Narrative:

Small aircraft X was taxied by ground control for an intersection departure to runway 34 via taxiway B. A student pilot and instructor pilot were on board. After completing a runup, the small aircraft called local control ready for takeoff and requested additional room. (The distance remaining on runway 34 from B was 2600 ft. The distance remaining from the runway intersection with runway 23L is 2900 ft.) local control advised the small aircraft that a back taxi was approved and then issued the following clearance. 'Nxxxx runway 34 intersection departure at runway 23L cleared for takeoff.' it is important to note that as the clearance was issued the small aircraft was still back taxiing toward the runway intersection. Ground control then noticed the small aircraft appear to be starting to takeoff on runway 23L. He abruptly told an air carrier Y to hold short of runway 23L. The local control attempted to stop the small aircraft but it was too late. The small aircraft had departed on an inactive runway that was delegated to ground control. Both the pilot and student pilot believed that they were cleared for takeoff on runway 23L. The phraseology used in the clearance was correct and is new in the most recent change to FAA handbook 7110.65. However, when using this phraseology at runway intxns, pilots can become confused. There is also the potential that the first part of the clearance could be 'stepped on,' leaving only the last half of the clearance. In this case, 'runway 23L cleared for takeoff.' suggest that phraseology be modified for intersection departures from runway intxns to state 'runway xx intersection departure cleared for takeoff.' leave out the reference to the other runway.

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Original NASA ASRS Text

Title: CTLR CLRED SMA FOR TKOF AT RWY INTXN. SMA DEPARTED ON WRONG RWY CONFLICTING WITH AN ACR GOING INTO POS.

Narrative: SMA X WAS TAXIED BY GND CTL FOR AN INTXN DEP TO RWY 34 VIA TXWY B. A STUDENT PLT AND INSTRUCTOR PLT WERE ON BOARD. AFTER COMPLETING A RUNUP, THE SMA CALLED LCL CTL READY FOR TKOF AND REQUESTED ADDITIONAL ROOM. (THE DISTANCE REMAINING ON RWY 34 FROM B WAS 2600 FT. THE DISTANCE REMAINING FROM THE RWY INTXN WITH RWY 23L IS 2900 FT.) LCL CTL ADVISED THE SMA THAT A BACK TAXI WAS APPROVED AND THEN ISSUED THE FOLLOWING CLRNC. 'NXXXX RWY 34 INTXN DEP AT RWY 23L CLRED FOR TKOF.' IT IS IMPORTANT TO NOTE THAT AS THE CLRNC WAS ISSUED THE SMA WAS STILL BACK TAXIING TOWARD THE RWY INTXN. GND CTL THEN NOTICED THE SMA APPEAR TO BE STARTING TO TKOF ON RWY 23L. HE ABRUPTLY TOLD AN ACR Y TO HOLD SHORT OF RWY 23L. THE LCL CTL ATTEMPTED TO STOP THE SMA BUT IT WAS TOO LATE. THE SMA HAD DEPARTED ON AN INACTIVE RWY THAT WAS DELEGATED TO GND CTL. BOTH THE PLT AND STUDENT PLT BELIEVED THAT THEY WERE CLRED FOR TKOF ON RWY 23L. THE PHRASEOLOGY USED IN THE CLRNC WAS CORRECT AND IS NEW IN THE MOST RECENT CHANGE TO FAA HANDBOOK 7110.65. HOWEVER, WHEN USING THIS PHRASEOLOGY AT RWY INTXNS, PLTS CAN BECOME CONFUSED. THERE IS ALSO THE POTENTIAL THAT THE FIRST PART OF THE CLRNC COULD BE 'STEPPED ON,' LEAVING ONLY THE LAST HALF OF THE CLRNC. IN THIS CASE, 'RWY 23L CLRED FOR TKOF.' SUGGEST THAT PHRASEOLOGY BE MODIFIED FOR INTXN DEPS FROM RWY INTXNS TO STATE 'RWY XX INTXN DEP CLRED FOR TKOF.' LEAVE OUT THE REF TO THE OTHER RWY.

Data retrieved from NASA's ASRS site as of July 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.