Skymark Airlines Inc. said Wednesday its 8:40 a.m. flight from Tokyo's Haneda airport to Sapporo in northern Japan was delayed for 23 minutes after alcohol was detected on the breath of the plane's American pilot.

Japan's two largest airlines -- Japan Airlines Co. and All Nippon Airways Co. -- have been hit by similar alcohol issues recently, leading the government to consider tightening rules on drinking by aviation staff.

According to Skymark, the 49-year-old pilot, who was scheduled to take charge of Flight 705, tested positive for alcohol in a test conducted about 50 minutes before departure.

The airline tried to conduct a more detailed examination with digitalized equipment to see if the alcohol level was above 0.15 milligrams of alcohol per liter of breath (the minimum mark set by Skymark to ban a pilot from going on board) but a member of staff did not know how to use the device, leading the airline to prioritize the replacement of the pilot.

The pilot told a hearing that he drank seven 500-milliliter cans of beer between 3 p.m. and 7 p.m. on Tuesday.

When he was eventually tested at 9:37 a.m., he was found with 0.10 mg of alcohol per liter of breath, making it difficult to confirm whether he had been in a state of violating the in-house regulations at the time of pre-departure testing, it said.

Skymark prohibits its pilots from drinking alcohol 12 hours before getting on their flights. It has not had to replace a pilot due to alcohol detection over the past three years, it said.

A JAL co-pilot was arrested by British police for being about 10 times over the legal limit under British aviation law after he drank the night before his London-Tokyo flight on Oct. 28, while an ANA pilot became unwell after drinking in Okinawa, causing flight delays on Oct. 25.

Following the series of drinking incidents, the Ministry of Land, Infrastructure and Transport and Tourism has said it will set up a panel to strengthen regulations on drinking by aviation staff.

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