11 June 2002 Meeting Minutes for
Space Systems - Dependability Data Transfer Formats Standard
Working Group
Primary Objective
The primary objective of this working group is to develop a commercial standard
that provides a single framework for transferring data between tools and the Reliability,
Maintainability, and Availability (RMA) database that is necessary to achieve high RMA
requirements for space systems. The Extensible Machine Language (XML) shall be
used to define the standard transport formats for data that are described in the
standard. The title of the standard may have to be changed to, “Space Systems Dependability Data Transfer Formats Standard,” in order for it to be published as an
AIAA standard. The draft standard is scheduled for completion by 30 September 2002.
To achieve the primary objective of the WG required dividing the WG into two
teams. Team 1 consists of reliability analysts and Team 2 consists of tool developers.
The Team 1 lead is Tyrone Jackson and the Team 2 lead is Dan Hartop. Team 1 is
tasked with (1) defining the data that are critical to the development of a high-reliability
space system, and (2) showing why the data is critical by defining the functions in the
Systems Engineering Process that use and generate the data. Team 2 is tasked with
defining the XML formats for the data.
11 June 2002 Meeting
The 6th meeting of the Space Systems - Dependability Data Transfer Formats
Standard WG was held on Tuesday, June 11, 2002, from 8:30 AM to 10:30 AM PDT.
The meeting consisted of a teleconference that was mediated by Tyrone Jackson at
The Aerospace Corporation in El Segundo, CA. The meeting agenda is on page 3.
Participants at the June 11th meeting were:
NAME
Tyrone Jackson(1)
Dan Hartop(2)
Jim Sketoe
Steve Harbater
Al Jackson
Terry Kinney
Robert Poltz
Xuegao (David)
Walt Willing
Kamran Nouri
(1)
(2)
COMPANY
Aerospace Corp.
DSI Intl.
Boeing
TRW
CSULB Eng Grad College
Spectrum Astro
Design Analytx
SoHar Inc.
Northrop Grumman
Item Software
PHONE
310-336-6170
714-637-9325
253-773-2891
858-592-3490
310-493-7469
719-550-0325
877-327-7550
323-653-4717
410-765-7372
714-935-2900
Meeting coordinator and Team 1 lead
Team 2 lead
1
E-MAIL
Tyrone.Jackson@aero.org
dhartop@dsiintl.com
James.E.Sketoe@boeing.com
Steve.Harbater@trw.com
jacksona@simanima.com
Terry.Kinney@specastro.com
getreliability@designanalytx.com
Xuegao@sohar.com
walter_e_willing@md.northgrum.com
kamran@itemsoft.com
The following individuals are on regular distribution for the SSRT Standards WG
Meeting minutes:
NAME
Mike Canga
James Womack
John Ingram-Cotton
Dave Dylis
Eric Gould
Jim Kallis
Bill Geimer
Leo F. Watkins
Marios Savva
Adamantios Mettas
Doug Ogden
Rich Pugh
Ken Murphy
Myron Hecht
Rebecca Menes
Bob Miller
Halil Kilic
Kevin P. Van Fleet
Hunter Shaw
Clarence Meese
Craig Day
James French
Rus Vacante
COMPANY
NASA JSC
Aerospace Corp.
Aerospace Corp.
RAC
DSI Intl.
Raytheon
Northrop Grumman
Lockheed Martin
Reliasoft
ReliaSoft
ReliaSoft
Pratt Whitney
ARINC
Sohar Inc.
Sohar Inc.
TRW
TRW
Relex Software
Relex Software
SRE
AIAA
AIAA
RMA Partnership
PHONE
281-483-5395
310-336-7647
310-336-1249
315-339-7055
714-637-9325
310-647-3620
626-812-2783
817-935-4452
520-886-0410
520-886-0366 Ext. 29
520-886-0366 Ext. 41
505-248-0640
323-653-4717X111
323-653-4717X101
310-812-2840
310-814-1998
724-836-8800 x105
724-836-8800
703-264-3849
703-264-7570
703-805-4864
2
E-MAIL
michael.a.canga1@jsc.nasa.gov
James.M.Womack@aero.org
John.Ingram-Cotton@aero.org
DDylis@IITRI.ORG
egould@dsiintl.com
jmkallis@west.raytheon.com
William.Geimer@northropgrumman.com
Leo.F.Watkins@LMCO.com
Marios.Savva@reliasoft.com
Adamantios.Mettas@ReliaSoft.com
Doug.Ogden@ReliaSoft.com
pugh@pwfl.com
KMURPHY@arinc.com
Myron@sohar.com
Becky@sohar.com
Robert.Miller@trw.com
ha.kilic@trw.com
kevin.vanfleet@relexsoftware.com
Hunter.Shaw@relexsoftware.com
cmeese@nyx.net
craigd@aiaa.org
jimf@aiaa.org
russv@erols.com
June 11th Meeting Agenda
Time
Working Group Administrative Topics
8:30 - 8:45 PDT
Take roll
Vote to approve the minutes for the April 30th, May 14th, and May
28th meetings
Vote to approve proposal for AIAA to sponsor draft standard
Time
Team 1 & 2 Joint Discussion Topics
8:45 - 9:15 PDT
Discuss WG comments on Fault Tree schema
9:15 - 9:30 PDT
Identify leads for the other schemas that must be written
9:30 - 10:00 PDT
Discuss Section 6, Reliability Analysis Data Models
10:00 - 10:15 PDT Identify leads for the other sections that must be written
10:15 - 10:30 PDT Break
Time
Team 1 & 2 Separate Discussion Topics
10:30 - 11:30 PDT Teams conduct open discussions using separate teleconferences
11:30 PDT
Meeting adjourn
3
Team 1 & Team 2 Joint Discussion Topics

Team 1 participants in the June 11th meeting were:






Steve Harbater
Tyrone Jackson (Team 1 Lead)
Terry Kinney
Rob Poltz
Jim Sketeo
Walt Willing

Team 1 meet the minimum number of participants required for a Team 1
quorum, and voted to approve the meeting minutes for April 30 th, May 14th, and
May 28th.

Team 2 participants in the June 11th meeting were:




Dan Hartop (Team 2 Lead)
Al Jackson
Kamran Nouri
David Xuegao

As a result of a group discussion about the potential benefits of a set of standard
names for equipment that is common to generic categories of space systems,
the wording for problem #1 was revised in the list of the “Top-10 Space Systems
Reliability Program Problems” (see page 7).

The original goal of the WG was to produce a Society of Reliability Engineers
(SRE) Standard. However, since the SRE does not have an established process
for publishing standards, the WG decided to submit a Standard Project Proposal
to the American Institute of Aeronautics and Astronautics (AIAA) Standards
Executive Council for approval consideration in August 2002.

As a result of the WG reviewing the updated Fault Tree Schema that Team 2
constructed, it was decided that Fault Tree Analysis is best used as a selective
tool for enhancing the fidelity of FMECA. Therefore, a FMECA Schema needs to
be included in the standard. Tyrone volunteered to write a FMECA Schema that
shows the conditions under which Fault Tree Analysis should be performed.

The WG finalized the outline for the draft standard (see final outline on page 9).

At least two members of the WG volunteered to write each section of the draft
standard (see names of section writers on page 9).

After the meeting, Tyrone e-mailed the AIAA Standard Project Proposal to Bob
French. Bob suggested that the title of the draft standard be changed to, "Space
Systems - Dependability Data Transfer Formats Standard," or something like
that. It seems that in the international community, "Dependability" includes all of
4
the "ilities" that are covered in the outline of the draft standard. The WG will vote
on whether to change the name of the draft standard at the next meeting on
June 25th. Bob also suggested that all future reviews of the draft standard be
limited to within the WG. Lastly, if the WG commits to writing an AIAA standard,
then it will inevitably lead to more work because each writer will have to follow
the AIAA writing style guide.
Action Items
1. Team 1 and Team 2 Action Items –
a. Tyrone – Write a FMECA Schema
b. All – Begin writing the sections of the draft standard
Next Meeting
The next SSRT Standards WG Meeting is scheduled for June 25, 2002, from 9:30 AM
PDT to 11:30 AM. Both Team 1 and Team 2 are to call the following teleconference
number:

Teleconference number - (888) 550-5969, pass code 646354
Arrangements have been made for the WG to use NetMeeting concurrently during
the teleconference. For those that prefer face-to-face discussions, meeting rooms have
been reserved at the following locations:

Team 1 meeting room - The Aerospace Corporation, Building D-8, 200 N.
Aviation Boulevard, El Segundo, CA 90245-4691

Team 2 meeting room - DSI International, 1574 N. Batavia, Suite 3, Orange, CA
92867
5
Planned Future Meetings
Location:
The Aerospace Corporation, Building D-8, 200 N. Aviation
Boulevard, El Segundo, CA 90245-4691
Date:
2002
6/25
Teleconference
7/16
Teleconference
7/30
Teleconference
8/13
Teleconference
8/27
Teleconference
9/10
Teleconference
9/24
Teleconference
Please direct all comments regarding these meeting minutes to:
Tyrone Jackson
Space Systems - Dependability Data Transfer Formats Standard Working Group
Coordinator
Tyrone Jackson
Reliability & Statistics Office
The Aerospace Corporation
Ph. (310) 336-6170
Fax (310) 336-5365
Email: Tyrone.Jackson@aero.org
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Top-10 Space Systems Reliability Program Problems1
1. Valuable RMA lessons learned often are not in a format that is readily assessable or
useable by the Reliability Program, or they have become “lessons lost” in an overwhelming mass of engineering information. For example, a useful lesson learned might
never be linked to the equipment that it applies if the name that is used to search for
information is different than the name recorded in the database.
2. Some reliability critical items often are not identified at all or are not properly
controlled.
3. System reliability predictions often do not include probability of occurrence estimates
for all relevant failure modes, failure mechanisms, and failure causes. (Probability of
induced faults during manufacture or probability of damage during assembly usually is
not included in reliability predictions.)
4. The perceived accuracy of high-reliability predictions and dependability/availability
predictions often is not supported by (1) input data that is less precise than the result, or
(2) equations that are misapplied or incorrect.
5. The number of job openings for reliability analysts is steadily decreasing, and as a
result, the number of filled positions is insufficient to adequately support an increasing
number of space system development projects. This situation often has lead to
reliability assessment methods being improperly applied, untimely, or not cost-effective.
6. Many commercial reliability assessment tools have major shortcomings that may not
be obvious to the casual reliability analyst (e.g., inaccurate equipment failure rate
models, unverifiable parameters in equations, high misapplication rates, etc.).
7. Often, insufficient funding is provided to perform all of the tasks necessary for a HighReliability Program. (Some customers and managers believe that high-reliability can be
tested-in more cost-effectively than it can be designed-in.)
8. Different approaches are being used across the space industry to perform reliability
assessment tasks that are called by the same name, but which often serve different
purposes. (Inconsistency in reliability assessment practices has become a major
problem since DoD canceled military standards in the mid 90’s.)
9. Some customers’ believe that all dependability/availability predictions for space
vehicle constellations are too conservative. (The basis of this belief is rooted in
historical evidence that shows contingency procedures of ground operations are very
effective for extending the useful life of a space vehicle far beyond it’s predicted meanlife. This phenomenon has resulted in many customers buying more space vehicles
than necessary to meet the dependability requirements of the constellation.)
10. Often it is difficult for an organization to assure that the latest versions of the
reliability assessment models match the latest configuration of the space system
1
This list of top-10 problems was determined by an internal working group survey.
7
design. Part of this problem is because reliability assessment tools generally do not
label every element in the model with the date and time its was created.
8
Final Outline (06-11-02)
Space Systems - Dependability Data Transfer Formats Standard
Table of Contents
Section 1 – Introduction (Tyrone)
1.1 General
1.2 Scope
1.3 Purpose
1.4 Reference Documents
1.5 Definitions
1.6 General Requirements for Interchanging Data with a RMA Database
Section 2 – RMA Requirements Data - Data Transfer Format A (Terry and Tyrone)
Section 3 – Functional Data Models - Data Transfer Format B (Dan and Kamran)
Section 4 – Physical Data Models - Data Transfer Format C (Tyrone is to ask RAC and NASA for input)
Section 5 – Stress Parameters Data Models - Data Transfer Format D (Jim, Steve, and Walt)
Section 6 – Reliability Analysis/FMECA Data Models - Data Transfer Format E
6.1 – Reliability Analysis Data Models - Data Transfer Format E1 (Kamran, David, and Al)
6.2 – FMECA Data Models - Data Transfer Format E2 (Rob and Tyrone)
Section 7 – Maintainability/Failure Analysis Data Models - Data Transfer Format F
7.1 – Maintainability Analysis Data Models - Data Transfer Format F1 (Jim and Rob)
7.2 – Failure Analysis Data Models - Data Transfer Format F2 (Rob and Tyrone)
Section 8 – Dependability and Availability Analysis Data Models - Data Transfer Format G
8.1 – Dependability Analysis Data Models - Data Transfer Format G1 (Terry and Walt)
8.2 – Availability Analysis Data Models - Data Transfer Format G2 (Terry and Walt)
Section 9 – Similar System/Component Experience Data - Data Transfer Format H
9.1 – RMA Design Concerns & Rules - Data Transfer Format H1 (Steve and Tyrone)
9.2 – Sneak Clues - Data Transfer Format H2 (Steve and Tyrone)
Appendix A – Space Systems Life Cycle Reliability Process Guide (Tyrone)
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Reliability, Maintainability & Availability Assessment Model Flow
Format B
Requirements to
Functional Model
Mapping
2.4.2
Format A
System &
Subsystem RMA
Reqs. Data
2.4.1
Format C
Functional to
Physical Model
Mapping
2.4.2, 2.4.4, 2.4.5,
2.4.6
Format D
Functional &
Physical to Stress
Parameters Model
Mapping
2.4.9
Format E
Format H
Functional, Physical, Stress
Parameters & Maintainability/
Failure Analysis to Reliability
Analysis/FMECA Model
Mapping
2.4.7, 2.4.8, 2.4.9, 2.4.10
Format F
Similar System/
Component
Experience Data
2.4.3
Functional, Physical, Stress
Parameters & Reliability
Analysis/FMECA to
Maintainability/Failure
Analysis Model Mapping
2.4.10
Format G
DATA TRANSFER FORMATS:
A - RMA Requirements Data
B - Functional Models
C - Physical Models
Test & Field Failure Data
F - Maintainability/Failure Analysis Models
F1 - Maintainability Analysis Models
F2 - Failure Analysis Models
D - Stress Parameters Models
G - Dependability/Availability Analysis Models
G1 - Dependability Analysis Models
G2 - Availability Analysis Models
E - Reliability Analysis/FMECA Models
E1 - Reliability Analysis Models
E2 - FMECA Models
H - Similar System/Component Experience Data
H1 - RMA Design Concerns & Rules
H2 - Sneak Clues
10
Reliability Analysis/FMECA
& Maintainability/Failure
Analysis to Dependability/
Availability Model Mapping
2.4.10