Cessna 340/340A
Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP); Flight Crew Flight Instructor; Flight Crew Multiengine
Flight Crew Last 90 Days 25; Flight Crew Total 5000; Flight Crew Type 25
Workload; Time Pressure; Situational Awareness; Human-Machine Interface; Distraction; Confusion; Fatigue
Deviation - Altitude Overshoot; Deviation / Discrepancy - Procedural Clearance
Air Traffic Control Issued Advisory / Alert
Aircraft; Human Factors
I was returning home solo in the aircraft from recurrent flight training for the Challenger 300. I had finished up the last simulator session around XA:30 and headed to get the Cessna 340 fueled and preflighted and ready to go. I took off around XC and was in contact with Center climbing to altitude. They cleared me to maintain 8;000 feet and to expect a higher altitude shortly. I turned on the autopilot around 7;000 feet on the climb and was busy syncing the throttles and prop levers. As I was climbing ATC queried what my assigned altitude was. I checked my altimeter and noticed I had climbed through 8;000 feet and was around 8;700 feet at that point. I responded to ATC with 8;000 feet and they asked what altitude I was at. I turned off the auto pilot and had began to descend back down to 8;000 feet at that point and responded that I was coming back down to 8;000 feet. I returned to 8;000 ft and ATC didn't say anything more about it. After a few minutes they cleared me higher and I completed the flight uneventfully. Looking back; there were several contributing causes that allowed this deviation to happen. First; I had been in training all week and had just completed a simulator session and was tired mentally from that. Second; the Challenger 300 has an altitude pre-selector and altitude alert-er; while the Cessna 340 does not. Lastly; I was ready to get home after a long week at training. I could have avoided this altitude deviation by recognizing I was tired and possible stayed the night; got some sleep; and left the next morning more refreshed. However; I wanted to get home and so I took off in a hurry and tired; not the best combination. Also; being in the Challenger sim all week I was used to setting and altitude in the pre-selector and having the altitude alerter let me know I was 1;000 feet from my assigned altitude and leveling off at the pre-set altitude. In my head; since I hadn't heard any alerts from the Cessna 340 I neglected to pay attention to my altitude and blew right through it. In conclusion; trying to rely on automation that wasn't there; being mentally tired; and in a hurry to get home led to this altitude deviation.
The pilot overshot an assigned altitude due to fatigue and automation dependency.