Controller had less than standard separation between taxiing aircraft on runway and departing medium...

Attributes
ACN	80748
Time
Date	198801
Day	Wed
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : stl
State Reference	MO
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	tracon : n90
Make Model Name	Small Transport, Low Wing, 2 Recip Eng
Flight Phase	ground other : taxi landing other
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other
Flight Phase	climbout : takeoff
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : local
Qualification	controller : radar
ASRS Report	80748
Person 2
Function	flight crew : single pilot
Qualification	pilot : instrument
Events
Anomaly	conflict : ground critical incursion : runway non adherence : clearance non adherence : required legal separation
Independent Detector	other controllera
Resolutory Action	none taken : anomaly accepted
Consequence	Other
Miss Distance	horizontal : 2000 vertical : 0
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error Pilot Deviation
Situations
ATC Facility	procedure or policy : unspecified
Airport	other physical facility

Narrative:

Small transport X landed on runway 30R. As he slowed to taxi speed I instructed him to turn right onto taxiway romeo, which is located some 2500' from the approach end of the runway. He replied 'roger.' medium large transport Y was taxied into position and hold on 30R. I observed small transport X landing lights turn to the right an then to left as he taxied, indicating to me he had made a left turn onto the parallel taxiway foxtrot that is separated centerline to centerline by 500'. Small transport X made no other transmission to me indicating that he had missed the romeo taxiway, which indeed is what happened. Small transport X continued down to the next taxiway november, located some 2000' downfield from romeo. On taxiway foxtrot in between 'right' and 'north' to the north lies the FBO. On top of the 3 hangars lies 11 high intensity lights which cast a difficult glare onto their ramp as well as taxiway F and a small portion of 30R, at times making visibility difficult. With small transport X taxiing on the runway in between 'right' and 'north', medium large transport Y was clrd for takeoff. Small transport X clrd the runway as medium large transport Y rolled between 'right' and 'south' some 2000-3000' away.

Original NASA ASRS Text

Title: CTLR HAD LESS THAN STANDARD SEPARATION BETWEEN TAXIING ACFT ON RWY AND DEPARTING MLG.

Narrative: SMT X LANDED ON RWY 30R. AS HE SLOWED TO TAXI SPD I INSTRUCTED HIM TO TURN RIGHT ONTO TXWY ROMEO, WHICH IS LOCATED SOME 2500' FROM THE APCH END OF THE RWY. HE REPLIED 'ROGER.' MLG Y WAS TAXIED INTO POS AND HOLD ON 30R. I OBSERVED SMT X LNDG LIGHTS TURN TO THE RIGHT AN THEN TO LEFT AS HE TAXIED, INDICATING TO ME HE HAD MADE A LEFT TURN ONTO THE PARALLEL TXWY FOXTROT THAT IS SEPARATED CENTERLINE TO CENTERLINE BY 500'. SMT X MADE NO OTHER XMISSION TO ME INDICATING THAT HE HAD MISSED THE ROMEO TXWY, WHICH INDEED IS WHAT HAPPENED. SMT X CONTINUED DOWN TO THE NEXT TXWY NOVEMBER, LOCATED SOME 2000' DOWNFIELD FROM ROMEO. ON TXWY FOXTROT IN BTWN 'R' AND 'N' TO THE N LIES THE FBO. ON TOP OF THE 3 HANGARS LIES 11 HIGH INTENSITY LIGHTS WHICH CAST A DIFFICULT GLARE ONTO THEIR RAMP AS WELL AS TXWY F AND A SMALL PORTION OF 30R, AT TIMES MAKING VIS DIFFICULT. WITH SMT X TAXIING ON THE RWY IN BTWN 'R' AND 'N', MLG Y WAS CLRD FOR TKOF. SMT X CLRD THE RWY AS MLG Y ROLLED BTWN 'R' AND 'S' SOME 2000-3000' AWAY.

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.

Controller had less than standard separation between taxiing aircraft on runway and departing medium large transport.