EUROPA-PROP-SPEC-0008_RevA_FINAL_(002).pdf

Effective Date: 01/30/2018

Expiration Date: 01/30/2023

Check https://ipdtdms.gsfc.nasa.gov to verify that this is the correct version prior to use

400-FORM-0002 (4/16/2014)

EUROPA-PROP-SPEC-0008, Revision A

EUROPA Clipper Propulsion, Code 597

Europa Project

Pressurant Tank Specification

Goddard Space Flight Center

Greenbelt, Maryland

National Aeronautics and

Space Administration

GSFC EUROPA Clipper Propulsion

CMO K. Mrowczynski

01/30/2018

RELEASED

https://ipdtdms.gsfc.nasa.gov/

Pressurant Tank Specification EUROPA-PROP-SPEC-0008, Revision A ii

Pressurant Tank Specification

Signature/Approval Page

Prepared by:

Eric Cardiff

Reviewers/Approvers:

Liz Citrin

Daniel Ramspacher

Eric Cardiff

Matthew Fox

Approved by:

Liz Citrin

*** Electronic signatures are available on-line at: https://ipdtdms.gsfc.nasa.gov*** https://ipdtdms.gsfc.nasa.gov/ iii

Preface

This document is a Europa Clipper Propulsion signature-controlled document. Changes to this document require prior approval of the applicable Product Design Lead (PDL) or designee. Proposed changes shall be submitted in the Technical Data Management System

(TDMS) via a Signature Control Request (SCoRe) along with supportive material justifying the proposed change. Changes to this document will be made by complete revision.

All of the requirements in this document assume the use of the word "shall" unless otherwise stated.

Questions or comments concerning this document should be addressed to:

Europa Configuration Management Office

Mail Stop: 597

Goddard Space Flight Center

Greenbelt, Maryland 20771 iv

Change History Log

Revision Effective Date Description of Changes

(Reference the SCoRe Approval Date)

Revision - 12/04/2017 Released following approval of EUROPA-SCoRe-0067

Revision A 01/30/2018 Released following approval of EUROPA-SCoRe-0103 v

Table of Contents

1.0 Introduction

1.1 General Information

1.2 Scope

1.3 Pressurant Tank Definition and Description

2.0 Applicable Documents

3.0 Functional/Performance Requirements

3.1 COPV Flight Unit Functional/Performance Requirements

3.1.1 Pressure

3.1.2 External Leakage

3.1.3 Pressure Cycle Life

3.2 Electrical Grounding

3.3 Radiation

4.0 Physical Requirements

4.1 Volume

4.2 Mass Properties

4.3 Physical Envelope

4.4 Mounting

4.5 Fluid Interface tube

4.5.1 Dimensions

4.5.2 Location

4.5.3 Material

5.0 Environmental Requirements

5.1 Handling Environments

5.2 Quasi-Static Acceleration

5.3 Frequency Requirement

5.3.1 Fundamental Frequencies

5.4 Vibration

5.4.1 Sinusoidal Vibration

5.4.2 Random Vibration

5.5 Shock

5.6 External Pressure

5.7 Humidity

5.8 Thermal Requirements

6.0 Cleanliness

6.1 Surface Contamination & Planetary Protection

6.1.1 Surface Contamination Levels at Delivery

6.1.2 Material Selection

7.0 Design & Construction requirements

7.1 Identification and Marking

7.2 Interchangeability

7.3 Lifetime

Appendix A Abbreviations and Acronyms (TBR) vi

List of Tables Table Page

Table 1: Applicable Documents Table 2: Pressure Cycle Requirements

Table 3: Handling Environments Table 4: Sine Vibration Environment Table 5: Random Vibration Levels Table 6: Shock Levels Table 7: Temperature Levels

List of Figures

Figure Page

Figure 1 COPV Physical Envelope

1.0 INTRODUCTION

1.1 GENERAL INFORMATION

The Europa mission is being formulated and implemented by a joint partnership between the Jet Propulsion Laboratory and the Applied Physics Laboratory, with NASA GSFC building the propulsion system for the Applied Physics Laboratory.

1.2 SCOPE

This specification describes the mechanical requirements as well as the environmental verification testing requirements for a space-qualified Pressurant Tank for the Europa mission.

1.3 PRESSURANT TANK DEFINITION AND DESCRIPTION

The Europa Propulsion Subsystem design employs two (2) identical pressurant tanks hereafter referred to as Composite Overwrapped Pressure Vessels (COPVs) to store high-pressure helium. The term COPV includes a metal liner, composite overwrapping, two polar mounting bosses, and a single port used to fill and vent the vessel.

2.0 APPLICABLE DOCUMENTS

The following documents and drawings in effect on the day this specification was signed shall apply to the fabrication and to the mechanical, and environmental requirements of the COPV to the extent specified herein. In the event of conflict between this specification and any referenced document, this specification will govern, with the exception of the COPV Statement of Work (GSFC-EUROPA-SOW-0008), in which case the Statement of Work (SOW) takes precedence.

Table 1 is a list of the applicable specifications and publications.

Table 1: Applicable Documents

Document Number Title Revision/Date

EUROPAPROP-

SOW-0008

COPV SOW TBD

ANSI/AIAA S-081-

Space Systems – Composite

Overwrapped Pressure Vessels

(COPVs)

ANSI/AIAA S-080-

Space Systems – Metallic Pressure

Vessels, Pressurized Structures, and

Pressure Components.

NASA-STD-8719.24 NASA EXPENDABLE LAUNCH

VEHICLE PAYLOAD SAFETY

REQUIREMENTS

9/30/2015

IEST-STD-CC1246E Product Cleanliness Levels And

Contamination Control Program

MIL-PRF-27407B Propellant, Helium, Pressurizing Agent 08/25/1997

MIL-PRF-27401D Propellant, Nitrogen, Pressurizing Agent 10/03/1995

MIL-PRF-27415A Propellant Pressurization Agent, Argon 12/11/1997

MIL-PRF-26539E Propellant, Nitrogen Tetroxide

(MON-3, Low Iron)

10/07/1997

MIL-PRF-27404C Propellant, Monomethylhydrazine 10/01/1997

TT-I-735 Isopropyl Alcohol 07/11/1963

JSC-SPEC-C-20C Water, High Purity, Specification for 06/14/1976

MIL-HDBK-17 Polymer Matrix Composites, Three

Volumes

01/23/1997

MIL-STD-453C Inspection, Radiographic 12/27/1984

GSFC-S-313-009 Fluorescent Penetrant Test Method

Requirements and Guidelines

MIL-STD-1540D Test Requirements for Space Vehicles 07/01/1985

ANSI/NCSL Z540.1 Calibration Laboratories & Measuring &

Test Equipment

GSFC-X-673-64-lF Engineering Drawing Standards Manual 09/1994

ASTM E-595-07 Standard Test Method for Total Mass

Loss and Collected Volatile

Condensable Materials from Outgassing in a Vacuum Environment

12/01/2007

MIL-C-5541 Military Specification, Chemical

Conversion Coatings on Aluminum and

Aluminum Alloys

SAE-AMS-2244C Tolerances (R) Titanium and Titanium

Alloy Tubing

AMS 2488 Anodic Treatment - Titanium and

Titanium Alloys Solution Ph 13 Or Higher

06/01/2000

EEE-INST-002 Instructions for EEE Parts Selection, Screening, Qualification, and Derating

04/2008

EUROPA-PROP-

SPEC-0001

Subsystem Specification

3.0 FUNCTIONAL/PERFORMANCE REQUIREMENTS

The component shall be designed to withstand the operational and non-operational environments specified in the following section without degradation to mission goals and performance requirements.

3.1 COPV FLIGHT UNIT FUNCTIONAL/PERFORMANCE REQUIREMENTS

3.1.1 Pressure

Operating Pressure

The COPV shall have a Maximum Expected Operating Pressure (MEOP) of no less than 4500 psia at a temperature of 40°C when loaded with gaseous helium pressurant.

Rationale: Derived from the Europa Propulsion Subsystem Spec, EUROPA-PROP-

SPEC-0001.

Proof Pressure

The COPV shall be capable of withstanding a proof pressure of 5625 psig without any permanent physical deformation, yielding, or cracking.

Rationale: MEOP x 1.25; refer to NASA-STD-8719.24.

Burst Pressure

The COPV shall demonstrate, through a qualification program, a burst pressure of no less than 6750 psig.

Rationale: MEOP×1.5; refer to NASA-STD-8719.24.

Interface Tube Design Proof Pressure

The COPV interface tube shall be capable of withstanding a proof pressure of no less than 6750 psig without any permanent deformation, yielding, or cracking.

Rationale: MEOP × 1.5 for lines and fittings with diameter less than 1.5 in; refer to AIAA S-080.

Interface Tube Design Burst Pressure

The vendor shall demonstrate through a qualification program or by similarity, that the interface tube has a design burst pressure of no less than 18,000 psig.

Rationale: MEOP × 4 for lines and fittings with diameter less than 1.5 in; refer to

NASA-STD-8719.24.

3.1.2 External Leakage

The COPV shall demonstrate a total leak rate of no greater than 1×10-6 sccs of gaseous helium at MEOP.

Rationale: Required level maintains system performance throughout the mission per Leakage Analysis, TBD.

3.1.3 Pressure Cycle Life

At a minimum, the COPV shall be designed to operate without degradation in performance after enduring the pressure cycles listed in Table 2.

Table 2: Pressure Cycle Requirements

Pressure Load Type

Low Pressure Limit (psig)

High Pressure Limit (psia)

Number of Cycles

Proof Pressure 0 Proof per 3.1.1.2 5

MEOP 0 MEOP per 3.1.1.1 10

⅛ MEOP 0 1/8 * MEOP Unlimited

Rationale: Compliance with NASA-STD-8719.24.

3.2 ELECTRICAL GROUNDING

The DC resistance of a mechanical contact from one boss of the tank to the other shall be less than or equal to 1 milliohm DC resistance.

Rationale: 1.0 mΩ is an allocation to meet the component to chassis requirement of the

EIG (D56068) RQ103.521.

3.3 RADIATION

The COPV shall be compatible with a radiation exposure of 20 Mrad (this includes an RDF of

2.0).

Rationale: Ray trace analysis predicts 10 Mrads exposure.

4.0 PHYSICAL REQUIREMENTS

4.1 VOLUME

The COPV shall have a minimum pressurant volume of 97 Liters at MEOP.

Rationale: Derived from the Europa Propulsion Subsystem Spec, EUROPA-PROP-

SPEC-0001.

4.2 MASS PROPERTIES

The COPV shall have a mass of less than or equal to 18.4 kg.

Rationale: Derived from the Europa Propulsion Subsystem Spec, EUROPA-PROP-

SPEC-0001.

4.3 PHYSICAL ENVELOPE

The COPV shall be cylindrical with rounded ends. The COPV shall have an outer diameter of less than 16.8 inches (50.8 cm) at MEOP. The length of the tank shall be less than 34.6 inches (13.6 cm) at MEOP. See Figure 1.

Figure 1 COPV Physical Envelope

Rationale: Design.

4.4 MOUNTING

The COPV shall have a bolted interface (fluid interface tube) at one end and a spherical bearing at the other end. Each mount shall be located on the COPV’s center axis. The interfaces shall be sized to support the loads of the COPV, fully pressurized to MEOP, under all environmental conditions specified herein.

Rationale: Brackets and fasteners are the primary method for mounting the COPV.

4.5 FLUID INTERFACE TUBE

4.5.1 Dimensions

The COPV shall have a single interface tube with an outer diameter of

0.25 (+0.004/-0.000) inches, tube wall thickness of 0.035 ±0.002 inches, and length no less than 3.32 inches.

Rationale: Tolerances Given per SAE-AMS-2244C.

4.5.2 Location

The interface tube shall be concentrically aligned with the COPV’s central axis and at the hard-mount interface.

4.5.3 Material

The material at the tube interface shall be 6Al-4V Titanium. The interface tube may contain a material transition from the tank liner to titanium. If a material transition is used, the interface transition shall be 6Al4V Titanium.

Rationale: Derived from the Europa Propulsion Subsystem Spec, EUROPA-PROP-

SPEC-0001.

5.0 ENVIRONMENTAL REQUIREMENTS

Environmental design requirements for the COPV are specified in this section. The COPV shall be capable of meeting all performance requirements after exposure to the environments specified in this section.

5.1 HANDLING ENVIRONMENTS

The COPV shall be designed to survive without degradation the thermal, pressure and relative humidity environments specified below in Table 3.

Table 3: Handling Environments

Control Parameter Low Limit High Limit

Air Temperature (Storage)

Air Temperature (Operational)

Temperature Change Rate

Pressure (10,000 ft max. altitude)

Relative Humidity

+5°C

+5°C

-10°C/hr (TBR)

6.9×104 N/m2 (520 Torr)

30%

+50°C

+50°C

+10°C/hr (TBR)

1×105 N/m2 (760 Torr)

70%

Rationale: Derived from the Europa Propulsion Subsystem Spec, 597-EUROPA-SPEC-

5.2 QUASI-STATIC ACCELERATION

Quasi-static acceleration represents the combination of steady-state accelerations and the low frequency mechanically transmitted dynamic accelerations that occur during launch. The COPV shall demonstrate its ability to meet its performance requirements after being subjected to a net limit load of 40.0 g when pressurized to MEOP with helium.

Rationale: Derived from the Mass Acceleration Curve in D-80302, Environmental Requirements Document.

5.3 FREQUENCY REQUIREMENT

5.3.1 Fundamental Frequencies

The COPV shall have a fundamental frequency greater than 80 Hz when hard-mounted to the spacecraft structure.

Rationale: Derived from the Europa Propulsion Subsystem Spec, 597-EUROPA-SPEC-

001. The Mass Acceleration Curve is applied for a frequency of less than 80Hz.

5.4 VIBRATION

5.4.1 Sinusoidal Vibration

The COPV shall demonstrate its ability to meet its performance requirements after being subjected to the sine vibration environment in Table 4 applied at the mounting interface.

Table 4: Sine Vibration Environment

Frequency Acceptance Level Protoflight/Qual Level

5 - 15 8.8 g 11 g

15 - 35 8 g 10 g

35-60 16 g 20 g

Levels may be notched to not exceed 1.25 times the design limit load. These levels will be updated as coupled-loads analysis (CLA) data becomes available. The COPV shall test for this environment up to 50 Hz and be analyzed from 50 to 100 Hz.

Peak levels at the low end of the frequency range (5-20 Hz) may be ramped up as needed to accommodate table displacement capability per NASA/GSFC Contracting Office Representative (COR) review and approval during test verification of the sinusoidal vibration requirements.

Rationale: Derived from the Europa Propulsion Subsystem Spec, EUROPA-PROP- SPEC-0001 and directly from D-80302, Environmental Requirements Document.

5.4.2 Random Vibration

The COPV shall demonstrate its ability to meet its performance requirements after being subjected to the random vibration environment in

Table 5, applied at the COPV mounting interface.

Table 5: Random Vibration Levels

Frequency (Hz) FA Acceleration Spectral Density

Qualification and Protoflight Acceleration

Spectral Density

10 -100 +6 dB/oct +6 dB/oct

100 - 1200 0.125 g2/Hz 0.25 g2/Hz

1200 - 2000 -6 dB/oct -6 dB/oct

Overall 11.9 grms 16.8 grms

Qual: 2 minutes in each of the three axes. Protoflight and flight: 1 minute in each axis.

Peak levels at the low end of the frequency range (5-20 Hz) may be ramped up as needed to accommodate table displacement capability per NASA/GSFC COR review and approval during test verification of the random vibration requirements.

SPEC-0001 and directly from D-80302, Environmental Requirements Document.

5.5 SHOCK

The COPV shall be designed to meet its performance requirements after being subjected to the shock environment in Table 6 applied at the COPV mounting interface.

Table 6: Shock Levels

Frequency (Hz) Maximum Expected Flight Level (Flight Acceptance, FA)

Shock Response Spectrum

Maximum Expected Qualification Level (or Protoflight, PF)

Shock Response Spectrum

100 70 100

1500 950 1350

10000 950 1350

SPEC-0001 and directly from D-80302, Environmental Requirements Document.

5.6 EXTERNAL PRESSURE

The COPV shall be designed to meet all performance requirements while operating over a pressure range of 1.08 × 105 N/m2 (813 Torr) to 1.3 × 10-12 N/m2 (1 × 10-14 Torr).

5.7 HUMIDITY

The COPV shall be able to meet performance requirements after exposure to relative humidity levels of 0% to 70% for the defined mission life.

Rationale: Derived from the Europa Propulsion Subsystem Spec, EUROPA-PROP-

SPEC-0001.

5.8 THERMAL REQUIREMENTS

The COPV shall be capable of surviving indefinitely without damage or permanent performance degradation when its temperatures are within the qualification survival limits shown in Table 7.

Table 7: Temperature Levels

Minimum Temperature (ºC)

Maximum Temperature (ºC)

Allowable Flight Temperature -32 +35

Flight Acceptance -37 +40

Protoflight or Qualification -47 +55

6.0 CLEANLINESS

6.1 SURFACE CONTAMINATION & PLANETARY PROTECTION

6.1.1 Surface Contamination Levels at Delivery

Biological Contamination

All of the parts of the valve shall be treated per Planetary Protection protocols such that the bioburden is reduced by the required amount per Europa Planetary Protection Plan as outlined in the Pressurant Tank SOW, EUROPA-PROP-SOW-0008. These protocols shall not degrade the performance of the tank.

Rationale: Derived from JPL Europa Planetary Protection requirements.

External Cleanliness

The COPV external cleanliness shall meet IEST-VC-0.5-1000 per IEST-STD-CC1246, prior to delivery to NASA/GSFC.

Internal Cleanliness

The COPV internal cleanliness shall meet level 100A per IEST-STD-CC1246 (as modified by the following: no metal particles allowed above 25 um) prior to integration in the system.

Rationale: Derived from the Europa Propulsion Subsystem Spec, EUROPA-PROP-

SPEC-0001.

6.1.2 Material Selection

Material Requirements

The COPV materials chosen for the metallic liner and composite overwrapping shall meet the requirements listed in Section 5.3 of ANSI/AIAA S-081-2006.

Material Requirements

The COPV materials shall include a coating over the fibers that fluoresces when damaged.

Low Volatile Materials

The COPV materials shall have a total mass loss (TML) less than 1.00% and a collected volatile condensable mass (CVCM) less than 0.10%, as specified in ASTM E- 595 unless a materials usage agreement has been generated and approved by NASA/GSFC. Silicones should be avoided or minimized. It is highly recommended that silicones be baked out at a high temperature prior to integration into the system to prevent extended bake-outs of the entire assembly.

Rationale: Derived from the Europa Propulsion Subsystem Spec, EUROPA-PROP-

SPEC-0001.

Assembly Outgassing

When measured in a vacuum of 10-6 Torr at 50°C, the COPV outgassing shall not exceed 2×10-10 g/sec per kg of unit under test of mass that is condensable on a Quartz Crystal Monitor (QCM) that is operated at -20°C.

7.0 DESIGN & CONSTRUCTION REQUIREMENTS

7.1 IDENTIFICATION AND MARKING

The COPV shall be permanently marked with the part number, maximum operating pressure, and a unique sequential serial number in the area designated on the interface control drawing in a manner to be approved by the NASA/GSFC COR.

Rationale: Derived from the Europa Propulsion Subsystem Spec, EUROPA-PROP-

SPEC-0001.

7.2 INTERCHANGEABILITY

The COPV shall be directly interchangeable in form, fit, and function with other COPVs of the same part number.

Rationale: Derived from the Europa Propulsion Subsystem Spec, EUROPA-PROP-

SPEC-0001.

7.3 LIFETIME

The COPV shall be designed to operate for a minimum of 14.3 years as specified below:

- Integration and Test: 2 years

- Ground Storage: 1 year

- Mission Life: 11.3 years

APPENDIX A ABBREVIATIONS AND ACRONYMS (TBR)

Abbreviation/ Acronym Definition

AC Alternate Current

CCB Configuration Control Board

CCR Configuration Change Request

CLA Coupled-Loads Analysis

CM Configuration Management

CMO Configuration Management Office

COR Contracting Office Representative

CVCM Collected Volatile Condensable Mass

DC Direct Current

EEE Electrical, Electronic, and Electromechanical

EMI Electromagnetic Interference

EOL End of Life

FS Factor of Safety

GSFC Goddard Space Flight Center

I&T Integration and Test

MS Margin of Safety

MEOP Maximum Expected Operating Pressure

M Mega, 106

MGSE Mechanical Ground Support Equipment µ Micro, 10-6 m Milli, 10-3

Mohms Megaohms

MS Margin of Safety

N/A Not Applicable

NASA National Aeronautics and Space Administration

OD Outer Diameter

PSIA Pounds per Square Inch – Absolute

PSID Pounds per Square Inch – Differential

QCM Quartz Crystal Monitor

RE Radiated Emissions

RS Radiated Susceptibility

SC Spacecraft

SOW Statement of Work

STP Solar Terrestrial Probe

TBD To Be Determined

TBR To Be Reviewed

TML Total Mass Loss