Why Is Volcanic Ash So Dangerous for Planes?

A volcano erupting hundreds of miles away in Iceland is causing havoc for air travellers in the UK -- but why is volcanic ash so dangerous for pilots?

Pilots are advised never to fly though an ash cloud because of the extreme problems it can cause an aircraft. Ingesting ash dust can cause partial or total engine power loss. Simultaneous power loss in all engines has also occured.

The ash will also damage aircraft ventilation, hydraulic, electronic and air data systems along with the plane's paint, windscreens and powerplants.

Former British Airways pilot Eric Moody has first-hand experience of flying through an ash cloud. In June 1982 he was piloting a Jumbo 747 from Kuala Lumpur to Perth, Australia when he hit an ash cloud just off Java.

"It was very frightening, all the engines stopped for 14 to 15 minutes and we didn't know what was happening," he told Sky News.

"It was dark and the effect was of St. Elmo's fire around the aircraft. We were looking for the cloud that had caused it but didn't know it was a volcanic ash cloud.

"We glided the aircraft about 80 nautical miles and went down 37,000 feet to about 12,000 feet. That was when we must have come out of the bottom of the ash cloud. It was a dark old night."

As a result of Mr Moody's flight experience research into the effects of volcanic ash clouds on aircraft increased and Volcanic Ash Advisory Centers were established around the world.

"Flying into volcanic ash is as deadly as flying with ice on your aircraft," said Mr Moody. "And everyone knows how dangerous that is."

This disruption in the UK is being caused after a massive cloud of ash from a volcano in Iceland drifted into UK airspace.

Several UK airports are closed and hundreds of flights have been cancelled.

In Iceland, hundreds of people have fled rising floodwaters since the volcano under the Eyjafjallajokull (ay-yah-FYAH'-plah-yer-kuh-duhl) glacier erupted Wednesday for the second time in less than a month. As water gushed down the mountainside, rivers rose up to 10 feet by Wednesday night.