UK CAA removes buffer zone around ash cloud

Effective midnight last night, the UK Civil Aviation Authority and Irish Aviation Authority have removed the arbitrary 60nm safety buffer zone around airspace where the volcanic ash cloud is predicted to be.
The decision was informed by recent experience with aircraft operating in the vicinity of ash over Europe.
The CAA says it expects other European national aviation authorities (NAA) to follow suit.
A series of actions have been taken or planned by NAAs since ash from the Icelandic Eyjafjallajokull volcano began to contaminate European airspace on 14 April, the first of which - on 20 April - was to declare that aircraft would be allowed to fly in ash that was below a given intensity. The latest measure effectively increases the amount of usable airspace for airlines.
The UK CAA says that it has now exhausted its short-term options for improving airlines' ability to operate safely in the vicinity of ash. It adds, however, that since volcanic ash could become a permanent risk around Europe's skies for many years to come, the industry is going, in the medium term, to have to address other options scientifically.
These include: reassessment of the ash intensity limits that the engine manufacturers at present deem acceptable, to see if they can safely be raised; and reassessment by the airlines, on a cost-benefit basis, of whether they are prepared to accept the costs associated with a quantifiable amount of cumulative degradation to their aircraft engine and airframe efficiency.
The latter would be calculated against the benefit of fewer flight cancellations, and on condition that the damage does not affect safety.
Many European airlines are protesting that the US Federal Aviation Administration operates a more flexible ash risk regime which, if it were adopted in Europe, could result in fewer cancelled flights. The CAA, however, reveals that the FAA has advised Europe against adopting its specialist practises in an "off-the-shelf" manner.
An example of FAA flexibility is that it allows Alaska Airlines - which operates in airspace with a higher-than-average ash risk because there are several local volcanoes - more autonomy in its decisions about operating when ash is known to be in the atmosphere. But this autonomy has been conferred because Alaska trains its flight crews regularly in ash encounter drills. Alaska itself says that it "does not even taxi" when volcanic ash is known to be present in the atmosphere, preferring total avoidance.
The Alaskan region, which has its own Volcanic Ash Advisory Centre, uses the same terms of reference for ash detection and advice as the London and Toulouse VAACs, which cover the North Atlantic including Iceland, Ireland, the UK and the whole of continental Europe