Air Safety Through Investigation - Journal of the International Society of Air Safety Investigators - ISASI
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Air Safety Through Investigation OCTOBER-DECEMBER 2017 Journal of the International Society of Air Safety Investigators Extending the Network and Using Available Resources—page 4 Collaborative Component Examinations—page 10 What Makes a Good Air Safety Recommendation?—page 15 Linkages Between Occurrences and Safety System Performance—page 18 Safety Recommendations: Strengthening EASA’s SRM Process—page 24
CONTENTS Air Safety Through Investigation
Journal of the International Society of Air Safety Investigators
Volume 50, Number 4
Publisher Frank Del Gandio
Editorial Advisor Richard B. Stone
Editor J. Gary DiNunno
Design Editor Jesica Ferry
Associate Editor Susan Fager
ISASI Forum (ISSN 1088-8128) is published quar-
FEATURES terly by the International Society of Air Safety
Investigators. Opinions expressed by authors do
not necessarily represent official ISASI position
4 Extending the Network and Using Available Resources or policy.
By Michael Guan, Ph.D.; Brian C. Kuo, Ph.D.; and Yann Torres—The authors, using two
Editorial Offices: Park Center, 107 East Holly
aircraft accidents as examples, examine how a small investigative agency can successfully Avenue, Suite 11, Sterling, VA 20164-5405. Tele-
determine causal factors and recommend air safety improvements. phone 703-430-9668. Fax 703-430-4970. E-mail
address, isasi@erols.com; for editor, espmart@
10 Collaborative Component Examinations comcast.net. Internet website: www.isasi.org.
By Eric J. East, Air Safety Investigator, Boeing Commercial Airplanes—The author ob- ISASI Forum is not responsible for unsolicited
serves that one of the key links in the process for determining probable cause of an aircraft manuscripts, photographs, or other materials.
accident is the physical examination, interpretation, and relevance of hardware and data Unsolicited materials will be returned only if
that are recovered from an incident or accident site. submitted with a self-addressed, stamped enve-
lope. ISASI Forum reserves the right to reject,
15 What Makes a Good Air Safety Recommendation? delete, summarize, or edit for space con-
By Maria Gregson, Faculty of Engineering, University of Nottingham, UK—The author is siderations any submitted article. To facilitate
one of ISASI’s four Kapustin scholarship winners for 2017. She presented her winning essay editorial production processes, American Eng-
lish spelling of words is used.
during ISASI’s 2017 seminar.
Copyright © 2017—International Society of Air
18 Linkages Between Occurrences and Safety System Performance Safety Investigators, all rights reserved. Publica-
By Heather Fitzpatrick, Senior Transport Safety Investigator, Australian Transport Safety tion in any form is prohibited without permis-
Bureau—The author details the utility of the Australian Transport Safety Bureau’s fatigue and sion. ISASI Forum registered U.S. Patent and
fatigue risk management system in establishing a tangible link between the performance of an T.M. Office. Opinions expressed by authors do
organization’s systems and an occurrence event. not necessarily represent official ISASI position
or policy. Permission to reprint is available upon
24 Safety Recommendations: Strengthening EASA’s SRM Process application to the editorial offices.
By Mario Colavita, Safety Investigation Officer, European Aviation Safety Agency—The
author describes the existing link between the European Aviation Safety Agency’s safety risk Publisher’s Editorial Profile: ISASI Forum is print-
ed in the United States and published for profes-
management process and the use of safety recommendations as a key element for the identifi-
sional air safety investigators who are members
cation of the systemic safety issues and their prioritization. of the International Society of Air Safety Inves-
tigators. Editorial content emphasizes accident
investigation findings, investigative techniques
DEPARTMENTS
and experiences, regulatory issues, industry ac-
cident prevention developments, and ISASI and
member involvement and information.
2 Contents
3 President’s View—Air Safety Investigators Make a Positive Difference Subscriptions: A subscription to members is pro-
vided as a portion of dues. Rate for nonmem-
28 News Roundup bers (domestic and Canada) is US$28; Rate for
30 ISASI Information nonmember international is US$30. Rate for all
32 International Council Meets in San Diego libraries and schools is US$24. For subscription
information, call 703-430-9668. Additional or
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ABOUT THE COVER tional nonmember US$8.
A TransAsia Airways ATR 72 experienced a loss of control during initial climb
from Taipei’s Songshan Airport on February 4, 2015 and crashed into the Keel-
ing River resulting in 43 fatalities and injuries to surviving passengers, a flight
crew member, a taxi driver and his passenger. (See “Extending the Network and
INCORPORATED AUGUST 31, 1964
Using Available Resources”, page 4.)
2 • October-December 2017 ISASI ForumPRESIDENT’S VIEW
AIR SAFETY INVESTIGATORS MAKE A POSITIVE DIFFERENCE
W
e recently completed a very rome Lederer Award for his leadership and investigate accidents and incidences.
successful ISASI seminar in San extraordinary efforts to enhance air safety • Develop positive working relationships
Diego, California, during which investigation in Singapore and to encour- among the various aviation agencies,
more than 360 delegates and age international air safety cooperation corporations, and organizations that
companions participated in three days of well beyond the Asian region. An article on affect air safety—the interested parties
technical presentations and heard perti- the seminar will appear in the next issue of that converge on an accident investiga-
nent keynote addresses from U.S. National ISASI Forum. tion—prior to getting the phone call to
Transportation Safety Board Chairman The theme of this year’s gathering asked go to the site.
Robert Sumwalt (a longtime ISASI member) the question does air safety investigation • Talk to family and community mem-
and James Viola (also an ISASI member), make a difference? As I have said many bers about the positive aspects of our
head of the U.S. Federal Aviation Adminis- times, ISASI members all know the correct work.
tration’s Office of General Aviation Safety answer to this question. However, what
• Share our experiences and expertise
Assurance. Participants had an opportu- we actually accomplish can get lost in the
with young people who’ve recently
nity to meet and share experiences with fog of day-to-day responsibilities, regula- begun their air safety careers or who
colleagues from 35 countries and visit local tions, paperwork, and when that inevitable are studying to do so in the future. They
sites of interest. phone call arrives demanding our imme- want and need to hear from those of us
Two tutorials preceded the seminar. diate presence at yet another air accident who’ve been longtime investigators and
safety advocates. Becoming an ISASI
AN AIR SAFETY INVESTIGATOR’S JOB IS COMPLICATED AND student mentor often has as many ben-
DIFFICULT. WE ALL KNOW THIS TOO, BUT HOW WE RESPOND efits for us as it does for the students
with whom we interact.
TO THIS DIFFICULTY CAN MAKE THE DIFFERENCE BETWEEN
• Identify our personal support sys-
HAVING A SUSTAINABLE, LONG-TERM CAREER OR AN EARLY tems—people who can help us stay
BURNOUT. on track when we start to lose sight of
our priorities or our best path to stable
Nearly 50 military participants attended an in some hard-to-reach or even dangerous physical or mental health.
all-day session that took a look at how mil- location. An air safety investigator’s job is • Attend ISASI meetings and seminars
itary air accident investigators from many complicated and difficult. We all know this at the regional, state, or international
different countries do their job. Some 74 too, but how we respond to this difficulty levels with colleagues from different
civilian air accident investigators attended can make the difference between having agencies, countries, and cultures to
two half-day presentations: flight recorders a sustainable, long-term career or an early develop working relationships in a
beyond International Civil Aviation Or- burnout. friendly, supportive environment to
ganization Annex 13 and how air accident There are a number of ways to help clear enhance teamwork that will carry
survival factors help to lower fatal accident over to cooperation on some future
the fog.
rates and reduce injuries. investigation.
• Focus on how we do make a positive
Four Kapustin scholars presented difference in air safety. There are many reasons why air acci-
essays—one of which appears in this issue. dents have reduced in numbers and
• Realize our part in developing and fatalities in
The number of annual scholarships that
promoting the technical and procedur-
ISASI provides depends entirely on the recent years—
al changes brought about from safety
amount of donations from ISASI members. recommendations that have saved the professional-
More information about the scholarships— peoples’ lives. ism, expertise,
how to donate and how to apply—can be and commit-
• Remember that we’re not alone. The ment of ISASI
found on our website under the Awards
men and women who are ISASI mem- members to
tag. I hope you’ll continue to provide an
bers, the agencies that employ ISASI
opportunity for these exceptional students enhance all
members, the states that establish and
to attend our seminar and to find career fund these agencies, and the inter- aspects of air
opportunities in their respective aviation national organizations that establish safety, our
fields. safety guidelines for member states all efforts—are
The gathering culminated with the have the same ultimate goal—making among the most
annual awards dinner during which Chan, air travel safer and developing best effective of Frank Del Gandio
Wing Keong was recognized with the Je- practices for those of us who must those reasons. ISASI President
October-December 2017 ISASI Forum • 3EXTENDING THE NETWORK AND
sent to flight recorder manufacturers for
flight recorder training courses. The ASC
is also interested in on-job training (OJT)
USING AVAILABLE RESOURCES at accident investigation authorities
(AIAs).
Nowadays, in order to manage a short-
By Michael Guan, Ph.D.; Brian C. Kuo, Ph.D.; and Yann Torres age in the budget and extend the techni-
(Adapted with permission from the authors’ technical paper entitled Extend the Network and cal capabilities for future investigations,
Exploit Available Resources—Lessons Learned from Two Major Investigations presented during the ASC lab continues to seek different
ISASI 2016 in Reykjavik, Iceland. The full presentation can be found on the ISASI website at www. forms of technical collaborations with
isasi.org in the Library tab under Technical Presentations.—Editor) domestic agencies and foreign AIAs.
C
ompared to Australia, Europe, The ASC investigation lab has also been
and North America, aviation involved in several foreign investigations, Domestic collaboration
safety investigations and for which the ASC has appointed accred- The ASC signed memorandums of under-
safety studies in Taiwan began ited representatives. In order to build standing (MOUs) with seven domestic
relatively recently—about 20 years experience in flight recorder readout and (government) agencies, including the Civ-
ago. The Aviation Safety Council analysis, the ASC also provides technical il Aeronautics Administration (CAA), the
(ASC) was established in May 1998 as assistance to other agencies. In 2014, the Chinese Ocean and Underwater Technol-
an independent government agency lab completed seven CVR and 76 FDR/ ogy Association (COUTA), the Ministry
in Taiwan, the Republic of China, QAR readouts, seven animation sets, and of National Defense (MND), the Ministry
responsible for the investigation of 13 sets of GPS/radar data and satellite of Justice (MOJ), the National Airborne
civil, public, and ultra-light aircraft map superposition (see Table 1). Service Corps (NASC), the National Fire
accidents and serious incidents (Avi- Agency of the Ministry of the Interior
ation Occurrence Investigation Act 1, (NFA/MOI), and the Taoyuan Internation-
2), as well as safety recommendations Domestic and international al Airport Company (TIAC).
issuance directly to the premier and collaboration Based on those MOUs, the ASC
follow-up. Since its establishment, To continue fostering working part- maintains excellent collaboration with
the ASC has investigated 118 occur- nerships developed over the years with national judicial agencies and criminal
rences and issued 937 safety recom- domestic and international agencies and investigation units to perform necessary
mendations. sharing a common vision of improving air examinations (e.g., autopsy, DNA, and
The ASC investigation lab, with a staff safety by exchanging and analyzing safety medical). After training by ASC investiga-
of five, is in charge of providing technical data, the ASC believes that technical tors, CAA inspectors and TIAC technical
support to aviation occurrence investiga- cooperation is a key to link each agency staff are capable of following ASC’s SOP
tion. This includes, but is not limited to, to work together. Depending on available to assist in securing perishable evidence
site survey, flight recorder readout, flight resources, there are four kinds of interna- during occurrences before the ASC go-
path reconstruction, radar data and GPS tional technical collaboration, including team arrives at the occurrence site.
data processing, performance analysis, workshop/seminar, joint training/exer- The benefits of domestic bilateral
and visualization. The lab also under- cise, technical assistance, and occurrence agreements include sharing training
takes several safety studies and research investigation. resources, transportation, wreckage
programs, e.g., wet runway performance, For instance, pursuing knowledge on handling capabilities, and providing
locating black boxes under water, struc- flight recorder readout is a top priority technical support on sea crash accident
tural examination, and failure analysis. for the ASC; therefore, investigators were investigation.
International collaboration
In addition, the ASC has reached techni-
cal collaboration with 15 worldwide AIAs
and has signed seven MOUs with the UK
Air Accidents Investigation Branch (UK
AAIB), the Australian Transport Safety
Bureau (ATSB), the Bureau d’Enquêtes et
d’Analyses pour la sécurité de l’aviation
civile (BEA), the Japan Transport Safety
Board (JTSB), the Korean Aviation and
Railway Accident Investigation Board
(KARAIB), the U.S. National Transporta-
tion Safety Board (NTSB), and the Trans-
portation Safety Board of Canada (TSB).
In the last decade, ASC investigators
have learned techniques to process dam-
aged flight recorders and investigation
methodology from the ATSB, the BEA,
the NTSB, and the TSB. Based on OJT and
accident investigations in practice, ASC
Table 1. Summary of Flight Data Readouts investigators have adhered to Attachment
4 • October-December 2017 ISASI ForumD “guidelines for flight recorder read- Metallurgical Investigator Group.
out and analysis” of the International
Civil Aviation Organization’s (ICAO)
Annex 13, have maintained proper Technical cooperation between the
technical capabilities to support ASC ASC and the CIB
occurrence investigation, and have In May 2002, the ASC signed a MOU
assisted nearby AIAs in setting up with the MOJ Taiwan regarding avi- Dr. Michael Guan
their readout capabilities. ation occurrence investigation and
The benefits of international criminal investigation to establish a has been an air safety investigator for the
bilateral agreements include shar- coordination mechanism and share Aviation Safety Council (ASC) since 1998. He is
ing training resources, developing technical resources. For criminal currently the director of the investigation lab
and testing new tools, exchanging investigation in Taiwan, the MOJ relies at the ASC. He has a masters and Ph.D. in aer-
safety databases, and providing on the Criminal Investigation Bureau onautics and astronautics from Cheng-Kung
technical supports to ICAO Annex (CIB) and the MOI to examine evi- University in Taiwan. His primary role has
13 investigations. dence and provide technical findings been to investigate aircraft performance and
to assist MOJ prosecutors. Major tech- to read out flight recorders. He has participat-
nical capabilities of the CIB include ed in a number of international investigations,
Technical cooperation between DNA testing, examining dangerous including Singapore Airlines SQ006, China
the ASC and the BEA goods and weapons, victim identifica- Airlines CI611, and three TNA cases–GE791,
In May 2001, the ASC and the BEA tion, and ground survey tools. GE222, and GE235. He has also been actively
signed the “Guidelines for the Con- In any fatal aviation accident that involved in developing investigation tools at
duct of International Aviation Acci- occurs in Taiwan, the CIB plays a key the ASC.
dent Investigations” MOU. Based on role coordinating with the ASC and
the MOU, the BEA supported three the MOJ. The three agencies have
ASC recurrent trainings in 2003, 2007, shared training resources and per-
and 2009. BEA senior investigators formed joint exercises to improve on-
provided detailed technical coop- scene survey knowledge and analysis
eration protocols, sharing aviation skills for multidata sets. For example,
safety investigative skills and meth- the ASC assisted the CIB and the MOJ
odologies, helping the ASC to setup with a marine criminal investigation Dr. Brian C. Kuo
occurrence ECCAIRs, an occurrence in 2009 and 2013.
statistics tool, and a database. is an investigator and a flight recorder engi-
In addition, the ASC dispatched neer at the investigation lab at the Aviation
five investigators to the BEA labo- Technical research projects and Safety Council (ASC). He has participated in a
ratory for a one-week OJT. Topics exercises few international investigations—TNA GE 222
included damaged flight recorder There are two kinds of technical re- and GE235. Prior to joining the ASC in 2010, he
processing, audio spectrum analy- search projects at the ASC—self-study was a post-doctoral researcher in the Depart-
sis, and nonvolatile memory (NVM) safety projects and joint research ment of Mechanical and Aerospace Engineer-
readout. To develop closer coopera- projects. Typically, self-study safety ing, University of California, Davis, U.S.A.
tion, the BEA invited the ASC to join projects are executed by ASC inves-
two working groups during the Air tigators and include audio spectrum
France Flight 447 investigation. The analysis, an annual survey of flight
ASC provided flight data assistance recorder installation on national reg-
and worked with major AIAs on top- istered aircraft, investigating wet run-
ics ranging from underwater search way occurrences related to suspected
to flight data transmission during a hydroplaning, ECCAIRS, and HFACS
distress scenario. coding application. Yann Torres
In 2004, flight recorder specialists The Execute Yuan or the Ministry
from major investigation labora- of Science and Technology (MOST) has been an air safety investigator for the Bu-
tories held an accident investigators fund these joint research projects. reau d’Enquêtes et d’Analyses pour la sécurité
in recorder (AIR) technical meet- ASC board members review safety de l’aviation civile since 1998. He is currently
ing in Italy. In 2005, the ASC helped statistical data, prioritize relevant director of investigation, head of the southern
AIAs establish and then maintain a safety study topics, and encourage regional office (Toulouse). He has an aero-
security portal for AIR members. The ASC investigators to invite academ- nautical engineering degree from the Ecole
website was called the International ic researchers to join these specific Nationale de l’Aviation Civile in France. His
Recorder Investigator Group (IRIG). topics. Two big projects were finished primary role has been to perform safety inves-
The IRIG contains technical papers in 2009 and 2010. There are another tigations acting as the investigator-in-charge
from the annual AIR meetings as well two projects in the works. The major over the French territory and acting as the
as several technical forums to discuss objectives of joint research projects, accredited representative of several major
CVR, FDR, and video and NVM chip based on the lessons learned from accidents overseas. He also acted as the
recovery issues. In 2015, the IRIG ECCAIRS and HFACS coding, adopt aircraft performance and system group leader
extended its technical link from flight ATSB safety analysis methodology into in several major international investigations,
recorders to aircraft structure and ASC investigation procedures, which including Air France Concorde, Qantas QF32,
metallurgical materials. This sister aim to improve general aviation safety and different ATR major cases such as TNA
website was called the International in Taiwan and evaluate lightweight GE791, GE222, and GE235.
October-December 2017 ISASI Forum • 5water recovery of flight recorders in May
2010. The ASC invited the Coast Guard,
the Hong Kong Civil Aviation Depart-
ment, the KARAIB, and the Singapore
AAIB to join this activity. Some of the
attendees took the lessons learned from
this sea search exercise and helped the
KARAIB perform the sea search mis-
sion of Asiana Airlines Flight 991, which
crashed into the East Sea on July 28, 2011.
Based on MOUs, the ASC can use rele-
vant resources from the Coast Guard, the
COUTA, and the MND to execute a sea
search and locate the black box.
Development of UAV-based aerial
mapping system
In 2004, the ASC began evaluating the
use of light RPV or UAV in investigations.
The ASC determined that RPVs and UAVs
Figure 1. Statistics of civil fixed-wing and rotary-wing aircraft. would not be used for long endurance
search and rescue but for wreckage
recorder feasibility. respectively. The number of civil distributed over a wide area or in rugged
The theme of ISASI 2016 was “Every aircraft with tape-based CVRs and terrain to gather aerial images of the
Link Is Important.” This paper highlights FDRs are 0% and 0.4%, respectively. wreckage and generate high-resolution
the bilateral benefits in four areas: the an- The number of the civil aircraft photos.
nual survey of flight recorder installation, with 30-minute CVRs and 120-min- In 2005, the ASC purchased a first-gen-
the joint exercise for the sea search and ute CVRs are 8.5% and 85.8%, eration RPV. Due to several operational
recovery of black boxes, the development respectively. experiences and lessons learned from the
of UAV-based aerial mapping systems for • The number of civil aircraft with an ASC/CIB joint exercise on ground vehicle
aviation occurrence investigation, and FDR readout database in paper and explosions, the ASC decided in 2010 to
industrial cooperation on flight recorder an electronic file is 52.5% and 72.5%, acquire a second-generation UAV.
readout and analysis. Regarding these respectively. Between 2011 and 2014, the ASC con-
efforts, the authors will present factors ducted more than 10 exercises to improve
from two major investigations to demon- • The number of FDR readout databas-
its own UAV operational skills, develop
strate how the ASC adheres to ICAO es with verification is 93.3%.
SOPs, review the evaluation guide to
Annex 13 protocol and collaborates with • The number of the civil aircraft with site hazards, standardize mission plans
AIAs, aircraft manufacturers, judicial QARs is 85.4%. and flight routes, develop an in-house
agencies, and airline operators. program to improve the quality of aerial
After checking, accepting, and review-
ing the training progress, by the end of mapping, generate precise terrain infor-
mation, and integrate the information
Annual survey of flight recorder instal- 2015 the ASC readout capability for the
into a flight animation system.
lation on national registered aircraft surveyed CVRs and FDRs was 99.6%
and 99.6%, respectively. The ASC deter- The ASC presented its technical paper
The ASC carries out a routine survey of “UAV Aerial Photography on Debris Map-
flight recorder installation for nation- mined that only one recorder from a new
Gulfstream G280 did not have its own ping” in the second AsiaSASI meeting in
al registered aircraft. The goal of this Taipei in 2013 to pursue better solutions
survey is to review the installation of download equipment.
for UAV mapping and deepen the techni-
CVRs, FDRs, FDAUs, and QARs at various cal cooperation with AIAs of the Asia-Pa-
national operators. The findings are the cific region. The ASC also provided a UAV
basis for enhancing the readout capability Joint exercise for sea search and demonstration flight to simulate applica-
of the investigation laboratory and flight black box recovery tion tips for occurrence investigation.
recorder readout in relation to occur- In recent years, the ASC has held seven The ASC invited the Singapore AAIB to
rence investigations. trainings sessions on sea search and join the annual site survey drill in 2014.
The ASC conducted its annual survey in recovery of black boxes. The ASC invit- Both agencies worked together to evalu-
August 2015. This survey included 20 op- ed the Asia-Pacific AIAs to join those ate the results of aerial mapping from a
erators and three government agencies. activities. The ASC shared lessons learned light UAV and ground survey equipment
According to the responses from of all the from the sea crash accident investigations (a laser scanner and a precise GPS).
agencies, there are 280 aircraft, including and provided site operational databases
243 fixed-wing and 37 helicopters. Out and in-house programs for its partners to
of these, 247 are civil aircraft, and 33 are strengthen coordination among the rele- Industrial cooperation program
public aircraft. vant domestic agencies and organizations Since 2010, the ASC has pursued industri-
The statistics for civil fixed-wing and and enhance cooperation on the use of al cooperation on flight recorder readout
rotary-wing aircraft are shown in Figure 1. resources and technical personnel when and analysis. In October 2015, the ASC
• The number of civil aircraft with necessary. signed an international cooperation
CVRs and FDRs are 94.3% and 92.3%, The ASC held an exercise on under- agreement with U.S. defense contractor
6 • October-December 2017 ISASI ForumRaytheon regarding the latest technology limited knowledge about SMS, and engine ing a very high frequency omnidirectional
on flight data management and analyses flameouts. Based on international tech- radio range (VOR) nonprecision approach
to enhance the nation’s capabilities in nical collaboration, best practices and to Runway 20.
investigating aviation accidents. procedures have been established from The aircraft was destroyed by impact
Raytheon and the ASC selected Plane the relevant safety studies, joint exercises, forces and a postimpact fire. Ten passen-
Sciences Inc. of Canada to be the tech- gers survived the occurrence, and five
and excellent teamwork between the ASC
nology partner based on the company’s residents on the ground sustained minor
and the accredited representatives.
unique capability and its position as a injuries. The occurrence was the result of
An insufficient budget and shortage of
leader in flight data recorder-related controlled flight into terrain. The crew-
investigative human resources are typical
technologies. The agreement established members continued the approach below
problems for a small safety investigation
a cooperative framework between partic- the minimum descent altitude when they
agency. The ASC has applied an emergen-
ipants to execute collaborative projects were not visual with the runway environ-
cy reserve budget to support on-scene
in areas that meet the mutual interest of ment, contrary to SOPs.
wreckage handling and overseas investi-
the parties. There were 40 participants, The investigation report identified a
gation activities.
including the ASC, the CAA, airline oper- range of contributing and other safety
In addition, strong intergovernmental
ators, and the Taiwan Army, Navy and Air factors relating to the flight crew of the
cooperation was a key to success in two
Force (see Figure 2). aircraft—TNA’s flight operations and
major investigations. The following sec-
The objectives of the 10-day training safety management processes, the com-
tions describe the technical aspects and
program and three-day technology shar- munication of weather information to
lessons learned from two ATR 72 accident
ing with Plane Sciences Inc. and the ASC the flight crew, coordination issues at the
investigations. According to the final
were to civil/military joint-use airport, and the
reports of both ATR 72 accident investiga-
• improve aviation safety capability regulatory oversight of TNA by the CAA.
tions, the majority of the causal analysis
and expertise in Taiwan through This investigation identified important
issues emphasize organizational deficien-
collaboration and technology sharing learning opportunities for pilots, opera-
cy and CAA audits. This paper interprets
with North America and other inter- tors, and regulatory agencies to improve
the links between the sequence of events
national locations. future aviation safety to ensure such an
from flight recorders and highlights the accident would never happen again.
• establish readout capability of teamwork among the flight recorder There were a total of 46 findings from
next-generation flight recorders at group, other groups (e.g., flight operation, the final report and 29 safety recommen-
the ASC and receive international airworthiness), accredited representa- dations issued to the related organiza-
certification. tives, and technical advisors. tions, including TNA, the CAA, and the
• mitigate flight occurrence rate/risks MND. This paper highlights four technical
on runway safety and hazardous TransAsia Airway Flight GE222 issues found during the on-scene
weather incidents through technol- On July 23, 2014, an ATR-GIE Avions investigations.
ogy sharing, international certifica- de Transport Régional ATR 72-212A
tion, and training in order to achieve (ATR 72), registered B-22810, TransAsia
international standards. Airways (TNA) Flight GE222, with two FDR readout document contained
• increase trainees’ abilities in flight pilots, two cabin crew, and 54 passen- unclear information
data analysis and safety risk identifi- gers, was operating on instrument flight Based on the ATR’s FDR readout docu-
cation and management and conduct rules (IFR) regular public transport ment, three types of issues were identified
occurrence investigation in accord- service from Kaohsiung to Magong in the with the nonmandatory FDR parameters:
ance with ICAO Annex 13. Penghu archipelago. At 1906 Taipei local (1) Erroneous definition for sign conven-
time, the aircraft impacted with terrain
tion; (2) Mixture of two parameters into
approximately 850 meters northeast of
one; (3) Unclear descriptions on several
Lessons learned from two major the threshold of Runway 20 at Magong
Airport and then collided with a residen- parameters.
investigations tial area on the outskirts of Xixi Village In summary, certain parameters listed
The ASC recently completed two major approximately 200 meters to the south- in ATR’s FDR readout document con-
investigations that had common chal- east of the initial impact zone. At the time tained unclear or erroneous information
lenges, including an insufficient budget, of the occurrence, the crew was conduct- in their sign convention and triggering
conditions. The parameter “selected
vertical speed” was confusing, and it had
an adverse effect on the efficiency of the
occurrence investigation. A reduction
in the complexity of ATR’s FDR readout
document, by applying the principles of
ED-112A137, would assist future occur-
rence investigations.
Finding: ATR’s FDR document con-
tained unclear information that affected
the efficiency of the occurrence investi-
gation.
Safety recommendation to ATR: Review
Figure 2. Group photo of the flight recorder readout and analysis system training course. the FDR readout document for any
October-December 2017 ISASI Forum • 7erroneous information and provide terrain data and the height of truncat- FOQA is a key tool for SMS investi-
timely revisions to the manual to assist ed bush trees, the aircraft’s corrected gation
airline operators and aviation occurrence altitude was derived—denoted as Corr. Based on the CVR and FDR data, ASC
investigation agencies. Alt. (see Figure 3). Most likely, its pitot and BEA investigators worked together
tube was damaged and caused the indi- to determine the sequence of events then
cated airspeed record to drop to zero at planed further investigation efforts, in-
Flight data correction and perfor- 1906:16. The drop in each engine’s rotor cluding 20 ATR 72 line observation flights,
mance analysis speed was caused by the collision with five days of flight simulator use, 75 inter-
Wreckage distribution illustrated that the the trees. The aircraft ground speed and views, and 104 records of FOQA events.
aircraft collided with trees, and several its attitude data should be reliable and A review of the TNA FOQA monthly
items were separated from the aircraft. could be used in further impact analysis data analysis reports ( for one and a half
No evidence showed that the vertical tail with the first impacted building. years) identified recurring flight data
and elevators had collided with trees. As stated in ICAO Annex 3, the EDR is events such as long flare, GPWS warning
Based on the CVR and FDR data, an aircraft-independent measure of tur- between 500 and 1,000 feet, and heading
at 1906:11, the flight crew called a bulence. The relationship between the deviation during landing roll. There was
“go around.” The power levers of both EDR value and the perception of turbu- no evidence to indicate that those events
engines were increased to 78 degrees lence is a function of aircraft type and or the FOQA trend analysis results were
then dropped to 35 degrees. About three the mass, altitude, configuration, and discussed during safety meetings. The
seconds later, the NP speed of the number airspeed of the aircraft. The EDR values TNA FOQA program was not used as an
1 engine and indicated airspeed decayed of the occurrence flight were calculated. effective tool to identify SOP noncom-
rapidly. The NP speed of the number 2 Similar to the vertical acceleration, the pliance events and provide the relevant
engine was maintained at 100%. The EDR values were less than 0.2 most of information to flight operations for
pressure altitude contained some spike the time during the last two minutes training intervention. In addition, the
points, and its trend approximated 60 of the flight. At about 1906:00, the EDR program did not function as required to
feet. Radio height indicated that the value started to increase and reached provide a systematic tool to proactively
aircraft approached the ground, and the the maximum of 0.65 just before the identify hazards and assess and mitigate
main landing gear was changed from “air aircraft contacted with the trees. the associated risks.
mode” into “ground mode.” Examining the FDR data between The parameters and threshold values of
During the on-scene investigation 1906:00 and the end of the flight, the the TNA FOQA program were in accord-
period, the flight recorder group focused occurrence aircraft had numerous pitch ance with the manufacturer’s suggestions.
on specific questions when the aircraft and roll angle changes. The increased Based on the airline’s FOQA program,
passed through trees near Xixi Village: vertical acceleration and EDR values on the day of occurrence Flight GE220
• How to calibrate the FDR recording probably were caused by the combi- triggered three red events: altitude below
parameters (e.g., pressure altitude or nation of turbulence and the aircraft 500 feet—heading deviation greater than
radio height)? maneuver. 20 degrees, GPWS warning triggered 24
Finding: The occurrence flight had seconds, and level off below 1,400 feet
• How to derive the vertical speed from increased its rate of descent from 150
FDR parameters? above field elevation (AFE) exceeded 10
feet per minute to 1,600 feet per minute seconds. The occurrence Flight GE222
• How to evaluate the strength of tur- between 1906:05 and 1906:10, which triggered two red events: excessive bank
bulence? was the result of an elevator control angle on final approach below 100 feet
In summary, during GE222’s collision input by the captain. Based on the AFE and high rate of descent on approach
with the trees, ground effect caused the values, the turbulence strength of the between 500 and 50 feet.
pressure altitude to be unreliable. The occurrence flight during the last two However, the traditional FOQA pro-
accuracy of radio height may also have minutes could be classified as “light to gram was not configured to be able to
been affected by the dense trees. Based on moderate.” readily identify, without further analy-
sis, those events that were indicative of
noncompliance with SOPs, including
violations of approach procedures such
as descent below minimum safe altitudes.
No current FOQA program can readily
integrate all the required data sources
needed to identify some violations of
SOPs.
Finding: The TNA FOQA settings
and analysis capabilities were unable to
readily identify those events involving
SOPs noncompliance during approach
and likely other stages of flight. The FOQA
events were not analyzed sufficiently or
effectively, leaving some safety issues
in flight operations unidentified and
uncorrected. Some problems with crew
performance and reductions in safety
Figure 3. The relationship of terrain height and corrected altitude of GE222 during the indicated in the FOQA trend analyses
time flew over trees. were not investigated further. Clearly, the
8 • October-December 2017 ISASI Forumairline’s FOQA program was not capable
of facilitating proactive operational safety
risk assessments.
Safety recommendation to TNA: Imple-
ment a more advanced FOQA program
with adequate training and technical
support for the FOQA staff members to
ensure that they can exploit the analytical
capabilities of the program. As such, the
FOQA staff can more effectively identify
and manage the operational safety risks
confronting flight operations.
Emerging technologies—UAV and
flight animation
After receiving GE222 occurrence notifi-
cation from the CAA, the ASC launched a
UAV site survey team. During the second
day of investigations, the ASC site survey Figure 4. Aerial photo of the GE235 crash site.
team arrived at the crash site to evaluate
operation zones and then prepared a UAV the river. The taxi driver sustained serious actions in accordance with procedures
operation form for the CAA. injuries, and the only taxi passenger for engine number 2 flameout at takeoff,
Based on the UAV aerial survey and sustained minor injuries. Flight 235 was the occurrence could have been prevent-
ground survey data, and ASC investigator on IFR during regular public transport ed. The investigation report identified a
acquired aerial survey video clips from service from Songshan to Kinmen. range of contributing and other safety
three mass media. Those data indicated The accident was the result of many factors relating to the engine’s AFU, crew
the aircraft drifted to the left during the contributing factors that culminated in a of the aircraft, TNA’s flight operations and
final approach, and both landing gears stall-induced loss of control. During the management processes, and the regulato-
created two parallel grooves through the initial climb after takeoff, an intermittent ry oversight of TNA by the CAA.
brushwood on a heading of 170 degrees discontinuity in engine number 2’s auto- This investigation identified important
with a width between five and seven feather unit (AFU) may have caused the learning opportunities for pilots, opera-
meters. automatic takeoff power control system tors, regulatory agencies, and the aircraft
On the seventh day of the investigation, (ATPCS) sequence to activate, which re- manufacturer to improve future aviation
the ASC arranged a second UAV aerial sulted in the uncommanded autofeather safety to ensure such an accident would
survey mission of about three hours of engine number 2’s propellers. never happen again. The ASC issued
and spent another four hours finishing Following this uncommanded auto- a series of safety recommendations to
geo-image mapping. The ground resolu- feather, the flight crew did not perform TNA, the CAA, and aircraft, engine, and
tion of the aerial images is about eight the documented abnormal and emer- component manufacturers to correct
centimeters. The ASC spent another day gency procedures to identify the failure the serious safety deficiencies identified
generating high-resolution terrain data and implement the required corrective during the investigation. The manufac-
with accuracy of about 10 centimeters. actions. This led the pilot flying (PF) to turers of aircraft, engines, and AFUs have
All of the geo-images and terrain data retard power to operative engine number also implemented various safety actions
have been integrated for further applica- 1 and ultimately shut it down. The loss in response to the occurrence.
tions—flight path reconstruction, flight of thrust during the initial climb and Finding: An intermittent signal dis-
animation, etc. inappropriate flight control inputs by the continuity between the AFU number 2
PF generated a series of stall warnings, and the torque sensor may have caused
including activation of the stick shaker the ATPCS not to arm steadily during
TNA GE235 Flight and pusher. the takeoff roll. However, it was activated
On Feb. 4, 2015, about 1054 Taipei local After engine number 1 was shut down, during initial climb, which resulted in
time, TNA Flight GE235, an ATR 72-212A the loss of power from both engines was a complete ATPCS sequence including
(ATR 72-600), registered B-22816, expe- not detected and corrected by the crew in autofeathering of engine number 2.
rienced a loss of control during initial time to restart engine number 1. The crew
climb and impacted Keelung River, three did not respond to the stall warnings in a
nautical miles east from its departing timely and effective manner. The aircraft Teamwork on the AFU and torque
Runway 10 at Taipei’s Songshan Airport stalled and continued descent during the sensors examination
(see Figure 4). Forty-three occupants were attempted engine restart. The remaining The recovered wreckage represented ap-
fatally injured, including three flight crew, altitude and time to impact were not proximately 85% of the whole aircraft. The
one cabin crew, and 39 passengers. The enough to successfully restart the engine remaining unrecovered 15% of the aircraft
remaining 13 passengers and one cabin and recover the aircraft. was primarily in the area aft of the cargo
crew sustained serious injuries. One pas- Had the crewmembers prioritized their area and forward of the ice shield area.
senger received minor injuries. The air- actions to stabilize the aircraft flight path, ASC investigators worked together with
craft was destroyed by impact forces. The correctly identify the propulsion system three accredited representatives, the BEA,
aircraft’s left wingtip collided with a taxi malfunction that caused the engine the NTSB, and the TSB) and technical
on an overpass before the aircraft entered number 2 loss of thrust, and then take Continued on page 30
October-December 2017 ISASI Forum • 9COLLABORATIVE COMPONENT EXAMINATIONS
By Eric J. East, Air Safety Investigator, Boeing Commercial Airplanes
(Adapted with permission from the author’s technical paper entitled Collaborative Component Examinations presented during ISASI 2016 in
Reykjavik, Iceland. The full presentation can be found on the ISASI website at www.isasi.org in the Library tab under Technical Presentations.—Editor)
O
ne of the key links in the process employees, functions, activities, or prod- examination, and case studies of compo-
of determining probable cause ucts involved in the accident or incident nent examinations. It details the process
is the physical examination, may be invited to participate by providing and the “rules of etiquette” that have been
interpretation, and relevance of suitable qualified technical personnel to found to contribute to a collaborative
hardware and data that are recovered assist in the investigation as defined in atmosphere and successful outcomes.
from an incident or accident site. Tech- Title 49 US C.F.R. § 831.11. Party members
nique, equipment, skill, and facilities can include regulatory agencies, the air-
Boeing equipment quality analysis
have evolved considerably over time. line, pilots' and flight attendants' unions,
Equipment quality analysis (EQA) at
Examination of components has not only airframe and engine manufacturers, as
Boeing Commercial Airplanes has been
reinforced investigation postulations, but well as other parties that can contribute
in existence since 1956, encompassing all
has also on occasion provided evidence knowledge and expertise. This approach
airplane programs at the Seattle, Renton,
of the unexpected. The links that tie all encourages open collaboration between
and Everett sites in Washington state.
the equipment, plans, and interpretation the party members for both on-scene and
Our experienced EQA personnel partici-
of evidence together are the participants. off-scene activities, such as component
pate in an average of approximately 300
When examining and analyzing parts, examination, to develop a complete and
examinations per year. The EQA process
each individual participant is guided by accurate factual record. The effectiveness
is based upon collaborative investigations
his or her training, experience, abilities, as of the collaboration among examination
in which the expertise of others is highly
well as personal influences and motiva- participants—even in a very open envi-
valued. Through systematic examination,
tions. Invaluable expertise lies with many ronment such as the party system—can
the experience of various approaches,
participants regardless of whether they be enhanced by considering the unspoken
techniques, and discoveries throughout
are at the core of or in a support role to influences affecting each participant.
the history of the EQA has resulted in
the investigation. There are many variables that affect
recognition throughout the industry as a
Participation in component examina- participants’ interpretation of what is
model of component analyses.
tions by the states’ accredited represent- being witnessed, their ability to be an im-
The EQA facilities in Washington state
atives and their advisers is encouraged in partial participant, and the recommenda-
have a unique variety of collocated equip-
an Annex 13 investigation. Participation tions they will make on how to proceed.
ment found in many test and examina-
in these activities is implemented in Participants come from different fields of
expertise, experience levels, and cultures. tion laboratories. Real-time X-ray/digital
practice by the accident investigation
We must work together to collect factual radiography (DR) and computed tomog-
authority of the state conducting the
evidence during a thorough examina- raphy (CT) are typically utilized for initial
investigation. One such approach is the
tion of a component that may have been noninvasive evaluations. If any special
National Transportation Safety Board
involved in an accident—an accident that tooling or alteration is required, dedi-
(NTSB) party system in the United States.
may have resulted in serious or fatal inju- cated machining equipment is available.
In the party system, organizations whose
ries. The results of the examination may Highly accurate dimensional evaluations
show that a component contributed to are conducted using techniques such as
this accident. The component in question laser surface and optical measurement
may have been manufactured by the com- equipment. Hydraulic test benches, en-
pany you work for, installed on the air- vironmental chambers, form scan, mass
plane that you maintain, or operated by spectroscopy, and digital microscopy are
the airline that you represent. How do you just some of the other capabilities readily
Eric East maintain impartiality? Are there personal, available at our EQA labs. If follow-on
professional, or political pressures from evaluation is needed, access to collocat-
has been with Boeing since 2006 and back home? Do you feel overwhelmed by ed specialized research and materials
has worked in areas such as production all the experts in the room? Are you the laboratories is also available, including
support engineering, flight testing, and expert who already knows the answers? EMI (electromagnetic interference), EME
customer introduction field service before Do you want to be the one who finds the (electromagnetic effects) lightning, chem-
joining accident investigation in 2015. Eric “ah ha” discovery? We have to be aware of ical, and metallurgical facilities.
received a bachelor of science degree in all of these unspoken influences and how In order to maintain the chain of
mechanical engineering from the Uni- they can contribute to the environment of custody of examination parts involved
versity of Tennessee, Knoxville. Prior to
the examination. with government investigations, Boeing
joining Boeing, Eric worked in a variety of
mechanical and process engineering roles The information that follows will pro- air safety investigation and EQA organi-
in the petrochemical industry. vide a brief overview of component ex- zations maintain a partnership with the
amination at Boeing, current methods of Western Pacific Regional Office of the U.S.
10 • October-December 2017 ISASI Foruminformation to the investigations that the
examinations supported.
57% - Customer Airlines Includes - Continued
Operational Safety Program (COSP) Case Study 1—COPA Flight 201
The first case study deals with the COPA
Flight 201 accident that occurred in
37% - Boeing Manufacturing & Quality Includes - Panama in 1992. This accident involved
a COPA Airlines B-737-200 enroute from
Boeing Engineering and Suppliers Panama to Colombia that broke up in
flight and crashed into dense jungle in
Panama after deviating around a storm.
6% - Boeing Air Safety Investigations (ASI) Unfortunately, all 40 passengers and sev-
en crewmembers were lost, making this
the worst aviation accident in Panama.
Figure 1 EQA customer distribution.
An investigation ensued in which Boeing
NTSB. We maintain robust processes for knowledge base. In turn, this greatly en- provided technical advisers to the U.S.
component shipment; and when needed, hances EQA’s pattern recognition capabil- NTSB.
onsite secure storage is available and only ities and also helps to build relationships The digital flight data recorder (DFDR)
accessible by NTSB personnel. with airlines, suppliers, and government was recovered during the investigation,
agencies that we might work with during and flight data were successfully recov-
incident or accident investigation sup-
Pattern recognition ered. Roll attitude and heading informa-
port. tion from the DFDR confirmed inter-
Boeing EQA performs examination and
analysis of components through all phas-
es of the component’s life from develop- Rules of etiquette
ment, test, and production to in-service Over many years of conducting these
and accident investigations. Analytical examinations, the Boeing EQA team has
services can include test methodology created a set of rules that are presented at
and planning as well as failure mode the start of each examination. These rules
and probable cause identification. This of etiquette (see Figure 2) help to estab-
accumulated wealth of information from lish the ground rules and structure of the
the examinations of many components is examination. More importantly, they also
conducive to the recognition of patterns help set the tone, or atmosphere, in which
but does not preclude the discovery of the work is conducted. We have found
new phenomenon. that these rules help maintain focus while
The primary role of EQA is to support establishing that every participant’s input
the development of new aircraft and is valued and respected.
continuing airworthiness of in-service In the examples that follow, the pro-
Figure 3 Attitude direction indicator.
aircraft. The majority of EQA workload cesses, technical capability, and expe-
is outside of air safety investigation, as rience of Boeing EQA helped to enable mittent errors in the attitude direction
shown in Figure 1. The investigation work collaboration among examination par- indicators (ADI) (see Figure 3) due to
conducted throughout the year for the ticipants. In this atmosphere, important the high rates of change observed that
development, production, and in-service findings were confirmed and unexpected the system was not capable of. DFDR
areas helps our experts expand their discoveries were made that provided key review also confirmed that the flight
crew attempted to maneuver the airplane
1. If in doubt, always ask the investigator in-charge. to correct the indicated attitude errors.
Unfortunately, the CVR recording was not
2. Always respect the opinions of others. All ideas or suggestions are welcome.
available as the CVR was not operating
3. Stay to plan but be flexible depending on progressive developments. properly during the accident flight. It was
4. Any member has the right to put forth suggestions/ideas before the team. believed to have been damaged during
5. At any time, any member of the team may request a halt or temporary delay previous maintenance activities.
in the examination/test to discuss any concerns, proposals, modifications or Attention then turned to examination
changes to the originally proposed examination/test prior to continuing with of components recovered from the acci-
any phase of the analyses. When in doubt, pause and ask others. dent site. Over the course of the investi-
6. Try to have only one conversation in the room at a time; avoid side discus- gation, several manufacturers were asked
sions as much as possible. to perform component examinations.
7. Only the EQA team member will handle the parts under direction of the team The investigation team worked together
to prevent too many people from handling the parts. to determine which components would
help explain what happened during the
Figure 2 Boeing EQA rules of etiquette. accident. Boeing’s EQA lab focused on
October-December 2017 ISASI Forum • 11VG2). In the NORMAL setting,
VG1 provides indication to the
captain’s ADI, while VG2 pro-
vides independent data to the
first officer’s ADI. When the
flight crew determines one of
the vertical gyros is unreliable,
the switch is moved from the
NORMAL position to energize
either VG1 or VG2 to supply
information to both attitude
reference systems. The air-
Figure 6 Standby artificial horizon indicator.
plane also contains a standby
artificial horizon indicator (see Figure 6) plug and an armature pole labeled as
Figure 4 Vertical gyro transfer switch. that serves as a completely independent “5” at the area highlighted by the arrow.
backup system for the attitude reference The adjacent armature pole surface was
a number of attitude reference system system. It provides its own visual indica- examined by a scanning electron micro-
components, including the panel contain- tion of airplane attitude in pitch and roll scope (SEM) and found to have an im-
ing the vertical gyro transfer switch, the using its own gyro, which is independent pression consistent with the dimensions
roll synchronization portion of VG1, and of VG1 and VG2. In this accident, the of the coil wire. This was determined to
the standby artificial horizon indicator. vertical gyro transfer switch was found be the location of an intermittent short in
These examinations were conducted with in the BOTH ON VG1 position. With the the roll synchronization coil. The exam-
participants from the NTSB, Panamanian switch in this position, both the captain’s ination team determined that resulting
DAC, COPA, and the component manu- and first officer’s ADIs were displaying voltage loss on this coil can cause the
facturers. information from VG1. attitude direction indicator to freeze or
The attitude reference system on the During the examination of the transfer jam intermittently in position.
737-200 provides the captain and first switch at the Boeing EQA lab, a broken In this examination, the collaborative
officer with the airplane's attitude in both wire in the COMPASS portion of the panel investigative process narrowed down
PITCH and ROLL axes during flight. Two was found. The fracture was determined the list of relevant components to be
systems are installed; system No. 1 feeds to have resulted from mechanical over- considered for examination. There was
information to the captain's ADI, while load and was unrelated to the VG1 circuit. willingness on the part of participants to
system No. 2 feeds information to the When the VG1 roll synchro rotor was take new suggestions into account, such
first officer’s ADI. In addition to the ADIs, initially examined, an open circuit was as looking for short circuits to ground
the system consists of amplifiers, vertical observed between the yellow and green on VG1 by shifting focus beyond just the
gyros, and a vertical gyro transfer switch coil lead wires of the rotor (Figure 7). open circuit between lead wires found
(see Figure 5). The vertical gyros (VG1 During the examination of the cause for during initial continuity checks. The
and VG2) operate when the airplane is an open circuit, EQA personnel found a experience of participants was utilized to
displaced in the roll or pitch plane by location (Figure 8) where a winding was recognize patterns during physical exami-
transmitting electrical signals from roll/ compromised and suggested to the team nation to determine that the anomaly was
pitch synchros within the gyro, which are that a short to the iron core ground may likely present since the original manufac-
amplified to drive the horizon tape on the exist in this area. As the location in ques- ture and had not been caused by impact.
ADIs. The vertical gyro transfer switch tion was found covered by the original
shown in Figure 4 has three positions conformal coating, this anomaly had ap-
(BOTH ON VG1, NORMAL, and BOTH ON parently been present since the part was Case Study 2—Oxygen Mask
originally manufactured. As Examination
the examination progressed, This example is from investigation activ-
the open circuit in the coil ities concerning a B-737 flight deck fire.
was determined to be the This event occurred shortly after push-
result of impact damage and back and caused extensive fire damage in
was not associated with the the flight deck area. All passengers and
winding anomaly. The focus crew were able to safely evacuate. Boeing
then shifted to examining was asked to participate in the investiga-
the winding anomaly more tion as a technical advisor to the NTSB.
closely. Boeing’s EQA performed an examination
Figure 8 shows the loca- on the remnants of a flight crew oxygen
tion of the anomaly after mask (see Figure 9) to determine the po-
the conformal coating was sition of the regulator input knob to assist
removed. One of the wires in determining possible oxygen leakage
from the coil was found scenarios.
Figure 5 Attitude reference system. pinched between a nylon The 737 flight crew oxygen system
12 • October-December 2017 ISASI ForumYou can also read
