{"schema_version":1,"airport":"BTM","entries":[{"cycle":"2026-09-03","from_cycle":"2026-08-06","id":"e3e25d975a80","priority":"action","category":"remark","kind":"removed","summary":"remark removed: COMMUNICATIONS PRVDD BY GREAT FALLS RADIO ON FREQ 122.3 (COPPERTOWN RCO).","source":"ATC_RMK","original":"COMMUNICATIONS PRVDD BY GREAT FALLS RADIO ON FREQ 122.3 (COPPERTOWN RCO)."},{"cycle":"2026-09-03","from_cycle":"2026-08-06","id":"f3e732931e4b","priority":"fyi","category":"frequency","kind":"removed","summary":"flight service (FSS) 122.2 via the Butte outlet no longer available","source":"FRQ"},{"cycle":"2026-09-03","from_cycle":"2026-08-06","id":"5e9ba951ea16","priority":"fyi","category":"frequency","kind":"removed","summary":"flight service (FSS) 122.3 via the Coppertown outlet no longer available","source":"FRQ"},{"cycle":"2026-09-03","from_cycle":"2026-08-06","id":"26ea950bdd2d","priority":"fyi","category":"remark","kind":"changed","summary":"remark updated: FOR CD CTC SALT LAKE ARTCC AT 801-320-2568.","source":"APT_RMK","original":"FOR CD CTC SALT LAKE ARTCC AT 801-320-2568.","fields":[{"field":"REMARK","old":"FOR CD IF UNA TO CTC ON FSS FREQ, CTC SALT LAKE ARTCC AT 801-320-2568.","new":"FOR CD CTC SALT LAKE ARTCC AT 801-320-2568."}]},{"cycle":"2025-05-15","from_cycle":"2025-04-17","id":"1ef005e5ad5c","priority":"fyi","category":"airport","kind":"changed","summary":"cold temperature airport (altitude correction at or below): -25C -> -24C","source":"APT_BASE","fields":[{"field":"CTA","old":"-25C","new":"-24C"}]},{"cycle":"2025-05-15","from_cycle":"2025-04-17","id":"3bcfedcb1a45","priority":"fyi","category":"remark","kind":"changed","summary":"remark updated: Cold temperature airport; altitude correction required at or below -24C.","source":"APT_RMK","original":"COLD TEMPERATURE AIRPORT. ALTITUDE CORRECTION REQUIRED AT OR BELOW -24C.","fields":[{"field":"REMARK","old":"COLD TEMPERATURE AIRPORT. ALTITUDE CORRECTION REQUIRED AT OR BELOW -25C.","new":"COLD TEMPERATURE AIRPORT. ALTITUDE CORRECTION REQUIRED AT OR BELOW -24C."}]}],"first_cycle":"2025-05-15","last_cycle":"2026-09-03"}