Sorry to say... but... Day 2! Woot! I got a REALLY lucky day 1 ($10000). Day 2 was about using the e-rockets, full radar, and a lot of luck. Upgraded rockets aren't a bad idea either.
Mars in 3 days is hardly impossible :) There's a bit of luck involved during day 1, but beyond that, it's about finding the paddles and having good air time. My wife gets 3 days consistently, with a restart here and there.
 "Hedgehog Launch 2"){kind=icon}