Narrative:

I was returning from sacramento on a cross country flight going back to long beach. The WX had been fine all throughout the trip. It was then about XA00 and getting dusky when I was close to van nuys. The socal approach controller told me to stay west of the vny airport, which I had stayed well clear of it. I was getting flight following throughout the entire trip. A few mins later, the controller told me to squawk VFR and that radar services were terminated. I was then right over a mountain range cruising at 3500 ft, homing in to smo VOR. I was going to take the smo 312 degree radial special flight rules area to pass through the lax corridor, which I had done numerous times before. Upon reaching the mountain pass, I saw a marine layer covering the ground and water as far as I could see. I was trying to track the smo 312 degree radial and then a large jet was approaching my way to land at vny airport. I turned and made a quick descent to get out of its path. After it had passed, I turned and climbed back up to 3500 ft to continue tracking the smo 312 degree radial. Then, I found myself off course and couldn't see anything below me. I had no idea if I was over land or water. I saw a few other planes flying in the vicinity of lax. Due to the marine layer, I couldn't see lax, but I knew it was several mi away. I thought it would be the best idea to contact socal again and get a clearance through the class B airspace, and also make an ILS approach into lgb. Since I couldn't see what was below me for ground reference, I wasn't sure if I was already in class B airspace or not. I didn't think that I was. After contacting socal, I was cleared through the area and radar vectored to lgb. I was flying a no-gyro approach as the airplane's vacuum system went out during flight. I had to rely heavily on the magnetic compass for navigation. I thought I did what was feasible and necessary under the conditions I was under. It was then on the downwind leg of the approach that I was instructed by socal to call a socal supervisor regarding entrance into class B airspace. Within 30 mins of landing, I called the socal supervisor and gave him my information and explained what had happened. He said that I was in class B airspace right over the marker beacons of lax and that it was in about the worse area to be in. I can't confirm that, as I couldn't see anything down below. That was the reason why I contacted socal initially. He then said I'll be contacted by FSDO in a couple of weeks. All I can do now is wait.

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Original NASA ASRS Text

Title: INST RATED PVT PLT BECAME DISORIENTED DURING A XCOUNTRY FLT WHEN FLYING OVER AN UNDERCAST AS IT BECAME DARK. AFTER CONTACTING APCH CTL, ATC PROVIDED A FLT ASSIST AND GAVE HIM NO GYRO VECTORS TO DEST SINCE HIS VACUUM SYS HAD FAILED. HE ALSO LEARNED THAT HE HAD ENTERED CLASS B AIRSPACE OVER THE LAX MARKER BEACONS.

Narrative: I WAS RETURNING FROM SACRAMENTO ON A XCOUNTRY FLT GOING BACK TO LONG BEACH. THE WX HAD BEEN FINE ALL THROUGHOUT THE TRIP. IT WAS THEN ABOUT XA00 AND GETTING DUSKY WHEN I WAS CLOSE TO VAN NUYS. THE SOCAL APCH CTLR TOLD ME TO STAY W OF THE VNY ARPT, WHICH I HAD STAYED WELL CLR OF IT. I WAS GETTING FLT FOLLOWING THROUGHOUT THE ENTIRE TRIP. A FEW MINS LATER, THE CTLR TOLD ME TO SQUAWK VFR AND THAT RADAR SVCS WERE TERMINATED. I WAS THEN RIGHT OVER A MOUNTAIN RANGE CRUISING AT 3500 FT, HOMING IN TO SMO VOR. I WAS GOING TO TAKE THE SMO 312 DEG RADIAL SPECIAL FLT RULES AREA TO PASS THROUGH THE LAX CORRIDOR, WHICH I HAD DONE NUMEROUS TIMES BEFORE. UPON REACHING THE MOUNTAIN PASS, I SAW A MARINE LAYER COVERING THE GND AND WATER AS FAR AS I COULD SEE. I WAS TRYING TO TRACK THE SMO 312 DEG RADIAL AND THEN A LARGE JET WAS APCHING MY WAY TO LAND AT VNY ARPT. I TURNED AND MADE A QUICK DSCNT TO GET OUT OF ITS PATH. AFTER IT HAD PASSED, I TURNED AND CLBED BACK UP TO 3500 FT TO CONTINUE TRACKING THE SMO 312 DEG RADIAL. THEN, I FOUND MYSELF OFF COURSE AND COULDN'T SEE ANYTHING BELOW ME. I HAD NO IDEA IF I WAS OVER LAND OR WATER. I SAW A FEW OTHER PLANES FLYING IN THE VICINITY OF LAX. DUE TO THE MARINE LAYER, I COULDN'T SEE LAX, BUT I KNEW IT WAS SEVERAL MI AWAY. I THOUGHT IT WOULD BE THE BEST IDEA TO CONTACT SOCAL AGAIN AND GET A CLRNC THROUGH THE CLASS B AIRSPACE, AND ALSO MAKE AN ILS APCH INTO LGB. SINCE I COULDN'T SEE WHAT WAS BELOW ME FOR GND REF, I WASN'T SURE IF I WAS ALREADY IN CLASS B AIRSPACE OR NOT. I DIDN'T THINK THAT I WAS. AFTER CONTACTING SOCAL, I WAS CLRED THROUGH THE AREA AND RADAR VECTORED TO LGB. I WAS FLYING A NO-GYRO APCH AS THE AIRPLANE'S VACUUM SYS WENT OUT DURING FLT. I HAD TO RELY HEAVILY ON THE MAGNETIC COMPASS FOR NAV. I THOUGHT I DID WHAT WAS FEASIBLE AND NECESSARY UNDER THE CONDITIONS I WAS UNDER. IT WAS THEN ON THE DOWNWIND LEG OF THE APCH THAT I WAS INSTRUCTED BY SOCAL TO CALL A SOCAL SUPVR REGARDING ENTRANCE INTO CLASS B AIRSPACE. WITHIN 30 MINS OF LNDG, I CALLED THE SOCAL SUPVR AND GAVE HIM MY INFO AND EXPLAINED WHAT HAD HAPPENED. HE SAID THAT I WAS IN CLASS B AIRSPACE RIGHT OVER THE MARKER BEACONS OF LAX AND THAT IT WAS IN ABOUT THE WORSE AREA TO BE IN. I CAN'T CONFIRM THAT, AS I COULDN'T SEE ANYTHING DOWN BELOW. THAT WAS THE REASON WHY I CONTACTED SOCAL INITIALLY. HE THEN SAID I'LL BE CONTACTED BY FSDO IN A COUPLE OF WKS. ALL I CAN DO NOW IS WAIT.

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.