Major European Airbus operators take steps to avoid A320 whistle noise nuisance
Lufthansa A320 with vortex generator mounted forward of underwing cavity for the fuel over-pressure protection system
Wed 5 Aug 2015 – Lufthansa has now retrofitted the 100th aircraft belonging to its Airbus 320 family fleet with a noise-reducing component called a vortex generator. Peculiar to this aircraft type, a distinctive high-pitched noise – similar to the sound created when blowing over the mouth of a bottle – is created when air passes over circular pressure equalisation vents for the fuel tanks located under each wing, just before landing gear and flaps are deployed for landing. Complaints have been made across the world by residents surrounding airports – the noise can emanate up to some considerable distance from touch-down. After a number of years of research by Lufthansa and the German Aerospace Center (DLR), a simple 5cm piece of sheet metal mounted upstream of the vents has shown to solve the problem. Other airlines are now carrying out programmes to retrofit their narrow-body Airbus aircraft with the component, including Air France, British Airways and easyJet.
Late last year, Lufthansa became the first airline to start retrofitting vortex generators, which generate an air vortex over the vents to effectively prevent the annoying tones. According to measurements taken by the airline and DLR, the component can also reduce the overall noise level of the aircraft when landing by up to four decibels at distances of between 10 and 17 kilometres away from the airport. In total, Lufthansa is equipping 157 of its A320 family fleet with vortex generators, which are being manufactured by UK aerospace engineering company Supercraft. The first new A320 aircraft with the component pre-installed entered service with the airline in February 2014.
British Airways says it is fitting the modification on up to 130 of its aircraft in a programme that is expected to start this October after the busy summer season. “We are still finalising the exact modification programme for each aircraft,” said a spokesman for the airline.
EasyJet, one of Europe’s biggest operators of the model with over 230 A319/A320 aircraft, has committed to retrofit 197 aircraft not already equipped with vortex generators by March 2018.
“We plan to frontload the programme so the benefit will be felt more quickly by residents near our airports,” an easyJet spokesman told GreenAir. “Accordingly, we expect to have retrofitted 100 aircraft by June 2016. This will be in addition to the 41 new aircraft, pre-fitted with vortex generators, which will also be in the fleet by that date.
“We believe this plan addresses the concerns on this noise issue and provides reassurance that easyJet is committed to reduce the impact of our aircraft. Over the next few years, easyJet will take delivery of over 150 new aircraft, 100 of which will be new-generation A320neo aircraft, which will have lower noise levels than today’s aircraft.”
Airbus itself stated it could not comment on customer decisions as to whether or not they should retrofit their aircraft with the component, which it describes as an air flow deflector. “As for any option, it is up to our customers to communicate their preference,” said the manufacturer. “As part of our incremental innovation strategy, Airbus has developed the air flow deflector for the A320 family, which can significantly reduce the specific noise at distances between 15 and 40 kilometres from the runway.”
As of 31 May 2015, a total of 6,581 Airbus A320 family aircraft have been delivered, of which 6,315 are in service worldwide. In addition, another 5,123 airliners are on firm order.
The 5cm-long vortex generator (photo: Supercraft):