Thursday, April 15, 2010
Hundreds of thousands of air travelers had their travel plans disrupted in Europe by volcanic ash from the Eyjafjallajökull eruption.
Tens of thousands of air travelers were stranded when all flights into and out of the United Kingdom were grounded, as it became one of the first nations to be affected. The grounding was even more extensive than that following the September 11 attacks of 2001 when only trans-Atlantic flights were canceled.
Eurocontrol released a statement saying “…most air traffic in the United Kingdom, Ireland, Denmark, Norway and Sweden is suspended.”
The grounding is because the volcanic ash drawn into the jet stream is of a particle size which allows it to remain aloft in the atmosphere. Ingestion of this foreign matter, because of its distribution, would lead to flame outs in all aircraft engines. The composition of the ash also means that it would first melt into glass if it were to enter the engine of an aircraft before solidifying again as it cooled. This could lead to damage to the compressors and fan blades, which would make it impossible to restart the engines, even if the aircraft were to exit the cloud.
The current contingency is informed by the experience of British Airways Flight 9, which on June 24, 1982 suffered just such complete engine flame outs when it flew through the plume of Mount Galunggung in Indonesia. In that case, the flight crew after many efforts was able to restart the engines, though one failed shortly after, and the aircraft landed without casualties.
The UK National Air Traffic Services (NATS) has stated that “restrictions will remain in place in UK controlled airspace until 1300 (UK time) tomorrow, Friday 16 April, at the earliest,” and that “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.” The NATS statement concluded “…the situation cannot be said to be improving”.
In addition to Northern Europe, the ash is drifting south; Berlin and Hamburg airports in Germany are closed, and airports in the Netherlands, Belgium and Northern France are described as now being closed or closing. Some flights from Spain and Portugal, together with upwards of 4,000 flights across Northern Europe, have been affected, and the knock-on effect of aircraft and crews out of position could disrupt air travel worldwide for up to 72 hours.