Narrative:

Aircraft had 1 hydraulic system to standby in flight eliminating 1 yaw damper necessitating reduced airspeed and lower altitude than normal stored flight plan. This was an MEL item on large transport re rudder load limiter light on. The flight plan from the company was for the lower altitude. However, center in la questioned our slower than normal speed which made me think maybe the company didn't change the cruise speed on the filed flight plan. The speed was more than 5% less than would normally have been flight planned. After this occurrence, on subsequent frequencys I advised ATC that we were at a reduced speed. Possibly the company should make note on the flight plan that speed change was sent to ATC to preclude a possible flow problem.

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Original NASA ASRS Text

Title: ACFT WAS FLOWN AT A SPEED SLOWER THAN FLT PLANNED.

Narrative: ACFT HAD 1 HYD SYS TO STANDBY IN FLT ELIMINATING 1 YAW DAMPER NECESSITATING REDUCED AIRSPD AND LOWER ALT THAN NORMAL STORED FLT PLAN. THIS WAS AN MEL ITEM ON LGT RE RUDDER LOAD LIMITER LIGHT ON. THE FLT PLAN FROM THE COMPANY WAS FOR THE LOWER ALT. HOWEVER, CENTER IN LA QUESTIONED OUR SLOWER THAN NORMAL SPD WHICH MADE ME THINK MAYBE THE COMPANY DIDN'T CHANGE THE CRUISE SPD ON THE FILED FLT PLAN. THE SPD WAS MORE THAN 5% LESS THAN WOULD NORMALLY HAVE BEEN FLT PLANNED. AFTER THIS OCCURRENCE, ON SUBSEQUENT FREQS I ADVISED ATC THAT WE WERE AT A REDUCED SPD. POSSIBLY THE COMPANY SHOULD MAKE NOTE ON THE FLT PLAN THAT SPD CHANGE WAS SENT TO ATC TO PRECLUDE A POSSIBLE FLOW PROB.

Data retrieved from NASA's ASRS site as of August 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.