Narrative:

On arrival at the sdf, cpr X landed normally on the active runway (runway 19). On rollout and during the deceleration, tower asked which FBO we were going to. I replied, and they (tower) instructed left turn off the runway 19 onto the taxiway. I had apparently misunderstood the tower instructions (we turned left onto the taxiway and continued to taxi to the FBO without contacting ground control). As we continued taxiing we crossed runway 29 to continue to the FBO. After we crossed runway 29 tower replied cpr X contact ground control. Upon calling ground, ground control asked why we had not contacted them while taxiing. I replied we forgot to switch frequencys. Ground control also told us never to cross a runway without calling them. I had believed that we had been issued taxi instruction by sdf tower and that they were going to supervise our taxi to the FBO. Sdf at that time of the morning was slow (traffic-wise) and I thought that tower was also working ground. This frequently occurs elsewhere. I never heard tower's instructions to call ground control due to high cockpit noise levels during deceleration. Supplemental information from acn 251617: after clearing runway 19 at sdf, myself and the captain both thought we heard a clearance to monitor the tower and taxi to the ramp. After crossing an intersecting runway, we were told to contact ground and was then informed we were not cleared to taxi and definitely was not cleared to cross any intersecting runways. Factors contributing to the problem was bad audio and lack of attention and no readback of the clearance from tower. I try to make it a habit to verify clrncs with the other crew men, but due to low concentration on taxiing the aircraft, I failed to do so.

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Original NASA ASRS Text

Title: CPR Y NON ADHERENCE TO FAR CROSSED RWY WITHOUT CLRNC. RWY INCURSION.

Narrative: ON ARR AT THE SDF, CPR X LANDED NORMALLY ON THE ACTIVE RWY (RWY 19). ON ROLLOUT AND DURING THE DECELERATION, TWR ASKED WHICH FBO WE WERE GOING TO. I REPLIED, AND THEY (TWR) INSTRUCTED L TURN OFF THE RWY 19 ONTO THE TXWY. I HAD APPARENTLY MISUNDERSTOOD THE TWR INSTRUCTIONS (WE TURNED L ONTO THE TXWY AND CONTINUED TO TAXI TO THE FBO WITHOUT CONTACTING GND CTL). AS WE CONTINUED TAXIING WE CROSSED RWY 29 TO CONTINUE TO THE FBO. AFTER WE CROSSED RWY 29 TWR REPLIED CPR X CONTACT GND CTL. UPON CALLING GND, GND CTL ASKED WHY WE HAD NOT CONTACTED THEM WHILE TAXIING. I REPLIED WE FORGOT TO SWITCH FREQS. GND CTL ALSO TOLD US NEVER TO CROSS A RWY WITHOUT CALLING THEM. I HAD BELIEVED THAT WE HAD BEEN ISSUED TAXI INSTRUCTION BY SDF TWR AND THAT THEY WERE GOING TO SUPERVISE OUR TAXI TO THE FBO. SDF AT THAT TIME OF THE MORNING WAS SLOW (TFC-WISE) AND I THOUGHT THAT TWR WAS ALSO WORKING GND. THIS FREQUENTLY OCCURS ELSEWHERE. I NEVER HEARD TWR'S INSTRUCTIONS TO CALL GND CTL DUE TO HIGH COCKPIT NOISE LEVELS DURING DECELERATION. SUPPLEMENTAL INFO FROM ACN 251617: AFTER CLRING RWY 19 AT SDF, MYSELF AND THE CAPT BOTH THOUGHT WE HEARD A CLRNC TO MONITOR THE TWR AND TAXI TO THE RAMP. AFTER XING AN INTERSECTING RWY, WE WERE TOLD TO CONTACT GND AND WAS THEN INFORMED WE WERE NOT CLRED TO TAXI AND DEFINITELY WAS NOT CLRED TO CROSS ANY INTERSECTING RWYS. FACTORS CONTRIBUTING TO THE PROB WAS BAD AUDIO AND LACK OF ATTN AND NO READBACK OF THE CLRNC FROM TWR. I TRY TO MAKE IT A HABIT TO VERIFY CLRNCS WITH THE OTHER CREW MEN, BUT DUE TO LOW CONCENTRATION ON TAXIING THE ACFT, I FAILED TO DO SO.

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.