Unintended consequences of regulation

Ronald Bailey looks at some interesting ideas on possible similiarities between the D.C. Metro train collision in June and the recent Airbus crashes . . . lead-free solder:

Over at DC Metblogs, contributor TONIGM speculates about a possible source for the problem - tin whiskers. As he explains:

When people first started building electric circuits, they used tin metal to solder the interconnections between the copper bits. It wasn’t long before they noticed the tin would get “furry”, growing spiky whiskers as the part was used. These spikes could grow long enough to short out the circuits, and then were so weak that they would break off right after doing so. A smart metallurgist figured out that adding a small amount of lead to the tin alloy stopped this behavior.

[. . .]

So yesterday, I dropped a note to one of my expert friends, who agreed with me that the circuitry in the Metro replacement part, more likely than not, contained lead-free solder. And then, he pointed out the likelihood that the latest Airbus crashes had lead-free solder components in their flight controls.

Could the Metro crash have been causeed by yet another unintended consequence of zealous regulation? We'll see what the investigators determine.

That's a disturbing thought, as we've grown more and more dependent on (relatively speaking) flawless performance of our electronic gadgets . . . and the worst problems to try and diagnose are intermittant ones — where a temporary glitch only shows up now and again, not in a predictable pattern.