Safety Assessment for secondary payloads launched by Japanese Expendable Launch Vehicle

Safety Assessment for secondary payloads launched by Japanese Expendable Launch Vehicle 6 th IAASS(International Association for the Advancement of Space Safety) Safety is Not an Option Montreal, Canada May 22, 2013 Masami Miki (Japan Manned Space Systems Corporation (JAMSS)) Ryoji Kobayashi, Manami Nogami, Yasuhiro Kawada, Nobuo Takeuchi (Japan Aerospace Exploration Agency (JAXA)) 1

Contents 1. Introduction 2. Overview of JAXA SSRP 1. Scope of the safety review for small-sub satellites 2. Framework of safety requirements for ELV payload 3. Typical Design and related hazards of small subsatellites 4. Improvement of safety requirement and safety review process 5. Summary 2

Tanegashima Space Center (TNSC) Launch sites for ELV in Japan Epsilon rocket which have Solid propellant booster rockets developed mainly for space scientific observations and space engineering experiments are launched from USC. Uchinoura Space Center (USC) H-IIA, or H-II B which have Liquid Rocket propulsion and Solid Strap-on Boosters are launched from TNSC. 3

ELVs and ELV paylaods in Japan International Space Station (ISS) Major Specifications of the H-IIA launch vehicle Length (m) : 53 Liftoff mass (t) : 285 (without payload mass) Guidance Method: Inertial Guidance Method H-II A launch Vehicle H-IIA/H-IIB have the ability to launch such as Earth Observation Satellites Communication, Positioning and Engineering Test Satellites Astronomical Observation Satellites Lunar and Planetary Exploration Spacecraft HTV (H-II Transfer Vehicle ) 4

Capability of launch for small sub-satellites JAXA recently provides a launch and operation opportunity for small sub-satellites by utilizing the excessive capability of H-IIA. Akatsuki (Planet-C) 14 small sub-satellites have been successfully launched so far 11 small sub-satellites will be launched near future Example of Launch configuration 5

How to load small sub-satellites (1) Payload Attach Fitting fairing small subsatellite PAF for small sub-satellites is attached to PSS PAF has a capability to attach less than 50 cm-cubic and less than 50 kg satellites PAF for small sub-satellite main satellite 6 Payload Support Structure (PSS) Payload Attach Fitting (PAF) for main satellite

How to load small sub-satellites (2) JAXA Pico satellite deployer (J-POD) small subsatellite 7 Deployment configuration of J-POD J-POD is attached to PSS J-POD has a capability to hold 4 satellites which are less than 20 cm-cubic

Contents 1. Introduction 2. Overview of JAXA SSRP 1. Scope of the safety review for small-sub satellites 2. Framework of safety requirements for ELV payload 3. Typical Design and related hazards of small subsatellites 4. Improvement of safety requirement and safety review process 5. Summary 8

JAXA System Safety Review Panel (SSRP) and its Scope During launch site operation or launch, there potentially exist some hazards due to failure of small sub-satellites toward third-party, launch vehicle, main satellites or JAXA personnel and so on. JAXA confirms adequate mitigation of the risk due to failure of small sub-satellites at JAXA System Safety Review Panel (SSRP) Scope of JAXA SSRP (1) Damage or loss of ground operator / launch site (2) Damage or loss of launch vehicle or main satellite (3) space debris generation Typicaly, no ground operation is required for small sub-satellites Damage or loss of main satellite is a unique identified hazard bacause small sub-satellites are mounted near a main satellite 9

Safety requirements for ELV payloads JMR-002 Launch Vehicle Payload Safety Standard section 5 design/manufacture/test JERG-1-007 Safety Regulation for Launch Site Operation/Flight Control Operation launch site operation @TNSC, USC on-orbit operation disposal safety design JMR-003 Space Debris Mitigation Standard Pressure systems 10 JERG-0-001 Technical These Standard safety for High requirements are applied launch to not only Pressure Gas Equipment For Space Use JMR-001 main satellites but also small sub-satellites. System Safety Standard Life cycle of an ELV payload system safety management 10 JMR-002 Launch Vehicle Payload Safety Standard

Contents 1. Introduction 2. Overview of JAXA SSRP 1. Scope of the safety review for small-sub satellites 2. Framework of safety requirements for ELV payload 3. Typical Design and related hazards of small subsatellites 4. Improvement of safety requirement and safety review process 5. Summary 11

Typical designs of small sub-satellites - No launch site operation execept for detaching non-flight items - Powered off during launch and launch site operation RF transmitter <Hazard> Inadvertent RF radiation Small sub-satellites launched with NASA GPM satellites <Hazard> Ignition at explosive atmosphere <Hazard> Rupture or explosion of batteries Electrical circuits Secondary batteries 12 Solar Array Paddle (SAP) Some of potential hazardous sources are considered to be small, however, JAXA SSRP review these hazards based on worst case assumption. <Hazard> Inadvertent deploy of depolyment mechanism Antenna

Electrical inhibits Electrical failure is one of the hazard causes of inadvertent deployment or inadvertent RF radiation and so on. Typical small sub-satellites have electrical inhibits against these hazard causes. Hazardous function (Mech, RF) inhibit 3 inhibits are required for inadvertent RF radiation, inadvent deployment of mechanism battery Typical electrical circuit No chattering during shock/vibration test is confirmed (No ignition source at explosive atmoshere) Mechanical micro switch used for small sub-satellites 13 Typical small sub-satellites for J-POD

COTS Secondary batteries Commercial off the shelf (COTS) secondary batteries such as Lithium ion battery (LIB) or Nickel metal hydride battery are used. Especially, the following items are verified for LIBs. Internal short: - Charge/discharge test before/after environmental test External short: - Two protection devices against external short such as PTC, fuse, separator shutdown etc - Insulation design of battery itself and downstream circuit of battery Overcharging: - two fault tolerant protection devices 14 Some of sub-satellite organizations are not familiar with these assessment. JAXA created guideline for safety assessment of COTS LIB

Hold & Release mechanism for SAP/Antenna Mechanical failure is one of the hazard causes of inadvertent deployment. Typical small sub-satellites use non-metal lock wire for hold & release mechanism. Nichrome wire cuts lock wire by its heat Nichrome wire Lock wire Non-metal lock wire Antenna Electrical inhibit 1 Electrical inhibit 2 Electrical inhibit 3 - Redundant lock wires for fail-safe design - Tension strength - Creep deformation - Integrity of knot - Management of tension Battery JAXA created guideline for non-metal lock wire 15

Contents 1. Introduction 2. Overview of JAXA SSRP 1. Scope of the safety review for small-sub satellites 2. Framework of safety requirements for ELV payload 3. Typical Design and related hazards of small subsatellites 4. Improvement of safety requirement and safety review process 5. Summary 16

Improvement of Safety requirement and safety review process Several issues were identified during safety assessments for small sub-satellites. The features of small sub-satellites are; Potential hazardous sources of small sub-satellites are generally small Some of small sub-satellites organization are not familiar with safety assessment. Improvement of safety assessment tools 17

Standard Hazard Reports JAXA SSRP previously required to submit the full hazard reports even if the identified hazard and hazard control were general and common among each payload. Standard hazard reports Ignition in Explosive hazardous atmosphere Electromagnetic compatibility Electrical Shock Standard hazard reports were created COTS Battery rupture, electrolyte leakage Sharp edge, corner, protrusion 18

Interpretation / Guidelines Interpretation documents of safety requirements were prepared because the requirements are conservative or ambiguous description in JMR-002 Launch Vehicle Payload Safety Standard. Inhibit monitoring Interpretation / Guidelines Hazard severity of RF radiation to human body Explosion proof design Safety critical mechanisms Standard hazard reports, Interperation / guidelines are helpful to small sub-satellites organization lock wire of deployment mechanism COTS lithium ion battery Use of materials sensitive to Stress Corrosion Cracking (SCC) 19

Summary JAXA has been assuring the safety of third-party, H- IIA rocket, main satellites, or ground operators through the system safety activity by small sub-satellite organizations and through the review by JAXA SSRP, and there is no mishaps so far. JAXA SSRP will continue this safety review and promote safety activity. Also, JAXA SSRP will improve its requirements and process so that more efficient and effective safety review can be performed. 20

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Framework of safety requirements for ELV payloads JAXA has two kinds of requirements; JAXA s Management Requirement (JMR): specifies and standardizes the requirements for management of reliability, quality, safety, configuration and so on. JAXA s Engineering Regulation (JERG): specifies the technical requirements, guidelines, standards, technical information, interpretation for system design. Main safety requirements applied to ELV payloads JMR-001 System Safety Standard JMR-002 Launch Vehicle Payload Safety Standard JMR-003 Space Debris Mitigation Standard These safety requirements are applied to not only JERG-0-001 Technical Standard for High Pressure Gas Equipment For Space Use main satellites but also small sub-satellites. JERG-1-007 Safety Regulation for Launch Site Operation/Flight Control Operation 22

Typical process of JAXA SSRP Safety Review Phase 0 Safety Review Phase I Safety Review Phase II Safety Review Phase III (Design Concept) (PDR) (CDR) (Delivery) Confirmation of identified hazards and hazard causes Confirmation of safety requirement Confirmation of identified hazards and hazard controls Confirmation of preliminary verifications Confirmation of implement controls for design Confirmation of detailed verification methods Confirmation of complete verification JAXA typically conducts four-time safety review panels according to each development phase JAXA SSRP requires safety data package including hazard reports at each phase. Safety Verification Tracking Log Phased safety analysis makes it possible to feed-back to payload design because safety analysis is performed in parallel with designing. -It is easier (less expensive) to change documentation than to change hardware 23

Unique points of discussion and review at JAXA SSRP (1) High pressure gas equipment for space use When the high pressure gas equipments are used in Japan, Especially when high pressure equipments are loaded of contents such as propellant in Japan, required... The review of compliance with the Japanese law The special permission of government JERG-0-001 Technical Standard for high pressure gas equipment for space use The Japanese law does not have the regulation specialized in high pressure gas equipments for space use, therefore JAXA creates and requires... If JAXA SSRP can approve the compliance with JERG-0-001 and reports the result of the review to government, review by government is exempted from. JAXA SSRP can make the review process more efficient 24

Unique points of discussion and review at JAXA SSRP (2) Hazards due to failure of payloads during ascent JAXA SSRP considers the following as catastrophic hazard; (1) Loss or damage of vehicle due to failure of payload during ascent (2) Loss or damage of adjacent major payload due to failure of payload during dual launch <Example> prior to antenna deployment after antenna deployment From safety perspective... antenna hold and release mechanism If inadvetent antenna deployment leads to loss or damage of vehicle during ascent... 25 Fault tolerant for the mechanism shall be applied.

Improvement of Safety requirement and safety review process Hazard severity of RF radiation toward human body During launch site operation, RF radiation hazard toward human body is identified, and the adequate inhibits are required according to the hazard. However, the criteria of these hazard severity were ambiguous in JMR-002. The interpretation letter was made based on Japanese law Guideline for protection of RF radiation. hazard severity criteria <table1: criteria for hazard severity of RF radiation> Marginal hazard Critical hazard Catastrophic hazard RF frequency < 3GHz When personnel cannot access within 10 cm from RF radiation source; Power of RF < 20 W When personnel can access within 10 cm from RF radiation source; Power of RF < 200 mw 20 W or 200 mw < Power of RF < 200 W Power of RF > 200 W 26