Narrative:

We landed on runway 16R at sea. The tower told us to continue on the runway to taxiway P and I believe he said, exit on taxiway P and contact ground control crossing, or words to that effect. Instructions on when to contact ground seemed ambiguous, or incomplete. At the time, I did not realize my copilot switched to and contacted ground control while I exited runway 16R on taxiway P. We are now between runways 16R and 16L and on ground control. During his call to ground control I realized what he was doing and voiced my objections, but it was already done. Ground control asked where we were, but did not seem too upset about our position between runways and on his frequency. He told us to cross runway 16L and continue to the gate. Prior to crossing runway 16L I noticed there was an aircraft taking the runway 16L. That was the end of the situation. I am a reserve captain and I fly with a different copilot every trip. Although this was the most blatant example I have encountered, I find this to be not that unusual. It seems there are many coplts that will switch to ground frequency and contact them while still on an active runway. Emphasis needs to be placed on remaining with the tower frequency until clearing the active runway, or parallel runways. The tower needs to be specific with their instructions.

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Original NASA ASRS Text

Title: FO OF A B757 SWITCHED TO GND CTL PRIOR TO LEAVING THE ACTIVE RWY AND BEFORE BEING INSTRUCTED TO DO SO BY LCL CTL.

Narrative: WE LANDED ON RWY 16R AT SEA. THE TWR TOLD US TO CONTINUE ON THE RWY TO TXWY P AND I BELIEVE HE SAID, EXIT ON TXWY P AND CONTACT GND CTL XING, OR WORDS TO THAT EFFECT. INSTRUCTIONS ON WHEN TO CONTACT GND SEEMED AMBIGUOUS, OR INCOMPLETE. AT THE TIME, I DID NOT REALIZE MY COPLT SWITCHED TO AND CONTACTED GND CTL WHILE I EXITED RWY 16R ON TXWY P. WE ARE NOW BTWN RWYS 16R AND 16L AND ON GND CTL. DURING HIS CALL TO GND CTL I REALIZED WHAT HE WAS DOING AND VOICED MY OBJECTIONS, BUT IT WAS ALREADY DONE. GND CTL ASKED WHERE WE WERE, BUT DID NOT SEEM TOO UPSET ABOUT OUR POS BTWN RWYS AND ON HIS FREQ. HE TOLD US TO CROSS RWY 16L AND CONTINUE TO THE GATE. PRIOR TO XING RWY 16L I NOTICED THERE WAS AN ACFT TAKING THE RWY 16L. THAT WAS THE END OF THE SIT. I AM A RESERVE CAPT AND I FLY WITH A DIFFERENT COPLT EVERY TRIP. ALTHOUGH THIS WAS THE MOST BLATANT EXAMPLE I HAVE ENCOUNTERED, I FIND THIS TO BE NOT THAT UNUSUAL. IT SEEMS THERE ARE MANY COPLTS THAT WILL SWITCH TO GND FREQ AND CONTACT THEM WHILE STILL ON AN ACTIVE RWY. EMPHASIS NEEDS TO BE PLACED ON REMAINING WITH THE TWR FREQ UNTIL CLRING THE ACTIVE RWY, OR PARALLEL RWYS. THE TWR NEEDS TO BE SPECIFIC WITH THEIR INSTRUCTIONS.

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.