Small transport on final approach has near midair collision with small aircraft.

Attributes
ACN	98283
Time
Date	198811
Day	Wed
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : iad
State Reference	VA
Altitude	msl bound lower : 1200 msl bound upper : 1200
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : iad tower : iad
Operator	common carrier : air carrier
Make Model Name	Small Transport, Low Wing, 2 Turboprop Eng
Flight Phase	descent : approach
Route In Use	approach : visual
Flight Plan	IFR
Aircraft 2
Make Model Name	Small Aircraft, Low Wing, 1 Eng, Fixed Gear
Flight Phase	cruise other cruise other
Person 1
Affiliation	company : air carrier
Function	other personnel
Qualification	other
ASRS Report	98283
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	conflict : nmac non adherence : far other anomaly other
Independent Detector	other flight crewa
Resolutory Action	none taken : unable
Consequence	faa : investigated
Miss Distance	horizontal : 0 vertical : 100
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

As air carrier-small transport was on a base leg to 19L traffic was called as an small aircraft a 11 O'clock at 2 mi. Flight acknowledged traffic and began turn to final on rollout of turn to final an small aircraft B was directly in front of flight. No evasive action was taken due to lack of time. Sep was estimated by pilot as 100' vertical, 0 latitude. Callback conversation with reporter revealed following information. The report was filed by a dispatcher who overheard the pilot make a report to the tower about the near midair collision. The tower was unaware of the presence of the small aircraft. The small aircraft did not land but continued on his flight. Reporter surmises that small aircraft pilot had no idea that he flew over iad airport. ATC was unable to determine who the pilot of the small aircraft was. Analyst advised reporter that third party reports would not afford immunity to the pilots involved in the incident.

Original NASA ASRS Text

Title: SMT ON FINAL APCH HAS NMAC WITH SMA.

Narrative: AS ACR-SMT WAS ON A BASE LEG TO 19L TFC WAS CALLED AS AN SMA A 11 O'CLOCK AT 2 MI. FLT ACKNOWLEDGED TFC AND BEGAN TURN TO FINAL ON ROLLOUT OF TURN TO FINAL AN SMA B WAS DIRECTLY IN FRONT OF FLT. NO EVASIVE ACTION WAS TAKEN DUE TO LACK OF TIME. SEP WAS ESTIMATED BY PLT AS 100' VERT, 0 LAT. CALLBACK CONVERSATION WITH RPTR REVEALED FOLLOWING INFO. THE RPT WAS FILED BY A DISPATCHER WHO OVERHEARD THE PLT MAKE A RPT TO THE TWR ABOUT THE NMAC. THE TWR WAS UNAWARE OF THE PRESENCE OF THE SMA. THE SMA DID NOT LAND BUT CONTINUED ON HIS FLT. RPTR SURMISES THAT SMA PLT HAD NO IDEA THAT HE FLEW OVER IAD ARPT. ATC WAS UNABLE TO DETERMINE WHO THE PLT OF THE SMA WAS. ANALYST ADVISED RPTR THAT THIRD PARTY RPTS WOULD NOT AFFORD IMMUNITY TO THE PLTS INVOLVED IN THE INCIDENT.

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.