Aviation safety investigations & reports

Collision with terrain involving Lockheed EC130Q, N134CG, 50 km north-east of Cooma-Snowy Mountains Airport (near Peak View), New South Wales, on 23 January 2020

Investigation number:
AO-2020-007
Status: Active
Investigation in progress

Preliminary report

Preliminary report published 28 February 2020

Sequence of events

On 23 January 2020, at about 1205 Eastern Daylight-saving Time,[1] a Lockheed EC130Q (C‑130) aircraft, registered N134CG and contracted to the New South Wales (NSW) Rural Fire Service, departed Richmond RAAF Base, NSW. The crew had been tasked with a fire retardant drop over the ‘Adaminaby Complex’ bush fire.

After approaching the Adaminaby complex fire, the drop was unable to be completed and the aircraft was diverted to a secondary tasking, to drop retardant on the ‘Good Good’ fire (Figure 1). Witnesses reported seeing the aircraft complete a number of circuits, prior to completing the retardant drop. The drop was conducted on a heading of about 190°, at about 200 ft above ground level, with a drop time of approximately 2 seconds. The crew released about 1,200 US gallons (4,500 L) of fire retardant during the drop.

Figure 1: Flight path of N134CG (white)

Figure 1: Flight path of N134CG (white). Source: Google Earth, Aireon and RFS tracking data, annotated by the ATSB

Source: Google Earth, Aireon and RFS tracking data, annotated by the ATSB

Witness videos taken of the aircraft leading up to the accident showed a number of passes conducted at varying heights prior to the retardant drop. Following the retardant drop (Figure 2), the aircraft was observed to bank left, before becoming obscured by smoke[2] after about 5 seconds. A further 15 seconds after this, the aircraft was seen flying at a very low height above the ground, in a left wing down attitude. Shortly after, at about 1316, the aircraft collided with terrain and a post-impact fuel-fed fire ensued. The three crew were fatally injured and the aircraft was destroyed.

Figure 2: Overview of the drop zone (red fire retardant) and accident location

Figure 2: Overview of the drop zone (red fire retardant) and accident location.
Source: ATSB

Source: ATSB

A review of the Airservices Australia audio recording of the applicable air traffic control frequency found no distress calls were made by the crew prior to the impact.

Wreckage and impact information

The accident site was located on slightly sloping, partially wooded terrain, about 50 km north-east of the Cooma-Snowy Mountains Airport. The wreckage trail (Figure 3) was approximately on a heading of 100°, with the initial impact at an elevation of about 3,440 ft above mean sea level.

The ATSB’s on-site examination of the wreckage, damage to the surrounding vegetation, and ground markings indicated that the aircraft initially impacted a tree in a left wing down attitude, before colliding with the ground. The post-impact fuel-fed fire destroyed the aircraft. The examination also found that an emergency dump of the fire retardant had not been activated.

The engines, propellers, and several other components have been retained by the ATSB for further examination.

Figure 3: Aircraft impact and wreckage

Figure 3: Aircraft impact and wreckage.
Source: ATSB

Source: ATSB

Aircraft information

The Lockheed C-130 is predominantly an all-metal, high-wing aircraft, largely designed for military operations. The aircraft was manufactured in 1981 and was powered by four Allison T56-A-15 turboprop engines, fitted with Hamilton Sundstrand 54-H60-91 four blade propellers. Previously owned by the United States Navy, the aircraft was re-purposed for firefighting activities and registered as N134CG in 2018 (Figure 4). The modifications included the installation of an avionics package and firefighting tank system known as Retardant Aerial Delivery System XXL (RADS).

The RADS included a 4,000 US gallons (15,000 L) tank system located within the aircraft’s fuselage. The system was capable of delivering discrete quantities of retardant, dependent on the duration that the doors remained open. It was controlled from the cockpit, with drop controls located on both the pilot and copilot yokes. The system also included an emergency dump switch, which, when activated, fully opened the doors and jettisoned the load. The doors remained open until the RADS was reset by the crew.

N134CG arrived in Australia in November 2019, but had previously operated in the country during the 2018‑2019 fire season. The aircraft was designated as a ‘large air tanker’.

Figure 4: N134CG

Figure 4: N134CG. Source: Coulson Aviation

Source: Coulson Aviation

Meteorological information

A Bureau of Meteorology graphical area forecast, issued at 0924 and valid for the time of the flight, forecast moderate mountain wave activity above 3,000 ft (above mean sea level) in the area of operation from Richmond to Cooma, and included the Adaminaby and Good Good fire grounds. A SIGMET[3] issued at 0947 forecast severe turbulence below 10,000 ft.

The aerodrome forecast for the Cooma-Snowy Mountains Airport[4] was amended at 0948, and indicated wind speeds of 30 kt, gusting to 48 kt, with a mean wind direction of 320°. It also included blowing dust and visibility of 2,000 m, with severe turbulence below 5,000 ft above ground level.

The weather observations recorded at the airport about 11 minutes prior to the accident, indicated a wind speed of 25 kt, gusting to 39 kt, from a direction of 320°, with visibility reduced to 6,000 m.

Cockpit voice recorder

Cockpit voice recorders (CVR) are designed on an endless loop principle, where the oldest audio is continuously overwritten by the most recent audio. The CVR fitted to the aircraft was a Universal model CVR-30B, part number 1603-02-03, serial number 1541. This model of recorder used solid-state memory to record cockpit audio and had a recording duration of 30 minutes.

The CVR was recovered from the aircraft and transported to the ATSB’s technical facility in Canberra, Australian Capital Territory, on 25 January 2020 for examination and download. The CVR was successfully downloaded, however, no audio from the accident flight had been recorded. All recovered audio was from a previous flight when the aircraft was operating in the United States.

Further investigation

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

  • engine, gearbox and propeller component examinations
  • aircraft maintenance history
  • aircraft performance and handling characteristics
  • impact sequence
  • analysis of numerous witness reports
  • review and analysis of the available recorded data, including witness videos, aircraft tracking data, audio recordings and any onboard systems
  • review and analysis of environmental influences
  • the crew's qualifications, experience and medical information
  • the nature of aerial fire-fighting operations
  • operating policies and procedures
  • exploring the possible reasons why the CVR did not record the accident flight
  • similar occurrences.

The ATSB will continue to consult with the engine and airframe type certificate holders. Accredited representatives from the United States National Transportation Safety Board (NTSB) have been appointed to participate in the investigation.

Acknowledgments

The ATSB acknowledges the support of the NSW Police Force, NSW Rural Fire Service, NSW Fire and Rescue, the Australian Defence Force, and those involved with facilitating safe access to an active fire ground and supporting the ATSB’s on-site investigation team.

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The information contained in this preliminary report 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 preliminary report. As such, no analysis or findings are included.

 

_________

  1. Eastern Daylight-saving Time (EDT): Coordinated Universal Time (UTC) + 11 hours.
  2. From the video, it was unclear if the aircraft flew behind the smoke or entered the smoke.
  3. Significant meteorological information (SIGMET): a weather advisory service that provides the location, extent, expected movement and change in intensity of potentially hazardous (significant) or extreme meteorological conditions that are dangerous to most aircraft, such as thunderstorms or severe turbulence.
  4. The Cooma-Snowy Mountains Airport has an elevation of 3,106 ft.

Initial summary

Initial summary 23 January 2020

The ATSB is investigating the collision with terrain of a Lockheed EC130Q Hercules Large Air Tanker, registration N134CG, near Peak View, New South Wales, on 23 January 2020.

While conducting fire control operations, the aircraft collided with terrain after completing a fire retardant drop. The three flight crew on board were fatally injured, and the aircraft was destroyed.

The ATSB has deployed a team of transport safety investigators with experience in aircraft operations, maintenance and data recovery to the accident site, to begin the evidence collection phase of the investigation, including conducting site mapping and identifying aircraft components for recovery for examination at specialist technical facilities.

As part of the investigation, ATSB investigators will also analyse available recorded data, review weather information, aircraft maintenance and flight crew records, and interview witnesses.

Should any safety critical information be discovered at any time during the investigation, the ATSB will immediately notify operators and regulators so appropriate and timely safety action can be taken.

A final report will be published at the conclusion of the investigation.

General details
Date: 23 January 2020   Investigation status: Active  
Time: 1316 AEDT   Investigation level: Systemic - click for an explanation of investigation levels  
Location   (show map): near Peak View   Investigation phase: Evidence collection  
State: New South Wales   Occurrence type: Collision with terrain  
Release date: 28 February 2020   Occurrence category: Accident  
Report status: Preliminary   Highest injury level: Fatal  
Anticipated completion: 3rd Quarter 2021    

Aircraft details

Aircraft details
Aircraft manufacturer Lockheed Aircraft Corp  
Aircraft model EC130Q  
Aircraft registration N134CG  
Serial number 382-4904  
Operator Coulson Aviation  
Type of operation Aerial Work  
Sector Turboprop  
Damage to aircraft Destroyed  
Departure point Richmond, New South Wales  
Destination Firefighting operations north-east of Cooma, NSW  
Last update 20 July 2020