Narrative:

Flying a practice NDB approach to runway 30 at lgb in VFR conditions. Tower cleared me to land runway 30, and I requested a low approach. Tower responded, I believe, start missed approach at or south of blue pyramid. Even though I read back the clearance, I interpreted it to mean at or after the blue pyramid. Flying the approach, I descended from 1600 ft MSL to 800 ft MSL (MDA 680 ft MSL). After passing the blue pyramid, I continued toward runway 30 and attempted to advise the tower I was executing the missed approach. My recollection is that there was considerable frequency congestion, and it was several seconds before I was able to contact the tower. I had begun a gradual climb, and by the time I advised the tower I was on the miss, my altitude was probably 1000-1100 ft MSL and I was in a left turn to 200 degrees. I glimpsed an aircraft (low wing, single engine) pass beneath me approximately 300 ft below my altitude. I was not aware of any evasive action taken. The tower handed me off to socal approach and they advised me to call lgb tower back concerning my missed approach. I did so, explained my actions, and they handed me back to socal approach. I subsequently flew another NDB approach to lgb with a miss, and returned to torrance. I was unaware of any evasive action taken.

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Original NASA ASRS Text

Title: PLT MISUNDERSTANDS AN LGB TWR INSTRUCTION TO MAKE A L TURNOUT AT A WELL KNOWN LANDMARK AT APPROX ONE HALF MI FROM RWY.

Narrative: FLYING A PRACTICE NDB APCH TO RWY 30 AT LGB IN VFR CONDITIONS. TWR CLRED ME TO LAND RWY 30, AND I REQUESTED A LOW APCH. TWR RESPONDED, I BELIEVE, START MISSED APCH AT OR S OF BLUE PYRAMID. EVEN THOUGH I READ BACK THE CLRNC, I INTERPED IT TO MEAN AT OR AFTER THE BLUE PYRAMID. FLYING THE APCH, I DSNDED FROM 1600 FT MSL TO 800 FT MSL (MDA 680 FT MSL). AFTER PASSING THE BLUE PYRAMID, I CONTINUED TOWARD RWY 30 AND ATTEMPTED TO ADVISE THE TWR I WAS EXECUTING THE MISSED APCH. MY RECOLLECTION IS THAT THERE WAS CONSIDERABLE FREQ CONGESTION, AND IT WAS SEVERAL SECONDS BEFORE I WAS ABLE TO CONTACT THE TWR. I HAD BEGUN A GRADUAL CLB, AND BY THE TIME I ADVISED THE TWR I WAS ON THE MISS, MY ALT WAS PROBABLY 1000-1100 FT MSL AND I WAS IN A L TURN TO 200 DEGS. I GLIMPSED AN ACFT (LOW WING, SINGLE ENG) PASS BENEATH ME APPROX 300 FT BELOW MY ALT. I WAS NOT AWARE OF ANY EVASIVE ACTION TAKEN. THE TWR HANDED ME OFF TO SOCAL APCH AND THEY ADVISED ME TO CALL LGB TWR BACK CONCERNING MY MISSED APCH. I DID SO, EXPLAINED MY ACTIONS, AND THEY HANDED ME BACK TO SOCAL APCH. I SUBSEQUENTLY FLEW ANOTHER NDB APCH TO LGB WITH A MISS, AND RETURNED TO TORRANCE. I WAS UNAWARE OF ANY EVASIVE ACTION TAKEN.

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.