Many flights in the United Kingdom and northern Europe have been grounded because of the volcanic ash cloud that originates from Iceland.
Why are volcanic ashes dangerous?
Firstly, they act as sandblast on the windscreen and obscure the pilot’s visibility. The ash particles can block fuel nozzles and cover the holes that detect airspeed, resulting in unreliable speeds - that means difficulty flying the plane. Next, the ashes start to melt and vaporize inside the combustion chamber, causing further internal damage and subsequently, the engines to fail.
I am glad to say that all airlines pilots are generally well prepared for this emergency. In fact, in my airline, all the pilots were already or in the process of being checked (kind of 6-monthly test) to handle this particular emergency even well before the report of this major volcanic eruption.
Why the precautions to shutdown the airspace across Europe?
Well, volcanic ash is invisible to pilots at night and neither can they be detected on the weather radar. Because they are so light, the wind can carry them many thousand miles from the source of the volcano. So the duration of the closure of the airspace will depend on when the ash cloud dissipates or blown away to areas of less major air routes.
There were at least two major close calls in the past. In 1989, a KLM Boeing 747 lost power after passing through an ash cloud from a volcano in Alaska. Luckily, the crew was able to restart its engines during the glide from its cruising altitude.
The other near disaster happened on a British Airways Boeing 747 in 1982 when the aircraft flew through invisible volcanic ash over Indonesia. Fortunately, the pilot was able to successfully restart the engines during the descent. (See 1st You Tube video below)
1. British Airways B747 – All Engines Failed
2. Ash grounds flights in UK and Northern Europe
3. NASA satellite image of Iceland volcano ash plume over Europe
I am going to take the flight from Edmonton to London next week, I am very worry about this volcano issue, would the flight be so pumpy and unstable next week ? I am really scare to take flight, I hope you can give me some advise here.
