People living outside of the UK may be bemused at - or not even heard of - the political shenanigans currently taking place over the future of the capital's airports.
London's flagship airport, Heathrow, is close to capacity and many believe the only solution to its woes (and those of the wider region) is to build a third runway.
The proposal has been rattling around for years, with political parties (depending on where they are in the election cycle) coming out tentatively in favour or solidly against the move, green campaigners and locals fiercely opposing an extension and the industry lobbying hard for a definitive answer to South East England's air transport woes.
London mayor Boris Johnson, a colourful character at the best of times, is against expanding Heathrow (his core Tory voting support surrounds the airport, coincidentally) and has proposed creating an enormous "hub" facility to the east of the capital in the Thames Estuary, nicknamed Boris Island.
The factoid often trotted out by many is the revelation that in the time politicians, commissions and campaigners have bickered over what to do with Heathrow, China has gone ahead and built a gazillion new airports. Or something.
Wading in to the row this week, with remarkable timing given the attention on the situation post-London 2012 Olympics, is Gensler, a global design firm which has created all manner of facilities and buildings over the years, including airports.
It's proposal is simple - build "London Britannia Airport" miles away from the capital (still close to the Boris Island facility), but rather than disrupt existing land areas it wants to build the airport on, err, floats.
The airport would have four, five-kilometre in length, floating runways, each of which would be tethered to the seabed and the departure area in the centre of the facility.
Marine tunnels would connect passengers via train to Central London, European high speed rail networks (Eurostar) and other locations in the region. Genster says:

"The design’s inherent flexibility creates a platform whereby runways can be floated in as required and taken away for maintenance in the future. The concept allows for future expansion to accommodate six runways when required."
The designers claim the environmental impact would be less than existing proposals as there would no need for land reclamation, night flights could be operated miles away from residential homes, and power would come via wind turbines located adjacent to the runways.
The reported cost is anything up to £60 billion.
There is also the small matter of the SS Richard Montgomery, an American cargo ship from the Second World War which sank in the Thames Estuary in 1944 with 1,400 tonnes of high unexploded ordnance on-board.
It has never been moved for fear of triggering a massive and potentially deadly fireball and dangerous waves in the area. Although mayor Johnson claims the wreck should not impede the construction of any airport in the area, many - including government agencies - are nervous about tampering with it.
But presuming (for a second) that London Britannia Airport went ahead, what would happen to dear old London Heathrow?
Rather than let it slowly collapse into the ground and turn into a sombre graveyard for aviation geeks, Genster wants to transform the area into an "Eco City" known as Heathrow Gardens, with homes for 300,000 people and business facilities employing another 200,000.