Yup, it happened. Again. Yet another Chinese traveler has been detained after throwing coins just before boarding a plane as a way of praying for a safe flight.

This latest incident occurred on Tuesday at the Wuhan Tianhe International Airport. Surveillance camera footage posted online shows a man in a red jacket flipping coins off a gap in the air bridge before stepping onto the plane.

The move was noticed by airport staff who detained the 31-year-old traveler, surnamed Xia, and investigated the tarmac where they discovered three one-yuan coins. After a 30-minute delay, the Hainan Airlines flight took off for Urumqi.

Not on the plane was Xia. Upon questioning, he told police that throwing the coins had been his mother-in-law’s idea, believing that it would make for a safe and smooth journey, according to the local Chutian Metropolis Daily. Xia was traveling with his wife and their four-month-old daughter.

He further described how upon arriving at the airport, he found that he only had a single one-yuan coin, and so went to a shop to get some more change, reasoning that one coin would not be enough to ensure their safety. He also added that he did not believe that throwing the coins in the terminal would be effective, and so he waited until he got his opportunity on the airbridge.

Xia has been detained for 10 days. It’s not clear if he will face additional punishment. His wife and daughter went without him to Urumqi. Their plane landed there safely.

This is now at least the sixth time that this kind of thing has happened in China in the past two years. Somehow, it’s only becoming more and more frequent. The first such incident occurred in June 2017 when an 80-year-old threw 1.7 yuan in change into the engine of a China Southern Airlines plane at the Shanghai Pudong airport to “pray for a safe flight,” thus causing a five-hour delay and 1 million yuan in damages. Despite this hefty bill, the woman was not charged with any crime due to her old age. This was followed several months later by a 76-year-old granny flinging coins into the engine of a Lucky Air flight from the Anhui city of Anqing to Kunming. The woman was detained but appears to have never been prosecuted. Then, at the Anqing airport in January, a China Eastern Airlines flight was delayed when workers found two coins lying on the ground near the plane’s engine. When questioned, none of the passengers fessed up to having done the flinging. While elderly travelers may seem the most likely suspects, it appears that not only the old are superstitious when it comes to flight. In February, again at the Anqing airport, a 28-year-old male passenger was taken into custody after trying to chuck coins into the engine of a Lucky Air plane while boarding, believing that they would keep the flight safe from hazard. Finally, last month, yet another Lucky Air flight was delayed when two female passengers were spotted chucking coins off the airbridge before getting on their plane at the airport in Jinan. Both of the women were reported to be in their mid-twenties.