A Japan Airlines jumbo jet made six international flights between mid-July and mid-August without one of two legally required items of emergency equipment, aviation industry sources said Friday.
The Civil Aeronautics Law requires aircraft to be equipped with two emergency locator transmitters (ELTs) when making long flights over the sea.
JAL revised its workers' manual in September last year to simplify maintenance work, stipulating JAL aircraft must carry two ELTs on all such flights, the sources said.
But maintenance workers erroneously followed an old manual and removed one of the ELTs from the Boeing 767-300 on July 13. The jet made three round trips to Palau and another destination during the one-month period.
The Transport Ministry has admonished JAL over the case, the sources said.
An ELT automatically emits two different emergency radio waves when an aircraft makes an emergency landing at sea.
The cylinder-shaped device measures 15 cm in diameter and 80 cm in length.