launched on November 23, 1974.

[edit] Skynet 3

Skynet 3 was abandoned in favour of the more advanced Skynet 4.

[edit] Skynet 4

Skynet 4 satellites have few similarities to the earlier generations. The cylindrical body of Skynet 1 and 2 was replaced by a large square body housing antennas with deployable solar-cell arrays. This marks the technological improvement from spin-stabilisation, used in earlier cylindrical satellites, to three-axis stabilisation using momentum wheels & reaction wheels controlling the satellite gyroscopically.

Skynet 4 were the first purely British built satellites, manufacture of 4A, 4B and 4C being carried out by British Aerospace Dynamics (BAe Dynamics). NATO adapted the design for the NATO IVA and IVB communication satellites, also manufactured by BAe Dynamics.

The improved Stage 2 satellites (4D, 4E and 4F) were built by Matra Marconi Space and Astrium to replace the earlier versions. Improvements included increased power and resistance to electronic jamming.

Skynet 4 provides SHF and UHF services using earth cover, wide area and spot beam coverage.

[edit] Skynet 5

Skynet 5 is the next generation of satellites, replacing the existing Skynet 4 Stage 2 system. It has been contracted via PFI to a partnership between Paradigm Secure Communications and EADS Astrium, a European spacecraft manufacturer. EADS Astrium will be responsible for the build & delivery of Skynet 5 satellites in orbit, whilst Paradigm will be responsible for provision of service to the MoD. Paradigm have also been contracted to provide communications services to NATO. The first of a constellation of three Skynet 5 vehicles is expected to launch in 2006, becoming operational in 2007 following In Orbit Test

The programme marks a change of approach in the UK from traditional defence procurement methods to a services-based contract which also includes provision of leased ground terminals, Reacher vehicles and Satellite Communications Onboard Terminal SCOT ship fits and the associated baseband equipment.

**Summary**
Model	Manufacturer	Launch date	Launch vehicle	Comments
Skynet 1
1A	Philco Ford	November 22, 1969	Delta M
1B	Philco Ford	August 19, 1970	Delta M	Apogee motor failure
Skynet 2
2A	Marconi Space Systems¹	January 19, 1974	Delta 2000	Rocket guidance failure
2B	Marconi Space Systems	November 23, 1974	Delta 2000
Skynet 4
4A	British Aerospace	January 1, 1990	Titan 34D
4B	British Aerospace	December 11, 1988	Ariane 44LP²
4C	British Aerospace	August 30, 1990	Ariane 44LP
Skynet 4 Stage 2
4D	Matra Marconi Space³	January 10, 1998	Delta 7000	Replaced 4B
4E	Matra Marconi Space	February 26, 1998	Ariane 44L
4F	Astrium⁴	February 7, 2001	Ariane 44L
Skynet 5
5A	EADS Astrium⁵	2006	Ariane 5
5B	EADS Astrium	2007	Ariane 5
5C	EADS Astrium	2007	Ariane 5

Notes

With technical assistance from Philco Ford
Launched with Astra 1A, the first of the European Astra satellite constellation
Marconi Space Systems merged to form Matra Marconi Space in 1990. MMS acquired BAe Space Systems in 1994.
In 2000 MMS merged with DASA's space division to form Astrium.
BAE Systems sold its 25% share of Astrium, renamed EADS Astrium