And it's people like Walter Lees of Pedros road who are helping to break down the superstition of misfortune that has always surrounded this combination of day and date.
Lees remembers another Friday, May 13, as just about the luckiest day of his life. In fact, had he been anything but lucky, it may well have been the last day of his life.
This was in 1924, Lees was a test pilot for the budding, but awfully young, aviation industry in the now famous place of its nativity, Dayton, Ohio.
As one of the daredevils of his day, Lees just never wore a parachute on his test flights.
"We didn't have much room to begin with in those little cockpits," Lees recalls, "and I never felt comfortable with a chute on."
"I had two planes to test that day -- a German ship and an Italian job. The German plane I had taken up the previous summer and it didn't worry me, but the Italian baby -- I was a little skeptical of it."
The only trouble, parachutes were not easy to come by in those days. It just happened that Lees, being a reserve officer in the Air Service, was able to borrow one from a supply officer.
After putting the parachute on, Lees, for some reason or other, decided to take the German plane up first. He was putting it through the paces, doing all the maneuvers of the day, when suddenly the plane went into an uncontrollable barrel-roll and began nosing earthward.
Lees remembered the last time he saw the altimeter, it showed a scant 200 feet. Bailing out in those days consisted of standing up in the open cockpit and pulling the ripcord. This Lees did -- as soon as it occurred to him that he was wearing a parachute.
He figures it was another 150 feet before his 'chute' "took hold," and the parachute had only 50 feet in which to break his fall.
It was enough. He landed hard, but without breaking any bones. There was no apparent injury, though Lees believes a hip condition he developed in recent years may have been caused by damage from that jump.
The former test pilot still holds a Class C world's record for an endurance flight over Florida in 1931. During World War II, he was called into service with the Naval Air Force and served as a Lieutenant Commander.