Posted on 04/16/2010 10:04:01 PM PDT by ErnstStavroBlofeld
Finnish fighter jets which flew through the volcanic dust covering much of Europe suffered damage and the air force warned Friday the cloud could have a significant impact on planes.
The air force F-18 Hornet jets were on training flights in northern Finland on Thursday morning, when airspace was still open, and the engines were later found to contain fine, volcanic ash dust.
"Based on the pictures, it was discovered that even short flights in ash dust may cause significant damage to an airplane's engine," the Finnish Defence Forces said in a statement.
Images taken inside one Hornet engine with a fibroscope camera indicated that the heat of the engine — around 1,000 degrees Celcius — had melted the ash inside the engine, blocking ventilation channels.
"Blockages of ventilation channels caused by melting ash lead engine components to overheat and material to weaken," it said, adding this could fracture rotating engine parts.
In the worst case, the weakening of component materials could cause "parts to detach and the engine to be destroyed," it said.
The Hornets exposed to the dust from the eruption of a volcano in Iceland would be checked thoroughly, with "at least some" of the engines detached and sent for further studies and repair.
The air force would keep a Hawk combat aircraft equipped with a tank to take atmospheric samples on standby to assist civilian authorities as necessary, it said, adding that operative military flights would continue normally.
Samples taken by the plane, which collects particle samples in a filter in the tank, could be used to analyze how much ash dust was in the air.
A huge cloud of volcanic ash from Iceland has spread over large part of Europe,
(Excerpt) Read more at vancouversun.com ...
Thanks for expanding coverage Pangaea link facinating and offers background info into volcanic dust
- St. Helens erruption plume contained larger particles. The stuff exhausted from iceland is much finer and remains longer in the air.
- Air traffic in 1980 was nothing compared to airtraffic today.
The F-4 taxied out to line up on runway 27 and the crew ran through their checklist. They were patched in to the PA system so we could hear.
The pilot announced he had set his brakes and would run each engine up to full power...one at a time. "If I go to full power on both engines, we'll just skid down the runway."
He then lit burners, released brakes and accelerated until he rotated right in front of the crowd. The ground was shaking. He pulled vertical and was gone. All I could think was "Wow!"
Any jet engine mechanic worth his salt could have told those dumbasses that this would have happened.
It’s happened before with commercial airlines as well.
The problem is the cooling channels in the turbine blades in the High Pressure Turbine just behind the combustion chamber. If those get blocked, the blades will overheat and eventually fail, causing any number of catastrophic failures, the most common would be the blades coming apart and destroying the engine.
Some engines also have cooling holes in the combustion chamber liners. If those get blocked, you may have a burn through, into the boundary air layer.
Pilot recounts day of heroism on Mount St. Helens
"Commercial air traffic throughout the area ground to a halt because of the reduced visibility and potential hazard of flying through ash clouds rising 80,000 feet into the sky."
Saw a flight of F-4 flyin in Egypt a few years back. Heard them and my heart skipped a beat, then saw them. Brought back a lot of good memories. Good to see the old girl still flying and doing the job.
Boundary air control makes that moaning sound. Almost wonder if McDonnell could have called it Banshee II.
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