Unauthorized takeoff.

Attributes
ACN	109705
Time
Date	198904
Day	Wed
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : dca
State Reference	DC
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : corporate
Make Model Name	Small Transport, Low Wing, 2 Recip Eng
Flight Phase	climbout : takeoff
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : captain oversight : pic
Qualification	pilot : private pilot : instrument
Experience	flight time last 90 days : 75 flight time total : 7000 flight time type : 300
ASRS Report	109705
Person 2
Affiliation	Other
Function	flight crew : first officer
Events
Anomaly	non adherence : far non adherence : clearance other anomaly other
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance none taken : detected after the fact
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Before departing hpn filed 2 flight plans with bdr FSS; hpn direct dca, dca direct vrb. First leg no incidents. Started up at butler dca. Called clearance for IFR-vrb. No record in computer. They suggested we shut down and go back and re-file. We persuaded them to take flight plan by radio, 275, 279 FL180 vrb. Cleared to taxi to runway 33. Made a brief runup, called tower ready and they cleared us into position and hold 33. About 10 seconds later we heard, 'clearance delivery, caution wake turbulence aircraft landing 36, cleared for takeoff.' we responded 'abcd rolling.' after liftoff, pulled up to avoid any wake turbulence, turned right for a river departure northwest, then heard following on tower frequency. 'Abcd, that takeoff clearance was for another aircraft. You made an unauthorized takeoff. Change to departure...' remainder of trip, no incidents. Suggest that more care be taken by all parties when operations on multiple intersecting runways are taking place. We certainly should have reaffirmed the takeoff clearance because of the garbling, but the tower certainly could have told us to abort when he heard that we were rolling.

Original NASA ASRS Text

Title: UNAUTH TKOF.

Narrative: BEFORE DEPARTING HPN FILED 2 FLT PLANS WITH BDR FSS; HPN DIRECT DCA, DCA DIRECT VRB. FIRST LEG NO INCIDENTS. STARTED UP AT BUTLER DCA. CALLED CLRNC FOR IFR-VRB. NO RECORD IN COMPUTER. THEY SUGGESTED WE SHUT DOWN AND GO BACK AND RE-FILE. WE PERSUADED THEM TO TAKE FLT PLAN BY RADIO, 275, 279 FL180 VRB. CLRED TO TAXI TO RWY 33. MADE A BRIEF RUNUP, CALLED TWR READY AND THEY CLRED US INTO POS AND HOLD 33. ABOUT 10 SECS LATER WE HEARD, 'CD, CAUTION WAKE TURB ACFT LNDG 36, CLRED FOR TKOF.' WE RESPONDED 'ABCD ROLLING.' AFTER LIFTOFF, PULLED UP TO AVOID ANY WAKE TURB, TURNED RIGHT FOR A RIVER DEP NW, THEN HEARD FOLLOWING ON TWR FREQ. 'ABCD, THAT TKOF CLRNC WAS FOR ANOTHER ACFT. YOU MADE AN UNAUTH TKOF. CHANGE TO DEP...' REMAINDER OF TRIP, NO INCIDENTS. SUGGEST THAT MORE CARE BE TAKEN BY ALL PARTIES WHEN OPS ON MULTIPLE INTERSECTING RWYS ARE TAKING PLACE. WE CERTAINLY SHOULD HAVE REAFFIRMED THE TKOF CLRNC BECAUSE OF THE GARBLING, BUT THE TWR CERTAINLY COULD HAVE TOLD US TO ABORT WHEN HE HEARD THAT WE WERE ROLLING.

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.