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?"

Comments

The Precautionary Principle in action: test case

[Budenny]

The way to look at this might be as follows. We have an example of the precautionary principle in action, and can use it to assess the probably results of making this a guideline for setting public policy. The leading case where it is claimed that we should apply the supposed principle is Global Warming. It is argued that the precautionary principle mandates immediate drastic action to lower CO2 emission levels if there is even the slightest chance that continuing at present levels would lead to the end of human civilization on Earth.

We had a similar argument about ash: if there is even the slightest chance that flying through the ash will cause planes everywhere to fall out of the sky, we should ground them all at once.

In fact, the situation turned out to be much more nuanced and complicated. When the analysis was done, it turns out that there there was probably no need to ban all air travel, though there was a real danger, and a real need to take precautions and do proper assessment of damage. It is not safe to fly through clouds of ash. But there were not clouds of ash everywhere that was closed. In fact, we would in retrospect have done better to investigate the real situation carefully by test flights immediately. We'd then have discovered that quite a lot of flying, quite a lot of the time, would have been perfectly safe, and that there are ways of telling when its prudent to limit flights in the light of changing weather and eruptions.

The bottom line is, we incurred huge unnecessary costs, and worse, until quite late in the crisis the authorities acted as if their use of the PP made it unnecessary to investigate in detail what the real situation was.

Now if we imagine a world in which the PP is used all the time, on larger and larger issues, including Global Warming, we see that the result for public policy would be one in which policy makers neglect proper analysis and start to jump in fear at shadows. That is, cases in which there is neither real danger nor any proper analysis will increasingly dominate expenditure on measures which are done with no proper reason behind them, on a 'just in case' basis. The costs of these measures, which it is thought 'denialist' to weigh, will be huge, will in fact be so great as to prevent any proper treatment of the real danger.

This case shows that there is no substitute in public policy for proper risk assessment, and for proper analysis of the benefits and costs of proposed actions. Its a commonplace in medicine, where we have the 'number to treat' parameter - that is, how many do we have to treat to save a life, what are the side effects on those we treat? We need exactly the same thing with all public policy issues.

The difficulty with the Precautionary Principle, which you can see here, is that its invocation is used to avoid rigorous analysis of the real risks and costs of alternative actions. And it results in completely pointless and inordinately expensive measures being taken.

Think about that, the next time you see some huge windfarm, blades stationary, in a flat calm on a prolonged cold spell in the winter, when electricity demand is soaring. If there is only the smallest chance that covering the planet with windmills will save civilization, surely we ought to do it? Not really!

Re:From what I've heard, it really is that bad...

[bkpark]

I speak as someone whose flight was cancelled.

I speak as someone whose returning flight to U.S. was canceled after nearly 2 month's overseas travel. It was a definite over-reaction; if the law is that even 1 ppm of volcanic ash is enough to ground planes, then the law should be changed.

At the very least, there should be an option for desperate travelers (like myself, who was stuck in Europe for over a week after planning to be in that miserable continent for less than 3 hours, i.e. the layover at Frankfurt) to fly, after fully being informed of the risk and signing appropriate waivers.

And the test flights weren't publicity stunts: Lufthansa alone sent out at least 10 such test flights. The CEOs being on the flights? Sure. But they don't have 10 CEOs (per airline) to put on every one of the test flights anyway—not to mention presence of CEOs themselves are scientifically useless.

Re:Volcanic ash is a poor input

[Bigjeff5]

Volcanic ash in the air can be as course as 1.5", or as fine as 60 microns.

Got news for you, 1.5" grains of "ash" (we generally call stuff that big "rocks") fall out of the sky really fast - almost everything that is held suspended in the air is closer to the 60 micron range. Particles small enough to float in the air are nowhere near large enough to sandblast anything. Think smoke from a fire, the particles that are floating in the air are about that size, maybe slightly bigger. It would take a hell of a lot of flying in that stuff to see any kind of marked difference from flying in clean air. If anything happens to your windscreen at all, it will be polished by the ash, not obscured.

Also, if it's small enough to stay in the air without significant winds keeping it there (like a dust storm, for example), then more than likely it will be directed away from the skin of the aircraft due to turbulence on the skin's surface. That same nasty resistance that creates drag is also going to push small particles away from the aircraft.

You'll get more wear than clean air, but I doubt you'd notice it. Wearing through the skin of the aircraft is one thing that nobody has been concerned about, nobody is that stupid. Well, nobody who knows anything about volcanic ash, anyway.

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.

I suppose that's why flying is still considered the safest form of travel, and by a large margin, huh? Because airlines have a history of ignoring common sense and basic safety? Don't be daft man.