Volcanic ash when entering an aircraft engine melts and adhesives, causing aircraft to stop working.

The volcanic eruption in Iceland in 2010 has paralyzed aviation operations in Europe, a series of flights canceled. Volcanic dust can damage even the most modern aircraft. Here’s what happens when a plane passes through a crater, according to Rambler.
Most volcanoes are high altitude, lava eruptions can reach several tens of meters high. Volcanic ash can extend for many kilometers from the crater. These are small rock particles from the volcanic bed, scattered in the air as hot dust. The plane was not only in danger when it flew over an active crater, but also within the impact of the eruption. Meteorological agencies must closely monitor the data on wind direction carrying volcanic ash, then pass the information on to air traffic control stations.

In fact, it is difficult for a pilot to distinguish an ordinary cloud from a volcanic dust cloud visually. Volcanic ash is made up of microscopic dust particles, so it can be eroded, destroying the shells of planes that travel hundreds of kilometers per hour. Another big part of the plane is the windshield – easily obscured or broken under the impact of volcanic ash. While designers are not aware of the effects of volcanic ash, there have been instances where it caused aircraft engine malfunction, crashes and re-operation after minutes.
Volcanic ash, which has a high temperature, once flew into the engine, they continue to heat up and melt, forming a binder. This unit cools quickly, which can interfere and damage the engine, causing the aircraft to shut down the power supply.