Australia: Heli-mustering accident leads to catastrophic spinal injury

Last Updated: 8 February 2016
Article by Andrew Tulloch

In brief - Helicopter pilot found not to have breached duty of care

In Cook v Modern Mustering Pty Ltd & Ors and Savage & Ors v Modern Mustering Pty Ltd & Ors [2015] NTSC 82, a passenger who sustained serious spinal injuries in a helicopter accident failed to prove that the pilot had breached his duty of care and did not show that flying below 500ft had been a breach in the pilot's duty which caused his injuries.

Injured passenger receives workers' compensation payout, brings common law claim

The complete loss of power in a Robinson R22 helicopter, which prior to the accident was cruising at about 250ft above ground, led to a passenger sustaining multiple catastrophic spinal injuries.

The passenger, Mr Cook, who had been engaged as a cattle "spotter" as part of a mustering operation, received a lump sum payment of $10.5 million in work health proceedings. However, he then brought a common law claim against the owner of the helicopter, the holder of the Air Operator's Certificate (AOC) and the pilot in the Supreme Court of the Northern Territory in Cook v Modern Mustering Pty Ltd and Ors.

Court considers duty of care and whether breach of duty was causative of injuries

In a judgment of Justice Kelly delivered on 10 December 2015, consideration was given to issues of breach of duty of care and whether that breach of duty was causative of Mr Cook's injuries.

It was alleged that the pilot negligently flew below 500ft in breach of regulations, as at the time the helicopter was not engaged in aerial stock mustering operations, which was the basis upon which permission for low flying had been granted.

There was also an issue of the meaning of "aerial stock mustering operations" and whether Mr Cook, who was not employed by the owner of the helicopter or the holder of the AOC, was a "crew member". Low flying was only permitted if "persons other than crew members are not carried". (See Civil Aviation Regulations 1988, regulation 157(4)).

Helicopter loses power following cattle mustering operation

On the day of the accident, Mr Cook had himself first flown a gyrocopter and done some mustering. He then returned to the camp to board the helicopter and to act as a cattle "spotter" for the pilot and to provide guidance to him regarding the mustering operation. After some further mustering, the helicopter was returning to the camp to enable Mr Cook to operate the gyrocopter once again when the loss of power occurred.

Despite an attempted autorotation, the helicopter tail rotor clipped a tree and the helicopter landed on its skids without its tail, slid forward for some distance and tipped forward until the rotor hit the ground and the helicopter tipped over landing on the passenger side.

While Mr Cook was very seriously injured, the pilot was uninjured.

Definition of "crew member" considered by court

The relevant regulations define "crew member" to mean a person assigned by an air operator for duty on an aircraft.

It was argued that as Mr Cook was employed by a different company to the pilot and holder of the AOC, he was not a crew member and accordingly it was not permissible for the helicopter to fly lower than 500ft.

This argument was rejected as, if correct, the judge considered the helicopter could never fly below 500ft with a spotter on board. While that may be overstating the consequence of this finding, it nevertheless seemed that the judge looked at the overall nature of the operation and how it was controlled by those aboard to determine that Mr Cook was a "crew member".

Judge finds that helicopter was engaged in aerial stock mustering operations at time of accident

The plaintiff maintained that as the purpose of the return flight was to enable Mr Cook to disembark and board the gyrocopter, the helicopter was not engaged in aerial mustering operations at the time of the accident.

The judge did not consider that this made sense as, if correct, the pilot would be changing regulatory requirements mid-flight depending on the particular activities in which he was engaged. He also noted that only minutes before the accident mustering operations were being undertaken. He concluded accordingly that the helicopter was engaged in aerial stock mustering operations when the accident occurred and was not in breach in flying below 500ft.

Judge refers to Shirt calculus in determining negligence

As to the issue of the breach of duty of care, the judge considered the "Shirt calculus" as stated by Justice Mason in Wyong Shire Council v Shirt [1980] HCA 12 where he said:

In deciding whether there has been a breach of the duty of care, the tribunal of fact must first ask itself whether a reasonable man in the defendant's position would have foreseen that his conduct involved a risk of injury to the plaintiff or to a class of persons including the plaintiff. If the answer be in the affirmative, it is then for the tribunal of fact to determine what a reasonable man would do by way of response to the risk. The perception of the reasonable man's response calls for a consideration of the magnitude of the risk and the degree of the probability of its occurrence, along with the expense, difficulty and inconvenience of taking alleviating action and any other conflicting responsibilities which the defendant may have. It is only when these matters are balanced out that the tribunal of fact can confidently assert what is the standard of response to be ascribed to the reasonable man placed in the defendant's position (at [14]).

He also referred to other decisions including that of Gleeson CJ in New South Wales v Fahy [2007] HCA 20 and noted that the relevant risk was that of injury to Mr Cook if there was a sudden loss of power or mechanical failure. There was a lack of evidence as to the probability of the occurrence and only limited evidence as to whether the height of the helicopter increased or decreased the risk and its likely consequences.

In the circumstances, the court found that the plaintiff had not proved on the balance of probabilities that the defendant was in breach of a duty of care to the plaintiff. It was also noted that, even if in breach of the duty of care in flying below 500ft, the plaintiff had not shown that this was a cause of the injury.

Accordingly, the plaintiff's claim failed.

Heli-mustering industry will appreciate judge's decision

The judgment seems a sensible one and it seems reasonable to avoid the imposition of somewhat artificial divisions in the purpose of flight to determine the applicable regulations for flight operations. Those engaged in the heli-mustering industry would recognise the common sense of that outcome.

While it may be regrettable that such a seriously injured person was not entitled to compensation at common law, he nevertheless had already received very substantial damages by way of workers' compensation.

The decision should be of particular interest to those involved in the use of aircraft including helicopters in the agricultural industry.

Andrew Tulloch
Colin Biggers & Paisley

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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Andrew Tulloch
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