A twin bonanza has an near midair collision with a C172 turning final at F35, tx.

Attributes
ACN	517152
Time
Date	200107
Day	Sat
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : f35.airport
State Reference	TX
Altitude	agl single value : 700
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : ftw.tower
Operator	general aviation : personal
Make Model Name	Twin Bonanza 50
Operating Under FAR Part	Part 91
Flight Phase	descent : approach
Route In Use	approach : traffic pattern
Flight Plan	None
Aircraft 2
Operator	general aviation : personal
Make Model Name	Skyhawk 172/Cutlass 172
Operating Under FAR Part	Part 91
Flight Phase	descent : approach
Route In Use	approach : visual
Flight Plan	None
Person 1
Affiliation	other
Function	flight crew : single pilot
Qualification	pilot : commercial pilot : instrument pilot : multi engine
Experience	flight time last 90 days : 30 flight time total : 3800 flight time type : 2500
ASRS Report	517152
Person 2
Affiliation	other
Function	flight crew : single pilot
Events
Anomaly	conflict : nmac non adherence : required legal separation non adherence : published procedure non adherence : far other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : took evasive action flight crew : executed go around
Miss Distance	horizontal : 300 vertical : 200
Supplementary
Problem Areas	Flight Crew Human Performance Environmental Factor Airspace Structure Airport
Primary Problem	Flight Crew Human Performance

Narrative:

My twin bonanza aircraft entered a left downwind utilizing a 45 degree entry angle as recommended in the aim. The uncontrolled airport uses standard l-hand traffic. On approximately 1 mi final, a high wing cessna appeared at my 2 O'clock position, at about my altitude. I descended below his altitude and also banked to the left to increase the distance between the 2 aircraft. I continued my approach and landed, assuming the cessna was just sightseeing around the lake (possum kingdom), and didn't realize he was on a nonstandard right base for runway 20. After I rolled to a stop and turned around to back taxi to the taxiway, the cessna was on a close-in right base and turned to a very short final before I could exit the runway. Apparently the cessna had been giving sightseeing rides around the lake and failed to use the standard l-hand pattern.

Original NASA ASRS Text

Title: A TWIN BONANZA HAS AN NMAC WITH A C172 TURNING FINAL AT F35, TX.

Narrative: MY TWIN BONANZA ACFT ENTERED A L DOWNWIND UTILIZING A 45 DEG ENTRY ANGLE AS RECOMMENDED IN THE AIM. THE UNCTLED ARPT USES STANDARD L-HAND TFC. ON APPROX 1 MI FINAL, A HIGH WING CESSNA APPEARED AT MY 2 O'CLOCK POS, AT ABOUT MY ALT. I DSNDED BELOW HIS ALT AND ALSO BANKED TO THE L TO INCREASE THE DISTANCE BTWN THE 2 ACFT. I CONTINUED MY APCH AND LANDED, ASSUMING THE CESSNA WAS JUST SIGHTSEEING AROUND THE LAKE (POSSUM KINGDOM), AND DIDN'T REALIZE HE WAS ON A NONSTANDARD R BASE FOR RWY 20. AFTER I ROLLED TO A STOP AND TURNED AROUND TO BACK TAXI TO THE TXWY, THE CESSNA WAS ON A CLOSE-IN R BASE AND TURNED TO A VERY SHORT FINAL BEFORE I COULD EXIT THE RWY. APPARENTLY THE CESSNA HAD BEEN GIVING SIGHTSEEING RIDES AROUND THE LAKE AND FAILED TO USE THE STANDARD L-HAND PATTERN.

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.