SUBJECT - EQUIPMENT, TOOLS AND PARTS FOR AIRCRAFT
INTRODUCTION - REGIONAL AIRLINES SAFETY STUDY
Between October 1995 and July 1997, the Bureau of Air Safety
Investigation undertook a study of the safety of Australian
regional airlines. The objectives of this study were to:
(a) identify safety deficiencies affecting regional airline
operations in Australia; and
(b) identify means of reducing the impact on safety of these
For the purpose of the survey, regional airlines were grouped
according to the number of passenger seats fitted to the largest
aircraft by that airline in January 1997. The groups are defined as
(a) Group 1: 1 - 9 seats;
(b) Group 2: 10 - 19 seats; and
(c) Group 3: more than 20 seats.
The study involved analysing data obtained from:
(a) responses to a survey of Australian regional airline
(b) discussions with Australian regional airline employees and
(c) air safety occurrence reports involving regional airlines over
a 10-year period (1986-1995) from the BASI database.
This Safety Advisory Notice addresses one of the safety
deficiencies identified as a result of this study.
Some maintenance engineers do not have ready access to all the
tools, equipment and parts needed to perform their duties.
When respondents were asked to nominate the greatest safety
problem they faced, a lack of spare parts was mentioned more
frequently than any other maintenance issue. Twenty-three
respondents (or 40%) of the maintenance personnel who replied,
considered that the tools and equipment needed to perform their job
were not readily available. The majority of respondents (17 out of
19) who worked for Group 1 or Group 2 airlines, were satisfied with
the availability of tools and equipment. However, approximately
one-half of those (24 out of 45) who worked for Group 3 airlines,
were dissatisfied with the availability of tools and
Examples of survey responses
"The increasing maintenance costs, availability of spares, etc.,
creates scheduling difficulties and puts pressure on crews to fly
aircraft with unserviceable items."
-Pilot, respondent 552
"The unserviceable aircraft being put back on line due to lack of
-Licensed Aircraft Maintenance Engineer, respondent 409
"One of them is lack of or insufficient maintenance done on an
aircraft. Lack of engineering manpower often causes delays to
rectify faults prior to departure. Accumulation of defects which
eventually grounds the aircraft. Lack of support by management head
office to supply urgently needed equipment for aircraft
-Flight attendant, respondent 109
"Commercial pressures to fly with engineering problems. The lack
of spare parts or aircraft mean management puts extreme pressure to
continue operating and also to maintain schedule even though
aircrew may well want time to analyse problems."
-Pilot, respondent 509
"The haste with which a job is expected to be done in. Lack of
spare parts and poor tooling."
-Licensed Aircraft Maintenance Engineer, respondent 147
"Workload lack of parts, tooling."
-LAME respondent 300
The Canadian Aviation Regulations (CAR) Commercial Air Service
Standards, 726 - Air Operator Maintenance, addresses the
responsibility of the operator for spare parts availability, and
specifically requires sufficient supplies of spare parts to ensure
the timely rectification of defects in regard to Minimum Equipment
List (MEL) provisions.
The British Civil Aviation Publication (CAP) 360, Part Two, deals
with Air Operator Certificates - Maintenance Support. Paragraph 15
enumerates substantial requirements of the operator regarding the
provision and storage of spares.
Two of these requirements are:
(1) CAP 360 15.1, which refers to sufficient spares being
available to ensure defects can be promptly rectified; and
(2) CAP 360 15.2, which refers to the numbers and placement of
essential spares to support the rectification of defects in systems
required for operation, taking account of the operators' Minimum
Equipment Lists, to ensure successive defects will be promptly
The Australian Civil Aviation Regulations do not address the
responsibility of an operator with regard to spare parts.
A fatal accident involving a regional airline aircraft that
crashed at Young, NSW on 11 June 1993, highlighted the safety
implications of a lack of serviceable spares.
One of the findings of this report stated that "the autopilot was
inoperative, and had been for an extended period prior to the
flight "(73 days). The autopilot was a MEL item that required
rectification within a period not exceeding 10 days. It was issued
with Permissible Unserviceability (PUS) approvals for the extended
period. During this period, another aircraft operated by the
airline experienced an unserviceable autopilot. The airline manager
requested approval of a PUS for the second autopilot
The airline operator had not provided adequate serviceable
components to rectify the autopilots within the MEL period.
The results of the regional airlines safety study, together with
the safety issue highlighted by the occurrence referred to in this
document, suggest that some operators may be compromising the
safety of fare-paying passengers by not ensuring that adequate
spare parts are available to meet the routine maintenance
requirements of their fleets. The lack of appropriate domestic
regulation may be a contributing factor to this safety issue. The
reported lack of tools and equipment, particularly in Group 3
airlines, is also of concern.