[MereInterest]

Not having read the article, I am sure that they already did. Nothing gets sent beyond Earth's orbit without having gone through as much testing as is humanly possible on Earth. The cost of failure on Earth is several orders of magnitude less expensive than the cost of failure elsewhere.

I would guess that sending a test helicopter along with another rover would be to do a feasibility test for larger flight-based probes in the future. Test it now with a small helicopter, and you use 10-20 pounds of payload in order to do better wind and atmospheric studies. On the other hand, if you send a probe that uses flight as its primary mode of transportation, and some unknown unknown causes it to fail, you've scrapped the entire mission.

[dmurray]

They might not have, because it might just fall out of the sky. It's built to overcome Mars' gravity, not Earth's.

However I agree with you, they will be testing it extensively in as close to Martian conditions as they can achieve.

[TeMPOraL]

> They might not have, because it might just fall out of the sky. It's built to overcome Mars' gravity, not Earth's.

A video has them flying that thing inside a pressure chamber without payload, so at least in this configuration it has enough power to overcome Earth's gravity. Probably wouldn't lift off on Earth with the payload, though.