Date: 202102
Local time of day: 0601-1200
Location: ZZZ.Tower, US
Flight conditions: VMC
Weather elements / visibility: 15
Light: Daylight
Aircraft: Costruzioni Aeronautiche Tecnam Undifferentiated or Other Model
Operator: Personal
Operating under: Part 91
Flight plan: VFR
Mission: Personal
Flight phase: Initial Approach
Airspace: Class D ZZZ
ATC / advisory: Tower ZZZ
Aircraft component: Fuel Selector
Component problem: Improperly Operated
Reporter organization: Personal
Reporter function: Single Pilot; Captain
Reporter qualification: Flight Crew Private
Human factors: Training / Qualification; Communication Breakdown; Situational Awareness; Troubleshooting
Anomaly: Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Landing Without Clearance; Deviation / Discrepancy - Procedural Published Material / Policy; Ground Event / Encounter Fuel Issue
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Landed in Emergency Condition; Flight Crew Took Evasive Action
Contributing factors: Human Factors; Aircraft
Primary problem: Ambiguous

Narrative: On the downwind landing at ZZZ; I was #2 in the pattern when abeam the touchdown point. The plane that was #1 had just touched down; and around the same time my engine began stuttering and soon after failed. At that point; I had begun my descent and was at [approximately] 800 ft. AGL. I began to attempt to restart the engine and was unable to do so. I then decided to execute a power off 180 degree turn and land on the runway. Perhaps as a result of attempting to restart my engine and triggering the master on/off; I lost communication with ZZZ Tower (I had been previously communicating with them). The plane that was previously #1 was already quite far down the runway and not a factor. I ultimately ended up landing safely; although never received clear to land instructions from Tower due to communications failure. I attempted to advise ATC when the engine failed; however I don't believe this was communicated.Upon landing; I noticed that both of the fuel selector valves were turned off. I am not sure if these were inadvertently disabled when I was attempting to restart the engine; or perhaps I had accidentally turned both of them off before engine failure. I am skeptical that this would be the case; as I remember ensuring that they were both enabled as part of my descent checklist ~15 minutes before the engine failed. It is indeed possible that I may have turned both to the 'off' position accidentally during the descent checklist; but I do not believe the engine would have continued to operate for this long were they to be off.I do not have a clear recollection of what actions I took to restart the engine in the air as it is frankly quite a blur. After being on the ground; I enabled both fuel selector valves and attempted to restart my engine without success. I tried a second time; and it started and I taxied off the runway (at that point 2 fire trucks and a police car had arrived; and I taxied off in convoy with them).A takeaway for me is that; regardless of the cause of the engine failure; my previous flights had been in another model of airplane; and while I was very familiar with Aircraft X; I would say that I should have spent more time familiarizing myself with the emergency procedures checklist. Also; earlier in the day while pre-flighting; there were some irregularities with the communications systems in the plane; and also it was very difficult to start the engine. I did not feel that these issues were enough to warrant aborting the flight; but in hindsight perhaps I should not have flown that plane that day and had it serviced instead.




Synopsis: Private Pilot reported engine failure on downwind that resulted in a successful power-off landing.