Propeller Arena: Aviation Battle Championship is a video game for the Dreamcast console. It was originally titled Propeller Head Online,[1] and was to be released on 9/19/2001.[2] The game was trademarked on 8/14/2001.[3] It was developed and completed by the development team Sega AM2,[4] but the game was never officially released.[5] The release was cancelled[6] just days after the September 11 attacks,[7] citing both similarities in game packaging and design to the events of that day[8][9][10][11] as well as the Dreamcast's declining market share[12] resulting in projected low sales numbers. The game was on display at E3 on May 19, 2001.[13] After it was postponed, they were working to change the game cover art to remove sensitive images.[14] Hopes of a port to another console never materialized. However, a disk image of the game was eventually leaked,[15] and became a popular[16] download on many peer-to-peer networks.