The Airbus A320 built before 2014 emit a whine which can be heard up to 20 miles away. It is estimated that 35% of flights going into SFO need the retrofit. The retrofit is a low cost (3-5k) procedure that could reduce the noise of these planes by half (2 to 11 db)
European carriers have already started retrofitting the A318, A319, A320 and A321 which are affected by this whine. Lufthansa has already invested in these upgrade for all the A320 airbuses in their fleet.
SFO Noise abatement estimates that it would cost $3k to retrofit the A320 and about 10 man hours and partial defueling of the aircraft. This low cost investment could significantly reduce the noise for all in the Bay Area and beyond. A major airline has committed to the retrofit but we need all planes to be retrofitted immediately to provide noise relief to all.
The A320 series is widely used and retrofitting these planes could have a drastic impact on our region. By 2019 SFO is expecting over 150,000 annual operations of the A320 series: 98,915 annual operations of the A320, 41,975 Operations of the A319 and 10,585 Operations of the A321.