Why you can't make a passenger plane out of a bomber

Here's an example of how thinking about economics can be helpful in evaluating claims that, at first sight, don't have much to do with economics. Do you remember the Polish presidential aircraft crash of April 10, 2010? If not, here's what happened. On April 10, 2010, the Polish presidential aircraft, a highly customized version of Tu-154 (a Russian-made commercial airliner that began service in 1972) crashed on approach near a small military airport in Smolensk, Russia, killing all 96 people on board. Among the victims were the President of Poland Lech Kaczynski, his wife, the military joint chiefs of staff, the director of Polish central bank, and many other VIPs.

Recently, the late President's brother and leader of Poland's largest opposition party Jaroslaw Kaczynski, gave an interview in which he talked about the crash and the ongoing investigation thereof. One of the things that Kaczynski is wondering aloud about is the extent of damage suffered by the aircraft's fuselage. The plane did not lose lift until it was 20 meters (about 66 feet) above ground, and yet it completely shattered on impact. Kaczynski suggests that this should not have happened because the design of Tu-154 is based on a Soviet bomber and its fuselage is therefore much stronger than that of a typical airliner.

Now it's certainly true that the presidential Tu-154 was in fact structurally stronger than your average commercial aircraft. VIP planes are highly customized with safety in mind. Air Force One is technically a Boeing 747-200, but it's really modified beyond all recognition. So I am not going to talk about that particular Tu-154; instead, I want to criticize the claim that the structural fuselage strength features of a regular, mass produced Tu-154 are adapted from a bomber. You don't need to know much about aircraft engineering to realize that it's unlikely to be true. All you need to know is that commercial airlines have to be profitable while the air force does not.

Passenger aircraft are designed to be sold to commercial airlines. The airlines have to make a profit operating them. That means the aircraft they use have to be fuel-efficient. An aircraft design that puts too much weight on fuselage strength is likely to make the aircraft too heavy. Too heavy means it's using too much fuel to pay for itself. Bombers, on the other hand, don't have to pay for themselves. Designers of bombers can afford to make them able to withstand high-energy impact. Designers of commercial jets cannot.