Small Transport
Flight Crew Multiengine; Flight Crew Flight Instructor; Flight Crew Instrument
Flight Crew Last 90 Days 150; Flight Crew Total 2300; Flight Crew Type 1700
Confusion; Communication Breakdown; Situational Awareness
ATC Issue All Types; Airspace Violation All Types; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Landing Without Clearance; Deviation / Discrepancy - Procedural Clearance
Human Factors; Procedure
I was heading to Pocatello airport. 15 miles east of Pocatello I listen to ATIS and got Mike. I didn't know I had the wrong tower frequency on which was 118.5 for Idaho Falls instead of Pocatello tower 119.1. So I called up and said good morning Pocatello Tower Aircraft X. Tower replied Pocatello tower Aircraft X go ahead. I reported Aircraft X is 13 miles east of Pocatello 8500 feet we have information Mike for Runway 21. Tower replied report 5 miles left base 21. At no point here I thought something is wrong. I reported 5 miles left base 21 and was cleared to land. I landed shortly after Runway 21. No other traffic was in vicinity of airport. I called up Ground didn't reply. I later pulled up and parked at FBO and got a call in building about landing and entering Delta airspace without clearance. I was shocked and told Tower it doesn't make sense I was talking to him 13 miles out and had cleared me to land. We later realized I was talking to Idaho Falls Tower and at no point did Idaho Falls Tower realize that. First thing I told Pocatello Tower I never mentioned even once Idaho Falls and nor did Idaho Falls Tower tell me he was Idaho Falls. Secondly I reported Mike for ATIS which at that particular time Idaho Falls had different information for ATIS. Thirdly I was 13 miles east of Pocatello if indeed I was going to Idaho Falls if Tower assumed that I was about 25 miles west of Idaho Falls and the clearance would've been report left downwind 21 not left base for 21.
Small Transport pilot reported landing without a clearance from the proper controlling facility.