Noise like a helicopter

My 2010 Hyundai Elantra with 6500 miles on it has started making a noise that sounds as if a helicopter is hovering overhead. This occurs intermittently when the A/C is running. Any ideas?

Look outside for a helicopter.
tell us more.

Where is the noise ?
Inside the dash ?
under the hood ?

The first thing I did was look for a helicopter, none found. Then I realized that the sound was coming from under the hood and disappeared when I turned off the A/C.

Get thee to the dealer for warranty repairs.

It’s related to the compressor or its clutch.
At only 6500 miles is it a new noise ?

With the hood up you can look for the noise source while someone else cylcles the a/c.
If it’s a compressor without enough oil in it when new, it won’t last long making this noise.
If it is debris trapped behind the clutch, remove the tumble weed.

If the Feds were following you they would be using one of those “silent” helicopters, really I saw it in a movie.

Is it that you are a bit hesitant to speak with a service Advisor about this?

We have no tumbleweed in Florida
We do have skeptical service advisors
I had planned to visit my dealer, just wanted some background info other than “there’s a funny noise” because the typical response is "we can’t reproduce the noise so we can’t help you"