Aviation safety investigations & reports

Collision with terrain involving SOCATA TB-10 Tobago, VH-YTM, near Mount Gambier Airport, South Australia, on 28 June 2017

Investigation number:
AO-2017-069
Status: Completed
Investigation completed
Phase: Final report: Dissemination Read more information on this investigation phase

Final Report

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What happened

On 28 June 2017, the pilot of a SOCATA TB-10 Tobago aircraft, registered VH-YTM, was conducting a community service flight from Mount Gambier Airport, South Australia, to Adelaide, South Australia. The flight was organised by the charity Angel Flight to transport a passenger for medical treatment and an accompanying family member. The aircraft took off at 1020 Central Standard Time as a private flight operating under visual flight rules. After reaching a height of 300 ft, the aircraft descended and impacted terrain about 70 seconds after take-off. The pilot and both passengers were fatally injured and the aircraft was destroyed.

What the ATSB found

The ATSB found that the pilot took off in low-level cloud without proficiency for flight in instrument meteorological conditions. Shortly after take-off, the pilot likely lost visual cues and probably became spatially disorientated, resulting in loss of control of the aircraft and collision with terrain.

The ATSB has previously established that the fatal accident rate of private operations is substantially higher than commercial passenger transport (eight times higher than charter and 27 times higher than low capacity regular public transport, with no fatal accidents on high capacity RPT). This ATSB investigation further established that community service flights conducted on behalf of Angel Flight Australia (Angel Flight) had substantially more occurrences, accidents and fatal accidents per flight than other private operations (including that the fatal accident rate was more than seven times higher per flight than other private flights).

It is almost certain this higher occurrence rate is due to community service flights being exposed to different operational risk factors when compared to other private operations. The ATSB found two aspects in particular likely contributed to this higher rate. These were the potential for some pilots to experience perceived or self-induced pressure by taking on the responsibility to fly ill, unknown passengers, at scheduled times to meet predetermined medical appointments, often with an expected same day return; and the required operation to unfamiliar locations, and limited familiarity with procedures in controlled airspace (associated with larger aerodromes). These factors were consistent with lessons learned from the US experience, the occurrence data analysis of Angel Flight organised flights, and submissions made to a Civil Aviation Safety Authority (CASA) public consultation on changes to community service flights.

The types of occurrences where flights organised by Angel Flight were statistically over-represented (as a rate per flight) compared to other private operations were consistent with these operational differences. In particular, occurrences which involved pre and in-flight planning and decision making errors were over-represented, which was a factor in this accident as well as in a previous fatal accident in 2011 which involved an Angel Flight organised passenger flight. The higher occurrence rate in particular types of occurrences indicated an elevated and different risk profile in Angel Flight organised private community service flights compared with other private operations.

Angel Flight had insufficient controls in place, and provided inadequate guidance to pilots for addressing the additional operational risks associated with community service flights. Furthermore, the ATSB found that there were limited opportunities for Angel Flight to be made aware of any safety related information involving flights conducted on its behalf, restricting its ability to identify and manage organisational risks.

It was identified that Angel Flight did not consider the safety benefits of commercial flights when suitable flights were available. While Angel Flight arranged and paid for commercial flights (18 per cent of all flights) for capital city transfers, or when private pilots cancelled, it was estimated that nearly two-thirds of the private flights conducted for Angel Flight had a commercial regular public transport option available, which offered considerable safety benefits when compared to private operations. Of these, at least 22 per cent had suitable same day return flights four or five days a week, with at least two-thirds of these regular public transport flights being of comparable cost to Angel Flight when compared with the volunteer costs. The ATSB acknowledges that there will be passengers who cannot travel on regular public transport flights, and that there are times and locations where this option is not available or suitable. However, Angel Flight should still consider the use of suitable commercial flights as a primary option when arranging and paying for flights to assist financially disadvantaged people. On the day of the accident, suitable and cost-comparative commercial passenger flights were available.

CASA did not have a system to differentiate between community service flights and other private operations that would allow for ongoing oversight and review of the safety of these flights. Differentiation would allow for the identification of areas of specific concern through evidence-based analysis, and consideration of appropriate risk controls to be applied to all organisations offering community service flights. The lack of this differentiation limited CASA’s ability to identify and manage risks associated with community service flights.

What's been done as a result

Angel Flight Australia advised it had received permission for all registered pilots to access the community service pilot education online course Public Benefit Flying: Balancing safety and compassion, developed in the United States by the Aircraft Owners and Pilots Association Foundation’s Air Safety Institute, while an Australian course is developed. It also indicated it was facilitating the sharing of all CASA safety seminar schedules, with a request for feedback on attendance and the content presented, and engaging a volunteer to develop systems and processes to manage its safety risks. Additionally, pilot, passenger and health referrer guidelines had also been updated. The ATSB will monitor the progress of these safety actions.

The ATSB has issued a safety recommendation to Angel Flight Australia to take action to consider the safety benefits of using commercial flights where they are available to transport its passengers.

The ATSB was advised CASA had implemented a new safety standard regarding the conduct of community service flights. These requirements commenced on 19 March 2019 and included:

  • A flight notification (full flight notification or SARTIME) that identifies the flight as a community service flight to be submitted to Airservices Australia.
  • Pilots to annotate that the flight conducted was a community service flight in their personal logbook.

These changes will allow CASA to conduct ongoing identification and monitoring of risks associated with community service flights to be able to manage and control those risks.

CASA has also promoted its updated human factors education package to the industry broadly, including the community service flight sector, and refers to it on the community service flight landing page on its website. CASA also intends to release targeted guidance information to further assist the community service flight sector in the coming months.

Safety message

Organisations conducting community service flights and their pilots should be aware of the additional operational risks present. It is important that organisations have appropriate operational controls in place, and ensure pilots have access to guidance and education regarding the risks, to enable them to make objective decisions.

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The occurrence

Context

Safety analysis

Findings

Safety issues and actions

Sources and submissions

Appendix A – Data analysis methods

Appendix B – Additional data

Appendix C – Angel Flight occurrence summaries

Australian Transport Safety Bureau

Preliminary report

Published: 1 August 2017

At about 0800 Central Standard Time[1] on 28 June 2017, a SOCATA TB-10 aircraft, registered VH-YTM (YTM), departed Murray Bridge Airport for Mount Gambier Airport, South Australia.

Position and altitude information obtained from OzRunways[2] showed that the aircraft’s inbound path (Figure 1) from Murray Bridge was straight and at an altitude of about 4,500 ft. At about 42 km north-north-west of Mount Gambier Airport, the altitude decreased and there was a significant deviation from the direct route. Several manoeuvres were then made at low altitude in the vicinity of the airport, including a possible attempted landing on runway 36. After a series of low level turns, the aircraft landed on runway 29 at about 1008.

Figure 1: Approach path of VH-YTM showing the initial deviations from the direct flight path on the left, and the series of low level turns prior to landing on runway 29 on the right

Figure 1: Approach path of VH-YTM showing the initial deviations from the direct flight path on the left, and the series of low level turns prior to landing on runway 29 on the rightSource: Google Earth and OzRunways, annotated by ATSB

The pilot then refuelled the aircraft and boarded two passengers, to conduct a flight to Adelaide arranged by the charity Angel Flight Australia.[3] The flight was to be conducted as a private flight under visual flight rules (VFR).

Witnesses in the vicinity of Mount Gambier Airport reported fog in the area at the time of landing and take-off. Similarly, CCTV footage showed the fog and reduced visibility conditions at the airport at the time of landing and take-off.

OzRunways data (Figure 2) and CCTV footage showed the aircraft took off from runway 24 at about 1020. Just after take-off, YTM veered to the left of the runway, at an altitude of approximately 300 ft above mean sea level (AMSL). The aircraft reached a maximum altitude of about 500 ft, 45 seconds after take-off. The last recorded information, about 65 seconds after take-off, showed the aircraft at an altitude of 400 ft.

A number of witnesses heard a loud bang, consistent with the aircraft’s impact with terrain.

Figure 2: Flight path of VH-YTM after departing runway 24 at Mount Gambier Airport, where each vertical line represents 5 seconds, and an indication of the wreckage location

Figure 2: Flight path of VH-YTM after departing runway 24 at Mount Gambier Airport, where each vertical line represents 5 seconds, and an indication of the wreckage locationSource: Google Earth and OzRunways, annotated by ATSB

Transmissions from the pilot of YTM on approach and take-off were recorded on the common traffic advisory frequency for Mount Gambier Airport. However, no emergency call was recorded. The aircraft was not equipped with a flight data recorder or cockpit voice recorder, nor was it required.

Minutes after impact the aircraft was found by witnesses passing the accident site, and emergency services responded to the scene shortly thereafter. The aircraft wreckage was located 212 m south of the last recorded position, just over 2 km from the departure runway (Figure 2). The pilot and two passengers were fatally injured and the aircraft destroyed.

On-site examination of the wreckage and surrounding ground markings (Figure 3) indicated that the aircraft impacted terrain at approximately 30° from vertical, in an inverted attitude. The engine and propeller were located at the initial impact point. The fuselage and remainder of the aircraft had detached from the engine at the firewall, and came to rest in an upright position about 10 m beyond the engine, with the tail and wings attached. The wings had sustained significant impact damage to the leading edge. A strong smell and presence of fuel was evident at the accident site, however there was no evidence of fire. The aircraft did not have an emergency locator transmitter fitted, nor was it required. A portable locator beacon was found in the cockpit, but had not been activated.

Figure 3: Accident site looking north-west, showing the engine and propeller location alongside the left and right wing impact marks, about 10 m from the main wreckage, which is upright and facing in a north-north-easterly direction

Figure 3: Accident site looking north-west, showing the engine and propeller location alongside the left and right wing impact marks, about 10 m from the main wreckage, which is upright and facing in a north-north-easterly directionSource: ATSB

Several components and documentation were removed from the accident site for further examination by the ATSB.

The investigation is continuing and will include examination of the following:

  • recovered components and available electronic data
  • aircraft maintenance documentation
  • weather conditions
  • pilot qualifications and experience
  • coordination and planning of the charity flight
  • the use of private flights for the transfer of passengers for non-emergency medical reasons
  • similar occurrences.

____________
The information contained in this web update is released in accordance with section 25 of the
Transport Safety Investigation Act 2003 and is derived from the initial investigation of the occurrence. Readers are cautioned that new evidence will become available as the investigation progresses that will enhance the ATSB's understanding of the accident as outlined in this web update. As such, no analysis or findings are included in this update.

 

__________

  1. Central Standard Time (CST) was Co-ordinated Universal Time (UTC) +9.5 hours.
  2. OzRunways is an electronic flight bag application that provides navigation, weather, area briefings and other flight planning information.
  3. Angel Flight Australia is a charity that coordinates non-emergency flights to assist people to access specialist medical treatment.

Safety Issues

Go to AO-2017-069-SI-01 - Go to AO-2017-069-SI-02 - Go to AO-2017-069-SI-03 - Go to AO-2017-069-SI-04 -

Angel Flight Australia consideration of commercial flights

Angel Flight did not consider the safety benefits of commercial passenger flights when suitable flights were available.

Safety issue details
Issue number: AO-2017-069-SI-01
Who it affects: All passengers on community service flights conducted by Angel Flight Australia
Status: Safety action pending

Insufficient organisational risk controls implemented by Angel Flight Australia

Angel Flight had insufficient controls in place, and provided inadequate guidance to pilots to address the additional operational risks associated with community service flights.

Safety issue details
Issue number: AO-2017-069-SI-02
Who it affects: All passengers on community service flights conducted by Angel Flight Australia
Status: Safety action pending

Availability of safety information to Angel Flight Australia

There were limited opportunities for Angel Flight to be made aware of any safety related information involving flights conducted on its behalf.

Safety issue details
Issue number: AO-2017-069-SI-03
Who it affects: All pilots conducting community service flights on behalf of Angel Flight Australia
Status: Adequately addressed

Regulatory differentiation between community service flying and private operations

CASA did not have a system to differentiate between community service flights and other private operations, which limited its ability to identify risks. This hindered the Civil Aviation Safety Authority's ability to manage risks associated with community service flights.

Safety issue details
Issue number: AO-2017-069-SI-04
Who it affects: All passengers on community service flights conducted by Angel Flight Australia
Status: Adequately addressed
General details
Date: 28 June 2017   Investigation status: Completed  
Time: 1020 CST   Investigation level: Complex - click for an explanation of investigation levels  
Location   (show map): 2 km south-west of Mount Gambier Airport   Investigation phase: Final report: Dissemination  
State: South Australia   Occurrence type: Collision with terrain  
Release date: 13 August 2019   Occurrence category: Accident  
Report status: Final   Highest injury level: Fatal  

Aircraft details

Aircraft details
Aircraft manufacturer S.O.C.A.T.A.-Groupe Aerospatiale  
Aircraft model TB-10  
Aircraft registration VH-YTM  
Serial number 1518  
Operator Private Pilot  
Type of operation Private  
Sector Piston  
Damage to aircraft Destroyed  
Departure point Mt Gambier, South Australia  
Destination Adelaide, South Australia  
Last update 13 August 2019