Value chain · CLM-1460
Low confidence
The evidence behind this statement is thin, indirect or second-hand. Read it as a lead to check, not as a settled finding.
In plain terms
When a US military satellite's main engine for climbing to its high orbit failed in 2010, press reports from 2010 and 2012 say its small chemical thrusters and then its electric thrusters lifted it the rest of the way; on their dates the electric thrusters were in use for about a year, two months longer than the recovery plan expected, and the satellite reached its final orbit about 14 months after launch.
The claim as recorded
Air Force Magazine reported in January 2012 (SRC-414) that AEHF-1, a US military communications satellite of 13,420 lb (about 6,087 kg) launched on 14 August 2010, could not use its liquid apogee engine after two failed firings that August; that its hydrazine reaction engine assembly thrusters then raised the perigee to more than 2,900 miles by 22 September 2010; and that its Hall Current Thrusters did the rest of the climb, in Phase 3 from October 2010 to 2 June 2011 (eight months, perigee from about 3,000 to more than 17,000 miles) and again in Phase 4, until the orbit was circular at geosynchronous altitude on 24 October 2011, 14 months from launch - so the Hall-thruster phase ran about 12 months in all (our arithmetic from those dates). Spaceflight Now reported on 2010-10-17 (SRC-415) that the pre-launch plan had already given the Hall Current Thrusters the last part of the climb, to geosynchronous orbit by December 2010, and that the recovery then expected about 10 months of Hall-thruster firing.
Scope and limits
An off-nominal recovery, not a by-design electric transfer: the satellite started from the orbit its hydrazine thrusters reached, not the intermediate orbit its apogee engine was meant to reach, so the duration must not be read as comparable to the by-design all-electric transfer durations in CLM-0702. Both sources are press reports, and the phases and dates are as they report them from the programme's own account. The mass is the figure SRC-414 prints for the satellite as it went into its first orbit. Neither source names the thruster model or the number of thrusters, so neither may be attributed to this record; SRC-415 gives the maker and a 4.5 kW rating. The 12 months is our arithmetic from SRC-414's dates; SRC-414 itself gives Phase 3 as eight months and the whole rescue as 14 months.
What it assumes
No assumptions are recorded against this claim.
Where it comes from
: "The 13,420-pound SV-1 went into a highly elliptical orbit"; "On Sept. 22, 2010, the spacecraft reached a perigee of more than 2,900 miles"; Phase 3 "began in October 2010 and did not end until June 2, 2011"; "From late October 2010 to June 2011, the HCTs burned for 10 to 12 hours per day"; in Phase 4, "The HCTs again were firing for long periods every day"; "The declining apogee reached proper altitude Oct. 24. The circle was formed". SRC-415: "The electric propulsion system using Hall Current Thrusters then would finish shaping the orbit into a circular, geosynchronous altitude 22,300 miles high and inclined 4.8 degrees by December"; the satellite was warming up its thrusters "to begin 10 months of propulsion-with-persistence"; "The HCTs, produced by Aerojet, are 4.5-kilowatt units".
Basis: months
Related records
- Answers question
- QST-002 not published in this release
- Supersedes
- CLM-0678 not published in this release
Cite this
energyaperture.com/c/clm-1460
CLM-1460, Energy Aperture, as of 2010-2011.