Safety Advisory Notice SAN19980104

Safety Advisory Notice issued to: Owners and operators of unlicensed aerodromes

Recommendation details
Output No: SAN19980104
Date issued: 21 September 1998
Safety action status: Closed



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 deficiencies.

For the purpose of the survey, regional airlines were grouped according to the number of passenger seats fitted to the largest aircraft operated by that airline in January 1997. The groups are defined as follows:

(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 employees;
(b) discussions with Australian regional airline employees and managers; 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 unlicensed aerodromes used by some regional airlines may not be suitable for airline operations. In addition, reliable information on some unlicensed aerodromes may not always be available.


Survey Results

A licensed aerodrome is required to meet all the appropriate requirements in Civil Aviation Regulations (CARs) and has its details published in Aeronautical Information Publications (AIP). Any changes to the published status of a licensed aerodrome will be published in Notices to Airmen (NOTAMs). However, when using unlicensed aerodromes, it is the responsibility of flight crews to obtain information on the state of the aerodrome from its owner/operator. As not all pilots use unlicensed aerodromes, only 60% of pilots completing the survey answered the questions pertaining to unlicensed aerodromes.

Twenty-two per cent of pilots responding to the question in the survey relating to unlicensed aerodromes, agreed that the condition of some unlicensed aerodromes they used was hazardous. The same proportion of pilots answered that they could not always get reliable information on the condition of the unlicensed aerodromes they used.


Airline operations into unlicensed aerodromes are permitted, provided the aerodromes meet minimum prescribed standards and are maintained to those standards. Unlicensed aerodromes of smaller dimensions are permitted to be used by aircraft of lower operating weights; however, such aircraft operating into these aerodromes must be flown in visual, daylight conditions (Appendix 3 Civil Aviation Order Part 82.3).

Many unlicensed aerodromes used by regional airlines were previously licensed and established to aerodrome standards. The main reason for delicensing, provided by aerodrome owners and operators, was the administrative cost of maintaining the aerodrome licence. Some financial benefit to the aerodrome owner may have resulted by adopting the smaller dimensions of an unlicensed aerodrome.

Reporting procedures

Use of an unlicensed aerodrome by regular public transport (RPT) flights requires airline operators to establish a reporting system (Civil Aviation Order Part 82.3). As part of this reporting system, the airline operator must nominate a reporting officer to conduct the aerodrome inspection and report on its status. The condition of the aerodrome must be conveyed to the airline operator before the arrival of each scheduled flight.

Many regional airlines use a "negative" reporting system whereby only unserviceable conditions are reported. It is assumed that the aerodrome is serviceable when a report is not received.

Responsibility for ensuring the serviceability of unlicensed aerodromes used by RPT flights, lies with the airline and not the aerodrome owner or operator. However, reporting officers are charged with the responsibility of ensuring the aerodrome serviceability is accurately reported to the airline.

The Civil Aviation Safety Authority (CASA) only approves the airline operator's reporting system. It is the airline's responsibility to ensure reporting officers are fully conversant with the standards and have been appropriately trained, as required by CAR 89V.

Related occurrences

A search of occurrences over a 3-year period revealed only a small number of reported occurrences, the majority of which resulted from the presence of people, animals or equipment on the movement area during an aircraft's approach to land or following takeoff. However, one occurrence resulted in serious damage to an aircraft.

"Towards the end of the landing roll the aircraft encountered a soft wet area on the runway, resulting in mud and stones being thrown up over the aircraft, causing stone damage to all propeller blades, the right side fuselage panels, and right side cockpit, and cabin windows. This soft area was not discernible from the air. The NOTAMs obtained by the pilot prior to the flight indicated that none were current for that aerodrome. Rain had fallen earlier at the aerodrome, but not at the homestead; therefore, the property owner was not aware of the soft wet areas on the runway."

BASI Report 9601565


As part of CASA's scheduled surveillance of an airline operator, any unlicensed aerodrome serving as a destination on that operator's Air Operator's Certificate (AOC) requires annual inspection by an aerodromes inspector. The airline operator is advised in advance of these inspections. In addition, and as a courtesy, the aerodrome owner is also advised. Despite being forewarned of an inspection, a number of unlicensed aerodromes did not meet the required standards.

Aerodrome inspectors found large stones, sink holes, washouts, ruts, sand drifts, overgrown vegetation, tussocks and soft patches to be the main physical shortcomings of these aerodromes. They were concerned that these conditions had not been reported to the airline operator, as required, or that the reports were ignored by flight crews.

Despite these reported conditions, only one aerodrome in the last three years was considered to be in such poor repair as to warrant having this destination removed from the operator's AOC.

Non-compliance notices

A non-compliance notice (NCN) is a formal notification from CASA to an AOC holder, advising that a safety deficiency exists. NCNs are issued to airline operators against deficiencies in airfield reporting procedures and unlicensed aerodrome standards.

Aerodrome inspectors estimated that the majority of NCNs, approximately 70%, were related to sub-standard physical characteristics of the aerodrome. Aerodrome markings and inadequate fencing were other significant deficiencies. Records show many NCNs that were issued following each inspection for some aerodromes, were for similar reasons. Inspectors cited ignorance of published standards and inadequate maintenance as the main reason for the reissue of some NCNs.

Aerodrome maintenance

Maintenance of aerodromes owned by municipalities is mostly funded by rates. Some of the community aerodromes have access to funding through government grants or subsidies but the majority of the unlicensed aerodromes are owned and maintained privately. Revenue raising measures such as landing fees to cover the cost of aerodrome maintenance, are not feasible because of the limited number of aircraft movements. Likewise, low passenger numbers preclude the raising of funds from ticket taxes.

It was reported that maintaining an unlicensed aerodrome to airline standards was difficult to justify when the average utilisation by airline aircraft is only one or two movements per week. Difficulty in obtaining access to suitable equipment such as graders and heavy rollers for maintaining these airfields, was cited by aerodrome inspectors as a major obstacle to the continued upkeep of natural surface runways.


Aerodrome maintenance and adherence to published standards is important to the safety of fare-paying passengers. Acceptance of lower standards jeopardises that safety. In order that airline flight crews can make informed decisions about the use of unlicensed aerodromes, aerodrome owners and operators have a responsibility to ensure that reporting officers are adequately trained to perform their inspections and that they report aerodrome conditions consistently and accurately.

Reporting procedures used by some regional airlines may not be adequate to allow flight crews to make informed decisions about the use of unlicensed aerodromes. "Negative" reporting systems can create uncertainty in the minds of flight crews. When the serviceability of an aerodrome is not communicated, flight crews have no way of knowing whether an aerodrome inspection has been carried out, or that the inspection report was not passed to them. This lack of communication between airline operators and aerodrome reporting officers appears to be the cause of much misunderstanding about aerodrome serviceability.

Airline operators using unlicensed aerodromes should evaluate the adequacy of the training given to reporting officers and consider certification of that training as a means of establishing quality control and standardisation.

The lack of reported incidents does not make an argument for the relaxation of the existing aerodrome standards.

Output text

Owners and operators of unlicensed aerodromes used by regional airlines should take note of the safety deficiency identified in this document and take appropriate action.

As a result of the investigation into this safety deficiency, the Bureau simultaneously issues Safety Advisory Notice SAN980105, alerting operators of regional airlines to this safety deficiency.

Initial response
Date issued:
Response from: Regional Airlines
Action status: Not Required
Response text:
Last update 01 April 2011