Satgen303 Stepson of Uosat ? by GM4IHJ 14th Jan 95 BID of this msg is SGEN303 Please use this BID if you retransmit this msg Amongst all the discussions about forthcoming satellite telephone systems such as Motorolas Iridium and Microsofts satellite armada, a new contender has suddenly emerged. Unlike the rest , it is not a voice telephone system. It is a message and data system which the organiser claims will start launching satellites next month in February 95. For several years now, Pegasus a system using winged launch vehicles released from high flying aircraft, has been undergoing tests. The parent company is Orbital Science Corporation, and their most recent launch was in June 94 when their Lockheed 1011 aircraft launched STEP 1, a Pegasus test flight which unfortunately blew up about 3 minutes after launch, and did not reach orbit. Since then Orbital have taken over Magellan Systems, who produce handsets , and have set up a joint operation with them to launch 26 satellites begining Feb 95. Launch will be by Pegasus to low earth orbit, with the satellite network planned to provide a message service worldwide, without using terrestrial or cellular telephones, at a message cost of less than 20p ( about 35 cents US ). Messages will be up to 250 characters long, and will be uploaded from simple handsets costing about $1000 each. Brief sketches of the satellites suggest they will carry microwave quadrifiliar antennas, but nowhere in the literature released so far does it say whether messages will be stored in individual satellites for later downloading to addressees ( as Uosat does with its store and forward system ), or, passed from satellite to satellite for immediate delivery as proposed for the Motorola Iridium system. The whole project appears to be commercially quite novel. Particularly in respect of Orbitals own launch vehicles which do not require special launch pads. But it remains to be seen how closely it follows Uosats tried and tested store and forward technique. Orbital make great play in their literature that though their system is less sophisticated than say Iridium, "It will be first ". No mention what so ever is made of the fact that Uosats have been doing just this for years , with Polar expeditions, Amateur E mail etc. Even the Gateway concept plans for some Orbital installations look like simple clones of the well tried Amsat Uosat Gateways. The network will be called Orbcomm. Hopefully they will get by without any more Pegasus explosions . In any event their efforts over the next few months should be interesting. Meanwhile other ventures coming along should see Iridium testing their concept with one or two satellites soon, before they go on to the full series of 66 satellites plannned to be operational in 1998 in 800km altitude orbits. One year later in 1999 Odyssey plan to have their 12 satellites in much higher 10000 km altitude orbits which should be interesting from the point of view of how they survive in the denser part of the radiation belts. While Globastar ( made by Loral, formerly Ford Aerospace), have not yet announced their launch plans, nor has the last group, which includes Bill Gates owner of Microsoft, who plan to put up several hundred satellites. Where will they all go, or, more likely how many of these ventures will merge or drop out because of the problems with raising the necessary finance? One thing is sure, the low earth orbit scene will never be the same what ever happens. 73 de John GM4IHJ @ GB7SAN