WORLD FIRST Nato military eco friendly UAV surveillance aircraft
NATO unveils it’s new environmentally friendly UAV surveillance aircraft. Zephyr is a series of lightweight solar-powered UAV originally designed and built by the United Kingdom company, QinetiQ.  and is now part of the Airbus High Altitude Pseudo-Satellite (HAPS) programme.
The Zephyr 7 holds the official endurance record for an unmanned aerial vehicle for its flight from 9 July to 23 July 2010, lasting 336 hours and 22 minutes (2 weeks / 14 days). Record claims have been verified by the Fédération Aéronautique Internationale (FAI) for both duration and altitude, at 21,562 meters. It more than doubled the previous endurance record for unmanned flight.
In a 2008 demonstration for the US military, a smaller-scale version of the Zephyr (Zephyr 6) performed beyond the official world record for the longest-duration unmanned flight, however its 82-hour flight at an altitude of 61,000 feet did not set an official record because FAI officials were not involved in the flight.
It is of carbon-fibre construction, and uses sunlight to charge a lithium-sulphur battery during the day, which powers the aircraft at night. The aircraft has been designed for use in observation and communications relay.
The vehicle can circle over a particular area for extended periods. The military uses the vehicle for reconnaissance and communications platforms. Civilian and scientific programmes use it for Earth observation. During the day, Zephyr uses its state-of-the-art solar cells spread across its wings to recharge high-power lithium-sulphur batteries and drive two propellers. At night, the energy stored in the batteries is sufficient to maintain Zephyr in the sky. The lithium sulphur batteries are supplied by Sion, and the first version had a battery capacity of 3kWh.
Zephyr 7 is bigger and requires five individuals to launch, as opposed to three previously. The team runs gently into the wind until it lifts out of their hands. Zephyr 8 is now under development and will be bigger still, with a 28 metre wingspan.
The Zephyr system was sold to EADS Astrium (now named Airbus Defence and Space) in March 2013 where it has successfully re-flown as part of the High Altitude Pseudo-Satellite (HAPS) programme  In 2014 it flew for 11 days in winter, and later near civilian airspace.
The 53 kg Zephyr typically climbs to about 40,000 ft on its first day, and then maintains between 60,000 ft and 40,000 ft thereafter.
Payload: 2.5 kg (5 lb)
Wingspan: 22.5 m (73 ft 10 in)
Loaded weight: 53 kg (116.8 lb)
Powerplant: 2 × 450W Newcastle University custom permanent-magnet synchronous motor, () each
Cruise speed: 30 knots
Service ceiling: exceeds 21 km (70,000 ft)
An aircraft is a machine that is able to fly by gaining support from the air, or, in general, the atmosphere of a planet. It counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines.
The human activity that surrounds aircraft is called aviation. Crewed aircraft are flown by an onboard pilot, but unmanned aerial vehicles may be remotely controlled or self-controlled by onboard computers. Aircraft may be classified by different criteria, such as lift type, aircraft propulsion, usage and others.
Main article: History of aviation
See also: Timeline of aviation
Flying model craft and stories of manned flight go back many centuries, however the first manned ascent – and safe descent – in modern times took place by hot-air balloon in the 18th century. Each of the two World Wars led to great technical advances. Consequently the history of aircraft can be divided into five eras:
Pioneers of flight, from the earliest experiments to 1914.
First World War, 1914 to 1918.
Aviation between the World Wars, 1918 to 1939.
Second World War, 1939 to 1945.
Postwar era, also called the jet age, 1945 to the present day.
Methods of lift
Lighter than air – aerostats
Aerostats use buoyancy to float in the air in much the same way that ships float on the water. They are characterized by one or more large gasbags or canopies, filled with a relatively low-density gas such as helium, hydrogen, or hot air, which is less dense than the surrounding air. When the weight of this is added to the weight of the aircraft structure, it adds up to the same weight as the air that the craft displaces.
Small hot-air balloons called sky lanterns date back to the 3rd century BC, and were only the second type of aircraft to fly, the first being kites.
A balloon was originally any aerostat, while the term airship was used for large, powered aircraft designs – usually fixed-wing – though none had yet been built.