Frequently Asked Questions

Answers to the most frequently asked questions regarding the current volcanic ash situation

Who does what when there is ash in the UK’s airspace?

The Met Office
Met Office forecasters monitor volcanic eruptions as part of the Met Office’s role in the global network of nine Volcanic Ash Advisory Centres (VAAC). The Met Office provides forecasts every six hours giving an 18-hour prediction of where the volcanic ash cloud is and where the different levels of volcano ash lie.

The Met Office forecast is then used by the CAA to produce an aeronautical Notice to Airmen (or NOTAM) based on this information every six hours to inform industry of the location of medium and high density ash.

NATS provides air traffic control services to aircraft flying in UK airspace, and over the eastern part of the North Atlantic. It uses the NOTAMs issued by the CAA to brief airline operators and airports on the areas that will be affected by the ash cloud.


Can draw up safety cases to show how they can safely operate in ash. They invovle input from engine and aircraft manufacturers and need to be accepted by the CAA. Some UK airlines have safety cases to fly in medium density ash.

Why is ash still disrupting flights?
Last April the CAA led international manufacturers and regulators in developing new standards to allow flights to continue.

Since then the CAA and the aviation industry have been working to ensure high levels of safety but reduce disruption from ash. This work has included putting in place a new operating regime which means there will be no airspace closures. Instead areas of high and medium density ash, as indicated by the Met Office, will be notified to airlines. If an airline has a safety case to operate in those notified areas then it may choose to do so.

What is the risk posed by ash?
Volcanic ash is very abrasive. It wears the blades and vanes in aircraft engines, impacting the aerodynamics of the compressor and potentially leading to loss of thrust and engine stall. One of the most serious incidents affected a BA Boeing 747-200 in 1982, in Indonesia, when all four engines failed after encountering volcanic ash.

How do I find out if my flight will be affected? 
Any volcanic ash is constantly monitored, with information fed through to airlines to alert them to potential restrictions. If you think your flight might be affected, you should contact your airline for an update before leaving for the airport.

Where can I find some consumer advice?
Advice for passengers affected by a cancellation or delay to their flight as a result of the ash disruption.

How will this affect air travel in future?
As the UK has some of the most congested skies in the world, no fly zones may continue to disrupt UK flights until the volcano stops emitting ash or the aviation industry comes up with technical solutions to allow aircraft engines to fly safely through denser levels of volcanic ash.

The safety of passengers is our number one priority. The CAA lead international manufacturers and regulators in developing new standards to allow flights to continue whilst flying close to, or through, the ash cloud, but when the ash level exceeds that agreed as safe by the industry we have to restrict flights accordingly.

Throughout this process, the public is at the heart of all our work and our goal will be to allow as much flying as safely possible, working with all stakeholders to minimise disruption to the travelling public while keeping them safe at all times.

If you think your flight might be affected, you should contact your airline for an update before leaving for the airport.

Why did no flights happen in UK airspace for 6 days in April 2010?
Safety always comes first in aviation and the UK has one of the world’s best safety records. This relies on guidelines which ensure that airlines and pilots operate consistently and safely. In the case of aircraft encountering volcanic ash the international guidance, drafted by those who have had to deal with it in the past and had multiple engine failures, was to avoid - regardless of the level of ash density.

Previously this guidance was acceptable, as flights had been able to reroute around the affected areas because the airspace was uncongested. However when the ash cloud settled over the UK, there simply wasn’t room to go around it. In this case, the only way to avoid ash contamination was to stop flying, until experts could agree on a safe low level density of ash.

What will happen if the eruptions continues or another volcano erupts?
We can’t stop volcanic activity, but we are continuing to work with the aviation industry to develop further technical solutions that will increase flying when we are sure it is safe to do so and are endeavouring to ensure interruption is kept to a minimum.