Narrative:

I was the flight instructor (right seat) in a PA23-150 during a VFR multi-engine training flight. We approached kalaeloa airport from the northeast at 1000 ft, 110 KTS. After contacting the tower, we received instructions to enter a left downwind for runway 4L. No other traffic information was given, however, it was apparent 2-3 other aircraft were operating in the traffic pattern for runway 4L&right. The student descended to 800 ft MSL and slowed to 100 KTS. The controller was having difficulty determining the call signs and position of 2 aircraft with similar sounding call signs. As our aircraft entered the left downwind, the controller said 'north-number, aircraft Y, your traffic is turning left downwind abeam the departure end of runway 4L.' I realized that was our exact location. I searched to our 10-11 O'clock position, unable to find the traffic. As I turned to my 8-9 O'clock position, I saw a C150 slightly below and heading directly toward my left wing. I didn't even have time to acknowledge the controller, but I took the airplane, banked 60 degrees, added full power and turned directly downwind. I averted the collision, however, the aircraft was not more than 200 ft horizontal and not less than 25 ft vertical from my position. I continued flying the downwind, reported turning base, and noticed the C150 started to turn its base (until the pilot noticed us on base). The C150 then continued on the downwind. After I reported base, the controller asked who reported base. Clearly the (air nat guard) controller was overwhelmed with the 4 aircraft operating on 2 runways. After our landing, we departed uneventfully.

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Original NASA ASRS Text

Title: PIPER INSTRUCTOR PLT HAS NMAC WITH C150 DURING PATTERN ENTRY AT A CTLED ARPT.

Narrative: I WAS THE FLT INSTRUCTOR (R SEAT) IN A PA23-150 DURING A VFR MULTI-ENG TRAINING FLT. WE APCHED KALAELOA ARPT FROM THE NE AT 1000 FT, 110 KTS. AFTER CONTACTING THE TWR, WE RECEIVED INSTRUCTIONS TO ENTER A L DOWNWIND FOR RWY 4L. NO OTHER TFC INFO WAS GIVEN, HOWEVER, IT WAS APPARENT 2-3 OTHER ACFT WERE OPERATING IN THE TFC PATTERN FOR RWY 4L&R. THE STUDENT DSNDED TO 800 FT MSL AND SLOWED TO 100 KTS. THE CTLR WAS HAVING DIFFICULTY DETERMINING THE CALL SIGNS AND POS OF 2 ACFT WITH SIMILAR SOUNDING CALL SIGNS. AS OUR ACFT ENTERED THE L DOWNWIND, THE CTLR SAID 'N-NUMBER, ACFT Y, YOUR TFC IS TURNING L DOWNWIND ABEAM THE DEP END OF RWY 4L.' I REALIZED THAT WAS OUR EXACT LOCATION. I SEARCHED TO OUR 10-11 O'CLOCK POS, UNABLE TO FIND THE TFC. AS I TURNED TO MY 8-9 O'CLOCK POS, I SAW A C150 SLIGHTLY BELOW AND HDG DIRECTLY TOWARD MY L WING. I DIDN'T EVEN HAVE TIME TO ACKNOWLEDGE THE CTLR, BUT I TOOK THE AIRPLANE, BANKED 60 DEGS, ADDED FULL PWR AND TURNED DIRECTLY DOWNWIND. I AVERTED THE COLLISION, HOWEVER, THE ACFT WAS NOT MORE THAN 200 FT HORIZ AND NOT LESS THAN 25 FT VERT FROM MY POS. I CONTINUED FLYING THE DOWNWIND, RPTED TURNING BASE, AND NOTICED THE C150 STARTED TO TURN ITS BASE (UNTIL THE PLT NOTICED US ON BASE). THE C150 THEN CONTINUED ON THE DOWNWIND. AFTER I RPTED BASE, THE CTLR ASKED WHO RPTED BASE. CLRLY THE (AIR NAT GUARD) CTLR WAS OVERWHELMED WITH THE 4 ACFT OPERATING ON 2 RWYS. AFTER OUR LNDG, WE DEPARTED UNEVENTFULLY.

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.