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An A-list actor is accused of having a mile-high fling, and a private plane company plans to launch chartered flights for romantic liaisons. But what exactly is the legality of this much fabled form of sexual indulgence?
It's a heady mix. There's the adrenaline of flying at 30,000 feet on the way to exotic shores and the frisson of illicit temptation. And maybe even the business class champagne.
Sex on an aeroplane - after the seatbelt lights are off, naturally - makes good reading for fans of blockbuster romance novels, but for some it is more than just a fantasy.
Janet Jackson and Richard Branson are self-confessed members of the "Mile-High Club" and Ralph Fiennes may have joined them.
Qantas is investigating whether the British actor had sex with a flight attendant on a flight from Darwin to Mumbai.
And entrepreneur Mike Crisp has launched a service on his six-seater private plane for couples who wish to get amorous for 90 minutes while being flown above the English countryside.
But is having sex on a plane legal?
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A Crown Prosecution Service spokesman says he is unaware of any prosecutions.
"The police would need to have a complaint and they would then investigate, and if they thought there was a case to answer then we would make a judgement on whether there's a case to bring forward."
What legislation is invoked depends on the circumstances, he says, and the police would look at the offence as a whole before deciding if laws such as outraging public decency have been infringed.
Getting frisky in the plane toilet could be a criminal offence, says travel lawyer Philip Banks, from the firm Irwin Mitchell. A person has committed an offence if they have sex in a lavatory to which the public has access, under section 71 of the Sexual Offences Act 2004.
Although there is no case law because the statute is so new, a plane's toilet could be interpreted as public under these terms, he says. The punishment is a six-month prison stint or a £1,000 fine.
Airlines can hand down their own punishments
Outraging public decency under common law could also be used, he says, if it was proven that at least one person may have seen the act.
But it may not be the UK laws which come into play, and which country's laws govern the offence may depend on the destination, the departure point, the country over which the offence is committed and the country where the plane is registered, says criminal lawyer Julian Young.
But despite the confessions of the rich and famous, there are few known instances of anyone getting caught.
Amanda Holt, 37, and David Machin, 40, were charged with outraging public decency in 1999 and subsequently fined after having sex in their seats on an American Airlines flight from Dallas to Manchester.
But generally getting caught red-handed is rare. One senior member of British Airways' cabin crew, who does not want to be named, says he's never encountered it in 10 years of flying. And a BA spokeswoman says they could call the police.
"It depends on the circumstances. In some cases it's better to have a quiet word because it could be better not to draw attention to other passengers who may not have noticed.
A self-confessed club member
"But if we believe they have broken the law or they've caused upset to other people and there's been a complaint, we could go to the police."
Although the airline cannot fine passengers, it can ban them for offensive behaviour, although she's unaware if this has ever happened.
There is nothing in transport law governing the matter of having sex on public transport. And the Civil Aviation Authority says there's nothing specific about it in aviation law - but there are other considerations.
"To comply with health and safety laws, they would have to be sitting with their seatbelts on for take-off and landing," a spokeswoman says.
And to join the club while strapped in would take some doing.
Add your comments on this story, using the form below.
It's not always in the toilet. On a flight home from India, my friend's flatmate simply waited 'til the lights went down and everyone else was asleep before joining the club with the bloke sitting next to her. She insisted that the person sharing their row of seats never woke up, but who sleeps that heavily on a plane?
It should be made illegal. There are children flying with their parents. Allowing something like this means lowering the standard of public decency. One may insists he is not breaking law and offend the other passanger and may cause argument hence causing disturbance to the air crew & passanger alike. Commonsense has to rule. Vast majority of people are descent and have an understanding of social responsibility.
Moe, London, UK
What if you're on a long-haul flight and the aircraft is over International Waters when you join the club? Surely no laws apply then - except for possibly the airline's carriage rules?
Glenn Jones, Birmingham, UK
Glen's comment about being safe from prosecution over international waters is an interesting one. If you are over international waters can you murder your partner/friends/boss? I doubt it. So laws must still apply.
Once the doors have been locked, the applicable law is that of the vessel. In BA and Virgin's case that would be English law, which punishes having sex in a public facility toilet under section 71 of the Sexual Offences Act 2004.
I joined the Mile High club while travelling to Cyprus with my boyfriend at the time. No one saw and we didn't get caught and I don't regret it for a second. It's harmless fun but I would never even have considered doing it anywhere else on the plane in view of others or while others were sleeping, that's not right. I can't see how it might offend others or be illegal whilst it's behind a closed door - if I cottoned on to it happening on a flight between two consenting adults I'd just smile.
Nothing will ever beat the raucous cheering and clapping that woke me up on a flight to Australia when the two strangers in front of me "returned to their seats" from the loos. The last I'd heard was the two of them discussing (a bit loudly, I must say) their respective failed relationships over a drink or two, as I was drifting off to sleep behind them. He was dead-chuffed, she was distraught.
I have observed a couple coming out of a public toilet separately and there is no sight more tacky in the world.
Aircraft toilet a public place? A bit of tight squeeze, especially on Lufthansa City Line, you're lucky if you can stand upright alone, never mind with a companion.
Geoffrey Ellis, Cheshire/Hamburg
As a frequent flier, I was unnerved to read that Viagra is to be sold over-the-counter under a "pilot scheme".
David Dee, Matola Mozambique
If anything should be made illegal, it should be that Viagra joke.
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