Heavy transport cargo aircraft takes off on another aircraft's clearance.

Attributes
ACN	128701
Time
Date	198911
Day	Thu
Local Time Of Day	0001 To 0600
Place
Locale Reference	airport : sdf
State Reference	KY
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Heavy Transport, Low Wing, 4 Turbojet Eng
Flight Phase	climbout : takeoff ground : holding
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	climbout : takeoff ground : holding
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : flight engineer pilot : commercial pilot : atp
Experience	flight time last 90 days : 175 flight time total : 11000 flight time type : 1100
ASRS Report	128701
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp pilot : cfi pilot : flight engineer
Experience	flight time last 90 days : 140 flight time total : 16000 flight time type : 2000
ASRS Report	128660
Events
Anomaly	non adherence : clearance other anomaly other
Independent Detector	other flight crewa
Resolutory Action	none taken : detected after the fact
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation Operational Deviation

Narrative:

For taxi-out, we were cleared to the long n-s runway. Another aircraft, same airline and with similar call sign, was already taxiing to the intersecting e-w runway. When approximately 500' from the runway end, we seemingly heard our call sign and cleared for takeoff, which we read back to tower. Fortunately for us, upon initiating our takeoff roll, my conscientious first officer transmitted our 'call sign, rolling,' which was acknowledged by tower. The other aircraft, upon hearing this, stopped his takeoff. Just after we were airborne he stated to tower that he was holding his takeoff, as we had seemingly taken off on his clearance. A mid-runway or midair collision potential definitely existed. Contributing factors include: 1) aircraft with same company, similar #'ed call signs, taxiing to different, intersecting runways. 2) late at night, with tower duplexing on all frequencys, with aircraft (possibly) on different frequencys, unaware of each other's progress.

Original NASA ASRS Text

Title: HVT CARGO ACFT TAKES OFF ON ANOTHER ACFT'S CLRNC.

Narrative: FOR TAXI-OUT, WE WERE CLRED TO THE LONG N-S RWY. ANOTHER ACFT, SAME AIRLINE AND WITH SIMILAR CALL SIGN, WAS ALREADY TAXIING TO THE INTERSECTING E-W RWY. WHEN APPROX 500' FROM THE RWY END, WE SEEMINGLY HEARD OUR CALL SIGN AND CLRED FOR TKOF, WHICH WE READ BACK TO TWR. FORTUNATELY FOR US, UPON INITIATING OUR TKOF ROLL, MY CONSCIENTIOUS F/O XMITTED OUR 'CALL SIGN, ROLLING,' WHICH WAS ACKNOWLEDGED BY TWR. THE OTHER ACFT, UPON HEARING THIS, STOPPED HIS TKOF. JUST AFTER WE WERE AIRBORNE HE STATED TO TWR THAT HE WAS HOLDING HIS TKOF, AS WE HAD SEEMINGLY TAKEN OFF ON HIS CLRNC. A MID-RWY OR MIDAIR COLLISION POTENTIAL DEFINITELY EXISTED. CONTRIBUTING FACTORS INCLUDE: 1) ACFT WITH SAME COMPANY, SIMILAR #'ED CALL SIGNS, TAXIING TO DIFFERENT, INTERSECTING RWYS. 2) LATE AT NIGHT, WITH TWR DUPLEXING ON ALL FREQS, WITH ACFT (POSSIBLY) ON DIFFERENT FREQS, UNAWARE OF EACH OTHER'S PROGRESS.

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.