> For the complete documentation index, see [llms.txt](https://px4.gitbook.io/px4-user-guide/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://px4.gitbook.io/px4-user-guide/development/middleware/msg_docs/rtltimeestimate.md).

# RtlTimeEstimate

[source file](https://github.com/PX4/PX4-Autopilot/blob/main/msg/RtlTimeEstimate.msg)

```c
uint64 timestamp # time since system start (microseconds)

bool valid			# Flag indicating whether the time estiamtes are valid
float32 time_estimate		# [s] Estimated time for RTL
float32 safe_time_estimate	# [s] Same as time_estimate, but with safety factor and safety margin included (factor*t + margin)

```