I wasn't going to say anything about the volcanic activity in Iceland shutting down aviation across northern Europe, because I didn't think I'd have anything to add to the news coverage. But then CTV had a piece on it, including an interview with a former airline pilot in which they asked him why volcanic ash was such a threat to airplanes. His answer was that it forms very large clouds that don't show up on radar. That's true, but he never got to the nitty gritty of why, the literal nitty gritty, or at least gritty. Volcanic ash does not vanish to powdery nothing on your fingertips like wood ash: it consists of very hard, sharp particles of well-tempered glass. It flames out jet engines as its volume disrupts the airflow, damages the first stage from the inside by etching and abrading the perfectly machined moving parts, and then the glass can melt again inside the combustion stage of the engine and then re-congeal. Where it doesn't melt, it can mix with atmospheric moisture into a concrete-like slurry. The ash cloud also opacifies windscreens and inundates all moving parts, effectively sandblasting them.
Then the reporter set him up perfectly by asking, "Are you saying at an enormous 747 with four big engines could fly into ash and have all four engines snuff out?" By naming that specific type I suspect that the reporter had done some research and wanted the reveal of this flight or this one to be made by an actual airline pilot.
But instead of saying, "It has happened," the pilot said "it would never happen in practice," and went on to describe the satellite imagery and communications that steer aircraft free of ash clouds. I'm sure he knew about the BA flight, and was acting on the side of not panicking people and giving modern information. Technically the ash only shut down three engines on flight 9, as one of the engines had already been shut down as a precaution. That was in what saved them, because the engine that had not been running during the ash encounter was able to restart.
Oh and here's a brilliant piece of ignorance from a commenter on a CNN article. (Sorry I don't have the link, someone forwarded the text to me).
The ash cloud has stopped fights because of the danger of it stopping the aircraft engines? Another blatant lie. How were those aerial photos and videos taken? Those aircraft were far closer to the ash plume than commercial craft would fly. Why didn't their engines stop?
Perhaps the airlines sold this little falsehood because the real problem is that the ash would cause extra wear in some engines and they don;t want the expense of more maintenance. As always, the news media eagerly repeats any "official" story without thinking, "Can this be true?" Follow along now sheeple, nothing to see here. You there! Stop that thinking right now!
That person probably thinks airplanes fly just fine underwater, because he's seen lots of aerial shots of oceans and lakes. Just to be clear, that's from a member of the public in an online comments section, not a paid member of the media. But hey, at least he's not believing everything he's told.
Here's a geekmade tool showing the skies over Britain clearing of aircraft after the warning came out, the largest airspace closure since September 2001. There's an upside, though, according to this infographic on CO2 emissions.
I've never had a volcanic ash encounter, nor had to cancel a flight for ash. I have seen volcanoes and wow. The Earth itself can wreak havoc. Maybe there will be fish to eat in the future after all. Fish that breathe fire!