Date: 201603
Local time of day: 0601-1200
Location: A80.TRACON, GA
Flight conditions: IMC
Weather elements / visibility: Turbulence
Light: Daylight
Aircraft: Small Transport
Operator: Personal
Operating under: Part 91
Flight plan: IFR
Mission: Personal
Flight phase: Cruise
Airspace: Class E A80
ATC / advisory: TRACON A80
Reporter organization: Personal
Reporter function: Single Pilot; Pilot Flying
Reporter qualification: Flight Crew Private; Flight Crew Multiengine; Flight Crew Instrument
Human factors: Distraction; Workload; Communication Breakdown; Confusion
Anomaly: ATC Issue All Types; Aircraft Equipment Problem Less Severe; Deviation - Altitude Excursion From Assigned Altitude; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Inflight Event / Encounter Weather / Turbulence
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Returned To Clearance
Contributing factors: Weather
Primary problem: Weather

Narrative: The flight was to BGF. Cleared as filed ..AYS VNA LGC. Filed 9000 ft. Given 8;000 feet. Flight plan was intended to avoid MOA's. ZJX center tried to be helpful before AYS and offered direct. From past experience of multiple reroutes near Moody MOA and Atlanta Class B; I declined initial offer; but was offered direct LGC and took that. Then flew into an area where Jacksonville Center radar was down. New route clearance given using airways and VORs with reporting points. At 8;000 feet I was on top of clouds. In the approximate vicinity of PECAN; was told to descend to 6;000 feet. That put us into the tops of frontal clouds and we began to experience moderate turbulence. I slowed to turbulence speed and I requested from Jacksonville a return to 8;000 feet to get out of the tops. I was not clear on why they had brought us down. Jacksonville Center told me to contact Atlanta with request. I tried repeatedly to get a hold of Atlanta; I could hear them; but they could not hear us. At the same time the turbulence went from moderate to occasional severe. Passengers were distressed and I was trying to focus on getting through to Atlanta to at least get a block altitude. Another aircraft heard me trying to reach Atlanta and relayed. I could hear the Atlanta controller say; 'I don't know who that is; I don't have them'. Then came back with a relay to give us [a different frequency]. All this happened over about 3-5 minutes. As I got Atlanta [with the new frequency] on the radio; I observed that the autopilot had disconnected in the turbulence and I was off both course and altitude. I was about 1;000 feet high; but still IMC and in turbulence. Seeing that; I asked the controller if I could get to 8;000 again. He denied request in a very angry voice because of traffic between us and LGC and yelled at me about the altitude deviation. I told him I would get it back down-explained that turbulence was knocking us around and I asked to try 4;000. He cleared us to 4;000 and that did not help much. Asked again for higher and if possible 8;000. He was really annoyed 'because not enough time to LGC'. Finally; he asked me what approach we wanted at LGC. I informed him that our destination was BGF-Winchester TN. He said he only had us cleared to LGC! I had to repeat that our clearance was to BGF. But with the correct destination; he was able to clear us back up on top and direct to BGF.Contributing factors to the altitude deviation; ATC lost the flight plan; Center radar was down; ATC had me descend into turbulence because they had the wrong destination; ATC gave the wrong frequency for handoff; I was distracted by being unable to reach ATC and knowing I was in a no radar environment as well as by my distressed passengers in bad turbulence. Also contributing was that I had never seen the autopilot disengage in the 15 years I have flown this aircraft. Not sure if I banged the disconnect button in the bumps or it did it automatically and I will investigate with the technician. Once I realized it and was back in touch with ATC; I hand flew the aircraft until we were again on top and enroute. I did not argue with the controller when he was yelling about the altitude deviation because everyone was upset already. I don't know exactly how they lost my flight plan; but I am guessing that the helpful controller at ZJX center from earlier in the flight who tried to clear me direct was the start of the chain. However; at the end of the day; it was my responsibility to monitor the course and altitude even with all the other contributing factors and not to trust the autopilot as much as I did.




Synopsis: BE-55 pilot reported that their autopilot disconnected inadvertently in turbulence which resulted in an altitude and course deviation. Contributing factors included Center radar down; ATC confusion on destination flight plan; a frequency change; and moderate to occasionally severe turbulence which created distressed passengers.