SOAM concept of accident analysis Mirabel Deicing accident

8/13/2019 SOAM concept of accident analysis Mirabel Deicing accident

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Accident Investigation Report

De-Icing AccidentMirabel Airport

ATM Safety Investigation

& Analysis Course

SAA


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Safety Investigation & Analysis # 2 Ddale Asia Pacific

Organisational

and System Factors

Latent Conditions(adapted fromReason, 1990)

Active

Failures

Contextual

Conditions HumanInvolvement

Limited window/s

of opportunity

Absent or Failed

Barriers

ACCIDENT

People, Task,

Environment

The Reason Model


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Summary of the Event

Miscommunication Leads to Three

Fatalities During Ground Deicing of

Aircraft.


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The Royal Air Maroc Boeing 747-400 was preparing for a

scheduled flight from Mirabel International Airport,

Montreal, Canada, to Casablanca, Morocco, via New York.

The B-747 crew heard the words dgrivage termin

(deicing completed) on the radio frequency assigned to thedeicing crew.

The captain assumed that the operation had been

completed and that the deicing crew had left the area.

Unknown to the B-747 flight crew, two deicing vehicleswere still positioned on opposite sides of the fuselage

forward of the horizontal stabilizers, with five deicing

personnel who were continuing the deicing operation.


7/18Safety Investigation & Analysis # 7 Ddale Asia Pacific

As the aircraft moved forward, its horizontal stabilizersstruck the telescoping booms of the deicing vehicles,

overturning the vehicles.

three occupants of the two buckets (cherry pickers) were

killed when they struck the ground, and the two vehicle

drivers received minor injuries.


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What happened

Brief summary

of

loss: injuries,

fatalities,

equipment etc

Noise of the engine

prevented snowman to

hear pilots TX properly

De icing area was not

visible from TWR for the

controller

Captain did not confirm

with the de icing crew

about the completion

Transport Canadas laxmentality towards foreign

carriers and private

contractors

No proper Training on

Engines on

configuration.

ADM managementsfailure to prevent deicing

with engines on.

ZZ Zzzzzzz

YY Yyyyyy

Pilot heared the words

De icing completed with

out any station name

CAILs failure to provide a

copy of its de icing

procedure to RAM

ACCIDENTABSENT OR

FAILED

BARRIERS

HUMAN

INVOLVEMEN

T

CONTEXTUAL

CONDITIONS

ORGANISATIONA

L

FACTORS

OTHER

SYSTEM

FACTORS

PIC taxied with

out proper

communication

with theground crew

Pilot did only a

visual check

from th cockpit

Engine on deicing waspervalent with the ADMs

knowledge

No SOPs to do de iceing by

RAM

No checking on wearing

safety harness andprotective gear.

NO ATC

VISUAL

REFERENCE

S TO

DEICING

FACILITY

Snowman

agreed to de

ice with

engines on

Apron controller not

required to confirm withthe crew thRat the

perimeter is clear.

Different communication

procedures follwed by the

deicing crew

No TX on the CAIL

frequency after beginning

of the deicing

Flight attendant not

required to prevent taxi

Non availability of aircraft

marshaller at ground

during de icing

RAM deicing with engines

ON

ADMs failure to issue

deicing licence

Animosity between CAIL

de icing crew and private

contractors

competition on deicing

operations between

Airliners and contractors

Snowmans heavy work

load

XX Xxxx

Iceman notpreventing

snowman to

deice with

engines on

Apron

controller

assumed that

ACFT started

after deicing

LACK OF SOP

REGARDING

DE-ICING

FLIGHT ATT. NOT

REQUIERED TO

INFORM THE

CREW ABOUT

A/C PERIMETER

Not having enough crew to

handle B747 de icing

CONTRADICTI

NG TC AND

ICAO

CIRCULARS

TC LIMITATIONSTO CHECK

FOREIGN

CARRIERS AND

CONTRACTOR

NO AGREED

UPON VISUAL

SIGNAL TO

INDICATE THE

COMPLETIONOF WORK

inadequate

communications

equipment


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The errors and/or violations (actions or omissions) by people at the

scene which triggered the accident.

Human involvement 1

Human involvement 2

Human involvement 3 Human involvement 1

..

Human Involvement



The task, situation, environment, or people conditions existingimmediately prior to, or at the time of the accident.

Contextual Conditions

Contextual condition 1

Contextual condition 2

Contextual condition 3 Contextual condition 4

..



The organisational and system factors (failures) that created the

prevailing Contextual Conditions or allowed them to exist (~ task,

environmental, people conditions).

Organisational Factors

Organisational factor 1

Organisational factor 2

Organisational factor 3 Organisational factor 4

..



Recommendations:

Absent or Failed Barriers

IMPLEMENTATION OF PROPER SOP

REGARDING DE-ICING

OPERATION INSTALATION OF A PROPER

CCTV SURVEILLANCE SYSTEM IN

TWR Recommendation A4

..Corrective actions to address deficiencies in the barriers which shouldor could have prevented the occurrence



Recommendations:

Organisational Factors

Provide adequate manpower to

carry out de-icing with engines

running RAM should assure that proper

procedure are in place for the

cabin crew to inform the flightcrew about any safety issue..

Corrective actions to address organisational deficiencies which

contributed to the occurrence



Key Learnings

(for Our Organisation)

Compliance with the R/T

phraseology procedure

Intervene immediately in theinterest of safety even though you

are not required to do so by the

procedure Key Learning 3

Key Learning 4

..

Lessons from this occurrence which can

be applied across our organisation



Questions

or

Comments?

Documents

SOAM concept of accident analysis Mirabel Deicing accident