It has been revealed that a Japan Airlines copilot was replaced after failing a preflight alcohol test at an airport in southwestern Japan.
The 54-year-old male copilot was to board a flight from Kagoshima to Tokyo on Saturday.
Japan Airlines says up to 0.09 milligrams of alcohol per liter were detected in his breath.
Japan's government rules ban any pilot or copilot from boarding a flight if any alcohol is detected.
The copilot has reportedly explained he mistook a cup of sake for water and drank 30 to 50 milliliters of it while having lunch at his hotel about two hours before his scheduled flight.
Japan Airlines apologized for the incident, which follows a series of alcohol test failures. It has again promised measures to prevent a recurrence.
Families of victims of the 1985 Japan Airlines crash that killed 520 people are angry at the latest alcohol incident.
Kuniko Miyajima, who heads a group of victims' families, said pilots had been supposed to remember the crash and renew their safety awareness as the day of the crash, August 12, was approaching.
She described the copilot's drinking two days before that day as a betrayal of the families' continuous calls for flight safety. She said the airline bears a heavy responsibility.