Attachment Exhibit B

This document pretains to SAT-PDR-20190321-00018 for Petition for Declaratory Ruling on a Satellite Space Stations filing.

IBFS_SATPDR2019032100018_1638514

                                                                                                Exhibit B
                                                                                        Spire Global, Inc.
                                                                    47 C.F.R. § 25.114(d)(14) Submission

                     Spire Global, Inc. (“Spire”) Orbital Debris Risk Mitigation Plan

        Spire believes that (i) MINAS satellites create relatively little additional orbital debris

risks compared to existing systems approved by the Federal Communications Commission

(“Commission”) and (ii) these satellites meet applicable orbital debris requirements as listed in

Section 25.114(d)(14) of the Commission’s rules.1

             •   Spire will add a third solar “drag” panel on all of its MINAS satellites, increasing

                 the amount of drag on the satellites and shortening the orbital lifetimes by

                 between 0.50 and 0.75 years (dependent on solar cycle changes) from launch at

                 their highest orbit of 650 km.

             •   The MINAS satellite bus will have a nominal launch mass configuration of 4.5

                 kg; however, the mass capacity may be up to 6 kg maximum, which

                 accommodates potential other Spire or hosted payload(s). Surface area and

                 spacecraft specifications are otherwise identical. Both nominal and maximum

                 cases are included in the attached Orbital Debris Assessment Report (“ODAR”)

                 for collision risk and lifetime analyses.2

Each section below addresses specific measures taken by Spire, as required under Section

25.114(d)(14), to limit the possibility that its space station operations will generate orbital debris.

        Like the Phase I, Phase IB, Phase IC, and Phase II satellites, MINAS satellites continue

to be one of the lowest risk satellite busses ever approved by the Commission.




1 See 47 C.F.R § 25.114(d)(14); see also Orbital Debris Assessment Report: MINAS Satellites, Exhibit C (“Exhibit
C”).
2 See Exhibit C.




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                                                                                               Exhibit B
                                                                                       Spire Global, Inc.
                                                                   47 C.F.R. § 25.114(d)(14) Submission

    I.      Orbital Dwell and Post-Mission Disposal

         The Commission’s rules call for indication of the anticipated evolution over time of the

satellites’ orbits.3 Specifically, using the National Aeronautics and Space Administration

(“NASA”) Debris Assessment Software (“DAS”), Spire has calculated the dwell times of the

MINAS satellites.

         At the highest orbit sought of 650 km, total orbital lifetime would not exceed 21.8 years

from launch in a conservative worst-case scenario. This calculation is based on a conservative

worst-case scenario of a dead-on-arrival MINAS satellite, launched in its maximum mass

configuration,4 and is still well within the standard of twenty-five years of mission completion

and thirty years of launch set forth in Requirement 4.6.1 of NASA-STD-8719.14A

(“Requirement 4.6.1”).5 This analysis is more conservative than the analysis conducted by most

other operators, who do not calculate orbital dwell time and do not limit themselves to an orbit

based on a worst-case, dead-on-arrival basis.6 The actual expected lifetime is seven to fourteen

years at this worst-case altitude, depending on the initial mass of the satellite.

         Spire has run an analysis measuring dwell times at inclinations from equatorial to sun

synchronous to ensure that changes in inclination do not cause Spire to violate Requirement 4.6.1

at a maximum deployment apogee of 650 km. The results indicate that changes in inclination do

not meaningfully affect orbital dwell times and that at any inclination at 650 km the 25-year

requirement is met.7


3 See 47 C.F.R. § 25.114(d)(14)(iii).
4 As mentioned, MINAS satellites have a nominal launch configuration of 4.5 kg; however, the mass capacity may
be up to 6 kg maximum to accommodate any hosted payload scenarios. Both nominal and maximum cases are
included in the ODAR for collision risk and lifetime analyses. See Exhibit C.
5 See Process for Limiting Orbital Debris, NASA-STD-8719.14A § 4.6.1 (Dec. 2011).
6 As of today, no LEMUR-2 or MINAS satellite has been dead on arrival.
7 See NASA-STD-8719.14A § 4.6.1; see also Mitigation of Orbital Debris, Second Report and Order, 19 FCC Rcd

11567 ¶¶ 61, 83 (2004).


                                                       2


                                                                                       Exhibit B
                                                                               Spire Global, Inc.
                                                           47 C.F.R. § 25.114(d)(14) Submission


          Orbital Lifetime (years) vs. Altitude & Inclination (km)
                                                                                      SSO
     30
                                                                                      Equatorial
     25
                                                                                      10 deg
     20




                                                                  Max Altitude
                                                                                      20 deg
     15                                                                               30 deg
     10                                                                               40 deg

      5                                                                               50deg
                                                                                      60 deg
      0
           375 400 425 450 475 500 525 550 575 600 625 650 675 700                    70 deg
                                  Altitude (km)                                       80 deg
                                                                                      90 deg




       Spire has also run an analysis measuring dwell times across the entire solar cycle to

ensure that changes in launch schedule do not cause Spire to violate Requirement 4.6.1 at a

maximum deployment apogee of 650 km.




                                                3


                                                                                          Exhibit B
                                                                                  Spire Global, Inc.
                                                              47 C.F.R. § 25.114(d)(14) Submission




           The dwell times for all orbits under 650 km are predictably less than the 650 km orbit,

meeting Requirement 4.6.1. Full details of the NASA DAS analysis with respect to orbital dwell

times for all deployments sought by Spire with respect to the MINAS satellites are contained in

the ODAR.8

           To ensure that Spire exceeds the NASA standard in all scenarios, Spire has included a

double fault-tolerant solar panel deployment mechanism, which will provide sufficient surface

area and drag to comply with the NASA standard even if a MINAS satellite is dead on arrival.

This deployment mechanism is the same as the one installed on board the Phase I and Phase II

satellites previously approved by the Commission. These satellites’ solar panels are part of a

built-in, post-deployment sequence programed into onboard software prior to launch, which

requires no direction from the ground. If for some reason the onboard sequence fails, solar array

deployment can be commanded from the ground. If a satellite is non-communicative, an entirely

8   See Exhibit C.


                                                   4


                                                                                              Exhibit B
                                                                                      Spire Global, Inc.
                                                                  47 C.F.R. § 25.114(d)(14) Submission

passive and redundant fail-safe is included on all satellites in the form of a burn wire. The

tensile strength of the burn wire has been tested and verified to degrade to a breaking point after

3600 hours or 150 days of UV radiation exposure.9 Spire’s worst-case scenario for dwell time

conservatively models five years of non-deployed solar panels and no loss of altitude during

those five years even though a dead-on-arrival satellite still has surface area that would cause at

least some altitude loss.

    II.       Re-entry Hazards

           Spire’s post-mission disposal plan is to allow its satellites to passively re-enter the

atmosphere and completely burn up upon re-entry.10 Spire has used NASA DAS to review the

survivability of major components upon re-entry and found that no objects are expected to

survive re-entry, putting the risk to human life (both on the ground and in aircraft) at 0. This

calculation is orders of magnitude lower than legacy satellite busses.

    III.      Planned Release of Debris

           Spire’s MINAS satellites will not undergo any planned release of debris. Spire also

conducts extensive acceptance level environmental testing of all of its satellites to provide

further confidence in the structural integrity of the satellite in launch and space environments. In

fact, because Spire launches with every major launch rocket that takes secondary payloads,

including Falcon 9; Antares/Cygnus; Atlas-5; PSLV; Soyuz; and H-II, the satellite will be

subjected to a battery of different testing standards, including those required by NASA for

International Space Station (“ISS”) deployments.




9 See Application of Spire Global, Inc., File No. SAT-LOA-20151123-00078, Test Summary: Tensile Properties
Test with Accelerated UV Aging A Demonstration of NOAA DeOrbit Guideline Compliance in an ‘Edge Case’
Scenario, Exhibit E (filed Nov. 23, 2015).
10 See 47 C.F.R. § 25.114(d)(14)(iv).




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                                                                                              Exhibit B
                                                                                      Spire Global, Inc.
                                                                  47 C.F.R. § 25.114(d)(14) Submission

     IV.      Limiting the Probability of Accidental Explosions

           MINAS satellites have no propulsion and accordingly do not carry highly volatile rocket

propellant. The only energy sources (kinetic, chemical, or otherwise) onboard the spacecraft is a

Lithium-Ion battery system and reaction wheels.

           The battery pack on board the MINAS satellites complies with all controls/process

requirements identified in NASA Report JSC-20793 Section 5.4.3 to mitigate the chance of any

accidental venting/explosion.11 A battery cell protection circuit manages the charging cycle,

performs battery balancing, and protects against over and undercharge conditions. The batteries

will not be passivated at End-of-Mission due to the low risk and low impact of explosive

rupturing. The maximum total chemical energy stored in the battery pack is ~144kJ (~288kJ

total).

           The only failure mode of the reaction wheel assemblies that could lead to creation of

debris would be breakup of the wheels themselves due to mechanical failure while operating at a

high angular rate. Risk mitigation strategies for breakups due to the reaction wheels include

limiting the maximum rotational speed of the wheels and containing them within a sealed

compartment.

     V.       Collisions with Large Debris

           The collision risk posed by the MINAS satellites continues to be among the lowest in the

satellite industry due to their very small surface area and mass. Using NASA DAS, Spire has

calculated the risk of collision for all deployments sought in this application. The highest

probability of collision occurs for the highest orbit of 650 km. Even that probability is 1 x 10-5



11 See Crewed Space Vehicle Battery Safety Requirements, NASA Report JSC-20793 § 5.4.3 (Jan. 2014),
https://standards.nasa.gov/file/657/download?token=DUcHF-J7.


                                                      6


                                                                                             Exhibit B
                                                                                     Spire Global, Inc.
                                                                 47 C.F.R. § 25.114(d)(14) Submission

over its entire orbital lifetime for a fully deployed satellite (i.e., the maximum surface area).12

This probability is hundreds of times lower than legacy satellite busses’ probability of collision

in their worst-case orbits. Full details of the NASA DAS analysis with respect to collision with

large objects for each deployment sought in this application are contained in the ODAR attached

to this application.13

        Spire participates in a sharing agreement with the Joint Space Operations Center

(“JSpOC”) to better coordinate collision avoidance measures and receive conjunction threat

reports. Spire’s satellites carry onboard Global Positioning System (“GPS”) receivers that

provide for precise orbital position determination. Spire also receives from JSpOC updated two-

line element sets, or “TLEs,” which facilitate the identification and tracking of Spire’s satellites.

JSpOC has a direct line to Spire’s satellite operations team that is accessible twenty-four hours

per day/seven days per week to ensure that Spire can take immediate action to coordinate

collision avoidance measures. Spire’s GPS-Radio Occultation instrument has capabilities that

allow it to determine the precise location of a satellite down to two centimeters. To Spire’s

knowledge, such precise location capabilities are non-existent outside the context of very large

government satellites and do not exist for any commercial operator.14 This hyper-precise

location data will allow the satellites to have orbits projected out with extreme precision, thus

greatly lowering the number of false positive conjunction alerts and making collision avoidance

measures far more well informed. Spire currently provides ephemeris data, available from




12 See Exhibit C.
13 See id.
14 For reference, Spire’s agreement with Orbcomm License Corp. specifies location accuracy of 20 meters as a

threshold. See Application of Spire Global, Inc., File No. SAT-LOA-20151123-00078, Spire Global - ORBCOMM
Agreement (filed Sept. 15, 2016). TLEs received from JSpOC have accuracy measured in kilometers.


                                                     7


                                                                                                  Exhibit B
                                                                                          Spire Global, Inc.
                                                                      47 C.F.R. § 25.114(d)(14) Submission

public sources, online.15 In the near future, Spire will begin publicly sharing enhanced

ephemeris data, using the hyper-precise location data from its proprietary GPS-Radio

Occultation instrument.

           Special care is also given to minimizing the potential for collision with manned

spacecraft, including the ISS. The operational altitude of the ISS is approximately 400 km.

Spire will coordinate with NASA to assure protection of the ISS on an ongoing basis. Because

Spire participates in many ISS deployments (including above station deployments expressly

approved by the ISS program on a launch-by-launch basis), ISS program management has a

detailed understanding of the MINAS satellites.

           Spire will work closely with its launch providers to ensure that the satellites are deployed

in such a way as to minimize the potential for in-plane collision. The risk is further mitigated

with the typical small deployments undertaken by Spire.

           Further, in advance of this filing, Spire has reached out to the other low-Earth orbit

operators at or below 650 km that are identified in the Commission’s Approved Space Station

List and has informed them of Spire’s intention to coordinate to further mitigate any collision

risks.16

           The Commission’s rules call upon applicants to specify the accuracy, if any, with which

the orbital parameters of their non-geostationary satellite orbit space stations will be

maintained.17 Because the MINAS satellites will not carry maneuvering propellant, Spire will

not maintain satellite inclination angles, apogees, perigees, and right ascension of the ascending

node to any specified degrees of accuracy.

15 See Open TLE Service, Spire, tle.spire.com (last viewed Feb. 21, 2016). To obtain the ephemeris data for any
particular satellite, type in the satellite’s NORAD ID after “tle.spire.com/” in the URL bar.
16 See Approved Space Station List, FCC, https://www.fcc.gov/approved-space-station-list (last updated Dec. 3,

2018).
17 See 47 C.F.R § 25.114(d)(14)(iii).




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                                                                                                Exhibit B
                                                                                        Spire Global, Inc.
                                                                    47 C.F.R. § 25.114(d)(14) Submission

       VI.      Collisions with Small Debris or Meteoroids

             Spire used NASA DAS to confirm that the MINAS satellites meet the requirements of

4.5-2.18




18   See Process for Limiting Orbital Debris, NASA-STD-8719.14A § 4.5-2 (Dec. 2011).


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Document Created: 0930-04-27 00:00:00
Document Modified: 0930-04-27 00:00:00

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