Ash cloud: satellite view.

Business travellers face severe disruption as all flights in and out of the UK, Ireland and the Nordic and Benelux countries have been suspended while a high-level cloud of ash from the volcanic eruption in Iceland moves south.

Up to 4,000 flights are being cancelled with no flights allowed in UK airspace until at least 0700 BST on Friday, the UK's air traffic control service National Air Traffic Services (NATS) said.

Engine failure

The airspace restriction – which is the worst in living memory – has been imposed amid fears of aircraft engine damage.

In 1982 a British Airways jumbo jet had all four of its engines shut down as it flew through a plume of volcanic ash, while on 15 December 1989, KLM Flight 867 – a B747-400 from Amsterdam to Anchorage in Alaska – flew into the plume of the erupting Mount Redoubt, again causing all four engines to fail.

The ash cloud from the Icelandic eruption is shown in this satellite photograph (left), courtesy of NEODAAS/University of Dundee.

A senior lecturer in volcanology at the University of Leicester, Dr Mike Branney told the BBC: ‘Volcanic ash is not good to plane engines. Firstly, it is highly abrasive and can scour and damage moving parts. Secondly, if it enters a jet engine the intense heat of the engine can fuse it to the interior of the engine with a caking of hot glass, which ultimately can cause the engine to cut out completely.’

Resumed service uncertain

NATS was not confident the restrictions would be lifted at 7am tomorrow, saying it was ‘very unlikely that the situation over England will improve in the foreseeable future’. It is set to make an announcement at 8pm regarding arrangements that will be in place through to 13:00 BST on Friday

Airport operator BAA has advised passengers to contact their airline prior to travelling.

Meanwhile, Eurostar and other train and ferry services have seen a massive increase in bookings, as passengers seek alternative means of getting to their destinations.

Second eruption in a month

The eruption under a glacier in the Eyjafjallajoekull area of Iceland is the second in the country in less than a month.

Professor Bill McGuire, from the Aon Benfield UCL Hazard Research Centre, said it was not ‘particularly unusual’ for ash from Icelandic eruptions to reach the UK.

He told the BBC: ‘Such a large eruption... would have the potential to severely affect air travel at high northern latitudes for six months or more. In relation to the current eruption, it is worth noting that the last eruption of Eyjafjallajoekull lasted more than 12 months.’

No health risk

However, the ash cloud does not pose a significant risk to public health because of its high altitude, the Health Protection Agency has said.

And every cloud has a silver – or crimson! – lining, with the large amount of ash in the atmosphere likely to lead to particularly stunning red sunsets in some areas.

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