Zephyr Ultra-Long Endurance UAVs

Zephyr, and NAWCAD

In May 2009, DARPA informed DID that this is not their award, adding that their Vulture program’s Phase 2 contract wasn’t expected until summer 2009 or so. Instead, the NAWCAD contract award marks the 2nd phase of a Joint Capability Technology Demonstration (JCTD) program jointly sponsored by the US OSD DDRE and the United Kingdom’s Ministry of Defence. Testing will include evaluating potential payloads, as well as advancing the concept of operations for operating long endurance persistent aircraft in excess of 5 days.

The program has achieved that goal, and more. As part of this effort, Zephyr’s wingspan has been lengthened to 22.5m/ 73′ 10″, and the wing shape and aerodynamics have been redesigned to lower drag further. The team added batteries, and a totally new integrated power management system. Zephyr flies by day on power from Uni-Solar’s amorphous silicon solar arrays no thicker than sheets of paper. These are also used to recharge Sion Power Inc.’s lithium-sulphur batteries, which power the aircraft at night. The entire UAV is easy to transport in a standard road transport container, and is actually hand-launched by a small team. Despite its size, Zephyr’s carbon fiber construction means that it weighs just 50 kg/ 110 pounds.

While DARPA programs are necessarily long term affairs, the redesigned Zephyr UAV offers near-term value. Conflicts need persistent surveillance with a wide field of view, and a UAV that has low support costs or infrastructure needs, is easily transported in other aircraft, and can stay in the air for 14 days or more, would have its own niche.

Zephyr would offer very long-endurance surveillance that can be flown in on jet transports, unlike a blimp. It also offers far better endurance and lower fuel costs than other UAV options. That’s especially valuable in roles like communications relay, which is important in harsh terrain like Afghanistan that routinely breaks line-of-sight, and will have growing value on our bandwidth-constrained battlefields.

In addition to the obvious defence and security applications, QinetiQ envisions commercial uses include environmental research, monitoring crops and pollution, providing tactical intelligence over disaster zones or forest fires, and delivering mobile communications capabilities in remote areas. Until UAVs can be used in civil airspace, however, and the payloads that let them do so are light enough, Zephyr’s potential uses will remain military.

Contracts & Key Events

2018

October 11/18: Zephyr eyed by US Army The US Army Futures Command is interested in buying Airbus’ Zephyr S HAPS system. The new group is the Army’s fourth command and is tasked with driving the service into the future to achieve clear overmatch in future conflicts. The command wants to use the high-altitude pseudo-satellite for a variety of missions, including as military, security and civil missions and acting as a communication hub. The Zephyr is built out of carbon fibre composite materials and is solar powered. The drone set the world record for flight endurance in July after staying aloft using solar cells for 25 days 23h 57min. Willie Nelson, the Futures Command’s director, told Flight Global “I think they are an incredible capability that we should continue to invest [science and technology] dollars into research and development”. The UK has currently three Zephyrs on order. They will provide British troops with battlefield intelligence and surveillance. The US Army currently has no funded program to acquire high-altitude UAVs.

2009 – 2016

February 5/16: The UK plans to buy two unmanned solar-powered aircraft, known as Zephyrs, which are capable of carrying small payloads that might consist of reconnaissance cameras or communications equipment. The Zephyrs hold the absolute endurance record for un-refuelled aeroplanes staying up for 336 hours, 22 minutes and eight seconds. Developed in the UK by QinetiQ, the technology has been recently bought and marketed by Airbus with the MoD’s vote of confidence expected to lead to an increase in sales. High altitude, solar powered planes have often been used for civilian purposes by companies like Google and Facebook to deliver broadband to locations that lack fixed-line connections.

July 23/10: Zephyr successfully lands after 14 days (336 hours and 21 minutes, launched July 9/10) flying over Yuma Proving Grounds, AZ and is now awaiting official confirmation of its world record status. If FAI confirms the feat as expected, Zephyr will have broken both the UAV and manned time aloft records. The current title holder is Rutan’s manned Voyager at 216 hours, 3 minutes and 44 seconds (9 days), set in December 1986. QinetiQ’s chief designer, Chris Kelleher said:

“The brand-new ‘production ready’ Zephyr airframe incorporates totally new approaches to aerodynamics, structures, propulsion, avionics, flight controls, power system management, thermal control, ground control station design and payload, as well as overall operating processes… We’ve also had to design for temperatures of around plus 40ºC on the ground to below minus 75ºC at altitude, ever changing weather systems including storms and high winds – and Zephyr took them all in its stride. It is a truly fantastic achievement.”

July 16/10: QinetiQ announces that Zephyr is breaking UAV records on its current endurance flight. It has already passed the 7 day / 168 hour mark, doubling its own previous record of 82 hours, 37 minutes set in 2008, and crushing the current official world record of 30 hours 24 minutes set by Northrop Grumman’s RQ-4A Global Hawk on March 22/01.

Longer Global Hawk flights have been held since, but record certification requires the presence and oversight of the Federation Aeronautique Internationale (FAI). At QinetiQ’s invitation and with customer permission, an FAI Official has been monitoring progress at the Yuma Proving Ground. Zephyr’s world records will not become official until the aircraft is safely back on the ground. QinetiQ.

Nov 23/09: QinetiQ’s Zephyr High-Altitude Long-Endurance unmanned aerial system (HALE UAS) resumes flight and payload evaluations in Yuma, AZ, as a joint US/UK Zephyr team undertakes the first operation of the system with a US flight crew. This test sequence, jointly sponsored by Britain’s Ministry of Defence and the USA’s OSD DDRE, focused on evaluating potential payloads as well as advancing the concept of operations for UAV flights longer than 5 days.

This was the first deliverable following the $44.8 million enabling contract awarded in May 2009 to QinetiQ North America for operational training in the US, accelerated development, in-theatre evaluation, and possible transition to production of Zephyr and its associated ground station. QinetiQ.

Additional Readings

• QinetiQ – High altitude long endurance UAV – Zephyr