Speed change report to ATC
In US, not knowing the regulation in other countries, pilots are requested to report to ATC if their speed changes by TAS 10kt or 5%, whichever greater, per FAR.
I think there are many situation to change TAS, ex. turbulence, climb, descend, even air temperature change.
I do not image an aircraft climbs at the filed TAS.
Then especially in small planes, pilots need to use the analog flight computer to calculate TAS.
But I have not heard this kind of reports.
Do pilots have to report in any environment? even with radar contact?
If I misunderstand or overlook some exception for this regulation, please let me know.
Thank you.