Investigation number
AO-2010-008
Occurrence date
Location
Canberra Aerodrome
State
Australian Capital Territory
Report release date
Report status
Final
Investigation level
Systemic
Investigation type
Occurrence Investigation
Investigation status
Completed
Aviation occurrence type
Turbulence/windshear/microburst
Occurrence category
Incident
Highest injury level
None

On 31 January 2010, an American Aircraft Corporation Grumman Traveller AA-5 aircraft, registered VH-ERP, was being operated on a visual flight rules private flight from Temora, New South Wales to Canberra, Australian Capital Territory. At about 1630 Eastern Daylight-saving Time, on late final approach to runway 12 at Canberra Aerodrome, and at an altitude of about 150 ft above ground level, the aircraft experienced severe turbulence that resulted in a brief loss of control. The pilot recovered control and landed on runway 12.

The investigation determined that it was probable that the severe turbulence was generated by a combination of the wind conditions on the day and the position of the two buildings located about 220 m and 290 m upwind from runway 12. In addition, there were no standard criteria for assessing the potential local wind effect of aerodrome building developments on aviation operations, and no national building codes for aerodrome developments that address the phenomena of building-induced turbulence.

The aerodrome operator had commissioned pre-construction wind impact assessments of the two buildings to the north of runway 12. These reports concluded that the buildings would not result in adverse wind effects on aircraft operations. This conclusion was based in part on the assessment that use of runway 12 was unlikely in northerly wind conditions. However, operations to that runway remained possible in those conditions without any alert to affected pilots about possible risk. By contrast the Canberra Aerodrome information in the En Route Supplement Australia alerted pilots of the possibility of severe turbulence during touchdown on runway 35 in strong westerly winds.

Subsequent to this occurrence, the Department of Infrastructure, Transport, Regional Development and Local Government established the National Airports Safety Advisory Group (NASAG). NASAG's role is to examine airport planning issues, including the potential local wind effects of buildings on aircraft operations, and to develop a set of universal guidelines and policy material for application at state and local levels. In addition, Airservices Australia is progressing the installation of wind shear detection technologies at several aerodromes. There is the potential that one of those installations could be at Canberra Aerodrome.

Aircraft Details
Manufacturer
American Aircraft Corp
Model
AA-5
Registration
VH-ERP
Serial number
AA5-0691
Operation type
Private
Sector
Piston
Departure point
Temora, NSW
Destination
Canberra, ACT
Damage
Nil