Date: 201308
Local time of day: 1801-2400
Location: ZZZ.Airport, US
Flight conditions: VMC
Weather elements / visibility: 10
Light: Night
Aircraft: Diamond Aircraft Undifferentiated or Other Model
Operator: Air Taxi
Operating under: Part 135
Flight plan: IFR
Mission: Passenger
Flight phase: Final Approach
Airspace: Class C ZZZ
ATC / advisory: Tower ZZZ
Reporter organization: Air Taxi
Reporter function: Pilot Flying; First Officer
Reporter qualification: Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Flight Instructor; Flight Crew Commercial
Human factors: Fatigue
Second reporter function: Captain; Pilot Not Flying
Anomaly: Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance
Detector: Person Flight Crew; Person Air Traffic Control
When detected: In-flight
Result: Air Traffic Control Issued New Clearance; Flight Crew Became Reoriented
Contributing factors: Aircraft; Human Factors
Primary problem: Human Factors

Narrative: On an empty leg to pick up a medical team and patient late at night; I inadvertently landed on the wrong runway. I was pilot flying at the time; and when we heard enroute from Approach Control the runway in use; I thought I heard 17R. So from then on I was fixated on the right side. The Captain (pilot not flying); did not hear 17R; but correctly heard 17L; so started setting up for that runway; backing up the instruments to track the localizer and glideslope; even though it would be a visual approach. We both were tired; and felt rushed as usual; so the Captain did the approach briefing instead of me. As we got within approximately 10 NM of the airport we saw the beacon; and called the airport in sight. The Controller then cleared us for the visual to 17L; but I again thought I heard 17 Right. I continued descending for the right side; and even though I noticed that the glideslope and localizer were acting funny; I was too tired to register what the issue was. The Captain was also exhausted; having been up all day long as well; so when I mentioned the issue; he agreed that something was strange with the instruments; but was not able to figure it out. Since our aircraft has a history of Instrument issues; we didn't worry about it further. As I continued towards the runway; we switched to Tower; who cleared us to land on 17L. I again did not notice the Left; and still continued lining up for 17R. When I was within 2 NM of the threshold to 17R; the Controller apparently realized our error and quickly cleared us to land on 17R. We read back the clearance; and that is when it dawned on the Captain and I that something was wrong. I continued and landed without incident; and taxied to the FBO; without further mention of an issue from the Tower or Ground Control. Luckily there was no other traffic in the area; both on the ground and in the air. Obviously this situation could have been much worse; we were simply lucky that our fatigue did not cause a worse issue. This is the first major issue I have experienced; and consider it to be because of the inherent fatigue that is caused from a 24 hour on call schedule of the air ambulance industry. I have lost track of the number of times I have been fatigued; but have chosen to fly anyways because I am locked into an extremely punitive monetary contract with my air ambulance company. I was told by my Chief Pilot that if I called in fatigued; it would be ok once; but more than that; and I would be looking for another job. I cannot afford the monetary hit I would take if I quit; but I am way past my personal line of safety. Being called out at 9-10 pm for an all-nighter and flying until 10-11 am (after having been up all day) causes instant fatigue. This type of schedule must not be allowed to continue before something much worse happens.


Second narrative: Having the airport in sight the Approach Controller had cleared us for a visual approach to 17L. I had programmed the ILS 17L into the box and we had discussed the approach setup with the Copilot who was flying. In this aircraft you can't set up the captains side for the approach until you are on vector headings or it confuses the navigation/autopilot system. So after going to vectors; you must dial in the frequency; course heading and make some changes in the GPS to activate the approach. I had been heads down doing this and as I looked up the Copilot was rolling out on final. We were both wondering why we were getting erroneous errors from the glide slope and the localizer was to the left. About the time this all made sense; the Tower Controller told us we were cleared to land on 17R. We landed and in the discussion later; the Copilot told me he knew he was landing on 17R; that's what he thought we had been cleared for; yet I remember going over and restating; ILS set for 17L; and cleared for 17L. There was no other traffic in the area; so it posed no conflict with other traffic. The airport runway lighting was almost invisible; until you were lined up with them; making it more difficult to see the entire airport. I attribute this primarily on my part to fatigue. I was very tired; as we often are on this job. The flight crews are typically scheduled on call for 24 hrs for 5 days straight; (or more) and you never know when you can rest. You could be up all day; and when you are going to be get called for a 14 hour trip. It's not unusual to be up for 25 to 30 hours getting back from a trip.


Synopsis: Air Ambulance crew reports being cleared for the visual approach to Runway 17L but the flying First Officer believes that 17R is the clearance and continues to believe so until short final when the Tower changes the clearance to 17R. Extreme fatigue was cited as a factor by both pilots.