With more and more airlines arguing that even with Iceland's latest ash cloud descending over Europe it is still safe to fly, a flight operations manual released by Airbus has revealed just how damaging a meeting with volcanic ash can be on a modern plane.

The handbook highlighted how a collision with volcanic ash could potentially cause damage to a plane's windshields, forward cabin windows, navigation and landing light covers, wing stabilising covers, wing fin leading edges and -- perhaps most disturbingly -- engines.

Within the book, volcanic ash is described as, "highly abrasive particles that may damage aircraft components.

"They are made of sharp rock fragments that will easily erode plastic, metal and even glass pieces."

According to the Airbus manual, "Ingestion of volcanic ash by engines may cause serious deterioration of engine performance due to erosion of moving parts and/or partial or complete blocking of fuel nozzles.

"Volcanic ash contains particles, whose melting point is below engine internal temperature.

"In-flight, these particles will immediately melt if they go through an engine. Going through a turbine, the materials are rapidly cooled down, stick on the turbine vanes, and disturb the flow of high pressure combustion gases."

The manual went on to reveal that in worst case scenarios, these effects could lead to a permanent stalling of the engine.

Worse still the manual illuminated the potential risk an encounter with volcanic ash could have with a plane's electronic systems, "Volcanic ash is made of very fine particles (down to one micron) that can easily penetrate all but the most tightly sealed enclosures. It may carry high static charge.

"Ash deposits easily absorbs into water and can cause arcing, short circuits and intermittent failure of electronic components."

As a knock on affect of this the manual outlined how, "Dense ash deposit can clog bleed system filters and may lead to total bleed loss, with associated loss of cabin pressurisation."

The handbooks warnings support the findings of the Finnish Airforce, who last year tested the ash's effects on the engines of several of their Boeing F-18 Hornet Fighter jet plane's. The tests saw every engine used in the experiments damaged, sometimes irreparably.