Near midair collision between air carrier-medium large transport and air carrier-mdt on approach.

Attributes
ACN	100628
Time
Date	198812
Day	Sat
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : iad
State Reference	VA
Altitude	agl bound lower : 600 agl bound upper : 650
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : iad artcc : zkc
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	descent : approach
Route In Use	approach : straight in
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Medium Transport
Flight Phase	descent : approach
Route In Use	approach : visual
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 150 flight time total : 16000 flight time type : 600
ASRS Report	100628
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	conflict : nmac non adherence : clearance
Independent Detector	other flight crewa
Resolutory Action	flight crew : took evasive action
Consequence	faa : reviewed incident with flight crew
Miss Distance	horizontal : 400 vertical : 50
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

On approach straight-in from over tille, mdt cut us out claiming visual reference to us. Was cleared by approach to follow us but instead created imminent collision situation. We evaded to left, executed missed approach. Mdt followed us up to about 2000' over center of airport. We made several radio queries to tower and approach control about the intruder but received no proper response.

Original NASA ASRS Text

Title: NMAC BETWEEN ACR-MLG AND ACR-MDT ON APCH.

Narrative: ON APCH STRAIGHT-IN FROM OVER TILLE, MDT CUT US OUT CLAIMING VISUAL REFERENCE TO US. WAS CLRED BY APCH TO FOLLOW US BUT INSTEAD CREATED IMMINENT COLLISION SITUATION. WE EVADED TO LEFT, EXECUTED MISSED APCH. MDT FOLLOWED US UP TO ABOUT 2000' OVER CENTER OF ARPT. WE MADE SEVERAL RADIO QUERIES TO TWR AND APCH CTL ABOUT THE INTRUDER BUT RECEIVED NO PROPER RESPONSE.

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.