Is Friday the 13th an unsafe day to fly? Enough travelers think so that in some places, plane tickets are cheaper on Friday the 13th. One reason may be the high-profile Uruguay Air Force passenger flight crash in the Andes on Oct. 13, 1972. But at least one Friday the 13th has come and gone every year since, most with no disasters.

If you’re still nervous, you should know that on Friday, Oct. 13, 2017, a flight numbered 666 took off at 13:00 and flew straight to HEL (Helsinki). Everything turned out fine. In fact, the airline turned it into a bit of a joke.

You see, Finnair scheduled a flight from Copenhagen, Denmark, to Helsinki, Finland, that often got the number 666—ironic because Helsinki’s abbreviation is HEL.

Not just that, but the flight has occurred on a Friday the 13th many times—21 to be exact—and always without incident.

But perhaps Finnair worried it was losing ticket sales. Or maybe it just added some flights and used “666” for a different route. Whatever the reason, the Oct. 13, 2017, Flight 666 would be its last to HEL. So Finnair decided to send the route out with a bang.

It requested a 1 p.m. takeoff time from air traffic control. That meant Flight 666 took off at 13:00. It had no problems and landed ahead of schedule. But on the tarmac waiting for the passengers sat a unique black Helsinki Airport bus: The livery showed a guitar player and the words, “Hard rockin’ HEL.” You can see an image in the X post embedded below:

Hi there! We have something better in opur mind: our heavy metal themed bus will give one HEL of a ride for #AY666 passengers! pic.twitter.com/Ai8FVqv4qq

— Helsinki Airport (@HelsinkiAirport) October 13, 2017