|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Local Time Of Day||0601 To 1200|
|Locale Reference||airport : phl.airport|
|Altitude||agl single value : 0|
|Operator||common carrier : air carrier|
|Make Model Name||Regional Jet 200 ER&LR|
|Operating Under FAR Part||Part 121|
|Flight Phase||ground : takeoff roll|
|Affiliation||government : faa|
|Function||controller : ground|
|Experience||controller time certified in position1 : 1|
controller time certified in position2 : 6
|Anomaly||conflict : ground less severe|
non adherence : clearance
|Independent Detector||other controllera|
|Resolutory Action||controller : issued new clearance|
flight crew : rejected takeoff
|Problem Areas||ATC Human Performance|
|Primary Problem||ATC Human Performance|
While staffing the ground control position at the phl ATC tower; I issued a clearance to an airport vehicle who was escorting a towed aircraft to 'proceed via taxiway Y and cross the 9L approach.' the vehicle said 'roger.' shortly thereafter; I observed this vehicle and the towed aircraft crossing midway down the active departure runway; runway 27L at taxiway Y. I immediately alerted the local controller who then canceled the takeoff clearance to a departing regional jet which had just started its takeoff roll. The aircraft quickly and safely came to a half and taxied off the runway. The problem developed when I misunderstood the driver's original (recorded) request which was to 'cross runway 27L at taxiway Y with towed aircraft.' I thought he wanted to proceed across the approach end of runway 9L which is parallel to runway 27L; both being bisected by the same taxiway Y. The problem was compounded when the driver heard what he wanted to hear and didn't read back the crossing instruction verbatim. This would have given me another opportunity to correct the misunderstanding. Possible solution: aircraft and vehicles shall read back all runway crossing clrncs verbatim.
Original NASA ASRS Text
Title: PHL GND CTLR DESCRIBED INCIDENT WHEN ARPT VEHICLE CROSSED RWY AT UNEXPECTED LOCATION; REQUIRING LCL CTLR TO CANCEL TKOF CLRNC.
Narrative: WHILE STAFFING THE GND CTL POS AT THE PHL ATC TWR; I ISSUED A CLRNC TO AN ARPT VEHICLE WHO WAS ESCORTING A TOWED ACFT TO 'PROCEED VIA TXWY Y AND CROSS THE 9L APCH.' THE VEHICLE SAID 'ROGER.' SHORTLY THEREAFTER; I OBSERVED THIS VEHICLE AND THE TOWED ACFT XING MIDWAY DOWN THE ACTIVE DEP RWY; RWY 27L AT TXWY Y. I IMMEDIATELY ALERTED THE LCL CTLR WHO THEN CANCELED THE TKOF CLRNC TO A DEPARTING REGIONAL JET WHICH HAD JUST STARTED ITS TKOF ROLL. THE ACFT QUICKLY AND SAFELY CAME TO A HALF AND TAXIED OFF THE RWY. THE PROB DEVELOPED WHEN I MISUNDERSTOOD THE DRIVER'S ORIGINAL (RECORDED) REQUEST WHICH WAS TO 'CROSS RWY 27L AT TXWY Y WITH TOWED ACFT.' I THOUGHT HE WANTED TO PROCEED ACROSS THE APCH END OF RWY 9L WHICH IS PARALLEL TO RWY 27L; BOTH BEING BISECTED BY THE SAME TXWY Y. THE PROB WAS COMPOUNDED WHEN THE DRIVER HEARD WHAT HE WANTED TO HEAR AND DIDN'T READ BACK THE XING INSTRUCTION VERBATIM. THIS WOULD HAVE GIVEN ME ANOTHER OPPORTUNITY TO CORRECT THE MISUNDERSTANDING. POSSIBLE SOLUTION: ACFT AND VEHICLES SHALL READ BACK ALL RWY XING CLRNCS VERBATIM.
Data retrieved from NASA's ASRS site as of January 2009 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.