Narrative:

I, a student airplane pilot, received a WX briefing and filed a VFR (round robin) cross country flight plan in a PA28161 on the morning of mar/xx/94. I departed long beach airport at XA22 am. Route of flight lgb-sli-ocn-OCNR110-L39 and return. After departing ramona, I tuned in palomar airport (crq) ATIS, which stated 3600 overcast, 1500 scattered, visibility 5, fog since the conditions seemed to be deteriorating. The aircraft experienced engine roughness a couple of mi northeast of oceanside airport. I began immediately descending while adjusting the mixture. Monitoring oceanside unicom, I obtained information that runway 21 was favored. Fearing that the engine would quit, I decided that it was in my best interest to make a precautionary landing. I didn't, 'declare an emergency' since oceanside airport (L32) has a unicom frequency, not an air traffic controling agency. I chose the nearest airport because I felt that I was unable to comply with far 91.155(a) VFR cloud criteria. I began reviewing the emergency checklist for engine roughness in-flight. The problem did not go away. I announced my position midfield entering right downwind, completing the landing checklist for runway 21. Upon landing I realized I had made a mistake. I actually landed at a military air base. Camp pendleton (nfg) in restr area, R2503. I discussed my situation with a captain at camp pendleton. The captain stated that I had taken the correct evasive course of action. He also stated, that the airports are 4 1/2 mi apart and explained that mistaking airports was a common situation with camp pendleton and oceanside airport. Both airports use the same runway numbers, 21, which have resulted in confusing other pilots in the past. The captain was very understanding, however, I do not think that he looked forward to the necessary paperwork involved. As PIC, I had felt it was necessary to take the actions that I took in order to prevent possible loss of life and property.

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Original NASA ASRS Text

Title: UNAUTH PENETRATION OF AIRSPACE RESTR AREA AND WRONG ARPT LNDG. DIVERSION TO ALTERNATE.

Narrative: I, A STUDENT AIRPLANE PLT, RECEIVED A WX BRIEFING AND FILED A VFR (ROUND ROBIN) XCOUNTRY FLT PLAN IN A PA28161 ON THE MORNING OF MAR/XX/94. I DEPARTED LONG BEACH ARPT AT XA22 AM. RTE OF FLT LGB-SLI-OCN-OCNR110-L39 AND RETURN. AFTER DEPARTING RAMONA, I TUNED IN PALOMAR ARPT (CRQ) ATIS, WHICH STATED 3600 OVCST, 1500 SCATTERED, VISIBILITY 5, FOG SINCE THE CONDITIONS SEEMED TO BE DETERIORATING. THE ACFT EXPERIENCED ENG ROUGHNESS A COUPLE OF MI NE OF OCEANSIDE ARPT. I BEGAN IMMEDIATELY DSNDING WHILE ADJUSTING THE MIXTURE. MONITORING OCEANSIDE UNICOM, I OBTAINED INFO THAT RWY 21 WAS FAVORED. FEARING THAT THE ENG WOULD QUIT, I DECIDED THAT IT WAS IN MY BEST INTEREST TO MAKE A PRECAUTIONARY LNDG. I DIDN'T, 'DECLARE AN EMER' SINCE OCEANSIDE ARPT (L32) HAS A UNICOM FREQ, NOT AN AIR TFC CTLING AGENCY. I CHOSE THE NEAREST ARPT BECAUSE I FELT THAT I WAS UNABLE TO COMPLY WITH FAR 91.155(A) VFR CLOUD CRITERIA. I BEGAN REVIEWING THE EMER CHKLIST FOR ENG ROUGHNESS INFLT. THE PROB DID NOT GO AWAY. I ANNOUNCED MY POS MIDFIELD ENTERING R DOWNWIND, COMPLETING THE LNDG CHKLIST FOR RWY 21. UPON LNDG I REALIZED I HAD MADE A MISTAKE. I ACTUALLY LANDED AT A MIL AIR BASE. CAMP PENDLETON (NFG) IN RESTR AREA, R2503. I DISCUSSED MY SIT WITH A CAPT AT CAMP PENDLETON. THE CAPT STATED THAT I HAD TAKEN THE CORRECT EVASIVE COURSE OF ACTION. HE ALSO STATED, THAT THE ARPTS ARE 4 1/2 MI APART AND EXPLAINED THAT MISTAKING ARPTS WAS A COMMON SIT WITH CAMP PENDLETON AND OCEANSIDE ARPT. BOTH ARPTS USE THE SAME RWY NUMBERS, 21, WHICH HAVE RESULTED IN CONFUSING OTHER PLTS IN THE PAST. THE CAPT WAS VERY UNDERSTANDING, HOWEVER, I DO NOT THINK THAT HE LOOKED FORWARD TO THE NECESSARY PAPERWORK INVOLVED. AS PIC, I HAD FELT IT WAS NECESSARY TO TAKE THE ACTIONS THAT I TOOK IN ORDER TO PREVENT POSSIBLE LOSS OF LIFE AND PROPERTY.

Data retrieved from NASA's ASRS site as of July 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.