Narrative:

Aircraft was in flight from hhr to oceanside airport. Over oceanside VOR at approximately 3000' MSL I was given a bearing to oceanside by LORAN of 100 degrees. I was heading 130 degrees at that time, so looked slightly to the left of the nose and saw what I thought was oceanside airport. I advised traffic in the area on unicom (123.0) of my position and made the usual reports as I entered the traffic pattern. On final approach at approximately 400' AGL I realized I was at camp pendleton airport. This was based on the numerous helicopters on the ramp. Also, the runway marking of runway 21 rather than runway 24 at oceanside also made that obvious. I applied full power and climbed out following the runway heading out of the R2503 area. When at approximately 1500' AGL I tried to contact pendleton control tower on 126.2 as listed on the sectional chart, but apparently the tower was closed as I received no reply. At no time did I observe any traffic in the vicinity of pendleton airport. I guess not much happens there on a sunday afternoon. This event could have probably have been avoided had I been more careful when visually looking for oceanside airport while being assisted with LORAN. From my position, the airports would only differ in relative bearing by 5 degrees and they are easy to confuse. Also, there are no runway markings at pendleton visible from the air as there are at oceanside. (The letters 'oceanside' painted on the runway.) that would also make in unlikely that I would have gotten as far along as final approach before realizing my mistake.

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Original NASA ASRS Text

Title: APCH TO WRONG ARPT.

Narrative: ACFT WAS IN FLT FROM HHR TO OCEANSIDE ARPT. OVER OCEANSIDE VOR AT APPROX 3000' MSL I WAS GIVEN A BEARING TO OCEANSIDE BY LORAN OF 100 DEGS. I WAS HDG 130 DEGS AT THAT TIME, SO LOOKED SLIGHTLY TO THE LEFT OF THE NOSE AND SAW WHAT I THOUGHT WAS OCEANSIDE ARPT. I ADVISED TFC IN THE AREA ON UNICOM (123.0) OF MY POS AND MADE THE USUAL RPTS AS I ENTERED THE TFC PATTERN. ON FINAL APCH AT APPROX 400' AGL I REALIZED I WAS AT CAMP PENDLETON ARPT. THIS WAS BASED ON THE NUMEROUS HELIS ON THE RAMP. ALSO, THE RWY MARKING OF RWY 21 RATHER THAN RWY 24 AT OCEANSIDE ALSO MADE THAT OBVIOUS. I APPLIED FULL PWR AND CLBED OUT FOLLOWING THE RWY HDG OUT OF THE R2503 AREA. WHEN AT APPROX 1500' AGL I TRIED TO CONTACT PENDLETON CTL TWR ON 126.2 AS LISTED ON THE SECTIONAL CHART, BUT APPARENTLY THE TWR WAS CLOSED AS I RECEIVED NO REPLY. AT NO TIME DID I OBSERVE ANY TFC IN THE VICINITY OF PENDLETON ARPT. I GUESS NOT MUCH HAPPENS THERE ON A SUNDAY AFTERNOON. THIS EVENT COULD HAVE PROBABLY HAVE BEEN AVOIDED HAD I BEEN MORE CAREFUL WHEN VISUALLY LOOKING FOR OCEANSIDE ARPT WHILE BEING ASSISTED WITH LORAN. FROM MY POS, THE ARPTS WOULD ONLY DIFFER IN RELATIVE BEARING BY 5 DEGS AND THEY ARE EASY TO CONFUSE. ALSO, THERE ARE NO RWY MARKINGS AT PENDLETON VISIBLE FROM THE AIR AS THERE ARE AT OCEANSIDE. (THE LETTERS 'OCEANSIDE' PAINTED ON THE RWY.) THAT WOULD ALSO MAKE IN UNLIKELY THAT I WOULD HAVE GOTTEN AS FAR ALONG AS FINAL APCH BEFORE REALIZING MY MISTAKE.

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.