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Was Flight Ban Over Ash an Overreaction?
HaymarketRiot writes "Richard Branson has claimed that the flight ban, due to the eruption of the volcano Eyjafjallajokull, was an overreaction on the part of the authorities. Britain's government has even called for the airlines to be compensated. This does look like a perfect excuse for already greedy airlines to try and get more money ... any experts care to comment on the effect of volcanic ash on planes?"
Basically, the jet's internals are hot enough to melt rock back into glass... So after a couple of passes through ash clouds, you have a thin layer of glass covering all the internal turbine blades. Which completely destroys the engine, and is extremely hard to repair without completely replacing the blades.
So, basically, what I've been told is that, yes, flying a jet through a volcanic ash cloud is a good recipe for completely destroying the engines, such that they need to be rebuilt, within two or three passes through the ash. It sounds plausible, and I've not yet heard anyone who actually does aircraft maintenance or anything like that suggest that it's harmless.
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If one had flown and crashed, everyone would have blamed the governments involved for not stopping all the traffic. While I am no fan of the government, this is one where they could not win.
Grimjack
In the wild there are no dumb lions tigers or bears. Only humanity subsidizes the continued existence of the stupid.
Don't know if you put any stock in what an aircraft manufacturer might say on the subject, but...
http://www.boeing.com/commercial/aeromagazine/aero_09/volcanic_story.html
Summary: If you find yourself flying into an ash cloud, turn around immediately.
So, yeah, maybe Branson wants a check, but flying into ash clouds is a very bad idea. And they don't show up on weather radar.
Why yes, I AM a rocket scientist!
http://www.popsci.com/science/article/2010-04/why-cant-planes-fly-through-volcanic-ash-because-nasa-tried-once It basically starts to eat the plane's internals. So, while it may or may not experience problems immediately, it almost certainly will in the longer run, grounding those planes while they have parts replaced, and costing a fortune in new parts, because most of the shown damage in the pictures is not safely fixable.
Finland's air force flew into the ash cloud, and released some photos of the damage. It ain't pretty.
My vote's on cash grab.
I was in Fairbanks at the time, and many people I know where stranded, trying to get home for Christmas vacation.
That's "were," you fucking moron.
Jesus, I hate people who can't spell.
Microsoft is to software what Budweiser is to beer.
Hey moderators--look a little more closely and you'll notice that the so-called flamer and the person he flamed were the same people!
This ain't rocket surgery.
I ain't engine expert nor volcanologist nor geologist, but I'd rather think more than twice before pouring sand into my car's engine.
Suffice to say that if my car engine dies, only the engine conks, the rest of my car don't break up in pieces.
But if an airplane's engines die, it'll crash, and everyone inside the plane gonna die with it.
That old British hippie is getting way too greedy.
Muchas Gracias, Señor Edward Snowden !
The engine isn't the only important part of a jet aircraft. Apparently flying a jet aircraft through what's effectively 200 miles of sandblasting has other deleterious effects such as sandblasting the windshield, abrading the skin of the wing and other forward parts and trailing parts including the tail, obstructing the pitot tubes that gauge airspeed. Some of these effects are immediate and inconvenient (landing an aircraft when the windscreen is frosted glass can be challenging), and some are not immediately apparent but can cause aircraft failure several months after the ash is gone. Trailing edge surfaces can also be affected in subsonic aircraft, though these can be less important because critical control lines can not be routed aft of trailing edge surfaces. The mobility of ailerons and flaps can be affected by grit. This grit can cause failures in flight because the maintenance schedules for aircraft do not account for flying through powdered glass.
Let's review: Glass is harder than steel. Volcanic ash is glass. Volcanic ash in the air can be as course as 1.5", or as fine as 60 microns. The skin of aircraft are predominately aluminum. Aluminum is not as hard as steel. These ash particles can abrade aluminum. If you fly though enough abrasive, the skin of your aircraft will wear through.
The way airlines work some of these aircraft might be rotated to routes far from northern Europe, placing almost anyone at risk. Did that commuter plane from San Francisco to San Diego accumulate ash damage over the North Atlantic? You don't know.
It's better safe than sorry I think. We have a long history of airlines ignoring common sense and basic safety to put butts in the seats. They need regulation to keep them from getting stupid.
It's not like volcanos were just recently discovered. They predate airlines by a good bit, and Iceland volcanos go off on a regular basis. I say it's part of the normal order of the day for these airlines. If they're not insured against this risk then it's their own cost because they're self-insured. I'll bet some of them are getting compensation from their insurance and want to be compensated twice to improve their bottom line. Getting paid twice to not carry passengers is almost three times as profitable as getting passengers to grandma's house - especially if Grandma's house is in Finland, since they save some accellerated depreciation on a very expensive aircraft.
Help stamp out iliturcy.
The cooling system used in gas turbines (jet engines) is very sophisticated and necessary to keep the superalloy blades from creeping too fast. The system consists of bypass air channeled through the blades and exhausted through tiny perforations, creating a layer of cooler air between the blade and the hot flow from the combustor. Furthermore there are two ceramic layers on the outside of the blade. One to prevent oxidation. One to slow heat transfer (insulate). As has been mentioned in other articles, the cooling pores could get clogged by the ash. I also suspect the coating might fail if impacted by ash. If the coating fails or otherwise reacts with the ash, then you can definitely have a problem.
If the blades get just a few tens of degrees hotter, they will surely fail. There's not a lot of margin for error with jet engines. Through good design and manufacturing control, we've managed to make gas turbines extremely reliable, but ash is not a design condition at all. It's abrasive, might react with the coating, and might accumulate on the blades, changing both their mass and aerodynamics.
"There are some people that if they don't know, you can't tell them." ~ Louis Armstrong