Volcanic ash grounds hundreds of European flights

LONDON (Reuters) - Volcanic ash from Iceland caused widespread disruption at airports in Britain and other parts of northern Europe on Monday, delaying or grounding hundreds of flights.

Britain's two biggest airports reopened after overnight closures, but passengers were warned to expect long delays and cancellations through the day.

Airports in Ireland and the Netherlands were also closed over fears that drifting ash could damage jet engines and bring down aircraft.

The same Icelandic volcano's ash last month prompted a number of European countries to close their airspaces for nearly a week and travel chaos ensued in Europe and beyond.

A spokesman for Europe's busiest airport Heathrow, in west London, said it had reopened at 2 a.m. ET.

"However, delays and cancellations are likely due to restrictions being applied," the spokesman said.

Gatwick, London's second biggest airport, will remain closed to flight arrivals until 8 a.m. ET. Nearly 150 arrivals and departures will be canceled on Monday morning, about half the scheduled total.

Britain's air traffic control body said a no-fly zone was imposed over much of Britain because the ash cloud was changing shape and drifting.

"Heathrow and Gatwick airports will be clear of the no-fly zone," it said in a statement. However, "restrictions will have to be applied due to their close proximity to the no-fly zone."

It is due to issue an update at 4 a.m. ET, a Gatwick spokesman said.

Airports in Amsterdam and Rotterdam would be closed for at least eight hours from 6 a.m. (12 a.m. ET) on Monday, Dutch state television reported, effectively halting most air traffic in and out of the Netherlands. Other, minor Dutch airports were not be affected.

Amsterdam Schiphol is Europe's third-largest cargo airport and fifth-largest passenger hub.

In a statement on its website, Dutch airline KLM said: "We are currently working on a diversion plan for all affected flights to Amsterdam."

APRIL CHAOS

More than 100,000 flights were canceled across Europe last month because of the volcanic ash forming a cloud over the continent.

Millions of people were stranded and airlines, already battered by the global economic downturn, lost $1.7 billion, the International Air Transport Association has said.

At the weekend, North Atlantic flights through Irish-controlled airspace were unaffected by the latest cloud of ash, with Shannon -- an important stopover for flights to and from the United States -- remaining open.

But information notices at Schipol airport on Monday showed some flights from the United States had been canceled.

The volcano under the Eyjafjallajokull glacier in Iceland has been erupting for weeks and the ash plume has reached heights of 25,000 feet, according to Britain's Meteorological Office.

"The ash cloud is expected to clear the UK during Tuesday as southwesterly winds become established during Monday," it said.

Volcanic ash contains tiny particles of glass and pulverized rock that can damage engines and airframes.

In 1982 a British Airways jumbo jet lost power in all its engines when it flew into an ash cloud over Indonesia, gliding toward the ground before it was able to restart its engines.

The incident prompted the aviation industry to rethink the way it prepared for ash clouds.

Railway companies laid on extra trains to cope with increased passenger levels resulting from the closure of airports.

Channel tunnel rail operator Eurostar said an extra 3,500 seats would be available for passengers.

British rail firm Virgin Trains said it would provide an extra 7,000 seats on Monday, mainly on the Birmingham to Glasgow and Edinburgh, and London to Glasgow routes.

(Additional reporting by Peter Griffiths; Editing by Matthew Jones)