Date: 201707
Local time of day: 0001-0600
Location: ZLC.ARTCC, UT
Flight conditions: VMC
Light: Daylight
Aircraft: SR22
Operator: Personal
Operating under: Part 91
Flight plan: IFR
Mission: Personal
Flight phase: Cruise
Airspace: Class E ZLC
ATC / advisory: Center ZLC
Reporter organization: Government
Reporter function: Enroute
Reporter qualification: Air Traffic Control Fully Certified
Human factors: Communication Breakdown; Situational Awareness
Second reporter function: Single Pilot; Pilot Flying
Anomaly: ATC Issue All Types; Deviation / Discrepancy - Procedural Other / Unknown; Inflight Event / Encounter CFTT / CFIT
Detector: Person Air Traffic Control
When detected: In-flight
Result: Air Traffic Control Issued Advisory / Alert; Air Traffic Control Issued New Clearance
Contributing factors: ATC Equipment / Nav Facility / Buildings; Aircraft
Primary problem: ATC Equipment / Nav Facility / Buildings

Narrative: Aircraft X checked on and I informed him that I would need to climb him to 12;000 in the BYI area due to the MEA. He acknowledged. When aircraft X was a few minutes away from BYI; I issued a climb to 12;000. No response. I tried again to no avail. I then proceeded to have two different aircraft on a different frequency attempt to reach aircraft X to issue the climb. The other frequency is to the west side of BOI instead of the one to the East. I thought it was possible that aircraft X was put on the west frequency.Neither aircraft were able to reach aircraft X. I continued to try and reach aircraft X on the frequency that he should have been on and then a VFR aircraft that was in the same vicinity; again to no avail. Big Sky Approach also attempted and got no response. The VFR aircraft in the same vicinity as aircraft X then gave it an attempt using Big Sky Approach's frequency and still nothing. By now; aircraft X was past BYI where the MEA jumps up to 11;400 and now clipping an MIA area of 11;300. I notified the CIC and he in turn let the next sector know. At this point; the next sector has the handoff w/ NORDO in the fourth line. Then; out of the blue aircraft X checked on and stated that a 'fellow on a different radio' called him. I issued the climb to 12;000 since there was another MIA ahead above 11;000 (11;400). It appeared that he was already climbing; as the mode C showed 11;400 or 11;500 right after I issued the climb. I then coordinated with the sector that had radar control of the aircraft.I would say I should have been more aware of what frequency the aircraft was on upon check on. And I could have always issued the climb earlier and possibly been able to reach the aircraft.


Second narrative: I was flying direct at 11;000 feet and had been transferred to Center. I had checked in with them; but was having problems hearing them since there was lots of static in the air. I assumed it was due to the cloud build up in the area. They did mention that I would need to climb to 12;000 feet further ahead. I told them I would wait to hear from them when they wanted me to climb. Further along the flight I received a call from another airplane that Center wanted me to climb to 12;000 feet and contact them.I started my climb and contacted Center. They said to climb to 12;000 feet. I acknowledged that I was climbing to 12;000 feet. When I landed the Tower said to call Center for a possible pilot deviation. I called the number and talked to a man who said he was Operations Manager. He said I had went through MEA (Minimum Enroute Altitude) of 11;000 feet to 12;000 feet. I told him I received the call from the other plane who said SLC wanted me to climb to 12;000 feet contact them which I did while I was climbing. He said it looked like I did everything I could and after the air to air I called them right away and was already climbing. He did not see it as a pilot deviation; but will pass it along. He said if someone wants to call me he has my cell number. He was puzzled why I could not hear them on their frequency. I told him as soon as I heard the air to air I called and was already in the climb. I told him there was quite a lot of static today that I thought might have something to do with the cloud buildup in the area.


Synopsis: A Center Controller reported attempting to climb an aircraft entering higher terrain; but lost radio contact with the aircraft.