Loud High Pitched Frequency Recurring Noise Near Roosevelt Island Tram & Queensboro Bridge Says Residents - Do You Hear It Too?

A Roosevelt Island resident asks:

Does anyone know what is the recurring noise we are hearing by the tram? We are in 405 Main and hear the noise periodically since last week. I had counted at some point and it had interval of 10 seconds.

My husband hears it to, so I'm not crazy; unless it makes two of us :)

 The Husband adds yesterday:

The first time I recall hearing the noise was on December 27th in the early afternoon - possibly around 1 PM or so. More recently it has been in the evening - last night it occurred at about 9:30 pm, and persisted for several minutes.

The noise starts as a loud constant high pitched tone that that slowly moves into an even higher frequency tone over the course of about 15 seconds. It stops briefly, and then starts over at the lower frequency tone several times. At first this cycle would repeat for 2-4 times, but last night it happened for a much longer period of time - it seemed like at least a few minutes. We hear the noise from any room with windows facing the Manhattan side of the river. Because it's such a high pitched tone, it's hard to triangulate whether it's north or south of us, but I'd estimate that it's somewhere between the Queensboro bridge and the construction zone near the subway station. We're at 405 Main St. and the rooms where we hear the tone have windows facing the East River directly across from 60th and 61st St. in Manhattan.

... Oh wow - it is literally happening right now (Thursday, Jan. 3rd) Here are the times and durations:

At 12:04 PM, for about 20 seconds
At 12:05 PM, for about 1 minute
At 12:07 PM, for about 30 seconds
At 12:20 PM for about 20 seconds
At 12:21 PM for about 20 seconds
At 12:23 PM for about 20 seconds
At 12:25 PM for about 20 seconds
At 12:28 PM for about 20 seconds
At 12:35 PM for about 20 seconds
At 12:36 PM for about 20 seconds
At 12:37 PM for about 30 seconds
At 12:39 PM for about 20 seconds
At 12:45 PM for about 30 seconds
At 12:47 PM for about 20 seconds
At 12:48 PM for about 20 seconds
At 12:50 PM for about 30 seconds
At 12:52 PM for about 10 seconds
At 12:54 PM for about 10 seconds
At 12:56 PM for about 5 seconds

and today:

... We heard it again last night and this morning for about 15 minutes. I opened my window a few times while the noise was occurring, and the sound actually gets nearly drowned out among the general background noise of the outdoors. My windows must do a good job blocking sound, but this particular frequency cuts right through it. For that reason, I'm not surprised that it's not being widely reported....

I asked the Tram Staff today if they knew anything about the noise and they had not heard anything.

There have been several instances in the past where loud noises from the Power Plants in Queens and Manhattan have spooked residents but they were heard by many.

Have you heard the noise - any ideas?