Volcanic ash

News from EUROCONTROL’s aviation safety knowledge base SKYbrary

On 15 April 2010, a large volcanic ash cloud moving south across North West Europe caused significant disruption to air traffic. During a volcanic eruption, huge quantities of material can be ejected into the atmosphere, reaching great height and remaining a threat to aviation for several months. Volcanic ash is comprised of very small hard rock particles. The ash does not show up on an aircraft’s weather radar because of the small size of the particles. These particles conduct electricity and the electrical charges within a cloud of volcanic ash can give rise to thunder and lightning. St Elmo’s Fire, created when the charged particles hit the aircraft, may be the first indication to the crew that they flying into volcanic ash clouds. Other indications are a sulphurous smell and dust within the cabin. Volcanic ash is of course very bad news for the engines…
Read the full Skybrary article here.