Narrative:

The problem arose when I called our maintenance coordinator in atlanta to report information on an aircraft that had been gathered on 2 legs. I used a poor choice of words to describe what we had experienced. The maintenance coordinator misunderstood what was said and declared we had had an uncommanded rudder event. The misunderstanding was further exacerbated by my selection of words in the logbook write-up. This is unfortunate as my intention was simply to have maintenance check the aircraft after experiencing an undetermined anomaly during the last takeoff. When I arrived at the aircraft in slc, I noticed the rudder trim was set approximately 2 units of left turn. I zeroed out the trim per procedure and informed the captain. The aircraft was heavy and flaps were at 1 degree for the takeoff. Rotation was at approximately 150 KTS. I had anticipated that the aircraft might roll right after liftoff, and it did. I corrected, but it took more aileron than I first expected to hold heading. I trimmed the rudder to approximately 2 units left rudder and the aircraft flew fine. When we left iah, the captain decided to leave the rudder set with approximately 2 units of left trim for his takeoff. The aircraft was again heavy and rotation was at approximately the same speed as in slc. Flaps were set at 1 degree. The runway was very rough and the captain lifted the nose slightly to keep the gear from bouncing down the runway. I felt a slight bump in my seat at rotation. From my perspective, I didn't perceive it as a movement of the aircraft. In retrospect, it could have been wheel caster, turbulence, jetblast or the rough runway. I asked the captain about the rudder pedals and he said they did not move. I perceived no roll, yaw, or pitch change other than the rotation that the captain commanded. I do not believe the aircraft experienced an uncommanded rudder input, and it flew as expected during the return flight to slc. The bump that was felt was described in the write-up as a 'kick' which was misunderstood as a rudder movement uncommanded. I made reference to 2 legs for the write-up. The first leg I did not believe warranted a write-up. However, with respect to giving as much information that might explain the bump during the last takeoff it was mistakenly included and referenced in the write-up.

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Original NASA ASRS Text

Title: A B737-300 FO HAD MISCOM WITH COMPANY MAINT CTLR ABOUT ACFT THAT WAS OUT OF TRIM LIMITS.

Narrative: THE PROB AROSE WHEN I CALLED OUR MAINT COORDINATOR IN ATLANTA TO RPT INFO ON AN ACFT THAT HAD BEEN GATHERED ON 2 LEGS. I USED A POOR CHOICE OF WORDS TO DESCRIBE WHAT WE HAD EXPERIENCED. THE MAINT COORDINATOR MISUNDERSTOOD WHAT WAS SAID AND DECLARED WE HAD HAD AN UNCOMMANDED RUDDER EVENT. THE MISUNDERSTANDING WAS FURTHER EXACERBATED BY MY SELECTION OF WORDS IN THE LOGBOOK WRITE-UP. THIS IS UNFORTUNATE AS MY INTENTION WAS SIMPLY TO HAVE MAINT CHK THE ACFT AFTER EXPERIENCING AN UNDETERMINED ANOMALY DURING THE LAST TKOF. WHEN I ARRIVED AT THE ACFT IN SLC, I NOTICED THE RUDDER TRIM WAS SET APPROX 2 UNITS OF L TURN. I ZEROED OUT THE TRIM PER PROC AND INFORMED THE CAPT. THE ACFT WAS HVY AND FLAPS WERE AT 1 DEG FOR THE TKOF. ROTATION WAS AT APPROX 150 KTS. I HAD ANTICIPATED THAT THE ACFT MIGHT ROLL RIGHT AFTER LIFTOFF, AND IT DID. I CORRECTED, BUT IT TOOK MORE AILERON THAN I FIRST EXPECTED TO HOLD HDG. I TRIMMED THE RUDDER TO APPROX 2 UNITS L RUDDER AND THE ACFT FLEW FINE. WHEN WE LEFT IAH, THE CAPT DECIDED TO LEAVE THE RUDDER SET WITH APPROX 2 UNITS OF L TRIM FOR HIS TKOF. THE ACFT WAS AGAIN HVY AND ROTATION WAS AT APPROX THE SAME SPD AS IN SLC. FLAPS WERE SET AT 1 DEG. THE RWY WAS VERY ROUGH AND THE CAPT LIFTED THE NOSE SLIGHTLY TO KEEP THE GEAR FROM BOUNCING DOWN THE RWY. I FELT A SLIGHT BUMP IN MY SEAT AT ROTATION. FROM MY PERSPECTIVE, I DIDN'T PERCEIVE IT AS A MOVEMENT OF THE ACFT. IN RETROSPECT, IT COULD HAVE BEEN WHEEL CASTER, TURB, JETBLAST OR THE ROUGH RWY. I ASKED THE CAPT ABOUT THE RUDDER PEDALS AND HE SAID THEY DID NOT MOVE. I PERCEIVED NO ROLL, YAW, OR PITCH CHANGE OTHER THAN THE ROTATION THAT THE CAPT COMMANDED. I DO NOT BELIEVE THE ACFT EXPERIENCED AN UNCOMMANDED RUDDER INPUT, AND IT FLEW AS EXPECTED DURING THE RETURN FLT TO SLC. THE BUMP THAT WAS FELT WAS DESCRIBED IN THE WRITE-UP AS A 'KICK' WHICH WAS MISUNDERSTOOD AS A RUDDER MOVEMENT UNCOMMANDED. I MADE REF TO 2 LEGS FOR THE WRITE-UP. THE FIRST LEG I DID NOT BELIEVE WARRANTED A WRITE-UP. HOWEVER, WITH RESPECT TO GIVING AS MUCH INFO THAT MIGHT EXPLAIN THE BUMP DURING THE LAST TKOF IT WAS MISTAKENLY INCLUDED AND REFED IN THE WRITE-UP.

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.