Aer Lingus failed to report an incident, where an aircraft carrying 146 people banked sharply on its approach to Dublin Airport, to the authorities within the time demanded by safety regulations, it has emerged.Safety rules require airlines to inform the Irish Aviation Authority (IAA) of certain incidents involving their aircraft within 72 hours of an incident occurring, an obligation known as mandatory occurrence reporting.Aer Lingus did not inform the authority of an incident where an Airbus carrying 146 people diverted sharply from its approach to landing at Dublin Airport until two months after it happened, according to the Department of Transport’s Air Accident Investigation Unit (AAIU).The AAIU report on the incident, published in recent days, says that the incident occurred on January 14th last year, but was not reported until March 18th, despite being subject to the mandatory reporting obligation.According to European regulations, incidents of the type outlined in the AAIU report “should be reported within 72 hours of the occurrence, unless exceptional circumstances prevent this”, a Department of Transport spokesman said.The two-month delay meant that neither the cockpit voice recorder, which records pilots, nor the digital flight recorder, were available to AAIU investigators.Aer Lingus investigated the incident itself, as it is required to do, but did not believe at the time that it warranted mandatory occurrence reporting, according to a source familiar with the issue.As a consequence, the airline subsequently decided that the incident should have led to a mandatory report. It then provided details to the AAIU, which takes responsibility for investigating incidents involving commercial aircraft.The air accident unit states that the Irish Aviation Authority received a report of the incident through a European Aviation Safety Authority internet portal.That portal allows airline workers, passengers and airlines to make what are called “voluntary” reports to the European authority.“Following further enquiries, and upon receipt of an air safety report from the operator [Aer Lingus], the AAIU commenced an investigation,” says the unit’s report.No one was injured during the incident and the AAIU made no safety recommendation.The Airbus A320 had been flying from Faro in Portugal to Dublin with 140 passengers and six crew. It approached Dublin from the south around lunchtime and turned left on to the inbound course agreed with air traffic control.However, it ended up to the south of this course, and had to turn right, banking at an angle of 44 degrees as it did so.After correcting, the aircraft lost airspeed twice as it flew east away from the airport, before climbing, turning around and descending on to the designated runway without any further incident.“Aer Lingus acknowledges the publication of the AAIU report and the fact that there are no safety recommendations arising from it,” an airline statement said.According to the department’s spokesman, the AAIU chief inspector can investigate “any incident that is not a serious incident” where they believe significant air safety lessons can be drawn from doing so.The unit’s report points out that safety investigations are not concerned with apportioning blame or liability. “The sole objective of AAIU safety investigations and final reports is the prevention of accidents and incidents,” it says.