Smoking cigarettes in airplanes made the airplanes safer?

By “safer” I mean in regards to the structural integrity of the airplane, not as in reducing cancer risk of the passengers or something like that.

Was at my dentist today discussing a tooth with some potential small cracks, and he got to talking about smoking cigarettes in airplanes. The story, as he told it, was that when passengers used to smoke inside airplanes, the tar from the cigarette smoke would accumulate on the inside surfaces of the fuselage and provide an extra layer of sealant. This was significant enough, he continued, that it could be observed by the amount of work necessary to maintain cabin pressure.

There may be a kind of truth to this. This is from a 1988 UPI article.

The recently imposed smoking ban on many commercial flights has had one distinctly unhealthy side effect—it snuffed out the most popular method mechanics used to spot cracks in aircraft fuselages.

Up until April when the government banned lighting up on flights of two hours duration or less, mechanics could count on tell-tale build-up of nicotine around cracks as air escaped from the passenger cabin when the plane pressurized after lift-off.

The cracks, which often are not dangerous as long as they remain small and do not link up, generally were repaired when the plane went in for maintenance.

But with the smoking ban, the nicotine is gone on many types of aircraft used in shorter flights such as DC-9s and Boeing 727s and 737s, and mechanics must now rely on much closer visual inspections and in some cases electronic inspections to detect cracks.

A blog with a more compelling version of this story with some details about an Aloha Airlines is here (they seem to have an expired SSL cert). And another with an interesting tangent involving Bertrand Russell.

Cigarettes have been proven beyond a reasonable doubt to be murderers, but for 26 people in 1948, they were a lifesaver. When a Norwegian domestic flight from Oslo to Hommelvik crashed due to high winds, 19 people died, but the 26 people sitting in the smoking section located at the back of the plane just happened to be in the right place to survive. Amazingly, 76-year-old philosopher Bertrand Russell was one of them. In his autobiography, he wrote that he insisted on a seat in the smoking section because “if I cannot smoke, I should die.”

I didn’t find much support for the initial claim, though it still seems plausible. But it does seem to be true that cigarettes played a role in airplane structural integrity prior to 1988.

But...

Dont smoke dont smoke dont smoke.”—Allen Ginsberg