Preliminary report released about crash of Air Tanker 134

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

The accident occurred January 23, 2020 in Australia

Today the Australian Transport Safety Bureau released a preliminary report about the crash of Air Tanker 134, an EC-130Q, that occurred January 23, 2020 while fighting a bushfire in New South Wales. The location was 50 km north-east of Cooma-Snowy Mountains Airport (near Peak View). All three members of the crew perished, First Officer Paul Clyde Hudson, Captain Ian H. McBeth, and Flight Engineer Rick A. DeMorgan Jr.

Below is the complete text of the 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.

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. 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. 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. 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.

_________

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.

_________

Eastern Daylight-saving Time (EDT): Coordinated Universal Time (UTC) + 11 hours.
From the video, it was unclear if the aircraft flew behind the smoke or entered the smoke.
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.
The Cooma-Snowy Mountains Airport has an elevation of 3,106 ft.

Go to Source to read more

Author: Bill Gabbert
The post Preliminary report released about crash of Air Tanker 134 appeared first on Fire Aviation.