QinetiQ’s Zephyr solar powered unmanned aircraft demonstrates perpetual flight
By Mike Hanlon
July 16, 2010
Zephyr, QinetiQ’s solar-powered, high-altitude long-endurance (HALE), Unmanned Air System (UAS) is currently in the air and setting a landmark unmanned flight duration record by demonstrating what is essentially perpetual flight. The official world record for the longest unmanned flight is 30 hours 24 minutes set by Northrop Grumman's RQ-4A Global Hawk in 2001. A previous smaller relative of the current Zephyr holds the unofficial record of 82 hours but this time QinetiQ has FIA officials on hand and has been flying the new 22.5m wingspan plane for the past week, and is closing on the 200 hour mark with another week (168 hours) planned. It needs to land safely to claim the record, but the feat has already demonstrated that the era of low-cost, persistent aerial surveillance has begun.
Zephyr is currently flying high above the clouds over the US Army's Yuma Proving Ground in Arizona, on the way to becoming the world's first truly eternal plane.
The benefits of such capability are many, with the most obvious being persistent surveillance over months rather than days. Some other logical applications include earth observation and communications relay in support of a range of defence, security and commercial requirements.
The current Zephyr aircraft is a genuine breakthrough design, drawing on the latest technology and represents a massive leap forward in engineering excellence incorporating an entirely new wing design.
“The team has worked tirelessly over the past few years, making truly significant leaps forward in overall design and construction - and to see it successfully soar into the sky was fantastic,” explained Jon Saltmarsh, Zephyr Programme Director. “By being able to remain over a location for weeks or months at a time, it can usefully deliver a host of practical and more affordable solutions to both civil and military customers.”
Launched by hand, the aircraft flies by day on solar power delivered by amorphous silicon solar arrays no thicker than sheets of paper that cover the aircraft's wings. These are also used to recharge the lithium-sulphur batteries, supplied by Sion Power Inc, which are used to power the aircraft by night. Together they provide an extremely high power to weight ratio on a continuous day/night cycle, thereby delivering persistent on-station capabilities.
Around 50% larger than the previous Zephyr, technical changes now mean it has a 22.5m wingspan to accommodate more batteries that are combined with a totally new integrated power management system. The entirely new aerodynamic shape and high “T” tail also contribute to reduce drag and improve performance. The payload capacity will meet a number of key surveillance and communication requirements already demonstrated by Zephyr over the past three years. Zephyr’s ultra-lightweight carbon-fibre design also means it weighs in at just over 50Kg.
Unlike conventional manned or unmanned aircraft now being operated, Zephyr does not need to return to base at regular intervals for re-fuelling or servicing which also helps minimise the logistical supply chain and extend its operational capability.
The QinetiQ Zephyr will be show-cased at the Farnborough International Airshow.