[Pete from Shawnee Mission]

They did the break in, now its time to throttle up! Vrroom or more likely in the thin atmosphere: "vrroosh"!

How far away from the rover can they get and maintain radio contact?

[Ezekiel]

I’ve forgotten, but if the ‘line of sight’ is messed up due to terrain, then they don’t talk.

https://mars.nasa.gov/technology/helicopter/status/466/hide-and-seek/