April 30, 2018
A tiny air deflector mounted inches from vent holes on aircraft wings can cut noise 7-30 miles upon decent. This small air deflector, or ‘vortex generator’, serves to decrease the distinctive high-pitched noise from arriving Airbus A-320A (single-aisle) aircraft by blocking the circular air pressure over the vents on the underside of the aircraft wings before its landing gear and flaps are deployed.
Although standard on newer Airbus aircraft, older aircraft need a vortex generator retrofit to eliminate the whistling noise. Some communities, particularly around Boston’s Logan Airport, have voted to send letters to airlines operating A-320 series aircraft imploring them to retrofit older model Airbus aircraft. The request to retrofit (although not mandated by the FAA), serves as an immediate and inexpensive solution to reducing residential noise exposure. The cost to install a vortex generator on one aircraft is $5k (parts and labor).
A vortex generator requires no big shift in technology or major manufacturing investment. A 5-cm triangular piece of aluminum sheet metal directly upstream of the vents diverts airflow and stops the whistling noise; a decrease of approximately 6 decibels. The negation of those tones can be the difference between annoyance and calm to human perception.
Currently, Europe’s second largest airline—Lufthansa, retrofitted their A-320’s with vortex generators, and have required them on all new aircraft since 2014. Air France has made a similar commitment. Following their lead, British Airways and EasyJet installed modifications to their fleets in 2016. In the US, United Airlines began installing vortex generators in 2017.
All remaining US carriers have yet to announce the vortex generator retrofit, and without a mandate from the FAA, delay and even avoidance seem inevitable. Importantly, the smallest carriers such as Allegiant, Frontier, Jet Blue, Spirit, and Virgin compose the greatest number of Airbus A-320’s in their fleets. (100% of Frontier, Spirit, and Virgin aircraft are A-320’s.) The larger airlines—American and Delta, have smaller concentrations.
According to the February 2018 O’Hare Noise Compatibility Commission (ONCC) Monthly Noise Report, there were 152 average daily arrivals into O’Hare by Airbus A-320 aircraft. Twenty of these flights were overnight.
In the near term, FAiR NFP will be contacting these airlines to determine the prevalence of vortex-equipped and non-equipped A-320’s operating at O’Hare. The goal of this communication will be to encourage these remaining airlines to install vortex generators on their A-320 series aircraft. The vortex generator is a rather simple means to dampen noise, and represents a straightforward commitment by the airlines to balance the interests of aviation with the concerns of residents around O’Hare. FAiR NFP will be leading these coordination efforts on behalf of our affected members.