Less than standard separation between air carrier X and small transport Y. System error.

Attributes
ACN	126729
Time
Date	198910
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : iad
State Reference	VA
Altitude	agl bound lower : 75 agl bound upper : 75
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Controlling Facilities	tower : iad
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	ground : holding
Flight Plan	IFR
Aircraft 2
Make Model Name	Small Transport, Low Wing, 2 Recip Eng
Flight Phase	descent : approach landing : go around
Route In Use	approach : straight in
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 180 flight time total : 15000 flight time type : 180
ASRS Report	126729
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 240 flight time total : 11175 flight time type : 4000
ASRS Report	126726
Events
Anomaly	conflict : ground critical non adherence : required legal separation non adherence : published procedure
Independent Detector	other flight crewa
Resolutory Action	other
Consequence	faa : reviewed incident with flight crew Other
Miss Distance	horizontal : 0 vertical : 75
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

Air carrier X received clearance to 'position and hold' and acknowledged and read back by first officer. 2 mins later small transport Y called missed approach as he visually sighted us on the runway. He apparently was cleared to land FAF inbound prior to our position/hold clearance. When asked if there was a problem, tower replied they were delayed in our release which held us in position. Supplemental information from acn 126726: first officer heard the roar of reciprocating engines, looked up and saw a light twin doing a go-around. He missed us by about 75'. I don't recall hearing the tower clear him to land and the tower never told him to go around.

Original NASA ASRS Text

Title: LESS THAN STANDARD SEPARATION BETWEEN ACR X AND SMT Y. SYSTEM ERROR.

Narrative: ACR X RECEIVED CLRNC TO 'POSITION AND HOLD' AND ACKNOWLEDGED AND READ BACK BY F/O. 2 MINS LATER SMT Y CALLED MISSED APCH AS HE VISUALLY SIGHTED US ON THE RWY. HE APPARENTLY WAS CLRED TO LAND FAF INBND PRIOR TO OUR POSITION/HOLD CLRNC. WHEN ASKED IF THERE WAS A PROBLEM, TWR REPLIED THEY WERE DELAYED IN OUR RELEASE WHICH HELD US IN POSITION. SUPPLEMENTAL INFORMATION FROM ACN 126726: F/O HEARD THE ROAR OF RECIPROCATING ENGINES, LOOKED UP AND SAW A LIGHT TWIN DOING A GO-AROUND. HE MISSED US BY ABOUT 75'. I DON'T RECALL HEARING THE TWR CLEAR HIM TO LAND AND THE TWR NEVER TOLD HIM TO GO AROUND.

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.