Synthetic Flying Machine was an early project of the The Olivia Tremor Control's Will Cullen Hart and Bill Doss, and Neutral Milk Hotel's Jeff Mangum. The band later went on to become known as the Olivia Tremor Control, before Mangum eventually left to focus on Neutral Milk Hotel. The band had only one official release to their name, Heaven is for Kids, but there are several other tape cassettes of music distributed among friends and collaborators. Many of the songs performed by Synthetic Flying Machine later became songs by Neutral Milk Hotel ("Arms So Real") or Olivia Tremor Control ("Shaving Spiders", "Opera House"). Jeff Mangum wrote a song about the band of the same name, which became "Up and Over" and finally "The King of Carrot Flowers Pt. 3" on In the Aeroplane Over the Sea.