U.K. defense contractor QinetiQ knew enough to not use wax in its unmanned, solar powered test plane.

By keeping away from any melting materials, and sticking with lightweight carbon fibers, the company claims to have hit a new world record of 54 hours at more than 50,000 feet above New Mexico this week.

The current record is 30 hours and 24 minutes, set by Northrop Grumman's Global Hawk in March 2001.

But QinetiQ may have flown too close to the Sun after all, as the flight of its ultra-thin "Zephyr" was not witnessed by officials from the World Air Sports Federation.

The federation keeps and certifies records, the company said.

Absolutely no melty bits >>