Midair collision involving Cessna Aircraft 152, VH-FMG and Liberty Aerospace XL-2, VH-XLY, Casula, New South Wales, on 18 December 2008

Abstract

On 18 December 2008, a Liberty XL-2 aircraft, registered VH-XLY, collided in midair with a Cessna 152 aircraft, registered VH-FMG, near Casula, New South Wales (NSW). The Liberty was engaged in a pilot licence flight test; the Cessna was engaged in pilot training. The pilots of both aircraft were operating in uncontrolled airspace under the visual flight rules, in good weather. The collision severely damaged the Cessna, which descended in an uncontrolled manner before impacting terrain, fatally injuring the two occupants. The Liberty was able to continue flying and landed at Bankstown Airport, NSW.

The two pilots in the Liberty had previously sighted the Cessna while they were tracking towards an inbound reporting point. They subsequently lost sight of the aircraft prior to the collision. The investigation found that the limitations imposed by the visual size of the Cessna and its lack of relative motion in relation to the Liberty, the focussed workload of the student under test at the time, and obstructions posed by the aircraft's structure were likely factors in them being unable to re-sight the Cessna before the collision.

The investigation did not identify any organisational or systemic issues that might adversely affect the future safety of aviation operations. However, the factors involved are a salient reminder to all pilots that there are limitations with visual flight procedures and that, regardless of pilot's experience, they need to remain vigilant at all times. That is particularly the case when in the vicinity of other aircraft.

As a result of a number of midair collisions in Australia, the Civil Aviation Safety Authority (CASA) conducted two reviews into operations at General Aviation Aerodrome Procedure (GAAP) aerodromes. Although this accident occurred in Class G airspace (uncontrolled airspace), due to its proximity to an inbound GAAP reporting point, CASA referred to it in those reviews. Those reviews made a number of recommendations to enhance the provision of GAAP procedures education and training and on the current implementation of GAAP. On 3 June 2010, CASA introduced full Class D airspace at all aerodromes that previously operated under GAAP in Australia.

Response to Coroner’s findings

The ATSB notes that on 2 May 2013 the Deputy State Coroner, Magistrate P. A. McMahon, handed down his findings in the inquest into the deaths of the two occupants of a Cessna 152 aircraft, registered VH-FMG, following a midair collision with a Liberty XL2 aircraft, registered VH-XLY.

The Coroner’s findings were substantially in accordance with those of the ATSB. The Coroner did not make any recommendations arising out of his findings.

The factors identified in the report and the Coroner’s findings highlight the limitations with visual flight procedures and the need for vigilance at all times, particularly in the vicinity of other aircraft and in potentially high traffic areas.

Cooperation with Coroners

Australian Transport Safety Bureau (ATSB) investigations are conducted with the objective of providing findings that can be used to improve transport safety in the future. Coronial Inquests are a separate process to the ATSB investigation and they are usually supported by their own investigation and brief of evidence. However, as Inquests also have the objective of seeking to prevent a death occurring again, the ATSB provides cooperation through the explanation of the ATSB's findings in its report. 

The ATSB appreciates the interest of Coroners in working with the ATSB in the interests of improving safety. The Coroner formulated his findings and recommendations independently of the ATSB. However, the ATSB supports the coronial process and in the interests of ensuring that safety information is made available to the broadest audience the ATSB is making this publication.