CTSD-ADV-1082_Rev_C_Released_End_Item_Spec_FN_323_324.pdf

End Item Specification for the FN-323/324 – Oxygen

Ventilation Loop Fan Assembly Engineering Directorate

Crew and Thermal Systems Division

Verify this is the correct version before use

Date: July 23, 2018

Revision: C

CTSD-ADV-1082

National Aeronautics and Space Administration

Lyndon B. Johnson Space Center

Houston, Texas 77058

End Item Specification for the FN-323/324 – Oxygen Ventilation Loop Fan Assembly CTSD-ADV-1082 Rev C

REVISIONS

DATE AUTHOR DESCRIPTION REV. LETTER

4/28/14 C. Kelly Initial Release N/C

08/18/17 R. Ralston Updated operating life to include on/off cycles

Updated and added a number of requirements to match PLSS

Spec update

Added reference to Interface Control Drawing for the fan

A

11/16/17 R. Ralston Updated fan operating points B

7/23/18 R. Ralston Numerous updates to align with DVT goals. C iii

TABLE OF CONTENTS

Section Page

Table of Contents .........................................................................................................................................................iv

Table of Figures............................................................................................................................................................vi

Table of Tables.............................................................................................................................................................vi

1.0 Introduction

1.1 Scope

1.2 Conventions and Notations

1.2.1 Rationale

1.2.2 Designations and Prioritization

1.2.3 Background

1.2.4 Nomenclature

1.2.5 xPLSS Component Identifiers

1.3 Responsibility and Change Authority

2.0 Documents

2.1 Applicable Documents

2.2 Reference Documents

2.3 Interface Control Documents (ICD)

3.0 Oxygen Ventilation Loop Fan Assembly

3.1 Functional Overview

3.2 Performance Requirements

3.2.1 Life

3.2.1.1 [R.FAN.000.001] Operational Life

3.2.1.2 [R.FAN.000.002] Useful Life

3.2.1.3 [R.FAN.000.003] Shelf Life

3.2.1.4 [R.FAN.000.004] Launch/Landing Cycles

3.2.2 Operating Fluids

3.2.2.1 [R.FAN.000.005] Gaseous Nitrogen

3.2.2.2 [R.FAN.000.006] Gaseous Oxygen

3.2.2.3 [R.FAN.000.007] Gaseous Heliox

3.2.2.4 [R.FAN.000.008] Gaseous Helium and Nitrogen

3.2.2.5 [R.FAN.000.009] Atmospheric Air

3.2.3 [R.FAN.000.010] Operating Pressures

3.2.4 [R.FAN.000.011] External Leakage

3.2.5 [R.FAN.000.012] Cleanliness

3.2.6 [R.FAN.000.013] Ventilation Flow Operating Points

3.2.7 [R.FAN.000.014] Inlet Temperature

3.2.8 [R.FAN.000.015] Free Water Tolerance

3.2.9 Motor

3.2.9.1 [R.FAN.000.016] Operating Voltage Range

3.2.9.2 [R.FAN.000.017] Motor Type

3.2.9.3 [R.FAN.000.018] Motor Speed

3.2.10 Sensors

3.2.10.1 [R.FAN.000.019] Stator Temperature Sensor

3.2.10.2 [R.FAN.000.020] Stator Temperature Sensor Excitation

3.2.10.3 [R.FAN.000.021] Stator Temperature Accuracy and Range

3.2.10.4 [R.FAN.000.022] Hall Effect Device

3.2.10.5 [R.FAN.000.023] Hall Effect Excitation

3.2.11 [R.FAN.000.024] Mass

3.3 Environments

3.3.1 Pressure

3.3.1.1 [R.FAN.100.001] Ambient Pressure – Operational

3.3.1.2 [R.FAN.100.002] Ambient Pressure – Non-Operational

3.3.1.3 [R.FAN.100.003] Ambient Pressure Rate Decreasing – Operational

3.3.1.4 [R.FAN.100.004] Ambient Pressure Rate Decreasing – Non-Operational

3.3.1.5 [R.FAN.100.005] Ambient Pressure Rate Increasing – Operational iv

3.3.2 Temperature

3.3.2.1 [R.FAN.100.006] Environmental Temperature Profile

3.3.3 [R.FAN.100.007] External Humidity

3.3.4 [R.FAN.100.019] G-Field Orientation

3.3.4.1 [R.FAN.100.008] Acceleration – Launch Vehicles

3.3.4.2 [R.FAN.100.009] Acceleration – Survivable

3.3.4.3 [R.FAN.100.010] Random Vibration – Operating

3.3.4.4 [R.FAN.100.011] Random Vibration – Non-Operating

3.3.5 [R.FAN.100.012] DC Magnetic Field

3.3.6 [R.FAN.100.013] Salt Fog

3.3.7 [R.FAN.100.014] Fungus

3.3.8 [R. FAN.100.015] Ozone

3.3.9 [R.FAN.100.016] Ionizing Radiation

3.3.10 [R.FAN.100.017] Atomic Oxygen

3.3.11 [R.FAN.100.018] Atmospheric Composition

3.4 Induced Environmental Contributions

3.4.1 Noise

3.4.1.1 [R.FAN.200.001] Fan Noise

3.4.1.2 [R.FAN.200.002] External Noise

3.5 Safety

3.5.1 [R.FAN.300.001] Catastrophic Hazards

3.5.2 [R.FAN.300.002] Critical Seal Redundancy

3.5.3 [R.FAN.300.003] Leakage Beyond Secondary Oxygen Make-up

3.6 Design and Construction

3.6.1 [R.FAN.400.001] Materials and Processes

3.6.2 [R.FAN.400.002] Part Identification

3.6.3 [R.FAN.400.003] Like-Component Interchangeability

3.6.4 [R.FAN.400.004] Common Fasteners

3.6.5 [R.FAN.400.005] Oxygen Compatibility Assessment

3.6.6 [R.FAN.400.006] Mechanical Structural Margin

3.6.7 [R.FAN.400.007] Combined Structural Margin

3.6.8 [R.FAN.400.008] Toxic Off-Gassing

3.6.9 [R.FAN.400.009] Vacuum Stability

3.6.10 [R.FAN.400.010] Welding

3.6.11 [R.FAN.400.011] Fragment Containment

3.6.12 [R.FAN.400.012] General Workmanship

3.6.13 [R.FAN.400.013] Crimping, Interconnecting Cables, Harnesses, and Wiring

3.6.14 [R.FAN.400.014] Soldered Electrical and Electronic Assemblies

3.6.15 [R.FAN.400.015] Electrostatic Discharge Design

3.6.16 [R.FAN.400.016] Electrostatic Discharge Protection

3.6.17 [R.FAN.400.017] Corrosion Control

3.6.18 [R.FAN.400.018] Sharp Edge Limits

3.6.19 [R.FAN.400.019] Fastener Design

3.6.20 [R.FAN.400.020] Fastener Integrity

3.6.21 [R.FAN.400.021] Grounding

3.6.22 [R.FAN.400.022] Electronic, Electrical, and Electromechanical (EEE) Parts

3.6.23 [R.FAN.400.023] Parts Derating

3.6.24 [R.FAN.400.024] Destructive Physical Analysis (DPA)

3.6.25 [R.FAN.400.025] Fracture Control

3.7 Interface Control

3.7.1 [R.FAN.500.001] Interface Control Document

4.0 Fan 3.0 Verification Matrix

Appendix A - Acronyms and Abbreviations v

TABLE OF FIGURES

Figure Page

Figure 1-1 – PLSS Development Fans (Fan 1.0 on Left, Fan 2.0 on Right)

Figure 1-2 – Fan ORU Assembly

Figure 3-2 – xEMU Random Vibration Profile

TABLE OF TABLES

Table Page

Table 1-1 – Requirements Nomenclature Key

Table 1-2 – Fan Component Identifiers

Table 2-1 – Applicable Documents

Table 2-2 – Reference Documents

Table 2-3 – Interface Control Documents

Table 3-1 – Operational Duration and Cycles

Table 3-2 – Operating Pressures Table

Table 3-3 – External Leakage

Table 3-4 – Cleanliness Table

Table 3-5 – Ventilation Flow Operating Points

Table 3-6 – Design Load Factors for Launch Vehicles

Table 3-7 – Design Load Factors for Launch Vehicles

Table 3-8 – Fan Random Vibration Profile – Operating

Table 3-9 – xEMU Random Vibration Profile

Table 3-10 – Ionizing Radiation Dosage

Table 3-11 – Fan Internal Noise Output

Table 3-12 – Fan-Generated Noise

Table 3-13 – Common Fasteners

Table 3-14 – Corners and Edges

Table 4-1 – Verification Matrix vi

1.0 INTRODUCTION

1.1 SCOPE

This specification establishes the requirements for design, performance, safety, and manufacture of the FN-323/324 – Oxygen Ventilation Loop Fan Assembly as part of the Exploration Extravehicular Mobility Unit (xEMU) Exploration

Portable Life Support Subsystem (xPLSS).

1.2 CONVENTIONS AND NOTATIONS

1.2.1 RATIONALE

A rationale statement is included for each requirement. The rationale statement indicates why the requirement is needed, shows the basis for its inclusion in this requirements document, and provides context and examples to stakeholders. It is important to note that rationale is not binding, and it only provides supporting information. In the event that there is an inconsistency between the requirement and the rationale, the requirement is binding and takes precedence. If there is any confusion between the requirement and rationale, seek further guidance from the responsible technical authority.

1.2.2 DESIGNATIONS AND PRIORITIZATION

The convention used in this document to indicate requirements, goals, and statements of fact is as follows:

355BDesignation Description

“Shall” used to indicate a requirement that must be implemented and its implementation verified

“Should” used to indicate a goal that must be addressed by the design, but is not formally verified

“Will” used to indicate a statement of fact, and is not verified

1.2.3 BACKGROUND

Fan development for the advanced PLSS began in 2009 with the development of Fan 1.0. This fan was used in PLSS

2.0 for circulation of the ventilation loop gas. Figure 1-1 shows both Fans 1.0 and 2.0. Fan 2.0 was delivered in 2015 and was used in the PLSS 2.5-301 Live Loads test series. This fan used the same motor as Fan 1.0, but had a larger volute and impeller to achieve lower speeds at the PLSS operating points. The PLSS fan requirements also changed between Fan 1.0 and Fan 2.0 development. The next iteration of the advanced xPLSS fan, Fan 3.0, is the subject of the requirements contained within this document, and will be used with the xPLSS 2.5-302 configuration.

Figure 1-1 – PLSS Development Fans (Fan 1.0 on Left, Fan 2.0 on Right)

1.2.4 NOMENCLATURE

Each requirement contained in this development specification is denoted by a unique identifier (Error! Reference source not found.) that transcends traditional paragraph numbering to keep requirements traceability clearer and more achievable.

Table 1-1 – Requirements Nomenclature Key

Requirement Nomenclature xPLSS Sub-Assembly or Loop

[R.FAN.000.XXX] Fan Performance Requirements

[R.FAN.100.XXX] Fan Environmental Requirements

[R.FAN.200.XXX] Fan Induced Environmental Requirements

[R.FAN.300.XXX] Fan Safety Requirements

[R.FAN.400.XXX] Fan Design and Construction Requirements

[R.FAN.500.XXX] Fan Interface Control Requirements

1.2.5 XPLSS COMPONENT IDENTIFIERS

The xPLSS uses unique identifiers for each of the components as shown in Table 1-2.

Table 1-2 – Fan Component Identifiers

Item Description

FN-323 Oxygen Ventilation Loop Fan, Primary

FN-323A Fan, Primary

FN-323B BLDC Motor, Fan

FN-323D RTD, Stator Temperature

FN-324 Oxygen Ventilation Loop Fan, Secondary

FN-324A Fan, Secondary

FN-324B BLDC Motor, Fan

FN-324D RTD, Stator Temperature

The fan Orbital Replacement Unit (ORU) assembly in the xPLSS 2.5 design consists of the following items: FN-323, FN-324, a check valve for each fan, a fan inlet manifold, and a fan outlet manifold. Fan FN-323 is the primary fan, and FN-324 is the secondary fan. FN-324 will be powered off while FN-323 is operating, acting as a cold spare. They are of the same design, and differ only in serial number. The current fan ORU is shown in Figure X Below.

Figure 1-2 – Fan ORU Assembly

1.3 RESPONSIBILITY AND CHANGE AUTHORITY

The Space Suit and Crew Survival Systems Branch within the Crew and Thermal Systems Division (CTSD) is responsible for the development and management of the CTSD-ADV-1082, End Item Specification for the FN

323/324 – Oxygen Ventilation Loop Fan Assembly.

2.0 DOCUMENTS

The documents listed in this section represent those that have been identified either in part or in whole within this document.

2.1 APPLICABLE DOCUMENTS

The applicable documents (Table 2-1) are those that have been explicitly identified within requirements statements

(i.e., “shall” statements) and are invoked as technical requirements, in part or in whole, for implementation. Each requirement statement identifies the applicable subsections of a document, unless it has been deemed appropriate to invoke the entire document.

Table 2-1 – Applicable Documents

Document Number Document Title

ANSI/ESD S20.20-2014 Protection of Electrical and Electronic Parts, Assemblies, and Equipment

IEC 60751 Edition 2.0 Industrial Platinum Resistance Thermometers and Platinum Temperature Sensors

JPR 5322.1 Rev H Contamination Control Requirements Manual

J-STD-01 Rev G Requirements for Soldered Electrical and Electronic Assemblies

IPC J-STD-001GS Space and Military Applications Electronic Hardware Addendum to J-STD-001G

IPC-2222A Sectional Design Standard for Rigid Organic Printed Boards

IPC-2223D Sectional Design Standard for Flexible/Rigid-Flexible Printed Boards

MIL-PRF-27210 Rev J Performance Specification for Oxygen, Aviator’s Breathing, Liquid and Gas

MIL-PRF-27401 Rev G Performance Specification for Propellant Pressurizing Agent, Nitrogen

MIL-PRF-27407 Rev D Performance Specification for Propellant Pressurizing Agent, Helium

MIL-STD-130 DOD Standard Practice: Identification Marking of U.S. Military Property

MIL-STD-1580

DOD Test Method Standard: Destructive Physical Analysis for Electronic, Electromagnetic, and Electromechanical Parts

MIL-STD-1686 Rev C

DOD Standard Practice: Electrostatic Discharge Control Program for Protection of

Electrical and Electronic Parts, Assemblies and Equipment (Excluding Electrically

Initiated Explosive Devices)

MIL-STD-750-1

Rev A w/Change 2

DOD Test Method Standard: Environmental Test Methods for Semiconductor

Devices, Part 1: Methods 1000 through 1999

MIL-STD-810

Rev G w/Change 1

DOD Test Method Standard: Environmental Engineering Considerations and

Laboratory Tests

NASA-STD-5006

Rev A w/Change 1

General Fusion Welding Requirements for Aerospace Materials

NASA-STD-5020

Baseline

Requirements for Threaded Fastening Systems in Spaceflight Hardware

NASA-STD-6008

Baseline w/Change 1

NASA Fastener Procurement, Receiving Inspection, and Storage Practices for

Spaceflight Hardware

NASA-STD-6012

Baseline

Corrosion Protection for Space Flight Hardware

NASA-STD-6016

Rev A

Standard Materials and Processes Requirements for Spacecraft

NASA-STD-8739.4

Rev A

Workmanship Standard for Crimping, Interconnecting Cables, Harnesses, and Wiring

NASA-STD-8739.6

Rev A w/Change 1

Implementation Requirements for NASA Workmanship Standards

SLN13102232?

Rev 1

PLSS Fan 323/324?

SSP 30233

Rev H

Space Station Requirements for Materials and Processes

Document Number Document Title

SSP 30309 Safety Analysis and Risk Assessment Requirements Document

SSP 30312, Vol I

Rev L

Electrical, Electronic, and Electromechanical (EEE) Parts Management and

Implementation Plan for the Space Station Program

SSP 30512 Space Station Ionizing Radiation Design Environment

SSP 30558

Rev C

Fracture Control Requirements for Space Station

SSP 30559

Rev D

ISS Structural Design and Verification Requirements

SSP 50021 Safety Requirements Document

2.2 REFERENCE DOCUMENTS

Documents that are identified, but are not invoked within requirements statements, are listed in Table 2-2.

Table 2-2 – Reference Documents

Document Number Document Title

ANSI/ASA S12.2 American National Standard Criteria for Evaluating Room Noise

CTSD-ADV-780

Development Specification for the Advanced EMU (AEMU) Portable Life Support

System (PLSS)

CTSD-ADV-959

Schematics and Behavioral Description for the Advanced EMU (AEMU) Portable Life

Support Subsystem (PLSS)

JSC 16646 Shuttle EMU Thermal Vacuum Test Report, 1982

JSC-63309 Recommendations for Exploration Spacecraft Internal Atmospheres

SSP 30240

Rev H

Space Station Grounding Requirements

SSP 30423

Rev L

Space Station Approved Electrical, Electronic, and Electromechanical (EEE) Parts

List

SSP 41172

Rev AD

Qualification and Acceptance Environmental Test Requirements

SSP 50835

Rev D

ISS Pressurized Volume Hardware Common Interface Requirements Document

TR-2004(8583)-1 Test Requirements for Launch, Upper Stage, and Space Vehicles

2.3 INTERFACE CONTROL DOCUMENTS (ICD)

The document listed in Table 2-3 identifies the interfaces between the fan component and the remaining xPLSS system.

Table 2-3 – Interface Control Documents

Document Number Document Title

SLN13103091 Rev 1 PLSS Fan 323/324

3.0 OXYGEN VENTILATION LOOP FAN ASSEMBLY

This section contains the technical design and performance requirements.

3.1 FUNCTIONAL OVERVIEW

The function of the Oxygen Ventilation Loop Fan Assembly is to provide breathing gas circulation within the Space

Suit Assembly (SSA) under a range of load conditions and SSA configurations.

3.2 PERFORMANCE REQUIREMENTS

3.2.1 LIFE

3.2.1.1 [R.FAN.000.001] OPERATIONAL LIFE

The fan shall have an operating life as specified in Table 3-1.

Table 3-1 – Operational Duration and Cycles

Component Function Minimum

Duration (hrs)

On/Off Cycles

FN-323/FN-324, Fan Circulate ventilation loop gas 4000(1) 11600(2)

Rationale: The goal is to make the hardware and its associated certification “robust-enough” such that detailed tracking of operating cycles and the resultant operational over-head are not required.

(1) This is based on 100 extravehicular activities (EVA) at 8 hours per EVA and 2 hours pre/post-EVA functional time for pre-breathe and other activities with a scatter factor of 4, per CTSD-ADV-780, Development Specification for the Advanced EMU (AEMU) Portable Life Support System (PLSS).

(2) This is based on 2 cycles per 100 EVAs with monthly In-Flight Maintenance (IFM) cycles over a 6 year operational period with another 1250 cycles to cover Pre-Installation Acceptance (PIA), ground testing, and preflight checks. This is then multiplied by 2 (2 flight tours), all multiplied by a scatter factor of 4. A single cycle is defined as going from OFF to ON and back to OFF.

3.2.1.2 [R.FAN.000.002] USEFUL LIFE

The fan shall have a useful life of 15 years minimum without refurbishment, assuming that the usage rate does not exceed operational life [R.FAN.000.001].

Rationale: The useful life is the total chronological time that an assembly, component, or detail part may be used.

It is the total of shelf life and operational life. Useful life begins at the item’s birth date, which can be initial acceptance, date of manufacture, date of cure, etc. The component may sit on the shelf in controlled storage for 15 years until it expires, it may be placed into service for 15 years (but within the operational life) until it expires, or some combination with the total tracked time of 15 years and total operating hours as defined in the operational life.

3.2.1.3 [R.FAN.000.003] SHELF LIFE

The fan shall have a shelf life of 15 years minimum.

Rationale: This allows for program logistics flexibility without recertification.

3.2.1.4 [R.FAN.000.004] LAUNCH/LANDING CYCLES

The fan shall tolerate and operate after 9 launch and landing cycles minimum.

Rationale: The intent is to dictate that the fan will be designed for multiple launches and landings to support its as yet undetermined missions. The details of what each launch/landing cycle entails depends on the vehicle chosen, but is encompassed by the requirements provided in the environments section.

3.2.2 OPERATING FLUIDS

3.2.2.1 [R.FAN.000.005] GASEOUS NITROGEN

The fan shall be compatible with and operate using gaseous nitrogen per MIL-PRF-27401, Performance Specification for Propellant Pressurizing Agent, Nitrogen, Type I, Grade B, as a test fluid.

Rationale: Gaseous nitrogen provides a safe and effective method for performing development tests before oxygen compatibility testing and approval. It will be the gas used for a variety of fan and xPLSS-level tests.

3.2.2.2 [R.FAN.000.006] GASEOUS OXYGEN

The fan shall be compatible with and operate using gaseous oxygen per MIL-PRF-27210, Performance Specification for Oxygen, Aviator’s Breathing, Liquid and Gas, Type I, as the working fluid.

Rationale: The primary function of the fan is to circulate the oxygen in the ventilation loop of the gas. To fulfill this function, all wetted components must be oxygen-compatible and cleaned for oxygen use, as stated in [R.FAN.000.012] Cleanliness.

3.2.2.3 [R.FAN.000.007] GASEOUS HELIOX

The fan shall be compatible with and operate using a mixture of 0.5% +/- 0.02% helium per MIL-PRF-27407, Performance Specification for Propellant Pressurizing Agent, Helium, Grade A, with balance gaseous oxygen per

MIL-PRF-27210, Type I as the working fluid.

Rationale: Gaseous heliox provides increased resolution for preflight leakage checks, but is not anticipated as working fluid during mission events.

3.2.2.4 [R.FAN.000.008] GASEOUS HELIUM AND NITROGEN

The fan shall be compatible with and operate using a mixture of 0.5% + 0.02% helium per MIL-PRF-27407, Grade

A, with balance gaseous nitrogen per MIL-PRF-27401G, Performance Specification for Propellant Pressurizing

Agent, Nitrogen, Type I, Grade B, as a test fluid.

Rationale: Gaseous helium provides increased resolution for preflight acceptance leakage checks, but is not anticipated as working fluid during mission events. This is relevant to the primary, secondary, and ventilation loops.

3.2.2.5 [R.FAN.000.009] ATMOSPHERIC AIR

The fan shall be compatible with and operate using atmospheric air described as follows:

Composition

Gaseous Oxygen 20 +/- 5%

Gaseous Nitrogen 80 +/- 5% (balance)

Humidity

25% RH at 80°F dry bulb to 85% RH at 65°F dry bulb

Rationale: In some situations, the gas used to repress the airlock, which is the working fluid for the Negative

Pressure Relief Valve (NPRV), will be ambient air. This air may or may not be conditioned or managed beyond that described. This also provides the capability to use ambient air for ground testing of the fan.

3.2.3 [R.FAN.000.010] OPERATING PRESSURES

The fan shall have operating pressures as described in Table 3-2.

Table 3-2 – Operating Pressures Table

Operating Pressure *Oxygen Ventilation Loop kPa (diff)

[psid]

*Maximum Design Pressure (MDP)(1) 73.1

[10.6]

*Structural Pressure (1.1 x MDP)(2) 80.4

[11.7]

*Proof Pressure (1.5 x MDP) 110.0

[15.9]

*Minimum Allowable Burst Pressure (2.5 x MDP)(3) 183

[26.5]

Minimum Allowable Collapse Pressure(4) 104.8

[15.2]

Rationale:

(1) The Maximum Design Pressure (MDP) for the Oxygen Ventilation Loop is based on the pressure at full-open flow for RV-348, one of the xEMU positive pressure relief valves, with 0.5 psid margin at

10.6 psid.

(2) Structural pressure testing for the Pressure Garment System (PGS) as attached to the Oxygen

Ventilation Loop is 1.5 x Nominal Operating Pressure (NOP), defined as 8.8 units? *1.5 = 13.2 psid.

This will be done separately and does not apply to the fan. When assembled to the xPLSS, the structural pressure will be as defined in this table.

(3) This satisfies SSP 30559, ISS Structural Design and Verification Requirements, Table 3.3.1-1 Factors of Safety for Test Verified Structure, Sub paragraph C.3.d (Actuating cylinders, valves, filters, etc.).

(4) Collapse pressure is the pressure at which a negatively or externally loaded pressure vessel will collapse on itself. This is mainly useful for ensuring that helium leakage testing can be performed where the fan is at vacuum internally, but surrounded by ambient pressure externally. The maximum expected pressure of a cabin environment is 15.2.

*For the first four rows of this table, the greater pressure is on the inside of the fan. Only the collapse pressure has the greater pressure outside of the fan.

3.2.4 [R.FAN.000.011] EXTERNAL LEAKAGE

The fan shall limit external leakage, as indicated in Table 3-3, when at an internal pressure of 8.4 psia over vacuum ambient and a gas temperature of 60°F.

Table 3-3 – External Leakage

GOX (kg/sec) GOX (lb/hr) GOX (lab equivalent) (lb/hr)(1) GN2 (lab equivalent) (lb/hr)(1)

7.54E-13 5.98E-09 1.33E-08 1.24E-08

Rationale: The entire xPLSS Oxygen Ventilation Loop leakage allocation is 2.22E-09 kg/sec (1.77E-05 lb/hr) of

GOX; component leakage rate is based on the analytical estimates from assumed construction, as specified in CTSD-ADV-780, Development Specification for the Advanced EMU (AEMU) Portable Life

Support System (PLSS).

(1) The “lab equivalent” numbers are based on sea level ambient pressure conditions and an internal differential pressure of 8.4 psid while at 70°F.

3.2.5 [R.FAN.000.012] CLEANLINESS

The fan shall have cleanliness levels per JPR 5322.1, Contamination Control Requirements Manual, as dictated per

Table 3-4.

Table 3-4 – Cleanliness Table

Cleanliness Level Internal Surfaces(1) External Surfaces

Initial Build(2) 150A VC

Maintained 150 GC

Rationale:

(1) The ventilation loop is originally cleaned to an “A” rating of less than 1 mg/ft2 of non-volatile residue

(NVR). This can be verified using precision cleaning solvent evaporation and gravimetric analysis.

It cannot be verified during operation at the system level with the presence of a human and other components in the ventilation loop because the assembled and lubricated system will not be conducive to the solvent flush needed to verify the NVR level.

(2) The initial build refers to the cleaning level of parts before assembly. The fan should be delivered to the customer with the inlet and outlet ports sealed to maintain cleanliness. The assembly should also be double-bagged to help maintain cleanliness.

3.2.6 [R.FAN.000.013] VENTILATION FLOW OPERATING POINTS

The fan shall provide flow and head-rise in 100% oxygen gas per maximizing the total efficiency(1) at Operating Point 1.

Table 3-5 – Ventilation Flow Operating Points

Operating

Point

Volumetric

Flowrate

Lpm [acfm]

Fan Inlet

Pressure kPa [psia]

Fan Inlet Gas

Temperature

°C [°F](2)

Minimum

Head Rise

Pa [in-H2O]

Maximum

Power

Draw (W)

Voltage

(V)

1 150 [5.3] 29.7 [4.3] 26.7 [80.0] 1219 [4.9] 11.7 22

2 150 [5.3] 56.5 [8.2] 26.7 [80.0] 2314 [9.3] 22.2 22

3 150 [5.3] 104.1 [15.1](4) 26.7 [80.0] 4280 [17.2] 41.0 22

4 150 [5.3] 163 [23.6](3) 26.7 [80.0] 6694 [26.9] 64.0 22

Rationale: These operating points ensure that the ventilation loop can maintain flow requirements with the attached SSA and are listed in order of priority with respect to fan operating point optimization. It is anticipated that the suit will be operated most frequently at operating point 1; operating points 2 and 3 are permitted to have less relative efficiency.

(1) Total efficiency is defined as total power added to the air over power input to the fan motor.

(2) The suit gas temperature is increased over previous values used because of the relocation of the fan within the xPLSS ventilation loop. It is now located at the outlet of the SSA, which is anticipated to be in the 70° to 80°F range under most thermal environments and metabolic rate ranges. (Reference

JSC 16646, Shuttle EMU Thermal Vacuum Test Report, 1982).

(3) The suit pressure is composed of a maximum decompression sickness (DCS) treatment pressure setting of 8.4 psig over an increased cabin pressure of 15.2 psia.

(4) The suit pressure during intravehicular activity (IVA) operations would nominally be 0.4 psid above a cabin pressure of 14.7 psia resulting in 15.1 psia.

3.2.7 [R.FAN.000.014] INLET TEMPERATURE

The fan shall operate given a gas inlet temperature between 1.67°C [35°F] and 51.7°C [125°F].

Rationale: The typical temperature range is around 60°F to 100°F; however, there are test conditions and off nominal conditions outside of this range that the fan may encounter. Temperatures in the EMU have achieved over 104°F during pre-breathe to help condition the MET-OX CO2 removing canister. While this would not be a necessary protocol for an RCA-based CO2 removal capability, higher temperatures are expected in the suit from crew comfort as well.

3.2.8 [R.FAN.000.015] FREE WATER TOLERANCE

The fan shall operate while passing a minimum of 251 cc [8 fl oz] injected at the inlet at a rate of 60 cc/min.

Rationale: The xPLSS design does not intend to have free water present in the ventilation loop as a nominal condition, but with an inlet from the SSA, there are multiple failure modes that could provide free water ingestion (i.e., drink bag rupture). This requirement is intended to make the design tolerable of free water passage in an attempt to have a more robust system overall. Initial water sequestration capability has been analyzed per JETS-JE33-13-TAED-DOC-0005.

3.2.9 MOTOR

3.2.9.1 [R.FAN.000.016] OPERATING VOLTAGE RANGE

The fan shall operate at all design points with an input rail voltage of 22 to 34 Volts Direct Current (VDC).

Rationale: The attached controller will accept an input supply of 22-34 VDC from the xPLSS.

3.2.9.2 [R.FAN.000.017] MOTOR TYPE

The fan shall include a 3-phase Wye connected, 4-pole BLDC motor.

Rationale: The motor connections are needed to maintain an interface to the CON-350, Oxygen Ventilation Loop

Controller within the xPLSS.

3.2.9.3 [R.FAN.000.018] MOTOR SPEED

The fan shall perform at all operating points without exceeding 50,000 revolutions per minute (RPM).

Rationale: The Oxygen Ventilation Loop Controller (CON-350) will be designed to control up to this speed. A variety of speeds are desired for flexibility in lab testing to allow the ventilation flow rate to be adjusted, if necessary, when the fan is installed in the xPLSS.

3.2.10 SENSORS

3.2.10.1 [R.FAN.000.019] STATOR TEMPERATURE SENSOR

The fan shall provide a 1000 Ohm Resistance Temperature Detector (RTD) integrated to the motor to monitor stator temperatures.

Rationale: This enables the monitoring of motor health to ensure that waste heat is being properly dissipated before degradation of the insulation resistance for windings. This is referred to as FN-323D in the xPLSS 2.5 schematic.

3.2.10.2 [R.FAN.000.020] STATOR TEMPERATURE SENSOR EXCITATION

The fan stator temperature sensor shall operate fully with an excitation of 1mA or less.

Rationale: The Oxygen Ventilation Loop Controller (CON-350) will provide this excitation; therefore, the RTD needs to work with this excitation. A lower excitation current will provide a more accurate RTD by reducing the self-heating error.

3.2.10.3 [R.FAN.000.021] STATOR TEMPERATURE ACCURACY AND RANGE

The temperature sensor that monitors the fan stator temperature shall meet tolerance class A, B, or C as defined in

IEC 60751, Industrial Platinum Resistance Thermometers and Platinum Temperature Sensors, Edition 2.0, paragraph

5.1.3.

Rationale: This ensures that the fan motor temperature can be gathered within a reasonable accuracy. This will also ensure that the full range of expected motor temperatures will be read.

3.2.10.4 [R.FAN.000.022] HALL EFFECT DEVICE

The fan shall include a Hall Effect Device (HED) for each motor phase that generates Transistor-Transistor Logic

(TTL) level outputs for each phase of the motor. HED’s shall have 120 electrical spacing

Rationale: The HEDs are required to commutate the BLDC motor without using more elaborate algorithms that infer the armature position.

3.2.10.5 [R.FAN.000.023] HALL EFFECT EXCITATION

The fan HEDs shall be excited by a voltage between 4.5 and 5.5 VDC.

Rationale: The Oxygen Ventilation Loop Controller (CON-350) will provide this excitation, but the HEDs should be designed to use this excitation.

3.2.11 [R.FAN.000.024] MASS

The fan shall have a mass that is less than 0.68 kg [1.5 lbs] in flight configuration.

Rationale: This is based on the mass allocation from CTSD-ADV-780, Subsystem Specification for the Exploration

EMU Portable Life Support System (PLSS). This mass does not include the check valves or fan manifolds, and only includes the fan assembly itself.

3.3 ENVIRONMENTS

3.3.1 PRESSURE

3.3.1.1 [R.FAN.100.001] AMBIENT PRESSURE – OPERATIONAL

The fan shall operate in an external pressure environment ranging from at least 0.0 to 105 kPa [0.0 to 15.2 psia].

Rationale: The selected pressure spans from hard vacuum experienced in space away from support vehicles to ambient pressure at sea level locations such as those at NASA Johnson Space Center (JSC). This also includes the slightly higher pressure at which the ISS is permitted to operate: ~15.2 psia.

3.3.1.2 [R.FAN.100.002] AMBIENT PRESSURE – NON-OPERATIONAL

The fan shall operate after exposure to an external pressure environment ranging from 0.0 to 130 kPa [0.0 to 18.9 psia].

Rationale: This addresses the range of pressure regimes across the potential launch vehicles with Progress being the driving case on the upper end, and vacuum being common to some cargo vehicles.

3.3.1.3 [R.FAN.100.003] AMBIENT PRESSURE RATE DECREASING – OPERATIONAL

The fan shall operate during and after an ambient environment pressure drop of -156 torr/min [-3 psi/min] for up to

4.8 minutes.

Rationale: This is an approximate depress rate for the U.S. Airlock. The range of depress rates possible for a suit port connection to a Lunar Electric Rover or other similarly equipped vehicle has not been considered.

3.3.1.4 [R.FAN.100.004] AMBIENT PRESSURE RATE DECREASING – NON-OPERATIONAL

The fan, while installed in a stowed xPLSS, shall operate after exposure to an external environmental pressure drop of at least -6000 torr/min [-116 psi/min] for approximately 7 seconds.

Rationale: The driving requirement is derived from the depress curve of the Progress launch vehicle.

3.3.1.5 [R.FAN.100.005] AMBIENT PRESSURE RATE INCREASING – OPERATIONAL

The fan shall function at operating points 1, 2, and 3 listed in [R.FAN.000.013] during and after an ambient environment pressure increase of 6.9 kPa/sec [1 psi/sec] for 15 seconds.

Rationale: This is analogous to repressing a vacuum chamber from hard vacuum (10-6 torr) to sea level (14.7 psia) within 15 seconds. This would be the case if there were an emergency repress event following an

EVA.

3.3.2 TEMPERATURE

3.3.2.1 [R.FAN.100.006] ENVIRONMENTAL TEMPERATURE PROFILE

The fan shall operate during exposure to an ambient external temperature of 1.67°C [35°F] to 51.7°C [125°F].

Rationale: This is intended to provide a thermal bounding range for the fan inside the xPLSS volume given external heat fluxes, internal heat sources, thermal mass, duty cycle, etc. Reference JETS-JE33-16

TAED-DOC-0021, PLSS 2.5 Thermal Hydraulic Performance Analysis, for expected fan temperatures in various environments.

3.3.3 [R.FAN.100.007] EXTERNAL HUMIDITY

The fan shall operate in an environment with Relative Humidity (RH) cycling between 30 + 10% and 80 + 10% for ten 24-hour cycles per MIL-STD-810G, Method 507.6 Humidity, Induced Cycle B3.

Rationale: This specification is identical to what was used for the Space Shuttle EMU. While there are few, if any, instances where this will actually be required as an operational environment during micro-gravity, Lunar or Mars EVAs, relative humidity in the lab or in chamber tests, especially upon man-lock repress, does provide a measure of this sort of exposure. This test will be a conservative screen for potential materials or hermeticity issues. A cycle is defined as a variation in temperature from 25 +

5°C [77 + 9°F] and 30 + 10% RH to 65 + 5°C [149 + 9°F] and 80 + 10% RH and back over for 24 hours.

3.3.4 [R.FAN.100.019] G-FIELD ORIENTATION

The fan shall meet all requirements in any orientation for the following G-fields.

Orientations G-field (g) Location

All 0 Low Earth Orbit, Space

All 0.17 Lunar Surface

All 0.38 Mars Surface

All 1.0 Earth Surface

Rationale: The xPLSS may be operated in a variety of G-fields; therefore, the fan needs to operate fully in any of these fields, and in any orientation.

3.3.4.1 [R.FAN.100.008] ACCELERATION – LAUNCH VEHICLES

The fan shall operate nominally after exposure to the accelerations identified in Table 3-6.

Table 3-6 – Design Load Factors for Launch Vehicles

Nx (g) Ny (g) Nz (g) Rx (rad/sec2) Ry (rad/sec2) Rz (rad/sec2)

Launch +/- 7.0 +/- 4.0 +/- 4.0 +/-13.5 (1) +/-8.5 (1) +/-11.5 (1)

Rationale: The values listed envelop the ground transportation loads and the following launch vehicles: Progress, HTV, Atlas V, and Delta IV.

(1) While the xPLSS will not be launched on ATV or Soyuz, it is ideal to keep those options open for a fan ORU; therefore, the fans need to tolerate the vehicles’ rotational accelerations.

(2) The reference frame for the enveloped load factors is as follows:

a. X: The longitudinal axis of the vehicle. Positive X-axis extends from the base or bottom of the spacecraft to the nose of the spacecraft.

b. Y: Y axis is perpendicular to the x axis.

c. Z: Z axis is perpendicular to the x and y axes and completes the right-handed coordinate system.

3.3.4.2 [R.FAN.100.009] ACCELERATION – SURVIVABLE

The fan shall meet remain contained and intact after exposure to the accelerations identified in

. The values listed envelop the ground transportation loads and the following launch vehicles: Progress, HTV, Dragon, ATV, Atlas V, and Delta IV.

Table 3-7 – Design Load Factors for Launch Vehicles

Nx (g) Ny (g) Nz (g) Rx (rad/sec2) Ry (rad/sec2) Rz (rad/sec2)

Launch +9.0/-7.0 +/- 4.0 +/- 4.0 +/- 13.5 +/- 8.5 +/- 11.5

Landing +/-10.0 +/-6.6 +/-6.6 - - -

Rationale: Values obtained from SSP-50835, ISS Pressurized Volume Hardware Common Interface Requirements

Document, Rev D, Table 3.1.1.2.1.1.1-1, inclusive of PIRN 0022b.

3.3.4.3 [R.FAN.100.010] RANDOM VIBRATION – OPERATING

The fan shall operate during and after exposure to the vibration profile shown in Table 3-8, for a minimum of 30 minutes in each axis.

Table 3-8 – Fan Random Vibration Profile – Operating

FREQUENCY (Hz) LEVEL

10 – 40 0.0549 g2/Hz

40 – 500 -5.49 dB/oct

500 0.0006 g2/Hz

COMPOSITE 2.00 grms

Rationale: The fan needs to tolerate transport across terrestrial surfaces as part of a roving vehicle demonstration followed by eventual flight usage on a roving vehicle in the Lunar and Martian environments. The selection of time per axis is currently arbitrary given that the final vehicle configurations and operations concepts are not known. The vibration profile is more aggressive than the original MIL

STD-810G, Method 514.7, Category 4, Common Carrier – US Highway Truck vibration reference.

This particular profile was the limit profile (2 grms) in which the Primary Oxygen Regulator 2.0 design successfully operated in all axes without issue. It was also tested up to 3.3 grms with some regulation anomalies.

3.3.4.4 [R.FAN.100.011] RANDOM VIBRATION – NON-OPERATING

The fan shall operate during and after exposure to the vibration profile, shown in Table 3-9 and Figure 3-1, for a minimum of 30 minutes in each axis.

Table 3-9 – xEMU Random Vibration Profile

FREQUENCY (Hz) LEVEL

20 – 153 0.057 g2/Hz

153 – 190 +7.67 dB/oct

190 – 250 0.099 g2/Hz

250 – 750 -1.61 dB/oct

750 0.055 g2/Hz

750 – 2000 -3.43 dB/oct

FREQUENCY (Hz) LEVEL

2000 0.018 g2/Hz

COMPOSITE 9.47 grms

Duration 60 sec for 1 launch

Figure 3-1 – xEMU Random Vibration Profile

Rational:

(1) The flight package for the xPLSS or Fan ORU has not yet been defined, but is assumed to be a

“soft-stow” approach similar to the EMU Launch Enclosure used for the ISS EMU. This excitation would exist at the package interface.

(2) This environment envelops the maximum unattenuated flight launch shock and random vibration environments for Progress in orbital flight. This environment does not envelop the maximum flight shock environment for the Progress launch-escape system shock loads, nor does it envelop the maximum flight launch shock environment for Dragon shock loads.

(3) Criteria are the same for all directions (X, Y, Z).

(4) Qualification and Acceptance test margins are described in SSP 41172, ISSP Qualification and

Acceptance Environmental Test Requirements.

(5) A separate shock test is not required when the end item is tested to the equivalent damage potential random vibration environment defined in Table 3-9.

(6) Equivalent shock environments were determined using the methodology from TR-2004(8583)-1, Test Requirements for Launch, Upper Stage, and Space Vehicles, Paragraph 10.2.6, Threshold

Response Spectrum for Shock Significance.

(7) Dragon is excluded because the shock levels are too high to perform an equivalent random vibration damage potential test.

3.3.5 [R.FAN.100.012] DC MAGNETIC FIELD

The fan shall operate at all design points during and after exposure to a DC Magnetic Field of 250 Gauss as measured from 1 inch off the surface of the fan motor.

Rationale: This is considered a baseline capability that the suit must have to provide development freedom to vehicle systems. It is also characteristic of historical Shuttle/ISS EMU performance.

3.3.6 [R.FAN.100.013] SALT FOG

The fan, as packaged for flight, shall operate at all design points after exposure to a salt-fog environment, as defined by MIL-STD-810G, Method 509.6, with a NaCl concentration of 1% by weight for 30 days.

Rationale: The xPLSS and components must be capable of being shipped and handled in coastal regions, such as the Kennedy Space Center (KSC), without compromising the mission.

3.3.7 [R.FAN.100.014] FUNGUS

The fan, as packaged for flight, shall operate at all design points after exposure to fungus, as defined in MIL-STD

810G, Method 508.7.

Rationale: The xPLSS and components must be capable of being handled in coastal regions, such as the KSC and

JSC, without compromising the mission. The test itself requires a 28-day dwell in specified elevated temperature and humidity conditions after doping with specified fungi. Tthere is no intention to expose the flight hardware to this environment, as it will only be exposed to either an air conditioned lab, vacuum chamber, or exploration environment such as Low Earth Orbit (LEO), Lunar, Mars, etc., all of which would not promote fungus growth.

3.3.8 [R. FAN.100.015] OZONE

The fan, as packaged for flight, shall meet all performance requirements, after exposure to environmental ozone, at concentrations of 3 to 6 parts per 100 million at sea level, to a maximum of 100 parts per 100 million during air transportation at an altitude of 35,000 feet, for up to 30 days total exposure duration.

Rationale: This provides flexibility with transportation of the fan and xPLSS.

3.3.9 [R.FAN.100.016] IONIZING RADIATION

The fan shall meet requirements while operating in an ionizing radiation environment, as defined in SSP 30512, Space

Station Ionizing Radiation Design Environment, by meeting the Linear Energy Transfer (LET) and Total Ionizing

Dose (TID) requirements listed in Error! Reference source not found..

Table 3-10 – Ionizing Radiation Dosage

Component Non-Destructive SEE/SEFI(2)

Rates

Destructive SEE(3)

(MeV-cm2/mg)

Total Dose

Rad (Si)(1)

Fan < 10-2/2000 hrs > 36 10000

Rationale: The radiation environment is provided in two phases: one that addresses a more benign environment in

LEO that may allow for the use of Complementary Metal-Oxide-Semiconductor (CMOS) or enhanced

CMOS parts without the use of Rad-Hard by Design (RHD) parts, and one that addresses a much more stringent environment required for deep-space exploration, which will likely result in extensive use of

RHD components. The RHD components drive cost; schedule; and size, weight, and power (SWAP); as well as parts obsolescence issues, given the relatively small specialized market. Hence, it is efficient to design for the planned LEO usage with expectations of additional test or upgrades for operations beyond LEO using components that are available at that time.

(1) Assumptions for Total Ionizing Dose calculation

a. EVA duration = 8 hrs

b. Total life-time EVAs = 250

c. EVA on-orbit duration = 2000 hrs

d. IVA on-orbit duration = 10 years-2000hrs = 85600 hrs

Rationale: Components or surfaces that are nominally exposed to vacuum should not lose a significant amount of mass, if they are to retain their function over time. Mission-specific requirements, such as a Hubble

Servicing mission, will further restrict allowable volatile condensable materials.

3.6.10 [R.FAN.400.010] WELDING

The fan shall comply with NASA-STD-5006A, General Welding Requirements for Aerospace Materials, for all welding.

Rationale: Welding is not an expected manufacturing technique for the fan design currently envisioned. However, if welding is necessary, it needs to comply with the NASA standard above.

3.6.11 [R.FAN.400.011] FRAGMENT CONTAINMENT

The fan shall contain all fragments in the case of breakage of any frangible materials contained in the assembly.

Rationale: The intent of this requirement is to design the fan such that a blade failure of the fan would not result in puncturing the volute if the fan blade shed material. This also applies to items inside the motor housing.

3.6.12 [R.FAN.400.012] GENERAL WORKMANSHIP

The fan shall adhere to NASA-STD-8739.6, Implementation Requirements for NASA Workmanship Standards.

Rationale: This is standard practice for NASA spaceflight hardware.

3.6.13 [R.FAN.400.013] CRIMPING, INTERCONNECTING CABLES, HARNESSES, AND WIRING

The fan cables and harness shall comply with NASA-STD-8739.4, Workmanship Standard for Crimping, Interconnecting Cables, Harnesses, and Wiring.

Rationale: This is standard practice for NASA spaceflight hardware.

3.6.14 [R.FAN.400.014] SOLDERED ELECTRICAL AND ELECTRONIC ASSEMBLIES

The fan soldered electrical and electronic components shall adhere to IPC J-STD-001GS, Space and Military

Applications Electronic Hardware Addendum to J-STD-001G, Requirements for Soldered Electrical and Electronic

Assemblies, with the exception of Chapter 10 (Coating, Encapsulation, Staking and Bonding).

Rationale: Adopted from CTSD-ADV-780, Development Spec for the AEMU PLSS.

3.6.15 [R.FAN.400.015] ELECTROSTATIC DISCHARGE DESIGN

The fan shall meet Class 3A or better across the case or any external pin when tested in an unpowered state per MIL

STD-750-1A, DOD Test Method Standard: Environmental Test Methods for Semiconductor Devices, Part 1, Method

1020.5 Electrostatic Discharge Sensitivity (ESD) Classification. If the component does not achieve the “insensitive” classification, it shall be labeled per MIL-STD-1686C, DOD Standard Practice: Electrostatic Discharge Control

Program for Protection of Electrical and Electronic Parts, Assemblies and Equipment, in a clearly visible location.

Rationale: This assumes the Human Body Model (HBM) and is necessary given charges that may be accumulated during ground processing and handling. It is assumed that the system being maintained is unpowered and the crew will be wearing a ground strap when doing the work, but because they will not be able to verify the ground connection, this protection is necessary. Class 3A or better meets the ISS requirements stating that no damage will occur below 4000V.

3.6.16 [R.FAN.400.016] ELECTROSTATIC DISCHARGE PROTECTION

The fan shall comply with ANSI/ESD S20.20-2014, Protection of Electrical and Electronic Parts, Assemblies, and

Equipment.

Rationale: Adopted from CTSD-ADV-780, Development Spec for the AEMU PLSS.

3.6.17 [R.FAN.400.017] CORROSION CONTROL

replacement of a single fan is a real possibility. Preventing sharp edges will also benefit initial assembly and ground maintenance.

3.6.19 [R.FAN.400.019] FASTENER DESIGN

The fan shall implement fastener design in accordance with NASA-STD-5020, Requirements for Threaded Fastening

Systems in Spaceflight Hardware.

Rationale: Implementing fasteners that meet the requirements of NASA-STD-5020 will help increase the safety and reliability of the fan design.

3.6.20 [R.FAN.400.020] FASTENER INTEGRITY

The fan shall implement fastener integrity verification in accordance with NASA-STD-6008, NASA Fastener

Procurement, Receiving Inspection, and Storage Practices for Spaceflight Hardware.

Rationale: This ensures that quality fasteners are used in the design.

3.6.21 [R.FAN.400.021] GROUNDING

The fan shall electrically isolate the motor windings from the chassis.

Rationale: Electrically parallel components can provide conductive paths between flight elements, systems, subsystems, and equipment. The parallel conductive paths may provide the opportunity for ground loops and spurious common impedance sources for noise coupling. Noise represents a varying, uncontrolled, and detrimental contribution to the performance of electrical, electronic, and electromechanical equipment. Grounding is designed to preclude the environmental effects that can cause potential differences. Isolating the windings from the chassis will help prevent shock hazards.

This will satisfy the grounding requirements in SSP 30240, Space Station Grounding Requirements.

3.6.22 [R.FAN.400.022] ELECTRONIC, ELECTRICAL, AND ELECTROMECHANICAL (EEE) PARTS

The fan shall implement a design using electronic, electrical, and electromechanical (EEE) parts from the NASA Parts

Selection List (NPSL) or SSP 30423, Space Station Approved Electrical, Electronic, and Electromechanical (EEE)

Parts List, or obtain approval to use a non-EEE part via an Irregular Parts Approval Request (IPAR).

Rationale: This will help ensure that parts used in the design have proven supply chains.

3.6.23 [R.FAN.400.023] PARTS DERATING

The fan shall be designed with electrical and thermal derating as defined in SSP 30312, Electrical, Electronic, and

Electromechanical (EEE) Parts Management and Implementation Plan for the Space Station Program.

Rationale: The xEMU Project has not yet defined an EEE parts plan, but it is expected that using already-approved hardware will be more cost effective where added capability, reduced SWAP, or other advantages do not necessitate selection of unapproved parts that carry risk and cost burden.

3.6.24 [R.FAN.400.024] DESTRUCTIVE PHYSICAL ANALYSIS (DPA)

The fan, for flight production, shall screen all non-approved or Grade 2 EEE parts per MIL-STD-1580, DOD Test

Method Standard: Destructive Physical Analysis for Electronic, Electromagnetic, and Electromechanical Parts.

Rationale: This is intended to enable increased reliability of the components used in the fan by physically screening parts that do not have proven supply chains.

3.6.25 [R.FAN.400.025] FRACTURE CONTROL

The fan shall comply with SSP 30558, Fracture Control Requirements for Space Station.

Rationale: Because the fan is primarily metallic, and is part of a pressurized system, it needs to be evaluated under

SSP 30558. Per paragraph 4.4.2.1 of SSP 30558, the fan will be considered a Fracture Critical pressure system component because loss of pressurization would result in a catastrophic hazard. Proof testing the fan per the factor of safety requirements in SSP 30559, ISS Structural Design and

Verification Requirements, Section 3.3, will eliminate the requirement to perform a safe-life analysis.

3.7 INTERFACE CONTROL

3.7.1 [R.FAN.500.001] INTERFACE CONTROL DOCUMENT

The fan shall interface with the xPLSS assembly per Specification Control Drawing SLN13103091, PLSS Fan

323/324.

Rationale: This drawing defines the mechanical and electrical interfaces of the fan with the xPLSS assembly. As currently envisioned, the fan inlet attaches to the inlet manifold, and the fan outlet attaches to a check valve. Electrical wires terminate in a Glenair Mighty Mouse 805 series connector.

Fan Requirement Title Method Responsible for

Verification

Reference Notes

I A T D Vendor NASA

[R.FAN.000.019] Stator Temperature Sensor X X

[R.FAN.000.020] Stator Temperature Sensor

Excitation

X X

[R.FAN.000.021] Stator Temperature Accuracy and Range

X X

[R.FAN.000.022] Hall Effect Device (HED) X X

[R.FAN.000.023] Hall Effect Excitation X X

[R.FAN.000.024] Mass X X

[R.FAN.100.001] Ambient Pressure – Operational

[R.FAN.100.002] Ambient Pressure – Non-

Operational

[R.FAN.100.003] Ambient Pressure Rate

Decreasing – Operational

[R.FAN.100.004] Ambient Pressure Rate

Decreasing – Non-Operational

[R.FAN.100.005] Ambient Pressure Rate

Increasing – Operational

[R.FAN.100.006] Environmental Temperature

Profile

[R.FAN.100.007] External Humidity

[R.FAN.100.008] Acceleration – Launch

Vehicles

[R.FAN.100.009] Acceleration – Survivable

[R.FAN.100.010] Random Vibration – Operating

[R.FAN.100.011]…