Narrative:

We were cleared into position and hold on runway 7. This 4000 ft runway has a significant hill that crests right in the middle of it. Thus, planes on one end can't see planes that cross on the far end of the runway. We'd been in position and hold for about 90 seconds -- enough to make me uncomfortable and want to query ATC in case they'd forgotten about us. There was an instructor in the right seat, as this was a BFR. Throughout the time we were on the runway, he was chatting quite a bit about how business was for him and for the place where he instructed. The tower addressed a clearance to us. I caught our call sign, but I couldn't quite make out everything the tower said. It seemed to me, I assumed that the tower cleared us for takeoff and repeated our class C VFR departure procedure. The CFI in the right seat kept talking throughout the tower's clearance. I read back '(call sign), cleared for takeoff,' and started to advance the throttle. The tower replied that we were not cleared for takeoff, that he had just advised us that traffic was crossing on the runway up ahead, and that we should remain in position and hold. About 15 seconds later, he cleared us for takeoff, and the flight proceeded uneventfully. Evaluation: this incident fits in with the increasing concern of late about runway incursion accidents. Ordinarily, I maintain a sterile cockpit when on an active runway, since that's an uncomfortable place to be, and I want to be fully aware not just of clrncs directed to me but of clrncs directed to other aircraft (eg, to land on the runway where I'm sitting). Here, I ceded some of my PIC authority/authorized to the CFI in the right seat because it was a BFR. Had he been a passenger, I would have told him (nicely) not to talk while we were awaiting clearance for takeoff. I assumed without actually hearing the words that ATC had cleared us for takeoff, simply because that clearance was what would logically be directed to us in our situation. Obviously, I ought not to have assumed that, and should have asked for a readback of the clearance. Lack of familiarity with the airport also played a part. I didn't realize that other aircraft could cross the runway ahead of me in such a way that I couldn't see them. The poor quality of the radios in the rental aircraft also played a part. Lesson learned: maintain a sterile cockpit when awaiting clrncs to taxi onto a runway or when cleared into position and hold.

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Original NASA ASRS Text

Title: A PA28 PLT MISUNDERSTOOD CLRNC AND STARTED TKOF ROLL WITHOUT CLRNC.

Narrative: WE WERE CLRED INTO POS AND HOLD ON RWY 7. THIS 4000 FT RWY HAS A SIGNIFICANT HILL THAT CRESTS RIGHT IN THE MIDDLE OF IT. THUS, PLANES ON ONE END CAN'T SEE PLANES THAT CROSS ON THE FAR END OF THE RWY. WE'D BEEN IN POS AND HOLD FOR ABOUT 90 SECONDS -- ENOUGH TO MAKE ME UNCOMFORTABLE AND WANT TO QUERY ATC IN CASE THEY'D FORGOTTEN ABOUT US. THERE WAS AN INSTRUCTOR IN THE R SEAT, AS THIS WAS A BFR. THROUGHOUT THE TIME WE WERE ON THE RWY, HE WAS CHATTING QUITE A BIT ABOUT HOW BUSINESS WAS FOR HIM AND FOR THE PLACE WHERE HE INSTRUCTED. THE TWR ADDRESSED A CLRNC TO US. I CAUGHT OUR CALL SIGN, BUT I COULDN'T QUITE MAKE OUT EVERYTHING THE TWR SAID. IT SEEMED TO ME, I ASSUMED THAT THE TWR CLRED US FOR TKOF AND REPEATED OUR CLASS C VFR DEP PROC. THE CFI IN THE R SEAT KEPT TALKING THROUGHOUT THE TWR'S CLRNC. I READ BACK '(CALL SIGN), CLRED FOR TKOF,' AND STARTED TO ADVANCE THE THROTTLE. THE TWR REPLIED THAT WE WERE NOT CLRED FOR TKOF, THAT HE HAD JUST ADVISED US THAT TFC WAS XING ON THE RWY UP AHEAD, AND THAT WE SHOULD REMAIN IN POS AND HOLD. ABOUT 15 SECONDS LATER, HE CLRED US FOR TKOF, AND THE FLT PROCEEDED UNEVENTFULLY. EVALUATION: THIS INCIDENT FITS IN WITH THE INCREASING CONCERN OF LATE ABOUT RWY INCURSION ACCIDENTS. ORDINARILY, I MAINTAIN A STERILE COCKPIT WHEN ON AN ACTIVE RWY, SINCE THAT'S AN UNCOMFORTABLE PLACE TO BE, AND I WANT TO BE FULLY AWARE NOT JUST OF CLRNCS DIRECTED TO ME BUT OF CLRNCS DIRECTED TO OTHER ACFT (EG, TO LAND ON THE RWY WHERE I'M SITTING). HERE, I CEDED SOME OF MY PIC AUTH TO THE CFI IN THE R SEAT BECAUSE IT WAS A BFR. HAD HE BEEN A PAX, I WOULD HAVE TOLD HIM (NICELY) NOT TO TALK WHILE WE WERE AWAITING CLRNC FOR TKOF. I ASSUMED WITHOUT ACTUALLY HEARING THE WORDS THAT ATC HAD CLRED US FOR TKOF, SIMPLY BECAUSE THAT CLRNC WAS WHAT WOULD LOGICALLY BE DIRECTED TO US IN OUR SIT. OBVIOUSLY, I OUGHT NOT TO HAVE ASSUMED THAT, AND SHOULD HAVE ASKED FOR A READBACK OF THE CLRNC. LACK OF FAMILIARITY WITH THE ARPT ALSO PLAYED A PART. I DIDN'T REALIZE THAT OTHER ACFT COULD CROSS THE RWY AHEAD OF ME IN SUCH A WAY THAT I COULDN'T SEE THEM. THE POOR QUALITY OF THE RADIOS IN THE RENTAL ACFT ALSO PLAYED A PART. LESSON LEARNED: MAINTAIN A STERILE COCKPIT WHEN AWAITING CLRNCS TO TAXI ONTO A RWY OR WHEN CLRED INTO POS AND HOLD.

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.