AEHF 1 has arrived in geosynchronous orbit

From: Ted Molczan (
Date: Wed Oct 26 2011 - 14:06:03 UTC

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    Mike McCants reports that AEHF 1 (10039A / 36868) reached synchronous orbit on 2011 Oct 25, near longitude 68 W, one of
    the operational Milstar/AEHF locations. Based on observations overnight, he provided the following elset, with the
    caution that eccentricity and argument of perigee remain uncertain:
    1 36868U 10039A   11298.86959040 0.00000000  00000-0  00000-0 0    09
    2 36868   4.4100 278.5854 0002000 241.0264 118.9823  1.00270000    04
    No doubt this is a time of celebration for the team of USAF, Aerospace Corporation and Lockheed Martin personnel who
    have worked for the past 14 months to overcome the loss of the spacecraft's liquid apogee engine, initially by using its
    hydrazine attitude control thrusters, followed by thousands of hours of hall current thruster firings over 12 months.
    Additional information is available in this recent progress report by Spaceflight Now:
    Manoeuvring AEHF 1 to its correct orbit, with sufficient propellant remaining to complete its planned mission, adds a
    new chapter to the long and distinguished history of overcoming serious in-orbit problems in civil, military and
    commercial spaceflight. I hope that some of technical reports on the rescue operations will appear in journals
    accessible to the public.
    A small team of hobbyists led by Mike McCants managed to keep track of AHEF 1 during its long climb to GEO, resulting in
    an accurate orbital history in TLE format. Here are the final plots of the evolution of the altitude, orbital period and
    inclination, from launch to arrival in geosynchronous orbit:
    The tracking was most challenging during the year-long HCT phase, during which the thrusters were fired nearly every day
    for between 12 and 24 hours. As the orbit evolved, Mike analyzed the trend in the elements and issued search TLEs
    projected several days ahead. This enabled Mike and colleagues Derek Breit, Scott Campbell, Kevin Fetter, Tim Luton,
    Greg Roberts, Peter Wakelin and Brad Young to observe the spacecraft during a total of 105 sessions from 2010 Oct 17
    through 2011 Oct 26. Very nice work by all involved!
    Ted Molczan
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