The leader of the expedition on which a boy was killed by a polar bear has told an inquest the group had been supplied with an incomplete tripwire system.
The missing materials meant they had to set it up in a triangle formation rather than the advised rectangular shape, 31-year-old Michael Reid said.
He explained that his group also had to improvise using a paper clip to modify the trigger system because the brass fittings were missing.
He said: "The tripwire system in base camp worked inconsistently, the system that we tested at the ice-climbing camp on our first or second night out from the base camp operated 100% when we tested it."
The leader of a schools expedition on which a boy was killed by a polar bear has told an inquest a bear watch was not held on the night of the attack because it would have left the team tired and vulnerable to cold-related illness the next day.
Michael Reid, known as Spike, told the hearing into the death of 17-year-old Horatio Chapple that he wrestled the bear after a rifle failed to fire.
It was then shot dead with a second rifle, by which point lethal blows had been administered to the Eton pupil's head and upper body.
The boy's parents said they examined a risk assessment document with Horatio before he left - adding they "would not have let him go" on the Arctic expedition without believing he would be properly protected.
However, the inquest heard that there was in fact a shortage of trip wires, mines and pen flares available to the young explorers, while Reid told the inquest that his rifle failed to fire upon the attack.
Mr Chapple said the risk assessment also suggested that a bear watch would take place at the camp.
A trip leader who shot dead a polar bear on a schools expedition has told an inquest his rifle failed to fire when the creature began attacking the group.
Michael Reid or 'Spike' from Plymouth, Devon said he was awoken by several people shouting "bear attack". He then grabbed the group's rifle and left his tent.
I cocked the rifle, took aim, aimed it carefully as I didn't want to shoot the YE, although it was close I didn't want to injure the [young explorers] or worse.
So I took a carefully aimed shot at the bear in the chest area of the bear but the rifle didn't fire. I cocked the rifle again and took another attempt at an aimed shot at the bear.
I do not know why this failure was happening and so I carried on this until the magazine was empty.
He said the bear then attacked him, before he grabbed his own rifle and killed the bear "as it was attacking someone else".
The trip leader of an expedition in which a 17-year-old boy was mauled to death by a polar bear has told an inquest how he wrestled with the predator as it attacked him after his rifle failed to fire.
Horatio Chapple was on an adventure holiday to the remote Svalbard islands in August 2011 with the British Schools Exploring Society (BSES) when he died.
The Eton pupil, from Salisbury, Wiltshire, was sleeping in his tent when the bear went on the rampage, inflicting fatal injuries to his head and upper body.
Michael Reid, known as Spike, from Plymouth, Devon, told the Salisbury inquest: "I remember the bear biting my head and I thought the weakest part is the eyes so I tried to take out the eyes with my fingers, but was unsuccessful."
Four others were hurt before the bear was eventually shot dead at the camp site, where the group, known as Chanzin Fire, had been staying.
Parents of a student killed by a polar bear during a school trip to Norway said today they thought he would be properly protected. 17-year-old Horatio Chapple, from Salisbury, died during an expedition to Svalbard. Another student was also injured before the expedition leader shot the bear dead.
Today, an independent report into Horatio's death found a trip wire system that was meant to scare off the animals wasn't good enough. Andrew Pate reports.
A polar bear ripped open the tent of a 17-year-old and dragged him out causing "mortal wounds" to his head, according to an independent report into the tragedy which happened during an Arctic adventure holiday.
Sir David Steel describes the incident during his report commissioned by the British Schools Exploring Society (BSES) into the death of Horatio Chapple in Svalbard, Norway.
Sir David said the attack, which "lasted no more than a few minutes" took place at about 7.30am on August 5, 2011, while the group, known as the Chanzin Fire, was still asleep.
In his report, Sir David criticises the reliance on a trip-wire warning system and advises the adoption of a bear watch and an overhaul of rifle training to prevent future tragedies.
He describes how the bear had approached through the north-western side of the trip-wire system but none of the warning mines had exploded.
In the report in which the names of the people have been redacted and replaced with coded letters, Sir David says: "The bear appears to have initially made its way to the tent containing E7, E3 and Horatio.
"It would appear likely that the bear must have ripped open the tent on Horatio's side. It then dragged Horatio out causing serious, indeed probably mortal wounds to his head.
Sir David said that a post mortem on Horatio concluded that his death was caused by "extensive soft tissue and bone injuries to the face and neck including destruction of the right facial artery".
He went on to praise the group members for their bravery.
He said: "All members including not least Horatio demonstrated great courage in the face of the attack which started while the camp was asleep.
"Likewise considerable presence of mind was shown by the uninjured members of the party in the aftermath of the attack in tending to the wounded and calling for help."
A bear watch should be put in place and less reliance placed on an "inconsistent" trip-wire system to prevent a further tragedy occurring, according to a report into the death of Horatio Chapple who was mauled to death by a polar bear during an adventure holiday.
High Court judge Sir David Steel was appointed by the British Schools Exploring Society (BSES) to conduct an independent inquiry into the death of the 17-year-old in August 2011 during the expedition to Svalbard, Norway.
The publication of the report has been delayed until today to coincide with the resumption of the inquest in Salisbury into Horatio's death.
In his conclusion, Sir David states that the expedition group, known as the Chanzin Fire, had followed the advice of the Norwegian authorities to use a trip-wire system to alert them to the presence of any polar bears.
But he said that this was inadequate as the warning would be too late and also the equipment used was defective.
Sir David also said that rifle training needed to be over-hauled for any future expeditions.
Sir David said that a bear watch would have been more effective as it would given the group more time to take measures to scare off the attacking bear.
He concluded: "In future a bear watch must become the norm for expeditions to Svalbard. There needs to be complete review of available trip-wire systems but they should be treated only as a secondary protection device. There needs to be a rigorous upgrade of rifle training."
The inquest into the death of a Wiltshire school boy, who was killed by a polar bear whilst on an expedition to Norway will begin today.
Horatio Chapple who was seventeen years old was killed by the bear in August 2011. Four others were injured when the animal got into their camp on the remote island of Svalbard.
A verdict of accidental death has been recorded at the inquest of Dorset sailor Andrew Simpson, who died during training for the America's Cup a year ago.
The Olympic gold medallist became trapped under the hull of his catamaran off San Francisco.
An inquest is due to open today into the death of Dorset sailor Andrew Simpson, who died during training for the America's Cup a year ago. The Olympic gold medallist became trapped under the hull of his catamaran off San Francisco.
A new sailing academy set up in honour of Andrew - known as Bart - was officially opened by his young sons earlier this month.