Iceland’s Mount Eyjafjalljokull a volcano beneath Iceland’s Eyjafjallajokull glacier began erupting Wednesday for the second time in less than a month, triggering floods and shooting smoke and steam miles into the air. About 700 people from rural areas near the volcano were evacuated Thursday because of flooding.

The volcano erupted Sending out  highly abrasive, microscopic particles that make up volcanic ash pose a threat to aircraft because they can affect visibility and get sucked into airplane engines, causing them to shut down. The ash can also block pitot tubes, which supply vital instruments such as air speed indicators, or latch onto engine blades, forming a glassy substance that may cause engines to surge or stall

At first only airports in Scotland were affected and closed as precaution.  NATS the UK’s laeading Air Navigation Service Provider then announced all UK airports were to close bringing chaos to flight travel.

In 1982 a British Airways flight got into difficulty as a result of passing through a volcanic cloud.

When all four engines on the Boeing 747 being flown by Captain Eric Moody shut down at 37,000ft, he hadn’t a clue why. It wasn’t until later, when Capt Moody, his crew and the 247 passengers on board the flight, were safely back on the ground, that he discovered the cause of the narrowly averted catastrophe – volcanic ash.

Airports are being closed across the UK after dust which spewed from a volcano in Iceland, begun drifting southwards. The experience of Capt Moody, almost 30 years ago, shows the potential danger clouds of volcanic ash present to modern jet aircraft.

There had been no hint of trouble when flight BA 009 took off from Kuala Lumpur in Malaysia on the evening of 24 June, 1982. Heading for Perth, Australia, the weather forecast for the five-hour journey was good and the crew were anticipating an uneventful flight. The first sign of trouble came as the plane, which had hit cruising height, headed past Java over the south-eastern Indian Ocean.

Capt Moody, who had left the cockpit for a stroll, was summoned back to the flight deck. As he climbed the stairs of the Jumbo he noticed puffs of “smoke” billowing from the vents in the floor and detected an acrid smell. When he opened the door to the cockpit he saw the windscreen ablaze with a St Elmo’s fire – a discharge of static electricity.

But that alone wasn’t enough to cause alarm, Capt Moody says, recalling the events when he spoke to BBC’s Good Morning Scotland on Thursday.

“That’s not unusual in high wispy cloud. But it developed into something more than we’d ever seen before.”

Looking out the side windows of the cockpit, the crew noticed the front of the engines were glowing as if lit inside. Then Capt Moody’s flight engineer detailed the impact the dust was having on the aircraft itself.

“Engine failure number four… engine failure number two,” he said.

“Three’s gone… They’ve all gone.”

Within a few moments, a passenger jet powered by four Rolls Royce engines had become a glider.

Needing time to calmly consider his options, Capt Moody used autopilot to put the plane into a gentle descent, and instructed his first officer to issue a mayday call.

While the crew on the flight deck were frantically trying to figure out the cause of this freak failure, many passengers were largely unaware that anything was wrong.  But eventually, when the passenger oxygen masks dropped as the plane steepened its descent, the news had to be announced.

Eventually, after quarter of an hour without any power, the engines were brought back to life. Ash had clogged the engines, which only restarted when enough of the molten ash solidified and broke off.

“We glided from 37,000ft to 12,000ft before we got [the engines] going again,” recalls Cpt Moody.

The plane headed back to Jakarta where it landed safely, though even then one of the engines had failed again.  It was two days before investigators confirmed that volcanic ash had been responsible for the near disaster. The plane had flown into a cloud of dust spewed out by an eruption of Mount Galunggung, 110 miles south east of Jakarta.

A close examination of the plane revealed the damage a plume of these tiny particles can do to an engine – the tips of the turbine blades had been ground away. The findings were eventually incorporated into a report on the dangers of volcanic ash to aircraft.

Reflecting on the chilling events of that flight 28 years later, Capt Moody shows the sort of understatement characteristic of those in his profession.

-BBC News

The National Air Traffic System (NATS) issued the below statement.

Statement on Icelandic volcanic eruption: Thurs April 15, 20:20

The cloud of volcanic ash continues to cover much of the UK. Following a review of the latest Met Office information, NATS advises that restrictions will remain in place in UK controlled airspace until 1300 (UK time) tomorrow, Friday 16 April, at the earliest.

However, flights from Northern Ireland and the Western Isles of Scotland to and from Glasgow, Edinburgh and Prestwick may be allowed in the period from 0100 (UK time) to 1300 (UK time) tomorrow subject to individual co-ordination. North Atlantic traffic to and from Edinburgh, Glasgow, Prestwick and Belfast may also be allowed in the period.

We will review further Met Office information and at 0230 (UK time) tomorrow we will advise the arrangements that will be in place through to 1800 (UK time) tomorrow. However be aware that the situation cannot be said to be improving with any certainty as the forecast affected area appears to be closing in from east to west. We continue to work closely with airports, airlines, and the rest of Europe to understand and mitigate the implications of the volcanic eruption.

• NATS handled 2.2 million flights in 2009, covering the UK and eastern North Atlantic, that carried more than 200 million passengers safely through some of the busiest and most complex airspace in the world.
• NATS provides en route air traffic control from its centres at Swanwick, Hampshire and Prestwick, Ayrshire.
• NATS also provides air traffic control services at 15 of the nation’s major airports including Heathrow, Gatwick, Stansted, Birmingham, Manchester, Edinburgh and Glasgow, together with air traffic services at Gibraltar Airport.