When I tried to check in for my flight to Montreal via New York JFK, I couldn't - and couldn't understand why.

The "Manage my booking" page said that American Airlines had all the information it needed for me to check in: I could, it said, check in from 24 hours to 60 minutes in advance. But I couldn't - I was trying off and on during the afternoon, within those times, and got the "Can't check in - go to the airport and see an agent". I still don't know why this happened - it may be the topic of another blog.

On the morning of my flight, I heard on the 7:00 news that a cloud of volcanic ash drifting in from Iceland had caused the closure of Aberdeen, Edinburgh and Glasgow airports.

I got to Heathrow at around 9:00, and was told that I couldn't yet check in - they were checking people in for earlier flights but not mine, leaving at 11:55. "Come back in an hour", they said.

BAA's Flying Messenger service kicked in to tell me that the flight was on time: American Airlines staff were then saying that they thought that the entire airport was likely to close shortly.

Ironically, one of the flights which was departing was a Boston flight. When I had booked originally, I had been offered this flight but rejected it - despite it being fifty pounds cheaper - because it involved changing at both Boston and LaGuardia.

The flight departure screens were still just giving information about the check-in areas: AA people said that the screens were unlikely ever to show the flight as cancelled.

The only source of information was the two people staffing the entrance to the check-in area - who were really doing a good job. The self-service machines had pieces of paper saying "Closed" taped over the screens: there was no other information apart from the two over-worked staff. No whiteboard, no tv screens, nothing. These two ladies were dependent on getting information from colleagues, which seemed a bit haphazard because they were so busy dealing with questions from passengers.

The television screens in the terminal, normally displaying news, were showing shots of the volcano and a streaming message, "All flights into UK airspace after noon cancelled".

At 10:30, Flying Messanger said, "Check with airline".

There are few generally available seats landside in Terminal 3, and none in sight of American Airlines' check-in area.

I returned to the office: as I was going past the flight information screens at Heathrow Express's Paddington ticket office it showed many flights cancelled - well done!

I phoned American Airlines and got through to a real person with commendable speed. Equally commendably, they had already re-booked me - on a flight at 7:55 next day via Chicago, unfortunately arriving 5 hours late for my meeting!

Also unfortunately, it meant being at Heathrow at 5:30 and all airport hotels were full. This meant staying a 20 minute bus ride from Paddington and catching the first Heathrow Express, at 5:10. Another downside was the lack of good seats on the plane: rather than staying with the centre of 5 I'd been allocated, I chose an aisle right at the back. Normally I go for a window: I'm a compulsive window viewer!

By lunch-time, London Underground had some very good posters and notices about the cancellation of all flights at stations (well done!): at Paddington, Network Rail had a rather more verbose one.

So Heathrow Express and London Underground both scored highly for disruption information, and American Airlines scored for good staff on the ground and for re-booking me.

And, at 16:00, I still couldn't check in for my flight at 7:55 next morning (although there was an aisle seat rather further forward than the one I'd booked!).