A Romanian stowaway has survived a 97-minute flight from Vienna to Heathrow while clinging to the retracted undercarriage of the aeroplane.

The 20-year-old man, who told British authorities that he crawled "under the wire" of the Vienna airport's perimeter fence on Sunday evening, climbed into the undercarriage of a private Boeing 747 belonging to a high-ranking sheik from the United Arab Emirates.

A spokesman for the Metropolitan police said the man, who has not been identified by the Romanian embassy in London or the Romanian foreign ministry in Bucharest, was arrested and cautioned for the offence of being a stowaway and questioned about entering Britain without a passport before being released.

Paramedics checked him at Heathrow after his arrest but he had suffered no injuries. It is thought that he withstood temperatures around -41C and a severe lack of oxygen during the journey, before falling to the ground when the aircraft landed.

A spokesman for the Civil Aviation Authority (CAA) said the man was "very lucky" to be alive. He said: "It's not unheard of for people trying to escape from a country to use this method.

"If they do stow away in the wheel wells, then there are a number of things that can happen to them. If they don't find the right part to stow away, they can be crushed when the undercarriage comes up. Because of the altitude and temperatures during the flight, there is a severe risk to them through exposure and lack of oxygen.

"If that doesn't kill them, then they could be unconscious when the aircraft descends, and that can mean that when the under-carriage opens again, they will fall out."

Austria media reported the stowaway may have survived as the aircraft flew "well below 10,000 metres (32,808ft)" due to bad weather.

"Due to specific circumstances of this flight, he is lucky to have survived, because survival in these cases in quite rare," added Sidney Dekker, a professor of flight safety at the School of Aviation at Sweden's Lund University.

"But on another level, this incident also illustrates the absurdities of security checks." Vienna airport spokesman, Paul Kleemann, said they were investigating how the man was able to enter a secure area.

Vienna airport police chief Leo Lauber told the Evening Standard: "He aimed for any jet it would seem, not one in particular. After wriggling under the fence he headed for the aircraft nearest to the fence. He had no idea where it was going to. Initial inquiries seem to indicate he wanted to go abroad to find work."

A Metropolitan police spokesman said: "Police were alerted at 7.37pm on Sunday June 6 re: a suspected stowaway on a private aeroplane that had landed at Heathrow.

"A 20-year-old Romanian national was arrested for stowing away on an aircraft, contrary to Article 143 and 241(6) of and Part B of Schedule 13 to the Air Navigation Order 2009."

He added: "It is alleged that he had stowed himself in the rear wheel compartment of the aircraft at Vienna Airport."

Britain has restrictions on the number of Romanians working in the country, even though both nations are in the EU. There have been similar stowaway attempts in recent years, but most have resulted in death.

In February, a man's body was found inside the landing gear compartment of a Delta Air Lines plane after it landed in Tokyo from New York. The body had no visible injuries except frostbite and authorities said that he may have died of hypothermia.

In 2007, another man was found dead in the nose gear wheel well of a United Airlines flight that arrived in San Francisco from Shanghai.

A stowaway hid in the undercarriage of a jumbo jet and survived temperatures of -41c at 25,000ft during a free flight into Britain.

The jobless Romanian crouched in the rear-wheel compartment during an extraordinary 800-mile trip from Vienna to London on a Boeing 747 owned by the Dubai royal family.

Airport officals say the man could easily have been crushed by the plane's wheels or killed by a lack of oxygen and was 'incredibly lucky' to be alive.

When the privately owned Boeing landed at Heathrow, the 20-year-old stowaway tumbled on to the runway and was arrested by security staff.

He said he had come to Britain to find work, was examined by paramedics but incredibly suffered only a few bruises and was fit enough to be interviewed by police and immigration officials.

Less than 24 hours later, he was released after accepting a police caution for being a stowaway and - because he is an EU national and proved his identity - was allowed to stay in Britain.

A police source said: 'The plane would normally have flown at 37,000ft which would have killed him but it was flying lower because of thunder-storms.

Wheel housing: Many desperate immigrants have used the landing gear cavity to hide, but almost all perish in the -40C temperatures at high altitude

'This, and the fact it was a short-haul flight, meant he survived. He's had a free flight and been released for his troubles. Welcome to England.'

The Romanian reportedly slipped under a perimeter fence at Vienna Airport on Sunday evening and made his way to a private jet owned by the Dubai royal family.

He told police he climbed into the wheel compartment of the plane, which took off at about 7pm UK time. One hour and 37minutes later, it landed at Heathrow.

Sources said the man fell or jumped soon after the aircraft touched down and was arrested at 8.48pm for stowing away on an aircraft, contrary to Article 143 of the Air Navigation Order 2009, which carries a maximum sentence of a £2,500 fine.

He was taken to Heathrow police station but because he was apparently of previous good character, he was given a police caution and released from custody at 2.47pm on Monday.

The man was carrying ID and immigration officials were satisfied he was Romanian and entitled to stay. Home Office sources confirmed there were no immigration issues and that the UK Border Agency was not seeking to deport him.
fence

But the plot thickened last night after a spokesman for the Romanian Embassy in London said Scotland Yard was trying to find him.

The official told the Mail: 'They called after his release from custody to say there were some outstanding questions, and asked us whether we had had heard from him. We have no idea where he is.'

Speculation was rising last night that he may be seeking work at the Olympic Stadium in East London, where hundreds of Romanian construction workers are employed.

The Sheikh who owns the plane has reportedly threatened legal action against Vienna airport officials.

Vienna airport spokesman Peter Kleemann said: 'This is the first time we have ever had a case like this.' He said the man said 'he had had enough of Vienna and wanted to go somewhere else where he might find work'.

Vienna police spokesman Leo Lauber added: 'We are investigating, this is a high security area, we don't know how this could have happened. He claims he just climbed under the fence and then found a place on board the first aircraft he saw.'

Mr Lauber admitted the ten miles of fencing around the airport perimeter are not constantly patrolled.

The Austrian interior ministry begun an inquiry into the security breach. But a spokesman added that individual airlines should be responsible for their own security. A spokesman for Britain's Civil Aviation Authority said the man was very lucky to be alive.

Some stowaways have died after falling from planes when the wheels are lowered on approach to landing.

In October 1996, a couple in a pub garden spotted a body falling from a DC9 over Richmond in South-West London as it approached Heathrow.

Vijay Saini, 19, plunged 2,000ft. A post mortem examination revealed that he was already dead when he fell. His brother Pardeep, 22, survived the ten-hour journey.