2 things come to mind. Both in the woods, both late at night.

The first, maybe 5-6 years ago in the woods outside of Bald Eagle State Park. A group of friends all drinking around the campfire, being noisy and rambunctious as people who drink do. I am no an imbiber, but was happy to hang. Around midnight I looked up, and hovering about the trees was.... a thing. A plane of some kind? the strangest thing was, it was dead silent. Took off with a woosh and a swiftness I've never seen from a plane since. Best explanation I can come up with is that there are Lockheed Martin facilities in the general area, so it may have been an SR-71 of some kind. Have never been able to confirm, because asking a group of drunks "Do you see that?" did not get the results I needed.

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The second, is almost the exact opposite. I was camping at Hertlein while hiking the AT with my brothers. At around 2 am, a noise so cacophonous I couldn't hear my brother whom I was sharing a tent with enveloped us. It lasted for around 5 mins, then disappeared. The next morning we had the "did you hear that?" conversation. All three of us heard it, none of us could come up with a decent explanation and have not talked about it since, since none of us was brave enough to get out of the tent and look .