Flight simulation is not a genre everyone is going to love. The learning curve is steep and takes patience. Free flight sims are a perfect way to introduce yourself into the flight sim world. When you are flying like an expert, maybe you too can help out in the development.
"FlightGear" is an open-source project developed by a community of gamers looking for a solution to their needs the publishing giants was not solving. You won't find a flashy game with no substance here. Realism is what it's all about.

Screenshot © HiTech Creations, Inc.A World War II flight sim that offers free offline and 8 person head-to-head play. You have a choice of 50 aircraft from 6 different countries. Man tanks, carriers, cruisers, and many more. There is a subscription fee for online play; the download comes with 2 weeks free.
"Flight Sim Model" is another civilian flight sim game offered free by the developer. The graphics are impressive for a free flight sim. A manual and FAQ is posted on the site.