I'm watching ADSBexchange too.

It's eerie seeing the total number of aircraft tracked decrease. I put on a filter for 1000' to 80000', to exclude aircraft on the ground, and the number was around 12K when I started watching. It's down to just over 9.4K now. Wild.

Now under 8k

To be fair, above 40AGL is relatively high for most airliners. Most are between 30 and 40.

FL400. 40 AGL is doable for almost all airliners ;)

Thanks. Meant to slap a k on that 40.

Actually that would be quite challenging over most terrain.

Absolutely tons between 10K-20k, though.

This tracks with what I has seem elsewhere. I don't have the details handy now, but the communication system used for long range handoffs for flights above 18,000 ft seems to be what is impacted. Keeping planes below that deck would keep them bouncing more frequently between shorter range towers but at least still tracked and in communication.

[delayed]

My view on ADSBexchange is centered on CMH, zoomed out to Washington D.C. to the east, and filtered by 18K up I've got 142 aircraft.

I'm also near Detroit and am watching the trackers and I'm pretty sure I just saw N831AK take off from Troy Oakland in violation of the grounding order. I wonder how common that is.

I live in the general area of you too. Nice to know that there are Detroiters on here.

Looks like some flights are taking off from JFK https://globe.adsbexchange.com/?icao=4cc58a

It could be the flights that are heading directly away from US airspace over the atlantic to free airport space for other planes?