so just how close did they get?
looks like the RYR flight might not have done what was thought. This from the BBC live news feed on their website.
1229: Government sources tell the BBC they are questioning assertions from Ryanair boss Michael O'Leary that one of its planes went through the ash cloud.
1230: A source told the BBC the plane did not go through the "red zone", where ash is at its most dense, and did not have measuring equipment on board. Radar tracked the plane which was travelling at 41,000ft.
1237:
More now on Ryanair's claim that its test flight detected no ash cloud over Scotland. Aviation regulator CAA confirms that at "no time did a Ryanair flight enter the notified area of high contamination ash over Scotland this morning".