Perlan II is on target to reach the stratosphere and a new altitude record for manned flight without an engine.
Airbus‘ Perlan team, which in 2006 set the record their now trying to break, is led by Einar Enevoldson, a former NASA test pilot. While Enevoldson was working as a high-altitude test pilot, he came up with a theory which would allow an engineless glider to reach previously undreamt of heights at specific areas in the world. Enevoldson set the previous record for manned flight-altitude in a glider after gaining the sponsorship of Steve Fossett, who set many records before his death in 2007 and was the first person to fly solo nonstop around the globe in a balloon. The Perlan I managed to reach a height of 50,720 feet in 2006, but now that record looks to be in danger as the Perlan II is reportedly expected to reach a height of approximately 90,000 feet.
Using streams of wind which head steadily upwards after being diverted by mountains, the glider is fully capable of heading into the stratosphere. It’s important to make use of these “mountain waves”, as the wind streams are called, in areas of polar vortex. These are areas close to the North and South poles which have lower levels of air pressure than other locations on the planet. The combination of these two factors means that a suitably aerodynamic glider can be propelled skywards at tremendous speed. Once the glider reaches the stratosphere, it will have 98% of the Earth’s atmosphere beneath it so maintaining height is one of the biggest challenges. Perlan’s team is confident, however, that their pilots can stay level at around 90,000 feet by navigating and finding various streams to keep them aloft.
The glider itself is something of an engineering marvel. According to the Perlan team’s website, the craft weighs approximately 1800 lbs, with its two-person team inside and has a wingspan of 84 feet. Perlan II has been refined to be as lightweight as possible while keeping enough hull integrity to withstand the near vacuum conditions the craft will be expected to reach. At a height of 90,000 feet, temperatures can be expected to drop to -70 degrees Celsius and such a thin atmosphere would be catastrophic for the passengers if the hull was breached, but the team is confident that they’ve taken all precautions. The craft is equipped with rebreathers should the pilots need them and there are two separate types of parachute for if the pilots needed to eject at extremely high or relatively low altitudes. The craft will also contain several pieces of recording equipment, both to verify its record-breaking status, but also to record scientific data about the atmosphere at that height.
The Perlan team is already looking beyond its expected new record and have big plans for Perlan III. They plan to refine its wings capabilities to be able to reach sonic speeds and reach a height of 100,000 feet.