Safety Assessment for secondary payloads launched by Japanese Expendable Launch Vehicle 6th 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 sub- satellites 4. Improvement of safety requirement and safety review process 5. Summary
2 Launch sites for ELV in Japan
Tanegashima Space Center (TNSC)
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 ・PAF for small sub-satellites is (1) Payload Attach Fitting attached to PSS ・PAF has a capability to attach less than 50 cm-cubic and less than 50 fairing kg satellites small sub- PAF for small satellite sub-satellite
main satellite
Payload Support Payload Attach Structure (PSS) Fitting (PAF) for main satellite 6 How to load small sub-satellites (2) JAXA Pico satellite deployer (J-POD)
small sub- satellite
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
7 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 sub- satellites 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 (2) Damage or loss of (3) space debris generation operator / launch site launch vehicle or main satellite
Typicaly, no ground operation is required “Damage or loss of main for small sub-satellites satellite” is a unique identified hazard bacause small sub-satellites are mounted near a main satellite 9 Safety requirements for ELV payloads
JERG-1-007 on-orbit operation Safety Regulation for Launch Site JMR-002 Operation/Flight Control Operation Launch Vehicle Payload Safety Standard section 5 launch site operation @TNSC, USC disposal design/manufacture/test
JMR-003 Space Debris Mitigation Standard safety design
Pressure systems
JERG-0-001 10 launch TechnicalThese Standard safety for High requirements are applied to not only Pressure Gas Equipment Formain Space Use satellites but also small sub-satellites.JMR-001 Life cycle of an ELV payload System Safety Standard JMR-002 system safety management Launch Vehicle Payload Safety 10 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 sub- satellites 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 RF - Powered off during launch and launch site transmitter operation
Electrical Solar Array circuits Paddle (SAP)
12 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. 3 inhibits are required for inadvertent RF radiation, inadvent deployment of mechanism Hazardous function battery (Mech, RF) inhibit
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 Typical small sub-satellites for J-POD 13 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. Some of sub-satellite organizations are not familiar Internal short: with these assessment.
- Charge/discharge test before/after environmental test JAXA created “guideline for safety assessment of External short: COTS LIB” - 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 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 Nichrome wire cuts Lock wire Non-metal lock wire lock wire by its heat
- Redundant lock wires for fail-safe design Antenna Electrical inhibit 1 - Tension strength - Creep deformation Electrical inhibit 2 - Integrity of knot Electrical - Management of inhibit 3 tension
JAXA created “guideline Battery 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 sub- satellites 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 were created Standard hazard reports • Ignition in Explosive hazardous atmosphere • Electromagnetic compatibility • Electrical Shock • 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”.
Interpretation / Guidelines Inhibit monitoring Hazard severity of RF radiation to human body Explosion proof design Safety critical mechanisms lockStandard wire of deployment hazard mechanismreports, Interperation / guidelines COTSare helpful lithium ion to battery small sub-satellites organization 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.
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21 Framework of safety requirements for ELV payloads
JAXA has two kinds of requirements; JAXA’s Management Requirement JAXA’s Engineering Regulation (JMR): (JERG): specifies and standardizes the specifies the technical requirements, requirements for management of guidelines, standards, technical reliability, quality, safety, information, interpretation for system configuration and so on. design.
Main safety requirements applied to ELV payloads JMR-001 System Safety Standard JMR-002 Launch Vehicle Payload Safety Standard TheseJMR-003 safety Space Debris requirements Mitigation Standard are applied to not only JERG-0-001 Technical Standard for High Pressure Gas Equipment For Space Use mainJERG -1satellites-007 Safety Regulation but foralso Launch small Site Operation/Flight sub-satellites. Control Operation
22 Typical process of JAXA SSRP
Safety Review Safety Review Safety Review Safety Review Phase 0 Phase I Phase II Phase III (Design Concept) (PDR) (CDR) (Delivery)
・Confirmation of ・ Confirmation of ・Confirmation of identified hazards and implement controls identified hazards ・Confirmation of hazard controls for design and hazard causes complete ・Confirmation of ・Confirmation of ・Confirmation of verification preliminary detailed verification safety requirement verifications methods
JAXA typically conducts four-time safety review panels according to each development phase Safety Verification JAXA SSRP requires safety data package including hazard reports at Tracking Log each phase. 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 The Japanese law does not have the regulation specialized in high pressure gas equipments for space use, therefore JAXA creates and requires... JERG-0-001 “Technical Standard for high pressure gas equipment for space use” 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
antenna
hold and release mechanism Fault tolerant for the If inadvetent antenna deployment leads to loss mechanism shall be applied. or damage of vehicle during ascent ... 25 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”.
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