Editor's Note: In the following article, we let the Federal Highway Administration's "unofficial historian" get something off his chest. He needed to vent.

I don't know if 10 percent of the Russian government's income comes from the sale of vodka. I don't know if a cow can go upstairs, but not downstairs. And I certainly don't know if a duck's quack doesn't echo.

But I do know the following statement is false: The Eisenhower Interstate Highway System requires that one mile in every five must be straight. These straight sections are usable as airstrips in times of war or other emergencies.

False though it is, this "fact" has become a fixture of Internet Web sites with names such as "You Probably Didn't Know That ..." and "Weird Fact Heaven."

For a historian, even an unofficial one, who believes that a fact should be, by definition, factual, what is particularly frustrating is that everyone seems to know this "fact." People — including those whose eyes glaze over if I even mention Gen. Roy Stone¹ or the vitally important statewide highway surveys of the mid-1930s² — get a twinkle in their eye when I mention the Interstate Highway System. "Did you know," they say to me cheerily as I grit my teeth, "that one in every five miles ..."

When that happens, I feel like the staffer at the information desk of the Smithsonian Natural History Museum who told me the most frequently asked question she receives is, "Where's the rest room?" Like her, I try to reply patiently without rolling my eyes or groaning, and I try not to give the impression I've heard this "fact" once or twice or maybe a hundred times before.

As with Dracula, it is very difficult to put a stake through the heart of this "fact." It's like the "urban myths" we have all heard — untrue things that people nevertheless believe. For example, that alligators thrive in our sewer systems. Now there are "Internet myths" — untrue claims that bounce around the Internet like juicy gossip with reality never having a hope of catching up with them. That's what happened with the one-out-of-five claim about airplane use of the Interstate Highway System. (Next, it will probably show up on the ABC game show "Who Wants to Be a Millionaire?," where 20 million people will see it — maybe as the $200 question.)

I have no idea where the one-out-of-five claim originated. Perhaps it is giving too much credit to whoever originated this "fact" to suggest that it began with a misreading of history. Under a provision of the Defense Highway Act of 1941, the Army Air Force and the Public Roads Administration (PRA), now the Federal Highway Administration, operated a flight strip program. In a 1943 presentation to the American Association of State Highway Officials, Commissioner of Public Roads Thomas H. MacDonald explained how it worked.

"A flight strip consists of one runway, laid down in the direction of the prevailing wind, and a shelter with telephone for the custodians at the site and for itinerant flyers in an emergency. Fuel storage facilities are not provided unless airplanes are based there permanently. Instead, oil companies will keep stocks of aviation gasoline at gas stations along the highway and truck it to the flight strip as it is needed."

The flight strips were designed for easy access to public highways and to provide unmistakable landmarks that could be followed easily by a pilot. Flight strips varied in size. The smallest — 150 feet (46 meters) wide and 4,000 feet (1,220 meters) long with the length increased by 500 feet (152 meters) for each 1,000 feet (305 meters) of elevation — were designed for tactical aircraft such as medium bombers. A larger flight strip could accommodate heavy bombers such as the B-17 and B-24, while still larger strips were designed for heavier classes of aircraft.

The benefits weren't expected to be entirely military. As MacDonald explained, "The close coordination of our highways and airways is becoming a vital necessity to assist the economic growth of this country."

In that spirit, Congress considered including a flight strip program in the Federal-Aid Highway Act of 1944 — the law that authorized designation of a "National System of Interstate Highways." However, the 1944 act did not include the flight strip program.

Some references to the one-out-of-five "law" attribute it to the Federal-Aid Highway Act of 1956. The 1956 act launched the Interstate Highway Program by creating the Highway Trust Fund as a funding mechanism and by committing the federal government to build what became the 42,800-mile (68,880-kilometer) Eisenhower Interstate Highway System (now essentially complete). President Dwight D. Eisenhower fully supported the Interstate Highway System as vital to our economy, safety, relief of congestion, and defense. However, he didn't propose a one-out-of-five-mile rule, and Congress didn't include such a requirement in the 1956 Act. The one-out-of-five rule was not part of any later legislation either.

OK, OK, I sense eyes glazing over again. Readers are probably thinking, "Brace yourself. He's going to mention Gen. Roy Stone again."

Don't panic. Here's the end of this article.

In the hope that this article will find its way into Public Roads and Public Roads Online and will be seen by Internet surfers, I will conclude by saying that, for all I know, there are 293 ways to make change for a dollar, snails can sleep for three years without eating, and an ostrich's eye is bigger than its brain. BUT NO LAW, REGULATION, POLICY, OR SLIVER OF RED TAPE REQUIRES THAT ONE OUT OF FIVE MILES OF THE INTERSTATE HIGHWAY SYSTEM MUST BE STRAIGHT.

Trust me on that. Please!

Editor's Note: Mr. Weingroff reports that his blood pressure improved considerably shortly after writing this article.

Richard F. Weingroff, who works in the Federal Highway Administration's Office of Infrastructure, is an information liaison specialist who also doesn't like being asked, "So what the heck is an information liaison specialist anyway?"

¹For those readers who don't know who Gen. Roy Stone is, don't worry. It never comes up in conversation.

² These surveys were very important because they provided the ... oh, never mind.