An unprecedented no-fly zone imposed across Europe following a huge volcanic eruption in Iceland is set to remain in force into the weekend, causing travel chaos for over a million air passengers.
Airspace stretching from Ireland to Finland, including airports in London, Paris, Amsterdam and Brussels, was closed today following the violent eruption of the Eyjafjallajokull volcano in south-east Iceland which sent a plume of ash across some of the world's busiest flight paths.
All UK airspace was closed from noon except for "agreed emergencies". It is likely to stay shut tomorrow, with the force of the eruption showing no sign of abating.
Last night north-westerly winds continued to blow the eight mile high plume across the continent, raising fears that airlines could be grounded for days. One volcanologist said the ash could present intermittent problems to air traffic for six months if the eruption continued. The last time the volcano erupted in 1821, it spewed ash for two years.
The pan-European shutdown affected an estimated 4,000 flights and is the most dramatic step of its kind in living memory. It caused the most international travel chaos since the 11 September attacks on America in 2001.
Airports across France closed tonight following the lead of safety authorities in Ireland, Norway, Sweden, the Netherlands, Belgium, Finland and Denmark. Planes travelling from America to Europe had to turn back over the Atlantic and a jet carrying British forces back from Afghanistan was grounded in Cyprus. The plume is projected to spread east and south over Germany, Poland, the Czech Republic and the Baltic states, as well as parts of Russia.
"We certainly do not think we have over-reacted," a spokesman for the National Air Traffic Service said, prior to extending the total shut down of all UK airports until at least 1pm today. "Safety is our main priority and volcanic ash is a serious threat to aircraft."
In 1982, a British Airways jumbo jet became a giant glider when all four of its engines failed after flying through a volcanic plume over Indonesia. After a terrifying descent, the crew managed to get the engines started, before landing the plane safely in Jakarta.
The Met Office predicted planes will be grounded all day on Friday, while John Swinney, the cabinet secretary in the devolved Scottish government, said the ban on flights is likely to remain in place for "some days". Lord Adonis, the transport secretary, will tomorrow morning meet senior transport officials to consider contingency plans if the current weather situation continues.
The impact of the volcano, which began erupting in the early hours of Wednesday morning, eclipsed the build-up to the leaders' debate in Manchester . Gordon Brown apologised for any disruption caused by the eruption but said "safety is the first and predominate consideration". David Cameron broke off electioneering at a Halifax primary school to say it was "a very worrying and difficult situation".
The ash cloud, almost invisible to the eye, began to spread across Europe on in the early hours of Wednesday before stretching east to northern Norway, Sweden and Finland and south across Scotland and the UK, engulfing Britain totally by Thursday afternoon.
The runways and aprons at Heathrow, normally the world's busiest airport, were becalmed. Manchester airport was almost empty with 75,000 passengers unable to travel.
The eruption of the volcano which had been dormant for 187 years caused devastation in Iceland and civil protection teams had to evacuate around 700 residents when torrents of melt water flowed off the glacier through fields and farms. Day turned to night east of the eruption as thick grey ash fell, leading to fears among farmers for their grazing farm animals.
Geophysicists in Iceland said that the production of ash from Eyjafjallajokull is likely to continue at a comparable level for some days or even weeks.
"Where it disrupts travel depends on the weather," said Einar Kjartansson, a geophysicist at the Icelandic Meteorological Office. "It depends how the wind carries the ash."
John Strickland, director of air transport consultancy JLS Consulting, said the effects on long haul travel could be particularly severe because of Iceland's position on heavily used routes.
Ironically, Reykjavik airport was one of the few European airports to remain open, because the wind direction carried the plume away from the country's capital.