What do the abbreviations TBO, TCI, TIS, SC and TBR mean?
TBO - Time Before Overhaul
Allowed operating times between overhauls.
TCI- Time Check Interval
Interval at which certain checks must be performed
TIS - Time In Service
(previous) operating hours
SC - Since Check
Allowed time since last check
TBR - Time Before Remove
Permissible time until a component must be removed