It seems volcanic ashes is not something to be taken lightly... All air movement over Northern Europe is essentially stopped.

Some effects of volcanic ash on air planes (from recent news articles).

- Sealing off vents and openings that are supposed to be open. Like pivot tubes (air speed gauge). Pilots don't like that, for some reason.

- Sandblasting anything that's on the outside: Fuselage, engines, windows, instruments...

- Causing havoc inside the engines. Among other things, it melts (it's partly very fine powdered glass particles) and sticks to parts that are not supposed to be covered in glass.

- Creating unpleasant atmosphere inside the air craft.

That you don't see any from the ground doesn't mean there aren't any particles to create problems.

I was halfway supposed to be flying today, but was told I could skip that meeting. Stroke of luck, I guess... Alternative transport to get home would be at least 8 hours by train or bus, and tickets to those are not exactly abundant at the moment.