Understanding timers

Timers represent the physical timing devices on your aircraft, such as tachometers and Hobbs meters. When timers are configured, component times are updated with every recorded flight.

Setting up timers is optional. Without timers, component times reflect the values from their most recent log entries. Timers are required to record flights.

Timer types

Tachometer — on most piston aircraft, tachometer time is the standard used to track maintenance intervals.

Hobbs — Hobbs readings can be recorded for reference, or used as the timing device for the airframe.

Component time

Component time is the accumulated service time for an aircraft component. Every component has a total time value reflecting the time it has been in service since manufacture. Components that can be overhauled, such as engines and propellers, can also record time since major overhaul. Airframes cannot be overhauled.

How component time is calculated

When a timer is used to track a component’s time, the component time and the timer reading are recorded at a specific point in time. Using that baseline, subsequent timer readings can be used to calculate the component time.

When a timer is replaced, the new timer’s reading is recorded with the component time to start a new baseline. The old timer will no longer be used to calculate component time beginning on the date it was replaced.