HS125 crew took off from runway 25L at lax without clearance.

Attributes
ACN	543064
Time
Date	200204
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : lax.airport
State Reference	CA
Altitude	agl single value : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : skbo.tower
Operator	common carrier : air taxi
Make Model Name	BAe 125 Series 800
Operating Under FAR Part	Part 135
Flight Phase	climbout : takeoff ground : takeoff roll
Flight Plan	IFR
Person 1
Affiliation	company : air taxi
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 150 flight time total : 4900 flight time type : 1000
ASRS Report	543064
Person 2
Affiliation	company : air taxi
Function	flight crew : captain oversight : pic
Events
Anomaly	non adherence : far non adherence : company policies non adherence : published procedure non adherence : clearance other anomaly other
Independent Detector	other controllera
Resolutory Action	none taken : detected after the fact
Consequence	faa : investigated faa : reviewed incident with flight crew
Supplementary
Problem Areas	Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

On apr/fri/02 I was assigned as sic on a part 135 passenger flight, scheduled to leave lax at XA15. I called clearance delivery at about XZ30 and received our clearance. I was told by clearance to contact ground about 2 mins prior to engine start. Our passenger boarded at about XA05 and we started engines to be ready to go. I called ground control and was immediately advised to contact clearance delivery. I called clearance and they advised me that we had a wheels up time of 18 past the hour and asked if we would be able to make that time. I advised them that we would and then told us to contact ground. I went back to ground and advised that we were ready to taxi. Ground cleared us to taxi to runway 25L via taxiway a and hold short of taxiway F. I acknowledged and we started our taxi. As we turned onto taxiway a, ground asked us to expedite our taxi to taxiway F and monitor tower. I switched to tower frequency and almost immediately the tower asked 'are you ready to go?' I responded that we were, and they cleared us into 'position and hold runway 25L.' I acknowledged and completed the aircraft line-up checks. I also made a cabin announcement to the passenger because it seemed that we were being rushed to depart. This was all done prior to reaching taxiway F. Because of the rush and trying to complete the line-up checks, I thought that I heard 'cleared for takeoff.' I asked the captain if we were cleared for takeoff just to verify it, and he stated yes. Upon reaching the runway, we started our takeoff roll. When the aircraft reached approximately 40-50 KTS, the tower called and I responded. The tower then said 'disregard.' we continued the takeoff and after getting airborne, departure control called and gave us a phone number to call. We called the number and were advised that we had taken off without a clearance. I believe the things that led up to this incident were: 1) the rush to get us out at our assigned time. 2) several frequency changes prior to taxi and during taxi. 3) communications from the tower, making it sound as if we needed to get airborne immediately. 4) our failure to verify that we were, in fact, cleared for takeoff. The problem would have been avoided if I had verified that we were or were not cleared for takeoff.

Original NASA ASRS Text

Title: HS125 CREW TOOK OFF FROM RWY 25L AT LAX WITHOUT CLRNC.

Narrative: ON APR/FRI/02 I WAS ASSIGNED AS SIC ON A PART 135 PAX FLT, SCHEDULED TO LEAVE LAX AT XA15. I CALLED CLRNC DELIVERY AT ABOUT XZ30 AND RECEIVED OUR CLRNC. I WAS TOLD BY CLRNC TO CONTACT GND ABOUT 2 MINS PRIOR TO ENG START. OUR PAX BOARDED AT ABOUT XA05 AND WE STARTED ENGS TO BE READY TO GO. I CALLED GND CTL AND WAS IMMEDIATELY ADVISED TO CONTACT CLRNC DELIVERY. I CALLED CLRNC AND THEY ADVISED ME THAT WE HAD A WHEELS UP TIME OF 18 PAST THE HR AND ASKED IF WE WOULD BE ABLE TO MAKE THAT TIME. I ADVISED THEM THAT WE WOULD AND THEN TOLD US TO CONTACT GND. I WENT BACK TO GND AND ADVISED THAT WE WERE READY TO TAXI. GND CLRED US TO TAXI TO RWY 25L VIA TXWY A AND HOLD SHORT OF TXWY F. I ACKNOWLEDGED AND WE STARTED OUR TAXI. AS WE TURNED ONTO TXWY A, GND ASKED US TO EXPEDITE OUR TAXI TO TXWY F AND MONITOR TWR. I SWITCHED TO TWR FREQ AND ALMOST IMMEDIATELY THE TWR ASKED 'ARE YOU READY TO GO?' I RESPONDED THAT WE WERE, AND THEY CLRED US INTO 'POS AND HOLD RWY 25L.' I ACKNOWLEDGED AND COMPLETED THE ACFT LINE-UP CHKS. I ALSO MADE A CABIN ANNOUNCEMENT TO THE PAX BECAUSE IT SEEMED THAT WE WERE BEING RUSHED TO DEPART. THIS WAS ALL DONE PRIOR TO REACHING TXWY F. BECAUSE OF THE RUSH AND TRYING TO COMPLETE THE LINE-UP CHKS, I THOUGHT THAT I HEARD 'CLRED FOR TKOF.' I ASKED THE CAPT IF WE WERE CLRED FOR TKOF JUST TO VERIFY IT, AND HE STATED YES. UPON REACHING THE RWY, WE STARTED OUR TKOF ROLL. WHEN THE ACFT REACHED APPROX 40-50 KTS, THE TWR CALLED AND I RESPONDED. THE TWR THEN SAID 'DISREGARD.' WE CONTINUED THE TKOF AND AFTER GETTING AIRBORNE, DEP CTL CALLED AND GAVE US A PHONE NUMBER TO CALL. WE CALLED THE NUMBER AND WERE ADVISED THAT WE HAD TAKEN OFF WITHOUT A CLRNC. I BELIEVE THE THINGS THAT LED UP TO THIS INCIDENT WERE: 1) THE RUSH TO GET US OUT AT OUR ASSIGNED TIME. 2) SEVERAL FREQ CHANGES PRIOR TO TAXI AND DURING TAXI. 3) COMS FROM THE TWR, MAKING IT SOUND AS IF WE NEEDED TO GET AIRBORNE IMMEDIATELY. 4) OUR FAILURE TO VERIFY THAT WE WERE, IN FACT, CLRED FOR TKOF. THE PROB WOULD HAVE BEEN AVOIDED IF I HAD VERIFIED THAT WE WERE OR WERE NOT CLRED FOR TKOF.

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.