07/03/2012 14:43 GMT | Updated 07/05/2012 10:12 BST

British Tourists Killed In Cameroon Swamp Plane Crash Were 'Unaware Of Nose-Dive'

A group of passengers travelling on an ill-fated plane may not have known when it began to nose-dive and then crashed into a swamp in Cameroon, an inquest has heard.

A total of 114 passengers were killed on the Kenya Airways flight, including four Britons: Anthony Mitchell, 39; Adam Stewart, 43; his wife Sarah Stewart, 50; and 45-year-old Stuart Claisse.

The plane crashed just three miles from the end of the Douala runway from which it had taken off for Nairobi, Kenya on May 5 2007.

The Boeing 737-800, which was only six months old, crashed in the mangrove swamp at midnight.

Anthony Mitchell (second left) with (left to right) his son Tom, wife Catherine and daughter Rose

At an inquest into the four deaths at Lincoln Coroner's Court today, Marcus Cook, an inspector at the Air Accidents

Investigation Branch and himself a pilot, told the families of those killed that there was a "strong possibility" their relatives may not have been aware when the plane went into a "spiral dive".

"You're sitting at the back. It's dark. You can't see anything. You've no cockpit instruments," he said.

"They may have felt the roll."

Mr Cook told the inquest the plane crashed shortly after take-off when it banked, or rolled, too far to the right. He said that just after the plane was airborne it appears the captain was not controlling it.

"About 15 seconds later, for no real reason, it appears that all input into the flight control by the captain ceases, and it ceases for about 55 seconds," he said.

"At this point the airplane is about 1,000ft above the ground."

Mr Cook said there was no record of the autopilot being engaged at this point and there was a chance that it had been selected but not successfully engaged.

Coroner Stuart Fisher asked him: "So for clarity: the plane is in flight at 1,000ft, pilots are not flying the aircraft and it's not being flown on autopilot?"

Mr Cook answered: "Not at this point."

He told the inquest the plane continued to bank to the right - aircraft tend to drift to the right after take-off but can be corrected simply by the captain steering it back on track - until a "bank angle" warning sounded once it had gone over a 40 degree angle.

The autopilot was then successfully engaged, he said, and the pilot, who has not yet been named in the inquest, took action to try to counter the roll.

However, all of his attempts such as steering and using the plane's rudders simply increased the roll to the right.

Mr Cook went on: "At this point bank angle is 50 degrees and increasing. In my eyes that was still recoverable.

"The bank angle then increases and the nose drops below the horizon. The airplane then enters a spiral dive."

At this point the pilot says "we're crashing", Mr Cook told the inquest.

He told families he believed that the pilots may have become spatially disorientated and distracted if they were focusing on weather reports or discussing matters between themselves, and may not have believed what the plane's instruments were telling them if they had not been monitoring them.

The inquest also heard that post-mortem examination reports in all four cases recorded a cause of death as multiple injuries sustained from an aircraft crash.

The wreckage of the plane was located after more than 40 hours of searching dense rainforest in drenching rain and thick fog.

The pronouncement that there were no survivors was made after the water-filled crater left by the plane was examined.

Kenya Airways confirmed it was found 12 miles south-east of the Cameroon coastal city of Douala, along the planned

flight path.

Mr Mitchell was a journalist with the Associated Press news agency, based in Nairobi.

He had been on assignment in the region and had contacted his family before boarding the flight to tell them he was heading home.

Mr Mitchell, who was originally from London, lived in Nairobi with his wife, Catherine, and their children, Tom and Rose.

Mrs Stewart was chief financial officer for South African mobile phone giant MTN's Cameroon operations and was travelling to a business meeting in South Africa.