Narrative:

At XA43 we reported on CTAF 119.4, B737 pushing back for departure runway 14 medford. Tower not open till XB00 local. At XA45 local we reported B737 taxiing for runway 14 medford. We noticed one aircraft in the pattern for runway 32 that reported downwind for runway 32. At XA50 we were released by cascade approach for departure. We verified the aircraft visually on downwind abeam midfield and reported on CTAF 'B737 departing runway 14 medford.' immediately we heard on CTAF 'I'm on my takeoff roll runway 32'. At the far end of the runway we noticed a cessna on takeoff roll. The first officer and I listened to CTAF the entire time and I only heard the aircraft on downwind. The first officer heard someone else on CTAF taxiing, but neither of us head them call 'taking runway 14 for takeoff.' we delayed our takeoff. This could have been a safety hazard if the other aircraft had not made the radio call 'I'm on takeoff roll runway 32.' factors affecting the situation. 1) runway 32 is the preferred runway -- were using runway 14 for our direction of flight to lax. 2) one other aircraft was in the pattern on downwind for runway 32 and when we were released by cascade approach we wanted to depart promptly to avoid a conflict with the downwind aircraft. Callback conversation with reporter revealed the following information: reporter did mention that there was a possibility that when his first officer was getting the clearance from approach control, he could have missed the cessna call because he was the only one listening to the CTAF frequency. There was also the possibility that the cessna aircraft could have made his previous announcements on the unicom frequency, which wasn't being monitored by them.

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Original NASA ASRS Text

Title: B737 BEGINS HIS TAKE OFF ROLL ON RWY 14 AT MFR, AS A CESSNA ACFT ANNOUNCES THAT HE'S TAKING OFF FROM THE OPPOSITE END OF THE SAME RWY.

Narrative: AT XA43 WE RPTED ON CTAF 119.4, B737 PUSHING BACK FOR DEP RWY 14 MEDFORD. TWR NOT OPEN TILL XB00 LCL. AT XA45 LCL WE RPTED B737 TAXIING FOR RWY 14 MEDFORD. WE NOTICED ONE ACFT IN THE PATTERN FOR RWY 32 THAT RPTED DOWNWIND FOR RWY 32. AT XA50 WE WERE RELEASED BY CASCADE APCH FOR DEP. WE VERIFIED THE ACFT VISUALLY ON DOWNWIND ABEAM MIDFIELD AND RPTED ON CTAF 'B737 DEPARTING RWY 14 MEDFORD.' IMMEDIATELY WE HEARD ON CTAF 'I'M ON MY TKOF ROLL RWY 32'. AT THE FAR END OF THE RWY WE NOTICED A CESSNA ON TKOF ROLL. THE FO AND I LISTENED TO CTAF THE ENTIRE TIME AND I ONLY HEARD THE ACFT ON DOWNWIND. THE FO HEARD SOMEONE ELSE ON CTAF TAXIING, BUT NEITHER OF US HEAD THEM CALL 'TAKING RWY 14 FOR TKOF.' WE DELAYED OUR TKOF. THIS COULD HAVE BEEN A SAFETY HAZARD IF THE OTHER ACFT HAD NOT MADE THE RADIO CALL 'I'M ON TKOF ROLL RWY 32.' FACTORS AFFECTING THE SITUATION. 1) RWY 32 IS THE PREFERRED RWY -- WERE USING RWY 14 FOR OUR DIRECTION OF FLT TO LAX. 2) ONE OTHER ACFT WAS IN THE PATTERN ON DOWNWIND FOR RWY 32 AND WHEN WE WERE RELEASED BY CASCADE APCH WE WANTED TO DEPART PROMPTLY TO AVOID A CONFLICT WITH THE DOWNWIND ACFT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR DID MENTION THAT THERE WAS A POSSIBILITY THAT WHEN HIS FO WAS GETTING THE CLEARANCE FROM APCH CONTROL, HE COULD HAVE MISSED THE CESSNA CALL BECAUSE HE WAS THE ONLY ONE LISTENING TO THE CTAF FREQ. THERE WAS ALSO THE POSSIBILITY THAT THE CESSNA ACFT COULD HAVE MADE HIS PREVIOUS ANNOUNCEMENTS ON THE UNICOM FREQ, WHICH WASN'T BEING MONITORED BY THEM.

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.