C172 reporter has near midair collision with an small aircraft on short final approach.

Attributes
ACN	316956
Time
Date	199509
Day	Sat
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : ccr
State Reference	CA
Altitude	msl bound lower : 400 msl bound upper : 400
Environment
Flight Conditions	VMC
Light	Dusk
Aircraft 1
Controlling Facilities	tower : ccr
Operator	general aviation : personal
Make Model Name	Skyhawk 172/Cutlass 172
Operating Under FAR Part	Part 91
Flight Phase	landing other
Flight Plan	None
Aircraft 2
Operator	general aviation : personal
Make Model Name	PA-28 Cherokee/Archer II/Dakota/Pillan/Warrior
Operating Under FAR Part	Part 91
Flight Phase	landing other
Flight Plan	None
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : cfi pilot : commercial pilot : instrument
Experience	flight time last 90 days : 120 flight time total : 9000 flight time type : 60
ASRS Report	316956
Person 2
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private
Events
Anomaly	conflict : nmac non adherence : far other anomaly other
Independent Detector	other flight crewa
Resolutory Action	controller : issued new clearance flight crew : took evasive action
Consequence	Other
Miss Distance	horizontal : 150 vertical : 0
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

I was nearing the end of a VFR flight from lincoln airport, ca, at 2500 ft MSL when I was changed from travis approach control to concord tower frequency 119.7. I reported to concord tower 2 mi north of port chicago (6-7 mi form ccr) with information 'tango.' I was cleared to enter right traffic for runway 32R and was told that there was a cessna on an instrument approach to runway 19 to circle left for landing on runway 32R and there was also another cessna on an instrument approach behind me and was still talking to travis approach. I reported the cessna behind me was in sight. There were several aircraft in the pattern and I was watching for them as I descended to 1000 ft MSL. I entered the right downwind at mid field for runway 32R and called 'downwind' and was told by the tower controller that I was #4 to land with 2 cherokees in front of me and the one I was following was turning base near mt diablo hospital. I proceeded downwind and tower cleared me to land behind the cherokee that was turning final. I looked and there was a light colored, low wing aircraft rolling out on final. I took that to be the aircraft I was to follow and I began a descending turn to base near the high rise buildings in downtown concord. As I entered base, there was 1 low wing aircraft touching down and 1 low wing aircraft on short final and a cessna taxiing off runway 32R. I assumed these were the 3 aircraft in front of me. While on base I cleared final and did not see any aircraft. I turned onto final and as I was about to roll out, I noticed that I was a little high on the VASI so I held in a slight slip at which time I noticed a red and white cherokee on my left, at the same altitude, and converging. I then started an immediate turn to the right and added power to stop my descent and start a climb. At about this time the tower controller told the cherokee to go around and/or me to continue in my right turn for a 360 degree turn and return for landing. A different controller cleared me to land, as I found out later they were in the midst of changing position in the tower.

Original NASA ASRS Text

Title: C172 RPTR HAS NMAC WITH AN SMA ON SHORT FINAL APCH.

Narrative: I WAS NEARING THE END OF A VFR FLT FROM LINCOLN ARPT, CA, AT 2500 FT MSL WHEN I WAS CHANGED FROM TRAVIS APCH CTL TO CONCORD TWR FREQ 119.7. I RPTED TO CONCORD TWR 2 MI N OF PORT CHICAGO (6-7 MI FORM CCR) WITH INFO 'TANGO.' I WAS CLRED TO ENTER R TFC FOR RWY 32R AND WAS TOLD THAT THERE WAS A CESSNA ON AN INSTRUMENT APCH TO RWY 19 TO CIRCLE L FOR LNDG ON RWY 32R AND THERE WAS ALSO ANOTHER CESSNA ON AN INSTRUMENT APCH BEHIND ME AND WAS STILL TALKING TO TRAVIS APCH. I RPTED THE CESSNA BEHIND ME WAS IN SIGHT. THERE WERE SEVERAL ACFT IN THE PATTERN AND I WAS WATCHING FOR THEM AS I DSNDED TO 1000 FT MSL. I ENTERED THE R DOWNWIND AT MID FIELD FOR RWY 32R AND CALLED 'DOWNWIND' AND WAS TOLD BY THE TWR CTLR THAT I WAS #4 TO LAND WITH 2 CHEROKEES IN FRONT OF ME AND THE ONE I WAS FOLLOWING WAS TURNING BASE NEAR MT DIABLO HOSPITAL. I PROCEEDED DOWNWIND AND TWR CLRED ME TO LAND BEHIND THE CHEROKEE THAT WAS TURNING FINAL. I LOOKED AND THERE WAS A LIGHT COLORED, LOW WING ACFT ROLLING OUT ON FINAL. I TOOK THAT TO BE THE ACFT I WAS TO FOLLOW AND I BEGAN A DSNDING TURN TO BASE NEAR THE HIGH RISE BUILDINGS IN DOWNTOWN CONCORD. AS I ENTERED BASE, THERE WAS 1 LOW WING ACFT TOUCHING DOWN AND 1 LOW WING ACFT ON SHORT FINAL AND A CESSNA TAXIING OFF RWY 32R. I ASSUMED THESE WERE THE 3 ACFT IN FRONT OF ME. WHILE ON BASE I CLRED FINAL AND DID NOT SEE ANY ACFT. I TURNED ONTO FINAL AND AS I WAS ABOUT TO ROLL OUT, I NOTICED THAT I WAS A LITTLE HIGH ON THE VASI SO I HELD IN A SLIGHT SLIP AT WHICH TIME I NOTICED A RED AND WHITE CHEROKEE ON MY LEFT, AT THE SAME ALT, AND CONVERGING. I THEN STARTED AN IMMEDIATE TURN TO THE R AND ADDED PWR TO STOP MY DSCNT AND START A CLB. AT ABOUT THIS TIME THE TWR CTLR TOLD THE CHEROKEE TO GAR AND/OR ME TO CONTINUE IN MY R TURN FOR A 360 DEG TURN AND RETURN FOR LNDG. A DIFFERENT CTLR CLRED ME TO LAND, AS I FOUND OUT LATER THEY WERE IN THE MIDST OF CHANGING POS IN THE TWR.

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.