Close proximity 2 GA aircraft entering traffic pattern at non tower airport at night.

Attributes
ACN	161819
Time
Date	199011
Day	Tue
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : clm
State Reference	WA
Altitude	msl bound lower : 2000 msl bound upper : 2050
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Operator	general aviation : personal
Make Model Name	Small Transport, Low Wing, 2 Recip Eng
Flight Phase	descent other landing : go around
Route In Use	approach : visual
Flight Plan	IFR
Aircraft 2
Make Model Name	Small Aircraft
Flight Phase	descent other landing other
Person 1
Affiliation	Other
Function	flight crew : captain oversight : pic
Qualification	pilot : instrument pilot : commercial
Experience	flight time last 90 days : 25 flight time total : 5200 flight time type : 3200
ASRS Report	161819
Person 2
Affiliation	Other
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	conflict : nmac non adherence : far other spatial deviation
Independent Detector	other flight crewa
Resolutory Action	other
Consequence	Other
Miss Distance	vertical : 50
Supplementary
Primary Problem	Flight Crew Human Performance

Narrative:

We had just cancelled our IFR clearance from eug to clm and were proceeding VFR to the airport. The unicom told us the wind direction and said runway 26 was being utilized. No other traffic was mentioned. I announced that we would make a modified base leg (right-hand) and land on 26. As we turned we heard another aircraft with a weak radio ask about the runway. He did not announced his position. As we turned final at about 3 mi, which we announced, we heard him again saying he was on a 2 mi final. I never saw the aircraft, but the copilot did and asked me to pull up. We did so and made a 360 degree turn, following the aircraft to the field. Normally upon hearing another aircraft, I elect a full pattern to avoid conflicts, particularly at night or during low visibility conditions. We did not know that the aircraft was anywhere near the airport. In this instance a full pattern would have been a wiser choice since the slower flying aircraft could have detected us on the downwind leg. The overtaking aircraft clearly must give way, but at night, with lights on the ground as in this instance, the other aircraft, which also did not fly a pattern, had no knowledge of our location and therefore could not take evasive action.

Original NASA ASRS Text

Title: CLOSE PROX 2 GA ACFT ENTERING TRAFFIC PATTERN AT NON TWR ARPT AT NIGHT.

Narrative: WE HAD JUST CANCELLED OUR IFR CLRNC FROM EUG TO CLM AND WERE PROCEEDING VFR TO THE ARPT. THE UNICOM TOLD US THE WIND DIRECTION AND SAID RWY 26 WAS BEING UTILIZED. NO OTHER TFC WAS MENTIONED. I ANNOUNCED THAT WE WOULD MAKE A MODIFIED BASE LEG (RIGHT-HAND) AND LAND ON 26. AS WE TURNED WE HEARD ANOTHER ACFT WITH A WEAK RADIO ASK ABOUT THE RWY. HE DID NOT ANNOUNCED HIS POS. AS WE TURNED FINAL AT ABOUT 3 MI, WHICH WE ANNOUNCED, WE HEARD HIM AGAIN SAYING HE WAS ON A 2 MI FINAL. I NEVER SAW THE ACFT, BUT THE COPLT DID AND ASKED ME TO PULL UP. WE DID SO AND MADE A 360 DEG TURN, FOLLOWING THE ACFT TO THE FIELD. NORMALLY UPON HEARING ANOTHER ACFT, I ELECT A FULL PATTERN TO AVOID CONFLICTS, PARTICULARLY AT NIGHT OR DURING LOW VISIBILITY CONDITIONS. WE DID NOT KNOW THAT THE ACFT WAS ANYWHERE NEAR THE ARPT. IN THIS INSTANCE A FULL PATTERN WOULD HAVE BEEN A WISER CHOICE SINCE THE SLOWER FLYING ACFT COULD HAVE DETECTED US ON THE DOWNWIND LEG. THE OVERTAKING ACFT CLEARLY MUST GIVE WAY, BUT AT NIGHT, WITH LIGHTS ON THE GND AS IN THIS INSTANCE, THE OTHER ACFT, WHICH ALSO DID NOT FLY A PATTERN, HAD NO KNOWLEDGE OF OUR LOCATION AND THEREFORE COULD NOT TAKE EVASIVE ACTION.

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.