Wrong runway landing, non tower airport.

Attributes
ACN	114710
Time
Date	198906
Day	Sat
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : btm
State Reference	MT
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Dusk
Aircraft 1
Operator	other
Make Model Name	Small Aircraft, Low Wing, 1 Eng, Retractable Gear
Flight Phase	descent : approach landing other
Flight Plan	None
Aircraft 2
Operator	general aviation : personal
Make Model Name	Small Aircraft, High Wing, 1 Eng, Fixed Gear
Flight Phase	other
Flight Plan	None
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private
Experience	flight time last 90 days : 25 flight time total : 110 flight time type : 50
ASRS Report	114710
Person 2
Function	flight crew : single pilot
Qualification	pilot : private
Events
Anomaly	conflict : airborne less severe other anomaly other
Independent Detector	other flight crewa
Resolutory Action	none taken : detected after the fact
Consequence	Other
Miss Distance	vertical : 100
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation other

Narrative:

During approach to butte airport an airport advisory was received from FSS. Reported runway 33 was in use. One other aircraft was in the pattern and initially spotted but lost as he made turns for downwind entry. FSS asked if I could make a straight in approach to 33 which I acknowledged since I thought I was directly off the end of runway 33 but instead I later found out it was 11. I continued to let down and crossed the path of the other aircraft above by 100' and to his forward right quarter. I continued to a landing and found out it was the wrong runway. Contributing factors to this incident were pilot fatigue, unfamiliar airport (1ST time at this airport) and poor runway identifying numbers on the runway threshold. The 2 numbers on runway 11 appeared to be 2 white parallel lines right at the end of the pavement and aligned to the edges of the narrow runway, giving the appearance of a touchdown area rather than numbers. The pilot problem in addition was to not conduct a fly over of the airport above pattern altitude to determine the airport layout and make a proper entry to the pattern. Callback conversation with reporter revealed the following: reporter states he was returning from a cap search mission, having started early in the morning. Fatigue, he feels, was a major problem. He simply failed to check compass. He will never make that mistake again. Knows compass should have been used but saw what he thought, or wanted, to see at that point.

Original NASA ASRS Text

Title: WRONG RWY LNDG, NON TWR ARPT.

Narrative: DURING APCH TO BUTTE ARPT AN ARPT ADVISORY WAS RECEIVED FROM FSS. REPORTED RWY 33 WAS IN USE. ONE OTHER ACFT WAS IN THE PATTERN AND INITIALLY SPOTTED BUT LOST AS HE MADE TURNS FOR DOWNWIND ENTRY. FSS ASKED IF I COULD MAKE A STRAIGHT IN APCH TO 33 WHICH I ACKNOWLEDGED SINCE I THOUGHT I WAS DIRECTLY OFF THE END OF RWY 33 BUT INSTEAD I LATER FOUND OUT IT WAS 11. I CONTINUED TO LET DOWN AND CROSSED THE PATH OF THE OTHER ACFT ABOVE BY 100' AND TO HIS FORWARD RIGHT QUARTER. I CONTINUED TO A LNDG AND FOUND OUT IT WAS THE WRONG RWY. CONTRIBUTING FACTORS TO THIS INCIDENT WERE PLT FATIGUE, UNFAMILIAR ARPT (1ST TIME AT THIS ARPT) AND POOR RWY IDENTIFYING NUMBERS ON THE RWY THRESHOLD. THE 2 NUMBERS ON RWY 11 APPEARED TO BE 2 WHITE PARALLEL LINES RIGHT AT THE END OF THE PAVEMENT AND ALIGNED TO THE EDGES OF THE NARROW RWY, GIVING THE APPEARANCE OF A TOUCHDOWN AREA RATHER THAN NUMBERS. THE PLT PROBLEM IN ADDITION WAS TO NOT CONDUCT A FLY OVER OF THE ARPT ABOVE PATTERN ALT TO DETERMINE THE ARPT LAYOUT AND MAKE A PROPER ENTRY TO THE PATTERN. CALLBACK CONVERSATION WITH REPORTER REVEALED THE FOLLOWING: REPORTER STATES HE WAS RETURNING FROM A CAP SEARCH MISSION, HAVING STARTED EARLY IN THE MORNING. FATIGUE, HE FEELS, WAS A MAJOR PROBLEM. HE SIMPLY FAILED TO CHECK COMPASS. HE WILL NEVER MAKE THAT MISTAKE AGAIN. KNOWS COMPASS SHOULD HAVE BEEN USED BUT SAW WHAT HE THOUGHT, OR WANTED, TO SEE AT THAT POINT.

Data retrieved from NASA's ASRS site as of August 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.