Wikipedia
AlphaSim was a flight-simulation addon developer, based in the Bay of Plenty, New Zealand. The company was well known throughout the flight simulation community for their numerous highly detailed & realistic military simulation products. They developed both aircraft and scenery for the Microsoft Flight Simulator series. AlphaSim was renowned for developing often-niche aircraft as well as mainstream interests. On August 18, 2010, AlphaSim announced, "[We have] ceased trading. Due to circumstances beyond our control, this site will no longer be selling FS addons."
The website has since been shut down, and many workers from the AlphaSim team have opened a new company called Virtavia. Virtavia sells FSX addons through their own site, and third party vender sites such as Flight1.com.
The AlphaSim logo has evolved over the years. The final design was an aircraft creating an Alpha symbol with a smoke trail; logo was created in 2005.