The First 15 Minutes of Propeller Arena: Aviation Battle Championship (Dreamcast)

Copied from Sega Retro:

Propeller Arena: Aviation Battle Championship (プロペラ アリーナ) is an unreleased Sega Dreamcast combat flight simulator game developed by Sega-AM2 and scheduled to be published by Sega in late 2001. Reportedly finished and ready to be published, the game was cancelled at the last minute in response to the September 11, 2001 attacks on the United States of America. It is assumed that the "Tower City" stage was the main reason for this decision, as it is possible to fly around and crash planes in a city based on New York, and, according to Sega of America, allows "a determined individual to deliberately play the game in a manner that generates images similar to those we have seen on the news".

In the game, the player flies various planes across arenas and engages in dogfights, making it a spiritual sequel to Wing War. Propeller Arena was also designed with online multiplayer in mind, and had the servers been activated, would have supported the Dreamcast Microphone (except in Europe, where online play was not set to be featured).