According to a recent news announcement1, NASA is going to send a small helicopter to Mars for testing purposes. Future landers could carry more of these
future rotorcraft [that might] act as scouts and explore parts of Mars that rovers can't reach.
The article states the following about the initial deployment of the helicopter:
After landing, the rover will deposit its helicopter payload, then retreat to a safe distance while the rotorcraft take off.
If my understanding based upon what I have read is correct, the touchdown of landers is still a somewhat risky event, and new ways to protect landers from the impact on the surface are still an active topic of research. If so, could it be feasible to deploy the helicopter before the lander reaches the surface (thus evading the shock from the final impact), or does mid-air braking and stabilization pose an even greater problem for such a helicopter? (I assume putting some safety distance between the descending lander and the helicopter would be feasible by jettisoning the helicopter at a sufficiently divergent angle.)
1: I'm going to cite from the Washington Post article on the topic here, but many news outlets reported about this.