AC7 AC5 ODAR v5

0072-EX-ML-2015 Text Documents

Aerospace Corporation, THE

2015-07-09ELS_164510

AeroCube-7 / 5c ODAR                                              The Aerospace Corporation


                          AeroCube-7 + AeroCube-5c
             Orbital Debris Assessment Report (ODAR)
                          Report Version: 1.3, 14 March 2013


    Prepared for NASA in compliance with NPR 8715.6A by The Aerospace Corporation.

                    Software used in this analysis: NASA DAS v2.0.2



Revision       Date               Pages            Description                 Author
  1.0       10 Sep 2013      14 + appendices       First version,           J. Gangestad,
                                                requires signatures     Astrodynamics Dept.
   1.1      12 Sep 2013      14 + appendices     Signatures added,          J. Gangestad,
                                                 minor corrections      Astrodynamics Dept.
   1.2      14 Feb 2014      15 + appendices     Update for CDR             J. Gangestad,
                                                                        Astrodynamics Dept.
   1.3      14 Mar 2014      15 + appendices    Minor corrections           J. Gangestad,
                                                   from CDR             Astrodynamics Dept.
   2.0       1 Nov 2014      17 + appendices     Updating for public        D. Hinkley
                                                       release           PICOSAT Program
   3.0       2 Feb 2015      17 + appendices     Change to GRACE            D. Hinkley
                                                launch from UltraSat     PICOSAT Program
                                               launch; Swap out one
                                                 AeroCube-7 for an
                                                    AeroCube-5c
   4.0      15 Apr 2015      16 + appendices     Updated per change         D. Hinkley
                                                      requests           PICOSAT Program
   5.0       9 Jun 2015      15 + appendices   Updated debris section       D. Hinkley
                                                                         PICOSAT Program




                                      Page 1 of 15


AeroCube-7 / 5c ODAR                                                  The Aerospace Corporation




                     VERSION APPROVAL and FINAL APPROVAL*:




          The Aerospace Corporation




          Dr. Siegfried Janson
          AeroCube-7
          Principal Investigator
          The Aerospace Corporation




          Dr. Richard Welle
          AeroCube-7
          Program Manager
          The Aerospace Corporation




          Dr. James Nokes
          Principal Director
          Space Materials Laboratory
          The Aerospace Corporation


* Approval signatures indicate acceptance of the ODAR-defined risk.

** Signatures required only for Final ODAR




                                        Page 2 of 15


AeroCube-7 / 5c ODAR                                                                               The Aerospace Corporation




Self-Assessment of Requirements per NASA-STD 8719.14A
                                                                                               Compliance
Requirement                                                                                                 Comments
                                                                                               Assessment
         All debris released during the deployment, operation, and disposal phases shall
4.3-1a   be limited to a maximum orbital lifetime of 25 years from date of release.             Compliant   6.5 years (DAS2.02)
         The total object-time product shall be no larger than 100 object-years per                         65 object-years
4.3-1b   mission.                                                                              Compliant    (DAS2.02)
         For missions leaving debris in orbits with the potential of traversing GEO,
         released debris with diameters of 5 cm or greater shall be left in orbits which
4.3-2    will ensure that within 25 years after release the apogee will no longer exceed       Compliant    N/A-LEO mission
         GEO-200 km.
                                                                                                            On board energy
         For each spacecraft a employed for a mission, the program or project shall
                                                                                                            source (batteries)
4.4-1    demonstrate…that the integrated probability of explosion for all credible             Compliant
         failure modes of each spacecraft is less than 0.001.                                               incapable of debris-
                                                                                                            producing failure
         Design of all spacecraft shall include the ability and a plan to deplete all                       On board energy
         onboard sources of stored energy and disconnect all energy generation sources
                                                                                                            source (batteries)
4.4-2    when they are no longer required for mission operations or post-mission               Compliant    incapable of debris-
         disposal or control to a level which cannot cause an explosion or deflagration
         large enough to release orbital debris or break up the spacecraft.                                 producing failure
         Planned explosions or intentional collisions shall: a) be conducted at an
         altitude such that for orbital debris fragments larger than 10 cm the object-time
4.4-3    product does not exceed 100 object-years, and b) not generate debris larger           Compliant    No planned breakups.
         than 1 mm that remains in Earth orbit longer than one year.
         Immediately before a planned explosion or intentional collision, the probability
4.4-4    of debris, orbital or ballistic, larger than 1 mm colliding with any operating        Compliant    No planned breakups.
         spacecraft within 24 hours of the breakup shall be verified to not exceed 10-6.
         For each spacecraft in or passing through LEO, the program shall demonstrate
4.5-1    that, during the orbital lifetime of each spacecraft, the probability of accidental   Compliant    DAS2.02
         collision with space objects larger than 10 cm in diameter is less an 0.001.
         For each spacecraft, the program shall demonstrate that, during the mission of
         the spacecraft, the probability of accidental collision with orbital debris and
4.5-2    meteoroids sufficient to prevent compliance with the applicable post-mission          Compliant    DAS2.02
         disposal requirements is less than 0.01.
         A spacecraft with a perigee altitude below 2000 km shall be disposed of by one
         of the following three methods: a) leave the space structure in an orbit in
         which natural forces will lead to atmospheric reentry within 25 years, b)
4.6-1    maneuver the space structure into a controlled de-orbit trajectory, c) maneuver       Compliant    DAS2.02
         the space structure into an orbit with perigee altitude above 2000 km and
         apogee less than GEO-500 km.
         A spacecraft or orbital stage in an orbit near GEO shall be maneuvered at EOM
4.6-2    to a disposal orbit above GEO.                                                        Compliant    N/A-LEO mission
         For space structures between LEO and GEO, a spacecraft shall be left in an
         orbit with a perigee greater than 2000 km above the Earth’s surface and apogee
4.6-3    less than 500 km below GEO, and a spacecraft shall not use nearly circular            Compliant    N/A-LEO mission
         disposal orbits near regions of high-value operational space structures.
         NASA space programs shall ensure that all post-mission disposal operations to
4.6-4    meet the above requirements are designed for a probability of success of no           Compliant    Passive disposal
         less than 0.90 at EOM.
         For uncontrolled reentry, the risk of human casualty from surviving debris
4.7-1    shall not exceed 0.0001.                                                              Compliant    DAS2.02
         Intact and remnants of severed tether systems in Earth orbit shall meet the
4.8-1    requirements limiting the generation of orbital debris from on-orbit collisions       Compliant    No tethers
         and the requirements governing post-mission disposal.



NOTE: When manifested for flight, AeroCube-7 will fly as a secondary payload. Compliance
with requirements levied by NASA-STD 8719.14A on the launch vehicle will be the
responsibility of the primary payload and/or launch provider.


                                                             Page 3 of 15


AeroCube-7 / 5c ODAR                                                  The Aerospace Corporation


Section 1: Program Management and Mission Overview
Mission Directorate: Space Technology Mission Directorate

Program Executive: Andrew Petro

Principal Investigator: Siegfried Janson, The Aerospace Corporation

Program Manager: Richard Welle, The Aerospace Corporation

Foreign government or space agency participation: none

Nominal Schedule of Mission Design and Development:


Event                                       Date
Project initiation                       1 Oct 2012
System Requirements Review (SRR)         4 Mar 2013
Preliminary Design Review (PDR)         19 Sep 2013
Critical Design Review (CDR)            13 Mar 2014
System integration begins               26 Mar 2014
Test Readiness Review (TRR)              1 Dec 2014
System integration complete             15 Feb 2015
Flight Readiness Review (FRR)           15 Mar 2015
Delivery                                23 Mar 2015
Target launch date                      1 Aug 2015



Brief Description of the Mission:

This mission will consist of one AeroCube-7 (2.2 kg) and one AeroCube-5c (2 kg) Nano class
satellite, each about 4x4x6 inches in dimension to be simultaneously ejected from a single tube
that will be lifted into a 500 km x 780 km with 64 degree inclination orbit on an Atlas V vehicle
planned for August 2015. The two satellites will not collide and will separate naturally from
each other due the slight difference in their balistic coefficients. The mission of AeroCube-7 will
perform its mission of demonstrating laser communications from space to the Mt. Wilson optical
ground station on earth and the AeroCube-5c will separately perform tracking experiments.

The AeroCube-7, also known as the Optical Communications and Sensor Demonstration
(AeroCube-OCSD) mission will demonstrate the: high-speed optical transmission of data: 20-
Mbytes over 60-seconds with a bit error rate (BER) of 10-4 or better to a 30-cm diameter
telescope from low Earth orbit (LEO). AeroCube-5c will study tracking of the AC7. It is a
repeat to a prior mission (call sign WG2XVZ). This flight demonstration will consist of one




                                           Page 4 of 15


AeroCube-7 / 5c ODAR                                                  The Aerospace Corporation


AeroCube-7- and one AeroCube-5c that are ejected from a CubeSat deployer. The two vehicles
will not be doing any proximity operations.

Identification of the anticipated launch vehicle and launch site: One AeroCube-7 and one
AeroCube-5c will fly as a secondary payload on a rideshare mission. They are currently
manifested in a P-POD on the NROL-55 Atlas V mission launching in Q3 CY2015. This launch
will deliver them to an approximately 500 x 780 km altitude orbit at an inclination of 64 deg.

Identification of the proposed launch date and mission duration: We anticipate a launch as a
secondary payload in Q3 CY2015. The mission duration is nominally 180 days.

Description of the launch and deployment profile: As a secondary payload, the AeroCubes
will be deployed from the launch vehicle to minimize risk to the primary payload and upper-
stage space structures. Depending on the launch provider, deployment may occur before or after
deployment of the primary payload. Typically, after deploying the primary payload, the upper
stage performs a small burn to alter the orbit (eliminating the risk of collision with the primary)
before releasing any secondary payloads.

Reason for selection of operational orbit: The orbit is selected for adequate mission lifetime
and the inclination is requested above 35 deg to ensure that the spacecraft pass over The
Aerospace Corporation’s ground stations in the continental United States.

Identification of any interaction or potential physical interference with other operational
spacecraft: The AeroCube-7 mission’s optical-communication objectives require the in-space
operation of a laser. All events planned with the AeroCube-7 laser system will be cleared with
the United States Air Force Laser Clearinghouse before operation to ensure no undesirable
illumination of other operational spacecraft. There is no planned relative proximity maneuvers
between AeroCube-7 and AeroCube-5c.

Section 2: Spacecraft Description
Physical Description:

The AeroCube-7 satellite is a one-and-a-half unit (1.5U) CubeSat with dimensions 10 x 10 x 15
cm. The vehicle has two wings that are deployed on orbit with dimensions of 10 x 15 cm. The
wing plane is parallel to the bus diagonal, as depicted in Figure 1.

The AeroCube-7 satellite contains multiple Sun sensors and Earth sensors, a star tracker, RF
communications antenna, GPS receiver, optical-beacon detector, fisheye camera, and narrow-
field camera. No components of the spacecraft except the wings extend beyond the dimensions
of the 1.5U bus.

The AeroCube-5c satellite is a one-and-a-half unit (1.5U) CubeSat with dimensions 10 x 10 x 15
cm. The vehicle (Figure 2) contains one Flight Computer system, one GPS system, one


                                           Page 5 of 15


AeroCube-7 / 5c ODAR                                             The Aerospace Corporation


Advanced Radio system, one Attitude control system, one optical beacon, and one Solar Power
system.




                          Figure 1. The AeroCube-7 spacecraft.




                           Figure 2: AeroCube-5 1.5U CubeSat



                                       Page 6 of 15


AeroCube-7 / 5c ODAR                                                              The Aerospace Corporation


More detail about AeroCube-5c is as follows:

          The Flight computer system is the central processing system of the satellite to coordinate
           commands between the subsystems.
          The GPS system will have a patch antenna and control electronics. It only receives.
          The Advanced Radio system will have a patch antenna and control electronics. It
           operates at 915 MHz and produces 1.3W.
          The Attitude control system will have triaxial reaction wheels, triaxial torque coils,
           triaxial magnetometers, one rate gyro, and earth and sun sensors.
          The beacon will have one beacon module, one MoliCel IBR18650B Lithium Ion battery
           and control electronics. It is 808 nm wavelength, 6 W in optical power and divergent (6
           degrees full-width-half-maximum). It acts like a flashlight.
          The Solar Power system will have two MoliCel ICR18650J Lithium Ion batteries and
           control electronics.
          The CSTT is a 12 meter long x 75 mm wide ribbon stowed under a panel on the outside
           of the spacecraft. This was taken off the AeroCube-5c spacecraft (but it had been on the
           prior versions – reference 0339-EX-PL-2013).


An exploded view of AeroCube-5c is shown in Figure 3.

                                               9

                                                                          6
                                                                              1




             2


                                     8
                                          7
       1    Antenna                                5
       2    Lid
       3    Electronics Module (EM) Assembly                          4
       4    STIM                                                              3
       5    Body Assembly
       6    CSTT (removed from AC5c)                                                     2
       7    Reaction wheel block                                                               1
       8    IMU
       9    Payload Assembly


                                   Figure 3: AeroCube-5c Expanded View




                                                       Page 7 of 15


AeroCube-7 / 5c ODAR                                                  The Aerospace Corporation


Total spacecraft mass (dry and wet) at launch: ~2.2 kg for AeroCube-7 and ~2.0 kg for
AeroCube-5c.

Description of all propulsion systems: Neither AeroCube-7 or AeroCube-5c has a propulsion
system for this mission.

Identification of all fluids planned to be on board: None.

Description of all active and/or passive attitude control systems with an indication of the
normal attitude of the spacecraft with respect to the velocity vector: Both the AeroCube-7
and AeroCube-5c spacecraft have 3-axis attitude control via three magnetic torquers and three
“pico” reaction wheels. The pico reaction wheels have flight heritage on three AeroCube-4 and
two AeroCube-5 spacecraft. Attitude sensors include eight infrared thermometer arrays on
various spacecraft surfaces, two-axis sun sensors on various spacecraft surfaces, a 3-axis
magnetometer in the main body, a 3-axis magnetometer and two or more experimental star
trackers (on AeroCube-7 only). A high-accuracy 3-axis rate gyro will be used to provide an
inertial attitude reference when 0.7 deg or better pointing accuracy is required and the sun and
Earth are not simultaneously visible by an appropriate sensor.

Description of any range safety or other pyrotechnic devices: Neither AeroCube-7 or
AeroCube-5c has pyrotechnic devices.

Description of the electrical generation and storage system: Power for AeroCube-7 is
generated by solar cells mounted on four faces of the spacecraft bus and on the two extended
wings. These cells are capable of producing up to 16 W of power. Power is stored on-board with
lithium-ion batteries. The bus power has redundant power circuits that each control and limit the
charging and discharging from a single 4.2V ICR18650H battery. Each circuit can produce up to
20W of power. The laser communications system battery consists of two 4.2V ICR18650B cells
in series, each with 6 W-hr. A power circuit controls this as a single battery and limits charging
and discharging.

Power for AeroCube-5c is generated by body mounted solar cells mounted on four faces of the
spacecraft bus. These cells are capable of producing up to 10 W of power. Power is stored on-
board with lithium-ion batteries. The bus power has redundant power circuits that each control
and limit the charging and discharging from a single 4.2V ICR18650H battery. Each circuit can
produce up to 10W of power. Specific details of the batteries’ manufacture appear in Section 4.

Identification of any other sources of stored energy: None on AeroCube-7 or AeroCube-5c.

Identification of any radioactive materials on board: None on AeroCube-7 or AeroCube-5c.




                                          Page 8 of 15


AeroCube-7 / 5c ODAR                                                   The Aerospace Corporation


Section 3: Assessment of Spacecraft Debris Released during Normal
Operations
The assessment of spacecraft debris requires the identification of any object (>1 mm) expected to
be released from the spacecraft any time after launch, including object dimensions, mass, and
material. Section 3 requires rationale/necessity for release of each object, time of release of each
object, relative to launch time, release velocity of each object with respect to spacecraft,
expected orbital parameters (apogee, perigee, and inclination) of each object after release,
calculated orbital lifetime of each object, including time spent in Low Earth Orbit (LEO), and an
assessment of spacecraft compliance with Requirements 4.3-1 and 4.3-2.

AeroCube-7 will release no objects into space during normal operations.

Analyses from the NASA DAS2.02 program predicts a lifetime product of <99 object-years
when calculating and adding together the lifetime of the AeroCube-7 and AeroCube-5c
spacecraft. This is acceptable because it is less than the 100 year limit listed in NASA-STD-
8719.14 Requirement 4.3-1b: “The total object-time product shall be no larger than 100 object-
years per mission.”

Rationale/necessity for release of each object: For AeroCube-5c only, tracking is part of the
science to be gathered.

Time of release of each object, relative to launch time: N/A.

Release velocity of each object with respect to spacecraft: N/A.

Expected orbital parameters (apogee, perigee, inclination) of each object after release: N/A.

Calculated orbital lifetime of each object, including time spent in LEO: N/A.

Assessment of spacecraft compliance with Requirements 4.3-1 and 4.3-2:

Requirement 4.3-1a: COMPLIANT

Requirement 4.3-1b: COMPLIANT

Requirement 4.3-2: COMPLIANT




                                           Page 9 of 15


AeroCube-7 / 5c ODAR                                                   The Aerospace Corporation


Section 4: Assessment of Spacecraft Intentional Breakups and
Potential for Explosion
Identification of all potential causes of spacecraft breakup during deployment and mission
operations: There is no credible scenario that would result in spacecraft breakup during normal
deployment and operations.

Summary of failure modes and effects analyses of all credible failure modes which may
lead to an accidental explosion:

Battery risk: A possible malfunction of the lithium ion or lithium polymer batteries or of the
control circuit has been identified as a potential, but low probability, cause of accidental breakup
or explosion. Natural degradation of the solar cells and batteries will occur over the post-mission
period and poses an increased chance of undesired battery-energy release. The battery capacity
for storage will degrade over time, possibly leading to changes in the acceptable charge rate for
the cells. Individual cells may also change properties at different rates due to time degradation
and temperature changes. The control circuit may also malfunction as a result of exposure over
long periods of time. The cell pressure relief vents could be blocked by small contaminants. Any
of these individual or combined effects may theoretically cause an electro-chemical reaction that
results in rapid energy release in the form of combustion.

Notwithstanding these potential sources of energy release, AeroCube-7 and AeroCube-5c still
meet Requirement 4.4-2 as the on-board batteries cannot “cause an explosion or deflagration
large enough to release orbital debris or break up the spacecraft.” The batteries are certified by
Underwriters Laboratories (UL). In general, these batteries are similar in size and power to cell-
phone batteries.

            Model Number                          Number
                                Manufacturer                  Energy Stored per Cell
             (UL Listing)                         of Cells
              ICR18650H            Molicel           2                 <8 W-hr
             IBR18650BC            Molicel           2                 <6 W-hr


The batteries are all consumer-oriented devices. The batteries have been recognized as UL tested
and approved. UL recognition has been determined through the UL Online Certifications
Directory, which clearly shows that these cell batteries have undergone and passed UL
Standards. Furthermore, safety devices incorporated in these batteries include pressure release
valves, over-current charge protection, and over-current discharge protection.

The fact that the batteries are UL recognized indicates that they have passed the UL standard
testing procedures that characterize their explosive potential. Of particular concern to NASA is
UL Standard 1642, which specifically deals with the testing of lithium batteries. Section 20
Projectile Test of UL 1642 subjects the test battery to heat by flame while within an aluminum-


                                          Page 10 of 15


AeroCube-7 / 5c ODAR                                                         The Aerospace Corporation


and steel-wire-mesh octagonal box, “[where the test battery] shall remain on the screen until it
explodes or the cell or battery has ignited and burned out” (UL 1642 20.5). To pass the test, “no
part of an exploding cell or battery shall penetrate the wire screen such that some or all of the
cell or battery protrudes through the screen” (UL 1642 20.1).

It is reasonable to expect the batteries to experience similar conditions during their orbital life
span. While the sources of failure would not be external heat on orbit, analysis of the expected
mission thermal environment shows that given the low power dissipation for CubeSats, the
batteries will be exposed to a maximum temperature well below their 212 deg F safe operation
limit. Continual charging from the solar panels over an orbital life span greater than 12 years
may expose the batteries to overcharging, which could cause similar heat to be generated
internally. Through the UL recognition and testing, it has been shown that these batteries do not
cause an explosion that would cause a fragmentation of the spacecraft.

In addition to the aforementioned certification of the batteries against explosion, ten potential
failure modes for lithium batteries and their applicability or mitigation in AeroCube-7 are
addressed in the following table:

    Failure Mode                        Applicability or Mitigation
                                        The AeroCube-7 or AeroCube-5c body and internal design
1   Internal short circuit              prevents deformation or crushing of the batteries that could lead
                                        to internal short circuit.
    Internal thermal rise due to high
2                                       See Failure Mode #4.
    load discharge rate
                                        The battery cells on AeroCube-7 have charge interrupt devices
    Overcharging and excessive          that activate during cell internal pressure buildup (due to cell
3
    charge rate                         internal chemical that forms a gas) that occurs during
                                        overcharging conditions.
                                        The bus batteries have an internal positive temperature coefficient
                                        (PTC) device that acts as a resettable fuse during external short
    Excessive discharge rate or         circuit that limits the cell output current during such an event. The
4   short circuit due to external       laser (i.e., payload) batteries are of mixed-spinel chemistry and do
    device failure                      not have such an internal device due to their high-rate capability;
                                        they have been tested in the lab to verify no cell rupture, venting,
                                        fire, or explosion occurs during external short circuit conditions.
                                        Vents have access through the structure that holds them and into
5   Inoperable vents                    the larger satellite volume. Venting will not be inhibited by
                                        physical obstructions.
6   Crushing                            Satellite body and internal design prevent loads on battery cases.
    Low level current leakage or
    short circuit through battery
7                                       Satellites are stored in a controlled environment.
    pack case or due to moisture-
    based degradation of insulators
                                        Thermal sensors on the batteries provide telemetry on battery
    Excess temperatures due to
                                        temperature. There is no cutoff for overheating batteries except
8   orbital environment and high
                                        whatever is inherent in the cell itself. However, as noted earlier in
    discharge combined
                                        this section of the ODAR, the batteries on AeroCube-7 are UL-



                                             Page 11 of 15


AeroCube-7 / 5c ODAR                                                       The Aerospace Corporation

                                       certified as non-explosive in over-heating scenarios.
     Polarity reversal due to over-    A 2.7 V discharge cutoff threshold circuit in AeroCube-7 has
9
     discharge                         been verified in acceptance tests for the electric power system.
     Excess battery temperatures due
     to post-mission orbital           The circuit that charges the batteries cannot exceed 4.1 V and
10
     environment and constant          therefore will never overcharge the batteries.
     overcharging


Through a combination of UL certification, compliance with AFSPCMAN 91-710 V3
requirements, and an understanding of the general behavior of the failure modes associated with
these types of batteries, it is possible to conclude that the batteries meet Requirement 4.4-2.

Propulsion-system risk: None

Detailed plan for any designed breakup, including explosions and intentional collisions:
AeroCube-7 and AeroCube-5c have no plans for intentional breakups, explosions, or collisions.

List of components which are passivated at EOM: No systems on AeroCube-7 will be
passivated at EOM. No systems on AeroCube-5c require passivation at EOM.

Rationale for all items which are required to be passivated, but cannot due to their design:
As described above, the batteries do not present a debris-generation hazard per Requirement 4.4-
2, and in the interest of not increasing the complexity of the AeroCube-7 or the AeroCube-5c
power systems, it was decided not to passivate the batteries at EOM.

Assessment of spacecraft compliance with Requirements 4.4-1 through 4.4-4:

Requirement 4.4-1: COMPLIANT

Requirement 4.4-2: COMPLIANT

Requirement 4.4-3: COMPLIANT

Requirement 4.4-4: COMPLIANT

Section 5: Assessment of Spacecraft Potential for On-Orbit
Collisions
Collision probabilities have been calculated using DAS v2.0.2 for a 500 x 780 km altitude, 64
deg inclination orbit containing one AeroCube-7 satellite and one AeroCube-5c satellite.

Calculation of spacecraft probability of collision with space objects larger than 10 cm in
diameter during the orbital lifetime of the spacecraft: Probability = 0.00000, per DAS v2.0.2




                                            Page 12 of 15


AeroCube-7 / 5c ODAR                                               The Aerospace Corporation


Calculation of spacecraft probability of collision with space objects, including orbital
debris and meteoroids, of sufficient size to prevent post-mission disposal: Both AeroCube-5c
and AeroCube-7 do not have or need active mission disposal capability.

Assessment of spacecraft compliance with Requirements 4.5-1 and 4.5-2:

Requirement 4.5-1: COMPLIANT

Requirement 4.5-2: COMPLIANT

Section 6: Assessment of Spacecraft Postmission Disposal Plans and
Procedures
Description of spacecraft disposal option selected: Passive.

Although in practice after EOM the vehicle will tumble with a higher “average” cross-sectional
area, the analysis in DAS assumed the worst-case low-drag configuration for lifetime. DAS
calculates a lifetime of 18 yr for AeroCube-7 and 21 yr for AeroCube-5c, using the orbit
assumptions listed at the beginning of Section 5. This lifetime is compliant with ODAR
requirements.

Identification of all systems or components required to accomplish any post-mission
disposal operation, including passivation and maneuvering: Natural orbit decay is sufficient
to terminate the mission.

Plan for any spacecraft maneuvers required to accomplish post-mission disposal: None

Calculation of area-to-mass ratio after post-mission disposal, if the controlled reentry
option is not selected: N/A

Preliminary plan for spacecraft controlled reentry: N/A

Assessment of compliance with Requirements 4.6-1 through 4.6-4:

Requirement 4.6-1: COMPLIANT

Requirement 4.6-2: COMPLIANT

Requirement 4.6-3: COMPLIANT

Requirement 4.6-4: COMPLIANT

Section 7: Assessment of Spacecraft Reentry Hazards
Detailed description of spacecraft components by size, mass, material, shape, and original
location on the space vehicle, if the atmospheric reentry option is selected: The AeroCube-7


                                        Page 13 of 15


AeroCube-7 / 5c ODAR                                                 The Aerospace Corporation


and AeroCube-5c vehicles are primarily constructed of aluminum and PCB electronic board
material. The only components with a higher density or resistance to melting are stainless steel
screws, ceramic path antennas, and three small stainless steel reaction wheels. The spacecraft
components used in the DAS 2.0.2 analysis are listed belowError! Reference source not
found.. The DAS analysis shows these materials pose no risk per the ODAR requirement.

Summary of objects expected to survive an uncontrolled reentry: The higher-risk materials
mentioned above have flown or will fly on several AeroCube missions, including AeroCube-4,
AeroCube-5, and AeroCube-6. A DAS 2.0.2 analysis shows these materials pose no risk per the
ODAR requirement.

Calculation of probability of human casualty for the expected year of uncontrolled reentry
and the spacecraft orbital inclination: Zero

Assessment of spacecraft compliance with Requirement 4.7-1:

Requirement 4.7-1: COMPLIANT

Section 8: Assessment for Tether Missions
The AeroCube-7 /5c mission has no tether. All requirements are COMPLIANT.

Sections 9–14: Assessment of Launch Vehicle Debris
AeroCube-7 /5c satellites will fly as a secondary payload. Assessment of launch-vehicle debris is
the responsibility of the primary payload. These sections are N/A for AeroCube-7 / 5c.




                                         Page 14 of 15


AeroCube-7 / 5c ODAR                                                                                     The Aerospace Corporation

                            Table 1. Spacecraft Components used for DAS 2.0.2 Analysis
Row Num    Name                                               Parent Qty Material              Body Type Thermal Mass Diameter/Width   Length   Height
       1   AC5C complete                                           0 1 Aluminum 6061-T6        Box                   2           0.1     0.15      0.1
       2   AC5C shell                                              0 1 Aluminum 6061-T6        Box               0.213           0.1     0.15      0.1
       3   Battery bracket 5C inside shell                         2 1 Aluminum 6061-T6        Box               0.012         0.026     0.09    0.013
       4   Reaction wheel block 5C inside shell                    2 1 Aluminum 6061-T6        Box               0.015         0.028    0.029    0.028
       5   Antenna 5C inside shell                                 2 1 Alumina                 Flat Plate        0.007          0.04     0.05
       6   Battery 5C inside shell                                 2 1 Stainless Steel 17-4 ph Cylinder          0.017         0.016    0.033
       7   AVO 5C inside shell                                     2 1 Stainless Steel 17-4 ph Cylinder          0.023         0.026     0.04
       8   Circuit Boards 5C inside                                2 1 Fiberglass              Flat Plate         0.03         0.056    0.056
       9   ADIS 5C inside shell                                    2 1 Aluminum 6061-T6        Box               0.049         0.044    0.047   0.014
      10   AC5C Lids inside shell                                  2 1 Aluminum 6061-T6        Flat Plate        0.086         0.096    0.105
      11   Payload interface plate 5C inside shell                 2 1 Aluminum 6061-T6        Flat Plate        0.092         0.097    0.097
      12   STIM 5C inside shell                                    2 1 Aluminum 6061-T6        Box                0.11         0.048    0.053   0.026
      13   Pea Placer 5C inside shell                              2 1 Aluminum 6061-T6        Cylinder          0.117         0.037    0.043
      14   EM Assembly 5C inside shell                             2 1 Fiberglass              Box               0.275         0.078    0.089   0.047
      15   Payload Assembly 5C inside shell                        2 1 Aluminum 6061-T6        Box               0.573         0.097    0.097   0.092
      16   Body Structure 5C inside shell                          2 1 Aluminum 6061-T6        Box               0.582         0.105    0.165   0.105
      17   pea 5C inside shell                                     2 10 Brass- Cartridge       Cylinder        0.0012          0.008    0.013
      18   Battery bracket 5C                                      0 1 Aluminum 6061-T6        Box               0.012         0.026     0.09   0.013
      19   Reaction wheel block 5C                                 0 1 Aluminum 6061-T6        Box               0.015         0.028    0.029   0.028
      20   Antenna 5C                                              0 1 Alumina                 Flat Plate        0.007          0.04     0.05
      21   Battery 5C                                              0 1 Stainless Steel 17-4 ph Cylinder          0.017         0.016    0.033
      22   AVO 5C                                                  0 1 Stainless Steel 17-4 ph Cylinder          0.023         0.026     0.04
      23   Circuit Boards 5C                                       0 1 Fiberglass              Cylinder           0.03         0.056    0.056
      24   ADIS 5C                                                 0 1 Aluminum 6061-T6        Box               0.049         0.044    0.047   0.014
      25   AC5C Lids                                               0 1 Aluminum 6061-T6        Flat Plate        0.086         0.096    0.105
      26   Payload interface plate 5C                              0 1 Aluminum 6061-T6        Flat Plate        0.092         0.097    0.097
      27   STIM 5C                                                 0 1 Aluminum 6061-T6        Box                0.11         0.048    0.053   0.026
      28   Pea Placer 5C                                           0 1 Aluminum 6061-T6        Cylinder          0.117         0.037    0.043
      29   EM Assembly 5C                                          0 1 Fiberglass              Box               0.275         0.078    0.089   0.047
      30   Payload Assembly 5C                                     0 1 Aluminum 6061-T6        Box               0.573         0.097    0.097   0.092
      31   Body Structure 5C                                       0 1 Aluminum 6061-T6        Box               0.582         0.105    0.165   0.105
      32   AeroCube7 Complete                                      0 1 Aluminum 6061-T6        Box                 2.2           0.1     0.15     0.1
      33   AeroCube7 shell                                         0 1 Aluminum 6061-T6        Box               0.213           0.1     0.15     0.1
      34   Wing Assembly AC7 inside shell                         33 2 Aluminum 6061-T6        Box               0.055         0.079     0.15   0.025
      35   Anti-Nadir Lid Assembly AC7 inside shell               33 1 Aluminum 6061-T6        Box             0.0583          0.103    0.108   0.002
      36   Camera Lens (Xenoplan/Schneider) AC7 inside shell      33 1 Aluminum 7075-T6        Cylinder        0.0872          0.032    0.039
      37   Rate Gyro Assembly AC7 inside shell                    33 1 Aluminum 6061-T6        Box               0.095         0.048     0.06   0.025
      38   Nadir Lid Assembly AC7 inside shell                    33 1 Aluminum 6061-T6        Flat Plate        0.187         0.102    0.108
      39   Laser Comm Plate AC7 inside shell                      33 1 Aluminum 6061-T6        Box             0.2207          0.102    0.103   0.019
      40   Laser Isolator AC7 inside shell                        33 1 HyMu80                  Cylinder          0.227         0.027    0.072
      41   Body Assembly AC7 inside shell                         33 1 Aluminum 6061-T6        Box                0.45         0.113     0.16   0.106
      42   Electronics module with batteries AC7 inside shell     33 1 Fiberglass              Box               0.514          0.08     0.08    0.07
      43   Wing Assembly AC7                                       0 1 Aluminum 6061-T6        Box               0.055         0.079     0.15   0.025
      44   Anti-Nadir Lid Assembly AC7                             0 1 Aluminum 6061-T6        Box             0.0583          0.103    0.108   0.002
      45   Camera Lens (Xenoplan/Schneider) AC7                    0 1 Aluminum 7075-T6        Cylinder        0.0872          0.032    0.039
      46   Rate Gyro Assembly AC7                                  0 1 Aluminum 6061-T6        Box               0.095         0.048     0.06   0.025
      47   Nadir Lid Assembly AC7                                  0 1 Aluminum 6061-T6        Flat Plate        0.187         0.102    0.108
      48   Laser Comm Plate AC7                                    0 1 Aluminum 6061-T6        Box             0.2207          0.102    0.103   0.019
      49   Laser Isolator AC7                                      0 1 HyMu80                  Cylinder          0.227         0.027    0.072
      50   Body Assembly AC7                                       0 1 Aluminum 6061-T6        Box                0.45         0.113     0.16   0.106
      51   Electronics module with batteries AC7                   0 1 Fiberglass              Box               0.514          0.08     0.08    0.07
      52   pea 5C                                                  0 10 Brass- Cartridge       Cylinder        0.0012          0.008    0.013




                                                               Page 15 of 15



Document Created: 2015-07-09 10:14:33
Document Modified: 2015-07-09 10:14:33

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