The M55 Geophysica. This airplane is owned by a Russian corporation, the Myasishchev Design Bureau (MDB), and is used exclusively for scientific studies. It flies directly in the stratosphere at 65,000 feet altitude, about twice as high as a commercial airliner. It is manned by a single pilot, who sits in a very confined cockpit. Similar to US high altitude research planes, this aircraft was once used as a "spy plane."

Click here for a story from the London Financial Times detailing the conversion of this plane to use for environmental studies.