In 1999 NASA's solar-powered, unmanned Helios Prototype aircraft took to the air with the goal of achieving sustained flight at 100,000 feet — and now you can relive the experience through images. As part of its daily "history of spaceflight" series, Space.com has posted a 13-year-old photo of the massive craft — which had a wingspan of 247 feet — but if you want more, NASA has a pretty large archive of images spanning the Helios' lifetime, from 1999 to 2003. While it never cracked 100,000 feet, in 2001 the craft reached an altitude of 96,863 feet, setting a new world record for sustained horizontal flight for a winged aircraft. Unfortunately, in 2003 the prototype came to an unceremonious end when it experienced structural failure during a flight on the Hawaiian island of Kauai, which caused it to crash into the Pacific Ocean. Not only was the Helios destroyed, but its experimental fuel cell system was also lost for good.