Date: 201704
Local time of day: 1801-2400
Location: CCR.Tower, CA
Flight conditions: VMC
Light: Daylight
Aircraft: Small Aircraft; Low Wing; 1 Eng; Retractable Gear
Operator: Personal
Operating under: Part 91
Mission: Personal
Flight phase: Landing
ATC / advisory: Tower CCR
Reporter organization: Government
Reporter function: Local
Reporter qualification: Air Traffic Control Fully Certified
Human factors: Communication Breakdown; Situational Awareness; Confusion
Second reporter function: Single Pilot; Pilot Flying
Anomaly: ATC Issue All Types; Conflict Ground Conflict; Less Severe; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Landing Without Clearance; Ground Incursion Runway
Detector: Person Air Traffic Control; Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Issued New Clearance; Flight Crew FLC complied w / Automation / Advisory; Flight Crew Requested ATC Assistance / Clarification
Contributing factors: Airport; Airspace Structure; Chart Or Publication; Human Factors; Procedure
Primary problem: Human Factors

Narrative: I as the Local Controller departed aircraft X to the north off of Runway 32L. He was slightly unfamiliar with the 32 Runways; but I recognized the call sign as a fairly frequent flyer at CCR. I gave him instructions to depart; and later he called back inbound from the north with negative ATIS. I gave aircraft X the current altimeter and surface winds at CCR. He proceeded inbound with the instruction to enter a 2 mile right traffic entry for Runway 32R; and told to report a 2 mile 45.I saw aircraft X inbound 3 miles north of the field and cleared him to land number 3 to follow aircraft Z who was midfield right downwind. As aircraft X continued inbound; he entered more of a base entry when I saw him out the window again approximately a mile northeast of the field. Then aircraft X turned right downwind. Aircraft X never reported aircraft Z in sight so I updated aircraft X on the traffic to follow; which was now on short final. Aircraft X responded with 'in sight.' 3 minutes later aircraft X asked; 'Am I on the right track for the runway?' I had lost sight of aircraft X somewhere after turning base to final about a mile and a half south east of the field due to the sun and slight haze in the east area where he was. I informed him stating 'Not in sight; and the 32s point northwest bound; are you headed northwest bound?' Aircraft X immediately after I said that; then said: 'turning final now.'At this point; I also had aircraft Y on about a 1 mile final for Runway 32L who did report on final. I cleared aircraft Y to land on Runway 32L. I again cleared aircraft X to land on Runway 32R. I still did not see aircraft X; and asked him to say his altitude. He responded and I did not understand what he said. I asked him to clarify if he said 1;600 feet AGL or 300 feet AGL. Aircraft X then spoke up saying; 'I'm landing on 1L.' I immediately issued a go around to aircraft X because of 3 reasons. First I did not have control of Runway 1L as it was ground controls; second because vehicles were maneuvering on the runway and a mower was just east of the runway edge; and 3rd because aircraft Y was on very short final now for the active Runway 32L.There was no response from aircraft X. Approximately 2 seconds later; I keyed up again to say go around; but only stuttered 'go' before I noticed aircraft X was not going to comply and was just going to land on the inactive Runway 1L. I quickly issued a go around to aircraft Y; who did comply with the instruction. As aircraft X was rolling out; I asked how he heard my radio. He responded with 'loud and clear' and then proceeded to say 'I really messed up there; I'm sorry.'There wasn't any time to get control of runway 1L; even though I did attempt to get control of the runway; but Ground Control could not give me the runway because of the vehicles approved on the runway. I would recommend keeping a better eye on traffic that may be unfamiliar with our airport; even when they may seem like a frequent flyer. Because there is always training going on. I thought I did a good job asking if aircraft X was going northwest bound to be on final for the 32s; but I could clarify better on that. I also could have paid slightly more attention to the inactive runway with vehicles on it. The go around could have been issued earlier when I did not have him in sight; but expected him to be about a 1/2 mile. I should have known he wasn't lined up for 32R.


Second narrative: I landed on the wrong runway. I had taken off from Buchanan field Runway 32L. This was not the usual runway used at Buchanan. Runway 19R/1L is the runway used most of the time. The flight was quite ordinary and the return to the field was without event. I was on flight following which was discontinued as I approached Buchanan. I contacted Buchanan Tower; told them I was negative ATIS. They gave me the ATIS info and told me to make right traffic for 32R and to enter on the 45. I understood these instructions and proceeded to comply.As I entered the downwind; I was informed that I would be number 3 to land and asked if I saw the traffic. I saw one plane; making final quite low and in my mind calculated my position and turn towards that aircraft as the final leg. I did note that the plane seemed very low when making its base to final since I was at about 1;500 ft. It did not make sense visually; but I was more concerned in flying my aircraft to analyze it in more detail at that moment.As I came towards the end of what would be the downwind; I started to question whether I was understanding the layout of the runways. Buchanan has 4 runways in a set of two that are 30 degrees different from each other. It is a very confusing airport. As I made base; I had the visual of where that other plane was; and in my mind I was flying to emulate that pattern. But something did not seem right. Somewhere at that time; as I was about to turn final; I contacted the Tower and I asked them if I was on the right path towards my runway. By this time I had finished my turn to final; or close to that; but I did not get a response. I actually never heard a response.Then in a few more moments I saw that I was on final to the wrong runway; Runway 1L which is a similar length and width runway to 32R where I should have been. But at this time I was about to land; and then landed on Runway 1L. I believe I told the Tower what I did; that is landed on the wrong runway; but I didn't hear anything from them until I asked to turn at taxiway J; which they told me to do and to contact ground. I contacted ground; got clearance to taxi away; and they told me to contact them for a phone number to talk to them. After I shut down; I talked to Ground and explained what had happened.I was quite rattled by this whole incident. I could not understand what had just happened and why I had ended up on the wrong runway. Later in the day went through it with some charts; and maps and airport diagrams. What I believed happened was this. First; I am new to Buchanan.[Over the last few months]; I continued to fly with my instructor doing landings and flight instruction since I was getting my complex endorsement. All the takeoffs and landings were on Runway 1L/19R. I had a clear understanding of landmarks for this runway; the pond on the north and the hills on the south. After I got my endorsement; I sent the plane in for maintenance and some cosmetic work. The weather in those few months since has been very poor; and I did not or could not fly the plane during that time either because of maintenance or weather.That day I did fly; on returning from my flight to the north; I was flying south with the pond as my visual. As I entered the downwind the Tower told me I was number 3 and that one plane was near the numbers for the runway. I saw that plane and in my mind was positioning myself for the runway. In hindsight; where that plane was; was where I was aiming for. It still doesn't make sense to me today because it seemed to me that that plane was landing too far west and if I look at an airport diagram that would mean it was landing on 1L. But on what he landed is hindsight. At the time; I put in my mind that I was to follow him and thus aimed for that as being my final.In hindsight; I do not remember seeing the second big long runway; the one that is Runway 32R. Perhaps I was flying too close to the airport on the downwind. I remember seeing the greenbeltto the east of the airport as my downwind leg; but I see from some aerials that this may have been too close in to Runway 32R and I may have not seen Runway 32R under my right wing. But I did see the aircraft turning final off to the west; so it didn't occur to me that I was on the wrong trajectory for landing.And yet it did not feel right. At some point on the base to final; I contacted the Tower because I was afraid I was not on the right pathway. At that time; paying attention to flying was critical. I did not get a response from the Tower. I really needed to know if I was flying to the correct runway; but I also needed to make sure I flew the plane and did not have a flying mishap so close to the ground. If I had heard from the Tower that I was on the wrong trajectory; I would have expected them to tell me so; and to have me go around. On turning to final; and starting final; I still had plenty of time to put on full power and go around. But I got no such response.I was now flying final; working on getting my plane to attain the correct landing configuration and speed; making sure that my gear was down; mixture full; prop full forward. With all that checked; I was about 100-200 feet off the ground and then I saw the markings on the runway and realized I had flown to the wrong runway. At that point I felt that I had to commit to landing because I did not think I could execute a go-around. As it turned out; it was good that I did. As the plane came to a stop; I noticed that a plane on what was 32R had taken off and had crossed the intersection at about 100 feet above the ground. I had stopped maybe 1;000 feet before the intersection so I was no factor; but I wondered why the Tower had let that plane takeoff if they knew I was landing on the wrong runway. There was no guarantee that I would stop short of the intersection; that I would execute a go-around or that the other plane would fly above me if I were at the intersection.I believe the Tower advising me that I was not heading in the right direction could have corrected this error on my part easily. I believe the Tower should have responded to my request for help. But they did not. Now it's possible they did; but I did not hear it; and they also did not hold the other plane in position knowing that I was going to land on the wrong runway. Basically; they allowed the aircraft to be on the runways at the same time allowing them to maneuver in the same airspace and ground space.So in the end; everyone is safe; which is the most important; but even though I landed on the wrong runway; it could have been avoided if the Tower would have responded to my request for help at a very critical time. Hearing my request for help; and seeing that I was on the wrong runway; they should have held the other aircraft on 32R to avoid any issues with me. With their response; I would have done a go-around; evaluated the runways clearly and set up and landed on the correct runway.


Synopsis: Tower Local Controller reported not observing that an aircraft was landing on the wrong runway until it was over the landing threshold. The Controller issued go-around instructions which the pilot did not comply with.