Payload Safety Review Plan and Issues Leland D. Hill

Payload Safety Review Plan and Issues

Leland D. Hill

July 15, 2004 Leland D. Hill 2

Phase II Flight Safety Review• Phase II (ФII) Safety Review

• Most critical safety review, where:• Final design is reviewed by the Payload Safety

Review Panel (PSRP) for compliance with Safety Requirements.

• Verification methods for assuring design safety compliance are agreed upon.

• ФIII Safety Review:• Final safety review, is primarily for addressing

completion of safety verification activities.


Scheduling ФII Safety Review• Current discussion is for a December 2004 ФII

Safety Review.• Meeting times very limited in December due to

holidays• 45 day submittal requirements will mandate

completion of the ФII Safety Data Package (SDP) for Mid October 2004.

• Recommend planning on a January 2005 ФII Meeting Date with a Mid November Delivery Date to Payload Safety Review Panel.


Status Of AMS-02 ФII SDP• Initial Draft of ФII SDP was reviewed within

LMSO in March, updates were indicated to comply with NSTS/ISS 13830, “Payload Safety Review and Data Submittal Requirements,” taking the ФI content to a ФII level.

• Responsibilities for updating text of the SDP assigned by LM Project Manager.

• LM Project Personnel have dedicated little time to SDP generation since early May due to the rebaselining effort


Safety Analysis – Hazard Reports• Original ФI/Draft ФII SDP contained 10 HRs

STD-AMS-02-1 Flight Payload Standardized Hazard Control Report – AMS-02 AMS-02-1 Structural Failure of Hardware (not pressure related pressure system

or sealed/vented container failures) AMS-02-2 Materials Offgassing AMS-02-3 Rupture of Vacuum Case and/or SFHe Tank/Lines/Fittings/

Pressurized Components AMS-02-4 Venting of Helium Gas AMS-02-5 Rupture of the Following AMS-02 Pressure Systems:

TRD Xe & CO2 Gas Supplies (See attached schematics), Warm He Supply or Thermal Control System (TCS) (See attached schematics).

AMS-02-6 Venting of Xenon (Xe) or Carbon Dioxide (CO2) Gas from the TRD; Venting from the Warm Helium Supply System and/or Venting of CO2 or ammonia from the Thermal Control System (TCS).

AMS-02-7 Electromagnetic Interference (EMI) from AMS-02 Magnetic Field AMS-02-8 Electrical Shock AMS-02-9 Excessive Ionizing Radiation


Safety Analysis – Hazard Reports• Revised updated safety analysis led to

hazard report reorganization and additional hazard reports being prepared.

• Hazard reports were reassigned hazard identifiers (numbers) in this reorganization.


Safety Analysis – Hazard Reports• Revised ФII SDP contains 20 Hazard Reports

HR Hazard Report Title STD-AMS-02-F01 Flight Payload Standard Hazard Report – Exterior Elements STD-AMS-02-F02 Flight Payload Standard Hazard Report – Interior Elements AMS-02-F01 Structural Failure of Hardware AMS-02-F02 Toxic Material Offgassing

AMS-02-F03 Rupture of Superfluid Helium Tank, Vacuum Case and/or Pressurized System

AMS-02-F04 Overpressurization of Payload Bay Doors

AMS-02-F05 Rupture of AMS-02 Pressurized Systems: TRD Gas System (Xe & CO2), Cryomagnet Warm He System, Thermal Control System

AMS-02-F06 Excessive Thrust/Overturning Moments AMS-02-F07 Excessive Radiated Field Strengths, EMI, Magnetic AMS-02-F08 Electric Shock/Discharge AMS-02-F09 Exposure of the Crew to Excessive Ionizing Radiation AMS-02-F10 Flammable Materials in the Payload Bay AMS-02-F11 Mechanism Failure AMS-02-F12 Mate/Demate of Connectors AMS-02-F13 Battery Failure AMS-02-F14 EVA Operations Hazard AMS-02-F15 Thermal Extremes AMS-02-F16 Shatterable Material Release AMS-02-F17 Electrical Power Distribution Damage AMS-02-F18 Rapid Safing/Payload Reconfiguration

Reorganized New


SDP Status• Hazard Reports

• All hazard reports to be reformatted for ФII• Eleven (11) hazard reports have been drafted.

• Need additional coordination or supporting data.

• Eight (8) hazard reports have yet to be revised/drafted.

• Verifications will need to be coordinated across all applicable parties.


SDP – Issues• Current issues relate principally to

documentation and coordination of information, not design deficiencies.


SDP – Issues• AMS-02 is a pathfinder in the safety

process for attached exterior payloads on the ISS. There are accepted standards within the payload safety process, based on Shuttle interior and payload bay payloads and ISS rack based payloads, that may not be applicable for payloads mounted on the ISS truss.


SDP – Issues• Coronal Discharge

• AMS-02 utilizes high voltages and will generate its own rarified atmosphere during operations.

• Coronal Discharge unlikely to affect ISS, AMS-02 systems only, so hazard potential is very low.

• Need to establish high voltage protections are adequate for this environment, additional data will be requested from suppliers of high voltage sources.


SDP – Issues• Warm Helium Gas Supply

• System is still in flux, possible replacement with entirely different system

• Venting• No descriptions available for non-propulsive

vents and vent locations


SDP – Issues• Mate/Demate of Connectors

• AMS-02 does not have a means of inhibiting power usage or minimizing downstream power loads.

• Not clear that vehicles can provide needed two inhibits for EVA mate/demate of connectors.

• AMS-02 EVA Cables can be protected by remotely controlled UMA disconnect (1) and ISS power removal (2).

• Nominal robot connection have EVA backup mate/demate that must meet requirements.

• Have to rely entirely on vehicle power inhibits.


SDP Supporting Documents

• Fracture Control Status.• Significant data has been received, Status Summary

needs to be written.

• Thermal Design.• Design still not complete and documented.

• Delta CDR for Thermal Systems should resolve this issue

• Structural Verification Plan• Needs additional revision based on updated information


SDP Supporting Documents

• Battery Verification Plan• Complete

• Material Usage Agreements• Being Prepared, additional MUAs will be

prepared as materials are identified.


Outstanding Requests• Pressurized Systems

• Pressure systems tables• Cryomagnet


Outstanding Requests• Avionics

• High Voltage and Bonding/Grounding Data• ECAL

• TOF

• TRD

• Tracker

• Tracker Thermal

• TRD Gas

• ACC

• Nominal power on pad before L-30

• Grounding concepts for the TCS


Outstanding Requests• Thermal

• Pad Operations Thermal environment and purge requirements

• Thermal constraints to pad operations

• Update of temperature result table for nominal ISS operations (Partial information received)

• Launch to activation analysis (Data received, under review)

• Ramp up analysis

• Loss of Power analysis(Data received, under review)

• Transfer operations analysis(Data received, under review)

• Pictures/drawings/sketches of heater locations and information (Partial information received)

• MLI drawings/sketches/pictures for all applications