Near midair collision in traffic pattern.

Attributes
ACN	106998
Time
Date	198903
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : 1pa6
State Reference	PA
Altitude	msl bound lower : 1500 msl bound upper : 1500
Environment
Flight Conditions	VMC
Light	Dusk
Aircraft 1
Operator	general aviation : instructional
Make Model Name	Small Aircraft, Low Wing, 1 Eng, Fixed Gear
Flight Phase	descent : approach other
Flight Plan	None
Aircraft 2
Operator	general aviation : personal
Make Model Name	Small Aircraft, Low Wing, 1 Eng, Fixed Gear
Flight Phase	descent : approach other
Flight Plan	None
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : cfi pilot : atp
Experience	flight time last 90 days : 100 flight time total : 10000
ASRS Report	106998
Person 2
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	conflict : nmac other spatial deviation
Independent Detector	other flight crewa
Resolutory Action	flight crew : took evasive action
Consequence	Other
Miss Distance	horizontal : 150 vertical : 0
Supplementary
Primary Problem	Flight Crew Human Performance

Narrative:

Entered pattern via extended right base, made calls. Didn't hear other calls. Looked out and saw light single coming at me (offset to the right by 50-100 yards). He was on left base to 24. I made climbing turn to left and assumed pattern must be left hand for this field (pattern over homes and not open area). Should have entered 45 degree to downwind and made left hand turns, no shortcuts. First fixed wing flight in 5 years, forgot about that rule.

Original NASA ASRS Text

Title: NMAC IN TRAFFIC PATTERN.

Narrative: ENTERED PATTERN VIA EXTENDED RIGHT BASE, MADE CALLS. DIDN'T HEAR OTHER CALLS. LOOKED OUT AND SAW LIGHT SINGLE COMING AT ME (OFFSET TO THE RIGHT BY 50-100 YARDS). HE WAS ON LEFT BASE TO 24. I MADE CLBING TURN TO LEFT AND ASSUMED PATTERN MUST BE LEFT HAND FOR THIS FIELD (PATTERN OVER HOMES AND NOT OPEN AREA). SHOULD HAVE ENTERED 45 DEG TO DOWNWIND AND MADE LEFT HAND TURNS, NO SHORTCUTS. FIRST FIXED WING FLT IN 5 YEARS, FORGOT ABOUT THAT RULE.

Data retrieved from NASA's ASRS site as of August 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.