Small aircraft on final at non tower airport has near midair collision.

Attributes
ACN	299904
Time
Date	199503
Day	Sun
Place
Locale Reference	airport : haf
State Reference	CA
Altitude	agl bound lower : 200 agl bound upper : 200
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : instructional
Make Model Name	Cessna 152
Operating Under FAR Part	Part 91
Flight Phase	descent : approach other
Flight Plan	None
Aircraft 2
Make Model Name	PA-28 Cherokee/Archer II/Dakota/Pillan/Warrior
Operating Under FAR Part	Part 91
Flight Phase	descent : approach other
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private pilot : instrument
Experience	flight time last 90 days : 13 flight time total : 315 flight time type : 80
ASRS Report	299904
Person 2
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private
Events
Anomaly	conflict : nmac
Independent Detector	other flight crewa
Resolutory Action	flight crew : took evasive action other
Consequence	Other
Miss Distance	horizontal : 100 vertical : 10
Supplementary
Primary Problem	Flight Crew Human Performance

Narrative:

Departing pao in a C-152 on a VFR flight in clear and unlimited ceiling conditions to haf. Made position calls on haf CTAF at 10 NM and 5 NM south from haf. Aircraft on CTAF reported runway 30 in use. A number of aircraft were in the pattern. I called turning the 45 for right traffic runway 30 and 1000 ft and was following a citabria (I was #3 behind the citabria when I entered downwind. The #1 aircraft, the citabria, the cherokee well behind me (he was turning crosswind when I was turning downwind from the 45), and I were all broadcasting downwind, base, final, and short final on CTAF per routine. Shortly after I called short final runway 30 and while at about 200 ft, the cherokee behind me broadcast '2 aircraft on short final half moon bay. Somebody do something!' I looked left and saw a second cherokee just behind my left wingtip about 10 ft below me, and less than 100 ft horizontal distance from me. I immediately initiated a go around with a right turn and broadcast my intentions to turn crosswind back into a right downwind for runway 30. While on final, my aircraft and the cherokee sharing short final must have been on a converging course for the runway threshold. On my second final approach, the cherokee that had called the conflict for me offered to help me strangle the other cherokee pilot who must have made either a straight-in or left approach for runway 30 and never broadcast his position or intentions and must not have been monitoring CTAF. He never initiated evasive action and I suspect never saw my aircraft and probably even today does not realize that there was ever a problem on this 'routine' approach to haf. Obviously neither the pilot in the conflicting cherokee nor I saw and avoided each other until the cherokee behind me called the conflict. I believe that I am here today because the pilot in the cherokee behind me saw the situation and broadcast the conflict on CTAF. The judgements and decisions that are questionable in this incident include: the pilot of the conflicting cherokee making a non-standard approach, his failure to monitor CTAF or broadcast his position or intentions on CTAF, and his and my failure to see and avoid.

Original NASA ASRS Text

Title: SMA ON FINAL AT NON TWR ARPT HAS NMAC.

Narrative: DEPARTING PAO IN A C-152 ON A VFR FLT IN CLR AND UNLIMITED CEILING CONDITIONS TO HAF. MADE POS CALLS ON HAF CTAF AT 10 NM AND 5 NM S FROM HAF. ACFT ON CTAF RPTED RWY 30 IN USE. A NUMBER OF ACFT WERE IN THE PATTERN. I CALLED TURNING THE 45 FOR R TFC RWY 30 AND 1000 FT AND WAS FOLLOWING A CITABRIA (I WAS #3 BEHIND THE CITABRIA WHEN I ENTERED DOWNWIND. THE #1 ACFT, THE CITABRIA, THE CHEROKEE WELL BEHIND ME (HE WAS TURNING XWIND WHEN I WAS TURNING DOWNWIND FROM THE 45), AND I WERE ALL BROADCASTING DOWNWIND, BASE, FINAL, AND SHORT FINAL ON CTAF PER ROUTINE. SHORTLY AFTER I CALLED SHORT FINAL RWY 30 AND WHILE AT ABOUT 200 FT, THE CHEROKEE BEHIND ME BROADCAST '2 ACFT ON SHORT FINAL HALF MOON BAY. SOMEBODY DO SOMETHING!' I LOOKED L AND SAW A SECOND CHEROKEE JUST BEHIND MY L WINGTIP ABOUT 10 FT BELOW ME, AND LESS THAN 100 FT HORIZ DISTANCE FROM ME. I IMMEDIATELY INITIATED A GAR WITH A R TURN AND BROADCAST MY INTENTIONS TO TURN XWIND BACK INTO A R DOWNWIND FOR RWY 30. WHILE ON FINAL, MY ACFT AND THE CHEROKEE SHARING SHORT FINAL MUST HAVE BEEN ON A CONVERGING COURSE FOR THE RWY THRESHOLD. ON MY SECOND FINAL APCH, THE CHEROKEE THAT HAD CALLED THE CONFLICT FOR ME OFFERED TO HELP ME STRANGLE THE OTHER CHEROKEE PLT WHO MUST HAVE MADE EITHER A STRAIGHT-IN OR L APCH FOR RWY 30 AND NEVER BROADCAST HIS POS OR INTENTIONS AND MUST NOT HAVE BEEN MONITORING CTAF. HE NEVER INITIATED EVASIVE ACTION AND I SUSPECT NEVER SAW MY ACFT AND PROBABLY EVEN TODAY DOES NOT REALIZE THAT THERE WAS EVER A PROB ON THIS 'ROUTINE' APCH TO HAF. OBVIOUSLY NEITHER THE PLT IN THE CONFLICTING CHEROKEE NOR I SAW AND AVOIDED EACH OTHER UNTIL THE CHEROKEE BEHIND ME CALLED THE CONFLICT. I BELIEVE THAT I AM HERE TODAY BECAUSE THE PLT IN THE CHEROKEE BEHIND ME SAW THE SIT AND BROADCAST THE CONFLICT ON CTAF. THE JUDGEMENTS AND DECISIONS THAT ARE QUESTIONABLE IN THIS INCIDENT INCLUDE: THE PLT OF THE CONFLICTING CHEROKEE MAKING A NON-STANDARD APCH, HIS FAILURE TO MONITOR CTAF OR BROADCAST HIS POS OR INTENTIONS ON CTAF, AND HIS AND MY FAILURE TO SEE AND AVOID.

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.