Several planes had to deviate from their flight paths because of airspace southeast of Vatnajökull was declared as dangerous to flight, after the eruption under the Dyngjujökull glacier on Saturday. The declaration was revoked yesterday (Sunday) at noon.
The world remembers the Eyjafjallajökull eruption in 2010 vividly due to the massive disruption in flight traffic that it caused. Sky News claims that 100 thousand flights were cancelled. Since then there have been changes to flight regulations meaning that a similar eruption today is very unlikely to cause such chaos as four years ago. Despite that, flight authorities around the world are observing the situation.
Friðþór Eydal, spokesman for ISAVIA, told us yesterday that the total numbers of planes that were diverted was not known. That information would probably be known today. He believes that it wasn't a lot of flights that had to make major changes to their flight paths. "They're really not changing course, they just plot new courses that go past this area," states Friðþór. Only the first planes would have been really affected.

Bryndís Hagan Torfadóttir, executive manager at Scandinavian Airlanes in Iceland, says that her airline suffered no disruptions due to the eruption. "We weren't affected at all, but I make all announcements that are required," she says, and adds that now it's just a waiting game.
There are examples of airlines that made drastic changes to their flight schedules. Yesterday a group of Icelanders couldn't return from Germany because Air Berlin cancelled the flight due to fear of an eruption. ITV News also reports that a Virgin Atlantic airline had altered its flight path after the announcement.