Satellite launch has success out at sea

Satellite launch has success out at seaSteve Bush
Sea Launch, which seemed the most unlikely of the up-and-coming satellite launch vehicles, has successfully completed its maiden flight.
The concept, taking a second-hand oil rig and firing Russian/Ukrainian-made rockets from it, was met with some scepticism when it was announced. Now early doubters will be wishing they had booked a ride on it.
There is a big shortage of reliable launch capacity for satellites. Launcher confidence has been made worse by the destruction of the first Ariane 5, a prototype Zenit (not the Sea Launch version) carrying 12 communication satellites and several Chinese Long March rockets.
Due to nervousness on the part of satellite companies, there was no satellite on-board the first Sea Launch. Instead it carried an instrumented dummy load similar to a Hughes 702 satellite chassis.
This was successfully delivered into a geostationary orbit.
The first launch, of a real Hughes 702, is due in August and the next 15 launch slots are all booked.
Sea Launch gets over the problem of non-optimal launch sites.
The equator is the best (cheapest) place to launch geostationary satellites from, because the rocket gains maximum energy from the Earth’s rotation, reducing fuel requirements.
But the take-off site has to have a lot of empty sea or land down-range – just in case the launch goes wrong and the rocket falls out of the sky. This limits the choice of sites.
The European Space Agency’s site in South America comes closest to the ideal, and can also launch to polar orbits, but Sea Launch can be moved to a nominally perfect position.
Sea Launch is actually two vessels, a rocket and a home port.
The vessels are the Sea Launch Commander (also called the Assembly and Command Ship, or ACS), a floating mission control centre and rocket assembly factory, and Odyssey, the converted oil-rig.
Home port is at Long Beach California and the rockets are three-stage type Z-3SL Zenits, modified for extra strength, reliability and guidance performance.
These rockets have the advantage that they burn kerosene and liquid oxygen, a low-tech fuel that makes them less of an environmental problem than launchers like Ariane 5, which produce tonnes of corrosive chemicals when fired. Z-3-SLs can also be transported horizontally, unlike most US-made rockets.
Although, for the first launches, rockets will be transferred to Odyssey at the home port. The intention is eventually to leave Odyssey out in the ocean and ferry Zenits, up to three at a time, out to it in the ACS.
The ACS, was built at the Govan Shipyard in Glasgow and is 200m long displacing 34,000 tonnes and has a range of 18,000 nautical miles. Odyssey is claimed to be the largest semi-submersible self-propelled vehicle in the world and is 134m by 67m, displacing 50,000 tonnes when most deeply submerged. The rocket is 60m tall and 4.3m wide at the base.
Sea Launch is 40 per cent owned by Boeing, included when it bought McDonnell Douglas recently. Other big shareholders are Kvaerner Maritime of Oslo, Norway (the vessel builder with 20 per cent); RSC-Energia of Moscow, Russia (provides the Block-DM upper stage and its integration with the launch vehicle with 25 per cent); and KB Yuzhnoye/PO Yuzhmash of Ukraine (provides the first two stages of the launch vehicle with 15 per cent). Process lays down electrical conductors on plastic
Scientists at the Fraunhofer Institute for Laser Technology in Aachen, Germany, have developed a process which allows them to apply electrical conductors to injection-moulded parts.
To lay-down tracks, selected parts of the plastic component are exposed to short-wavelength ultraviolet light from an excimer lamp or excimer laser altering the surface chemistry. After exposure, the plastic is dipped in an aqueous solution, where a metal compound binds to the exposed areas. After several different baths, over a few minutes, a complete copper or nickel layer forms.
The layer is under 1?m thick but can be built up to the standard 25?m using electroplating.
As thick layers do not adhere as well as thin layers, because of internal stresses in the metal, the Fraunhofer group has developed a pre-treatment roughening process for the plastic surface to improve adhesion.
This involves applying an excimer laser through a mask generating tiny depressions where the metal will later be deposited.
Fraunhofer is aiming the whole process at automotive and mobile phone sub-assemblies.


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