It turns out you can check this on the official FAA website. Simply enter the airport code or the Flight Information Region (FIR) code, and you can query information for up to 50 airports at once. https://www.notams.faa.gov/dinsQueryWeb/ It really is convenient.

You can see that after entering the Fukuoka FIR (RJJJ), even U.S. military training information was found. Although this is flight simulation, let’s keep our distance. J2770/13 - MULTIPLE U.S.MIL ACT WILL BE CONDUCTED WI FUKUOKA FIR AS FLW, BOUNDED BY THE POINTS 2541N12852E 2548N12902E 2544N12926E 2544N13011E 2543N13036E 2541N13045E 2453N13004E TO POINT OF ORIGIN. ATC WILL NOT CLEAR NON-PARTICIPATING IFR FLT THRU THIS AREA. RMK/MISSION NAME:MIKE. FL055 - FL400, 0900/1500, 10 JUN 09:00 2013 UNTIL 14 JUN 15:00 2013. CREATED: 03 JUN 03:19 2013

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