Moderators: richierich, ua900, hOMSaR

 
PhotographyNYC
Topic Author
Posts: 1
Joined: Tue May 19, 2020 7:56 pm

McDonnell Douglas PA system

Tue May 19, 2020 8:00 pm

Whenever I fly on a MD-80 or 88 or 90 (especially delta) whenever the intercom system is in use there’s A continuous whiny sound in the background, what is that, and why is it only on MD airplanes?
Last edited by atcsundevil on Tue May 19, 2020 8:03 pm, edited 1 time in total.
Reason: Edited spelling in title; non descriptive thread title
 
CoronadoConrad
Posts: 10
Joined: Sat Jul 06, 2019 9:25 am

Re: McDonnell Douglas PA system

Tue May 19, 2020 9:42 pm

Interference from the 400Hz AC system, aircraft with better shielding/filtering might not make this sound over the PA.

Who is online

Users browsing this forum: Airliner1973 and 50 guests

Popular Searches On Airliners.net

Top Photos of Last:   24 Hours  •  48 Hours  •  7 Days  •  30 Days  •  180 Days  •  365 Days  •  All Time

Military Aircraft Every type from fighters to helicopters from air forces around the globe

Classic Airliners Props and jets from the good old days

Flight Decks Views from inside the cockpit

Aircraft Cabins Passenger cabin shots showing seat arrangements as well as cargo aircraft interior

Cargo Aircraft Pictures of great freighter aircraft

Government Aircraft Aircraft flying government officials

Helicopters Our large helicopter section. Both military and civil versions

Blimps / Airships Everything from the Goodyear blimp to the Zeppelin

Night Photos Beautiful shots taken while the sun is below the horizon

Accidents Accident, incident and crash related photos

Air to Air Photos taken by airborne photographers of airborne aircraft

Special Paint Schemes Aircraft painted in beautiful and original liveries

Airport Overviews Airport overviews from the air or ground

Tails and Winglets Tail and Winglet closeups with beautiful airline logos