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With the free base Microsoft Flight, you get a single plane, the Icon A5, and courses around the biggest island of Hawaii. By completing missions in the game, you can unlock a new paint scheme for your plane. From the marketplace, in-game, or in Steam, you can purchase the rest of the Hawaiian island chain and additional planes if you so choose.

The minimum and recommended requirements follow, copied from the official website.

Minimum:

OS:Windows XP (SP3)
Processor:Dual Core 2.0 GHz
Memory:2 GB RAM
Graphics:256 MB card capable of shader 3.0
DirectX®:9.0c
Hard Drive:10 GB HD space
Games for Windows – LIVE System Requirements:Multiplayer play and other LIVE features included at no charge; games may offer additional downloads that may require additional fees. LIVE is not available in all countries, visit www.xbox.com/en-US/live/countries for more information.Features and system requirements may change without notice. Subject to Terms of Use (at www.gamesforwindows.com/live/termsofuse). Broadband Internet service required (sold separately). Some broadband services may not work with LIVE and performance may vary. Under 13 requires parental consent. See www.gamesforwindows.com/live for full details.
Recommended:

OS:Windows 7 64-bit
Processor:Intel® Core™ i7 960 @ 3.20GHz, AMD® Phenom™ II X6 1100T 3.3 GHz
Memory:6 GB RAM
Graphics:ATI Radeon™ HD 5870, NVIDIA® GeForce® GTX 560
DirectX®:9.0c
Hard Drive:15 GB HD space
Other Requirements:Broadband Internet connection