A nifty simulation of flying a lunar module. Takes a little while to get the hang of (there's some video tutorials included) but once you're flying around without any assists it's great fun.
Radio chatter and some fitting background music add atmosphere to a lunar environment that would otherwise have none (zing!). You will also have the opportunity to fly around a map on Mars where dust storms and increased gravity and drag make flying much more difficult.
Some physics knowledge is definitely a bonus. Physics nerds like myself will take pleasure in having to plan ahead, taking into account things like cargo weight, fuel efficiency, conservation of momentum and more. You will feel like you've mastered lunar flight when you line up a trajectory for the landing pad, using your RCS thrusters to reduce your transverse speed while throttling up your main thruster to keep the vector over the pad, to finish with a quick yaw at the end to line up a perfect landing.
Probably the biggest drawback to the game is the relative lack of mission variety with only three types. The environments are of course pretty barren as you'd expect so like with many flight simulators you are more occupied with what your craft is doing and how it's flying. This is where Lunar Flight really shines.
It supports TrackIR and Occulus Rift too so props to the developer!