An investigation has been opened into a “serious” incident at Nantes Atlantique airport, where reports suggest that pilots from the regional Air France airline Hop made a major altitude error.
Civil aviation safety agency Le Bureau d'enquêtes et d'analyses pour la sécurité de l'avion civile (BEA) is investigating the incident, which took place on October 20, 2021.
The investigation is centring on an alleged error committed by the pilots of a Hop plane flying between Lyon (Rhône) and Nantes (Loire-Atlantique).
Hop is a regional airline, whose parent company is Air France KLM. It serves more than 140 destinations in France and Europe and is based at Nantes Atlantique airport.
The BEA has stated that analysis suggests that a Minimum Safe Altitude Warning (MSAW) alert went off when the aircraft, a Bombardier CRJ 1000, was approaching the runway, meaning that there was a risk of crashing into the ground.
This means that the aircraft was flying far lower than it should have been, due to a misunderstanding of a message by the pilots. Air traffic control had requested a descent to 3,000 feet and indicated a QNH, the altimeter setting required, to read an altitude of 1,002.
In the cockpit, the crew "read back" a QNH of 102 [instead of 1,002]; much too low. The error was quickly corrected, however, and the plane landed safely.
The BEA is now investigating how the error occurred in a bid to stop it from happening again.
The incident has echoes of a previous severe issue at Nantes in 2004, when a plane belonging to the Egyptian company Luxor Air mistook lights leading to the Tour Bretagne (Brittany Tower) in central Nantes as the airport runway upon its approach, and “brushed” against the tower in correcting the issue.
It had 104 passengers and eight crew on board.
The main approach to Nantes Atlantique airport requires planes to fly over the city of Nantes, an issue that was initially addressed in a proposal to move the main airport to Notre-Dame-des-Landes instead.
However, in 2018, this idea was abandoned and the current platform and runway were redeveloped instead.