In the recent case of Robinson Helicopter v McDermott the High Court considered the personal injury liability of the manufacturer of a helicopter that suffered a defect, which resulted in a fatal crash. The Court had to determine whether the maintenance manual, published by the manufacturer, gave sufficient instruction for identifying the defect.


In May 2004 a helicopter inspecting fences at a cattle station in Queensland crashed. The crash resulted in the death of the pilot and serious injuries to the passenger, McDermott. The cause of the crash was a failure in one of the bolts securing the forward flex plate of the helicopter. The flex plate and bolts had been removed and reassembled in February 2004. During reassembly, the bolts were not tightened to the requisite degree (the Defect). The helicopter was subject to two “100 Hourly” inspections (the Inspections) by licenced maintenance engineers between reassembly and the crash.

McDermott commenced proceedings, alleging negligence, against the manufacturer of the helicopter, Robinson Helicopter (Robinson). The essential issue was whether the maintenance manual (the Manual) for the helicopter, prepared by Robinson, provided for an adequate procedure at the Inspections that would identify the Defect. The Manual provided for a seal of paint to be applied over the bolts that would break or misalign to indicate bolts had become loose. The Manual further required the engineer conducting the Inspections to “verify [the] security” of the flex plate.

First instance

At trial Lyons J found in favour of Robinson. His Honour held that the Manual was sufficient to convey to the engineers conducting the Inspections that it was necessary to check the seals on the bolts and, if they were missing, damaged or incomplete, tighten the bolt and apply a new seal.

His Honour also came to the conclusion, based on the evidence before him, that it was likely the seals were not applied to the bolts when the flex plate was reassembled. In the alternative, his Honour found that if the seals had been applied then they would have rotated shortly after the reassembly. If this was the case then the Defect should have been visible to the engineers conducting the Inspections in accordance with the Manual.

Queensland Court of Appeal

The Court of Appeal reversed the findings of Lyons J, by majority. McMurdo P and Wilson J held that the trial judge had erred in his findings as to the likely appearance of the bolts, stating that there was insufficient evidence to support this conclusion.

The majority also found that there was an error in the trial judge’s reasoning. This error was a purported inconsistency with the following two findings:

  • that it was likely the seals were not applied on the bolts upon reassembly of the flex plate; and
  • the weight of the evidence given by the engineers who conducted the Inspections is to be diminished because if they had correctly conducted the Inspections the condition of the seal would have indicated the bolt had come loose.

The majority reasoned that if the seals were not applied, then the evidence of the engineers could not be diminished as there were no seals to have indicated that the bolt had come loose.

The majority thereby concluded that the evidence did not support the trial judge’s conclusion as to the appearance of the bolts. This being so, it was possible for the Defect to have arisen despite the integrity of the seals being preserved. Because the Manual did not adequately make it clear that a visual inspection of the seals may not be sufficient, the majority found Robinson failed to discharge their duty of care.

Robinson appealed this decision to the High Court.

The High Court

The High Court unanimously overturned the decision of the Court of Appeal and found in favour of Robinson. The joint judgment of French CJ, Bell, Keane, Nettle and Gordon JJ held at [43] that:

[A] court of appeal should not interfere with a judge’s findings of facts unless they are demonstrated to be wrong by ‘incontrovertible facts or uncontested testimony’, or they are ‘glaringly improbable’ or ‘contrary to compelling inferences’. In this case, they were not.”

The plurality considered the different possibilities of the appearance of the bolt, and held that there was sufficient evidence for the trial judge to conclude that the seal was not applied during reconstruction of the flex plate. The Court found that it was accordingly open to the trial judge to find that if the Inspections were conducted in accordance with the Manual then the Defect would have been checked.

The Court also held that, contrary to the findings of the majority of the Court of Appeal, that there was no inconsistency between the two findings set out above. This was because the second finding was referring to Lyons J’s alternative conclusion that if the seals were applied, then the Defect would have been visible during the Inspections. Therefore, the High Court held that McDermott had not demonstrated that the Manual failed to discharge Robinson’s duty of care.

The High Court went on to consider causation, despite it being “strictly speaking, unnecessary”. The plurality held that even if the Court of Appeal was correct in finding that it was possible for the bolts to have loosened without breaking the paint seals, this would not have been sufficient to establish causation. This was because McDermott had not established that the possibility of this occurring was any more likely than the seal not being applied, or being applied and subsequently becoming misaligned. Therefore, any breach of duty by failing to provide for that possibility in the Manual could not be said to be causative of the crash.


This case emphasises the importance that appellant courts should place on findings of facts by a trial judge. The Court noted the “significant advantage” the trial judge had to hear the oral evidence provided by the witnesses, and considered it relevant that the trial “judge alone had the opportunity to consider all of the evidence in its totality and to reflect at length on its interaction”.

For manufacturers of complex goods, such as helicopters, this case confirms that a defect resulting in personal injury does not necessarily mean liability. The procedure for inspections set out by Robinson in the Manual was sufficient to fulfil their obligations with respect of the Defect.

Finally, the High Court’s comments on causation serve to remind us that if the manufacturer has breached their duty, it must be shown that it was the manufacturer’s breach that caused the injury. If there are a number of equally likely causes of the injury then the manufacturer will not incur liability. Therefore, the plaintiff will instead have to attempt to recover his losses from the parties who reassembled the flex plate and conducted the Inspections – and failed to read the manual.