Narrative:

On may/xx/94 at burbank, ca, airport, at about 00 local time, I obtained a WX briefing for a VFR round robin flight to santa barbara. I completed my preflight, obtained the ATIS, a departure clearance and taxi instructions to runway 15. I did my runup and reported ready at 15 to the tower. The tower directed me to hold short of runway 15. I acknowledged and held short. An air carrier 737 taxied up on taxiway alpha, across the runway, obtained takeoff clearance and taxied onto the runway and took off. During the 737 takeoff run, I observed and mentally noted the 737's rotation point. About this time the tower cleared me onto runway 15 cautioning me of jet blast and the clearance was 'at my discretion.' I read back the instruction. After I watched the 737 well out of any danger for jet blast I taxied to the near end of runway 15, stopped, dropped 10 degrees of flaps and applied full throttle with the brakes on, turned on my transponder and strobe lights, and released brakes for a short field takeoff to be clearly above the wake turbulence. The tower asked me to turn right, which I acknowledged and turned right at about 400 ft AGL. The tower asked me to call the tower which I did upon landing. I was informed that I had not been given clearance for takeoff. It seems that there was a commercial aircraft on final for runway 8, an intersecting runway. As I completed my turn at about 500 ft AGL, I observed the aircraft on final and touching down. In my mind, at least, the clearance on the runway coupled with the 'at your discretion' and the warning about the recently departed aircraft equated to a clearance for takeoff as soon as I was assured that the preceding aircraft presented no hazard. I thought that I was cleared to takeoff. There is no reason in the world for me to be given position and hold in the presence of jet blast, if I would have to remain on the runway for several minutes while another aircraft landed on another runway and taxied across my runway as is required to reach the terminal. I was unaware of any impending landing of another aircraft. Neither end of runway 8/26 nor the approach to runway 8 is visible from runway 15 due to the presence of many large hangars. There was no conflict, no go around, no near miss, only communications reception or comprehension problem. Corrective actions for the pilot: comprehend and remember what you hear, even if it would appear illogical. Avoid any 'at your discretion' decisions to act unless you fully comprehend the possibilities. Don't equate a 'caution wake turbulence or jet blast' warning as being necessarily coupled with a takeoff or landing clearance. For the air traffic controller: avoid 'position and hold' orders if there's clearly going to be a substantial wait or if there is a risk of danger from a preceding aircraft. Avoid 'at your discretion' directions. If there is a mandatory clearance needed shortly thereafter to avoid the pilot considering the discretionary action to be greater than intended by the ATC.

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Original NASA ASRS Text

Title: UNAUTH TKOF PENETRATION OF CLASS D AIRSPACE.

Narrative: ON MAY/XX/94 AT BURBANK, CA, ARPT, AT ABOUT 00 LCL TIME, I OBTAINED A WX BRIEFING FOR A VFR ROUND ROBIN FLT TO SANTA BARBARA. I COMPLETED MY PREFLT, OBTAINED THE ATIS, A DEP CLRNC AND TAXI INSTRUCTIONS TO RWY 15. I DID MY RUNUP AND RPTED READY AT 15 TO THE TWR. THE TWR DIRECTED ME TO HOLD SHORT OF RWY 15. I ACKNOWLEDGED AND HELD SHORT. AN ACR 737 TAXIED UP ON TXWY ALPHA, ACROSS THE RWY, OBTAINED TKOF CLRNC AND TAXIED ONTO THE RWY AND TOOK OFF. DURING THE 737 TKOF RUN, I OBSERVED AND MENTALLY NOTED THE 737'S ROTATION POINT. ABOUT THIS TIME THE TWR CLRED ME ONTO RWY 15 CAUTIONING ME OF JET BLAST AND THE CLRNC WAS 'AT MY DISCRETION.' I READ BACK THE INSTRUCTION. AFTER I WATCHED THE 737 WELL OUT OF ANY DANGER FOR JET BLAST I TAXIED TO THE NEAR END OF RWY 15, STOPPED, DROPPED 10 DEGS OF FLAPS AND APPLIED FULL THROTTLE WITH THE BRAKES ON, TURNED ON MY XPONDER AND STROBE LIGHTS, AND RELEASED BRAKES FOR A SHORT FIELD TKOF TO BE CLRLY ABOVE THE WAKE TURB. THE TWR ASKED ME TO TURN R, WHICH I ACKNOWLEDGED AND TURNED R AT ABOUT 400 FT AGL. THE TWR ASKED ME TO CALL THE TWR WHICH I DID UPON LNDG. I WAS INFORMED THAT I HAD NOT BEEN GIVEN CLRNC FOR TKOF. IT SEEMS THAT THERE WAS A COMMERCIAL ACFT ON FINAL FOR RWY 8, AN INTERSECTING RWY. AS I COMPLETED MY TURN AT ABOUT 500 FT AGL, I OBSERVED THE ACFT ON FINAL AND TOUCHING DOWN. IN MY MIND, AT LEAST, THE CLRNC ON THE RWY COUPLED WITH THE 'AT YOUR DISCRETION' AND THE WARNING ABOUT THE RECENTLY DEPARTED ACFT EQUATED TO A CLRNC FOR TKOF AS SOON AS I WAS ASSURED THAT THE PRECEDING ACFT PRESENTED NO HAZARD. I THOUGHT THAT I WAS CLRED TO TKOF. THERE IS NO REASON IN THE WORLD FOR ME TO BE GIVEN POS AND HOLD IN THE PRESENCE OF JET BLAST, IF I WOULD HAVE TO REMAIN ON THE RWY FOR SEVERAL MINUTES WHILE ANOTHER ACFT LANDED ON ANOTHER RWY AND TAXIED ACROSS MY RWY AS IS REQUIRED TO REACH THE TERMINAL. I WAS UNAWARE OF ANY IMPENDING LNDG OF ANOTHER ACFT. NEITHER END OF RWY 8/26 NOR THE APCH TO RWY 8 IS VISIBLE FROM RWY 15 DUE TO THE PRESENCE OF MANY LARGE HANGARS. THERE WAS NO CONFLICT, NO GAR, NO NEAR MISS, ONLY COMS RECEPTION OR COMPREHENSION PROB. CORRECTIVE ACTIONS FOR THE PLT: COMPREHEND AND REMEMBER WHAT YOU HEAR, EVEN IF IT WOULD APPEAR ILLOGICAL. AVOID ANY 'AT YOUR DISCRETION' DECISIONS TO ACT UNLESS YOU FULLY COMPREHEND THE POSSIBILITIES. DON'T EQUATE A 'CAUTION WAKE TURB OR JET BLAST' WARNING AS BEING NECESSARILY COUPLED WITH A TKOF OR LNDG CLRNC. FOR THE AIR TFC CTLR: AVOID 'POS AND HOLD' ORDERS IF THERE'S CLRLY GOING TO BE A SUBSTANTIAL WAIT OR IF THERE IS A RISK OF DANGER FROM A PRECEDING ACFT. AVOID 'AT YOUR DISCRETION' DIRECTIONS. IF THERE IS A MANDATORY CLRNC NEEDED SHORTLY THEREAFTER TO AVOID THE PLT CONSIDERING THE DISCRETIONARY ACTION TO BE GREATER THAN INTENDED BY THE ATC.

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.