B737NG target speed deviation during cruise
Dear all,
Sometimes I notice that the B737NG starts to deviate from the FMC target speed during cruise, and when the deviation becomes too big it adds thrust to correct for this. Although all settings in the FMC PERF INIT page are set-up correct and there are no significant temperature/wind deviations it tends to do this.
Could anyone of you, maybe a technician, come up with a reason for this (e.g. different FMC thrust/speed schedules).
Thank you for sharing your ideas and inputs.