I live ten miles north of the Corvallis, OR airport, and lots of aircraft fly over my house. I've noticed that some aircraft make a distinctive whistle or whine as they approach the airport. What is making this noise? I would hazard a guess that maybe 1 in 20 do this. I haven't noticed a common denominator among the whistlers.

tom

I think some whistle due to wire bracing or wire antennas. My neighbors RV 9 whistles pretty loud.

My kitfox started whistling when I installed fairing on the wing struts. I attribute it to the open end of the aluminum cuff at the fuselage end of the strut. Like blowing over the top of an open beer bottle.

Commercial - Biz. jets - General Aviation?!?

EDIT of inadvertent double entry:

Definite differences in commercial traffic over Palo Alto into SFO .
Often change pitch in steps or stages.
Some headed to San Jose when the turn the runways around due to Wx.

Continental O-470's have that whine your talking about. I live under a traffic pattern as well and can tell that engine from the dinner table.

My RV9 whistles at certain speeds. I'm told it is airflow over the openings to the elevator attach points. Doesn't happen all the time (or maybe I can't hear it all the time).

Greg

Piper retractables whistle when their gear is down on approach, so do some Cessna 180/185's with BAS pull handles in the rear fuselage.

Hamish

Lots of planes whistle. It's usually from an opening or "pocket" somewhere on the airframe, like extended landing gear on retract planes, and the elevator attach points Greg mentioned above on his RV-9. I have a lot of time flying in a craft with slats. Those whistled and hissed enough to drive one mad. The wire braces on the Stearman whistle quite a bit, too. When I used to fly RC models a lot, I remember there being one brand that had a certain gap between the ailerons and wings which acted like a fipple on a recorder. Those planes squeaked like rubber ducks.

For Wannabe: light planes like the ones folks have already answered about.

For the folks answering that their plane makes that noise: can you hear this noise in the cockpit?

Thanks all for the answers. I've wondered about this for years, and figured it had to be a variety of causes because the whistles are quite varied.

tom

Usually the loudest whining comes from the pilots: "my coffee isnt hot", "the winds are high", "The other plane isn't using the right radio terminology" etc

Savannah-Tom wrote:For the folks answering that their plane makes that noise: can you hear this noise in the cockpit?
tom

Yes, quite well. On the first flight after installing the wing strut fairing when I first heard it I thought I had forgot to secure something when I spread the wings after trailering to the airport. Cruise speed with the fairing increased from 75 mph to 85 mph so I was wondering about the effects of the extra speed too. Then remembered the openings on the fairing cuff and quit worrying.

Some pilots are just happy. But sheesh,...I thought it was more than one in ten.

Hell, those old airplanes are just singing the songs of their people.

Every beater I've ever flown has always "talked" to me as I went through the stages of slowing down and configuring for a landing. If my eyeballs and seat of the pants ever fail me, I can still listen to the singing to get myself safely on the ground.

Gump

Mine does this, it whines when I am close to the stall.

That noise happens because I put my air vent intakes for the cabin on the leading edge, but I put them a little too high. So at high angles of attack, the air rushes over them on it's way up the wing, and I imagine that causes little eddies inside the vent which create the humming / whining sound.

The noise is a good backup stall warning, if nothing else. But also a little annoying when I am trying to concentrate on a short landing.

I saw one that whistled because the owner had installed a "deer whistle" on the cowling's air intake area... He operated the plane in "deer country" and had several close calls... No idea if it works or not.

GumpAir wrote:Hell, those old airplanes are just singing the songs of their people.

Every beater I've ever flown has always "talked" to me as I went through the stages of slowing down and configuring for a landing. If my eyeballs and seat of the pants ever fail me, I can still listen to the singing to get myself safely on the ground.

Gump

I must agree!
When I was learning to fly in a Stearman, I was always taught to listen to the whistle, it will tell you a lot about the state of flight, along with the sound/strain level of the engine.

Since the question was asked if I can hear the whistling from the cockpit, yes, in every whistly plane I fly, I can hear it fairly clearly unless I'm borrowing a noise reduction headset.

Headoutdaplane wrote:Usually the loudest whining comes from the pilots: "my coffee isnt hot", "the winds are high", "The other plane isn't using the right radio terminology" etc

I can relate to that one Only had a few over the years They didn't last long ...

About 12 years ago or so, I owned a single seat Himax ultralight. It would whistle when I was coming in to land with the throttle at idle. I never heard it in the plane myself, but you can plainly hear it in this utube video of it. Jim Chuk
https://www.youtube.com/watch?v=GAI3zrd0ZPk

GumpAir wrote:

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Every beater I've ever flown has always "talked" to me as I went through the stages of slowing down and configuring for a landing.

Man...that sounds like most of the beat up cars I drive. Of course there is also that added element of the smell of oil, tranny fluid, & engine coolant. Gauges and seat belts are for sissies.