Attachment STA Narrative SAT-STA-20150317-00011

Attachment STA Narrative

This document pretains to SAT-STA-20150317-00011 for Special Temporal Authority on a Satellite Space Stations filing.

IBFS_SATSTA2015031700011_1080488

Before the
FEDERAL COMMUNICATIONS COMMISSION
Washington, D.C. 20554

In the Matter of Request of )
)
XM RADIO LLC ) Call Sign S2118
)
For Special Temporary Authority to )
Extend the XM-1 License Term and )
Revise the Orbital Debris Mitigation Plan )

REQUEST FOR EXTENSION AND MODIFICATION OF STA

XM Radio LLC (“XM Radio”) respectfully requests a 180-day extension of the

special temporary authority (“STA”) granted in File No. SAT-STA-20141017-00110, 1 which

extended the XM-1 satellite’s license term and authorized relocating XM-1 to 39° W.L. +/- 0.1

degrees in preparation for its retirement. In addition, XM Radio herein seeks authority to

remove XM-1 to a disposal orbit pursuant to a revised orbital debris mitigation plan that reflects

a higher level of residual xenon. Grant of the requested authority will serve the public interest by

facilitating the orderly retirement of XM-1 beginning in October 2015.

Background

XM-1 is currently positioned at 115.25º W.L. with a +/- 0.1 degree east-west

stationkeeping tolerance, where it had been serving as an in-orbit spare. 2 As the Commission is

aware, XM Radio began preparations for retirement of both XM-1 and XM-2 in 2013, working

closely with both the International Bureau’s Satellite Division and Boeing Satellite Systems

(“BSS”), the satellites’ manufacturer. XM Radio has explained that the retirement planning

1
See XM Radio LLC, Call Sign S2118, File No. SAT-STA-20141017-00110 (the “XM-1
Relocation STA”), grant-stamped Nov. 26, 2014.
2
See XM Radio LLC, Call Sign S2118, File No. SAT-MOD-20101216-00262 (the “XM-1
Modification”), grant-stamped Mar. 8, 2011 (the “XM-1 Modification Grant”).

process was especially complex because XM-1 and XM-2 are the first satellites in the XM Radio

fleet and the first spacecraft in the BSS 702 product line to be removed to a disposal orbit. 3

Furthermore, XM Radio has access to limited ground resources that are equipped to

communicate with these satellites and have the tracking capabilities needed to support the

satellite orbit raising and decommissioning process. 4

XM Radio proposed to drift both XM-1 and XM-2 significantly eastward before

beginning orbit-raising maneuvers in order to keep the satellites within range of its earth station

network for a longer period during the decommissioning process. XM Radio advised the

Commission that it would perform the necessary maneuvers for XM-2 first, and would start the

drift of XM-1 eastward only after it had completed the orbit raising process for XM-2. 5 XM

Radio explained that this sequencing would allow XM Radio to make any appropriate

adjustments to the XM-1 plan based on the results of the XM-2 satellite decommissioning and

would permit use of the same ground facilities to support the maneuvers of both satellites. 6

Pursuant to Commission authority, 7 XM-2 was relocated to 27° W.L. and held

there during venting of onboard propellant, and the satellite was subsequently raised to a disposal

3
XM-1 Relocation STA, Narrative at 1.
4
Id. at 1-2.
5
Id. at 2.
6
Id.
7
See XM Radio LLC, Call Sign S2119, File Nos. SAT-STA-20140204-00018, grant-stamped
Mar. 28, 2014; SAT-STA-20140922-00103 (“XM-2 September STA Request”), grant-stamped
Sept. 26, 2014 (“XM-2 September STA Grant”); and SAT-STA-20141017-00109, grant-stamped
Oct. 23, 2014.

2

orbit last October. 8 XM Radio had originally planned to drift XM-1 to 27° W.L. as well, but

lessons learned from the XM-2 drift led XM Radio to specify 39° W.L., rather than 27° W.L., as

the location at which XM-1 will be prepared for orbit raising. 9

Like XM-2, XM-1 has both a traditional liquid bi-propellant system that was used

for initial orbit raising and an electric xenon ion propulsion system (“XIPS”) used for

stationkeeping while in orbit. During the retirement process for XM-2, XM Radio found that the

process of depleting the extra xenon on board the spacecraft was extremely time-consuming. In

order to avoid significant delay in the schedule for raising XM-2 to a disposal orbit, XM Radio

requested and received Commission authority to retire the satellite pursuant to a revised orbital

debris mitigation plan reflecting higher predicted levels of residual xenon on the spacecraft at

end of life. 10 The Commission approved the updated plan reflecting the higher xenon levels

based on the practical obstacles to attempting to vent a greater proportion of the xenon, the

public interest in removing a satellite from geostationary orbit when it can no longer perform its

primary mission, and the fact that the other elements of the plan, including the proposed disposal

orbit altitude, remained unchanged. 11

With the XM-2 retirement complete, relocation of XM-1 in preparation for its

orbit raising will begin within the next few months. XM Radio anticipates commencing the drift

to 39° W.L. in mid-June 2015 when the required ground facilities to support the drift become

available. Drift is expected to take two months. After the satellite arrives at 39° W.L., it will be

8
See Letter of Karis A. Hastings, Counsel for XM Radio LLC, to Marlene H. Dortch,
Secretary, Federal Communications Commission, File No. SAT-STA-20141017-00109, dated
Oct. 30, 2014.
9
XM-1 Relocation STA, Narrative at 2-4.
10
See XM-2 September STA Grant, ¶ 6.
11
See id.

3

maintained there during venting of excess xenon and bi-propellant. In order to facilitate power

management, orbit-raising will not commence until mid-October 2015, after the fall eclipse

season ends.

Request for Extended Operating and Drift Authority

XM Radio requests extension of the XM-1 Relocation STA for a further 180-day

period. Grant of the requested extension of the XM-1 license authority will allow XM Radio to

relocate the spacecraft eastward, vent excess propellant, and remove the satellite to a disposal

orbit.

Revised Orbital Debris Mitigation Plan

XM Radio seeks Commission authorization to proceed with the retirement of

XM-1 pursuant to the updated orbital debris mitigation plan described herein to prevent

significant delay in the planned retirement schedule. The designs of XM-1 and XM-2 are

identical, and authorizing orbit raising of XM-1 under the modified plan is therefore consistent

with the XM-2 September STA Grant.

As with XM-2, XM Radio had previously submitted information provided by BSS

indicating that approximately 2.2 kg (2200 grams) of xenon would remain in each of the two

xenon tanks onboard XM-1 at end of life. 12 Based on this data and given the fact that XM-1 was

designed and launched prior to the Commission’s adoption of its orbital debris mitigation

requirements, the Commission granted XM Radio a waiver of the Section 25.283(c)

requirements to vent excess propellant and relieve pressure vessels in connection with the

12
See Call Sign S2118, File No. SAT-MOD-20101216-00262, Technical Appendix at 4
(explaining that the xenon tanks are equipped with a regulator that prevents additional gas from
being vented once the pressure falls below the set point of the regulator), grant-stamped Mar. 8,
2011.

4

residual xenon then expected to be on XM-1 at end of life. 13 XM Radio now projects instead

that 18-22 kg of residual xenon will remain in each tank at end of life. Approving the revised

plan with respect to residual xenon and granting an updated waiver of Section 25.283(c) would

be in the public interest in light of the specific circumstances here.

The facts underlying the increased residual xenon estimate for XM-1 are identical

to those described in the XM-2 September STA Request. 14 First, like XM-2, XM-1 is being

retired early due to performance issues outside of XM Radio’s control, and the shortened useful

life of the satellite reduced the amount of xenon used during the satellite’s operational lifetime,

leading to a higher level of residual xenon at the beginning of the disposal process.

Furthermore, XM Radio’s experience with XM-2 indicates that only a limited

portion of the onboard xenon can be vented during XM-1’s stay at 39° W.L. XM Radio found

that reconfiguring the XIPs system between venting and use for regular stationkeeping

maneuvers was much more complicated and time-consuming than anticipated, significantly

reducing the time that could be spent venting the xenon each day. 15

It is not possible to continue venting xenon after XM-1 is decommissioned.

Again, reliable ground resources operating with the S- and X-band frequencies used by XM-1

and the tracking capabilities needed to support the orbit-raising maneuvers and decommissioning

are extremely limited. As a result, once the orbit-raising begins, XM Radio will have a restricted

window of time before the satellite’s westward drift takes it beyond the range of the ground

network. Decommissioning the satellite requires sending commands to drain the batteries and

turn off all active units – steps that must be taken before the ground antennas lose contact with
13
See XM-1 Modification Grant, Attachment to Grant at 2, ¶ 6.
14
XM-2 September STA Request, Narrative at 3-5.
15
See id. at 3-4.

5

$the satellite. Because opening the valves to the xenon tanks requires power, the valves will close and remain closed once the power to the satellite is terminated. 16 Maintaining XM-1 at 39° W.L. to vent additional xenon before beginning orbit- raising maneuvers would materially delay the satellite’s retirement. Rather than being able to commence the retirement process in mid-October as planned, XM Radio would have to put off the orbit-raising until mid-April of 2016, given the time needed to significantly reduce the xenon levels and the delay required by the spring eclipse season. In order to maintain the current schedule to begin orbit raising this October, XM Radio seeks Commission authority to proceed under the revised orbital debris mitigation plan and requests a waiver of Section 25.283(c) to reflect the increased residual xenon. As XM Radio showed with respect to XM-2, the additional xenon does not increase the risk of orbital debris. 17 With 18-22 kg of xenon, the pressure in each tank will be 3.7-4.2 MPa assuming a temperature of 20° Celsius. This pressure represents a small fraction (12-14%) of the 30.1 MPa for which the tanks have been proof pressure tested and will drop further as the temperature on the spacecraft decreases following shut-down of its electrical systems. Because the xenon is inert, having the higher levels of residual xenon on board the spacecraft at its end of life should pose no risk of chemical energy release. Furthermore, the tanks are well shielded and will be isolated from any source of electrical energy. XM Radio emphasizes that nothing has changed with respect to XM Radio’s plan to raise XM-1 to a disposal orbit at least 313 km above the geostationary arc, which is the altitude derived by application of the IADC standard. 18 16 See id. at 4. 17 See id. at 5. 18 See Call Sign S2118, File No. SAT-AMD-20080129-00031, Amendment Narrative at 3-4, grant-stamped Feb. 14, 2008. 6$

Under these circumstances, the public interest would be served by permitting

retirement of XM-1 to go forward as requested herein, rather than requiring venting of additional

xenon. Accordingly, XM Radio respectfully requests special temporary authority for a period of

180 days commencing on May 26, 2015, to extend the XM-1 license term and drift authority and

to allow retirement of the satellite to proceed in accordance with the updated orbital debris

mitigation plan discussed herein.

Respectfully submitted,

XM Radio LLC

/s/ James S. Blitz
Of Counsel James S. Blitz
Karis A. Hastings Vice President, Regulatory Counsel
SatCom Law LLC XM Radio LLC
1317 F Street, N.W., Suite 400 1500 Eckington Place, N.E.
Washington, D.C. 20004 Washington, D.C. 20002
(202) 599-0975 (202) 380-4000

Dated: March 17, 2015

7

Technical Certification

I, Bridget Neville, Vice President and General Manager for Satellite Engineering

and Operations of Sirius XM Radio Inc., hereby certify under penalty of perjury that:

I am the technically qualified person with overall responsibility for preparation of

the technical information contained in the foregoing STA request. I am familiar with the

technical requirements of Part 25 of the Commission’s rules, and the information contained in

the request is complete and accurate to the best of my knowledge, information and belief.

_________/s/___________
Bridget Neville

Dated: March 17, 2015

Document Created: 2015-03-17 16:37:11
Document Modified: 2015-03-17 16:37:11