Japanese Nippon Cargo Airlines grounded its fleet of freight planes after transport ministry inspectors discovered inaccuracies in aircraft maintenance records.
The inspection began last month after it found that cargo operator failed to report many incidents that caused serious damage to its planes.
The inspection uncovered inaccuracies in aircraft maintenance records and considering taking disciplinary measures against the company.
The records in question said that the amount of lubricating oil supply injected into a plane’s wings was less than the actual amount.
Nippon Cargo grounded all of its 11 jets from Saturday 16, June 2018.