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by Simon Mansfield Jindabyne, Australia (SPX) Mar 19, 2012
A modern, state of the art communications satellite stranded last August in a useless orbit will constitute a double failure if Russian officials de-orbit the spacecraft as planned, according to an expert from the team hoping to salvage the spacecraft. The Russian Express-AM4 satellite, built by Astrium, was designed for geosynchronous orbit, but stranded in a six hour elliptical orbit at an inclination of 51 deg by a Proton Briz-M upper stage failure last August. Underwriters later declared the satellite a total loss and paid the insurance claim to the Russian Satellite Communications Co. (RSCC), owners of the spacecraft. Polar Broadband Ltd. (PBL) is working with satellite industry insurance experts and investors to salvage Express AM4, and both reposition and repurpose it in support of the international science community in the Antarctic. The company has proposed this salvage mission to a Russian working group that is tasked with deciding the fate of the spacecraft. William Readdy, a co-founder of PBL, told reporters last week at the Satellite 2012 conference, that the spacecraft could be easily placed into a new orbit which would provide Antarctic research bases with vastly superior communication links to those now available or envisioned in this decade. There is enough fuel for more than 10 years of orbit maintenance in addition to end of life disposal requirements. In addition, "The new Express AM4 orbit could provide 14 to 16 hours of daily coverage for the international scientific research bases in Antarctica," said Readdy. Readdy is a former Navy test pilot, and NASA astronaut. He commanded the Space Shuttle Atlantis STS-79, which docked with the Russian space station Mir in September of 1996. As associate administrator of NASA in 1998, Readdy helped arrange TRDSS relay satellite service for the National Science Foundation (NSF) U.S. Antarctic Program. This novel repurposing of the NASA relay satellite allowed transmission and reception of data from the Antarctic region and enabled the first telemedicine from the South Pole. TDRS F1 served the Antarctic for twelve years before its second retirement in 2010. Readdy identified the NSF as one of the primary customers for Express AM4 broadband services. An NSF Request for Information (RFI) for satellite broadband services reportedly received bids last summer in the range of $100 to $500 million, while the PBL plan for Express-AM4 would cost approximately $20 million, said Readdy. Recent reports from Satellite 2012 indicated that while the spacecraft was undamaged by the launch failure, extensive radiation exposure had drastically reduced the lifetime of the spacecraft, necessitating an immediate re-entry. A targeted re-entry was predicted between March 20 and March 26. Reports from last September indicated that the spacecraft also posed a threat to space navigation satellites. Michel Loucks, PBL co-founder and mission operations specialist, refuted these claims in a recent interview. "The reports I've heard about radiation damage and debris concerns for AM4 are incorrect," said Loucks. Loucks has 24 years of trajectory and flight operations experience, most recently worked operations on the NASA IBEX mission in 2008, as well as several recent commercial orbit-raising missions. Loucks' consulting firm, Space Exploration Engineering of Friday Harbor, WA, maintains a business partner relationship with Analytical Graphics Inc (AGI), creators of the STK suite of space mission analysis software. Loucks has written and taught classes both in the U.S. and internationally on the use of the STK for space mission analysis and design. He is currently serving as a trajectory consultant for the NASA/LADEE Lunar orbiter mission, scheduled to fly in 2013. "Our high-fidelity analysis of this orbit indicates that AM4 has received about 1/3 of the planned dosage for the designed 15 year lifetime of the spacecraft in GEO," said Loucks. "Our planned mission orbit has less than one third of the radiation exposure expected for a normal GEO spacecraft. So we could fly for 20 years and still be well under the stated lifetime exposure limits." The spacecraft is still well within its design limits for radiation, and these reports of damage are completely contradicted by our analysis and by that of several of our associates." Loucks said. Loucks continued: "The Astrium satellite is actually very well built and adaptable. The satellite can be easily configured to provide much needed broadband connectivity for the international science communities on the Antarctic and surrounding waters. Imagine live reporting from the lake Vostok drilling site. There are a lot of possibilities once you put this kind of capability in place." Loucks further described PBL plans to raise the orbit "responsibly", in a way that would mitigate the dangers of collisions with other spacecraft and orbiting debris. A flexible orbit-raising plan is in place that will incorporate the expertise and experience of several business partners, and would use the USSTRATCOM Joint Space Operations Center (JSpOC) through the JSpOC Commercial Satellite Owner/Operator program. "We have all the relationships and experience in place to do this right. Each maneuver can be re-planned at any time to avoid close encounters with other objects. Loucks said their plan was simple in comparison to the recent recovery of the Advanced Extremely High Frequency-1 spacecraft (AEFH-1). AEFH-1 was placed in a bad orbit in August of 2010. Using attitude control thrusters alone, controllers coordinated their burn plan with the JSpOC, and executed hundreds of burns over 14 months before reaching their final GEO orbit in October, 2011. The PBL burn plan calls for less than 20 burns, executed over a 2 month period. Dennis Wingo, a satellite industry veteran and co-founder of PBL says "we have an opportunity to take a written-off asset and use it to serve the Antarctic scientific community. This is the final frontier for communications. We intend to use this satellite to support the health and welfare of the scientists in the Antarctic as well as to enable science not currently possible without it. We hope that the Russian state commission will look favorably on our proposal". Background video that displays the orbit raising and maintenance concept.
- Space Technology News - Applications and Research
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