World's largest aircraft 'Airlander 10' revealed
The world's largest aircraft has been unveiled for the first time since being fully assembled in the UK.
The 302ft (92m) long Airlander 10 - part plane, part airship - was floated in a First World War hangar in Bedfordshire.
Photographers struggled to capture the whole length of the aircraft, which is around 50ft (15m) longer than the biggest passenger jets.
It was first developed for the US government as a long-endurance surveillance aircraft but it fell foul of defence cutbacks.
British firm Hybrid Air Vehicles (HAV) launched a campaign to return the Airlander 10 to the skies in May 2015.
It will now carry out ground testing before 200 hours of test flights begin later this year.
The huge aircraft will be able to stay airborne for around five days during manned flights.
HAV claim it could be used for a variety of functions such as surveillance, communications, delivering aid and even passenger travel.
Speaking at the launch event in Cardington, Bedfordshire, chief test pilot David Burns, who last flew the aircraft in 2012, said: "It's very pleasant to fly. From the flight deck you have a lovely view.
"It allows you to have a good look around because generally the flying is fairly low so there's plenty to see.
"For the people on board and the people down below it's going to look quite a sight.
"You're talking about 300 feet long. There's nothing that size at the moment."
The Airlander 10, which uses helium to become airborne, can travel at a speed of 92mph (148km/h).
It is 143ft (44m) wide and 85ft (26m) high.
Professor Chris Atkin, who will become president of the Royal Aeronautical Society in May, described the project as "absolutely fantastic".
He told the Press Association: "It's a new slant on a well-established idea with very clever use of technology."
After sitting in the cockpit of a flight simulator developed for Airlander 10, Mr Atkin predicted that the aircraft could be used by passengers on pleasure flights and to get to locations that are hard to reach.
"I can imagine this competing with cruise ships over really interesting environments," he said.
"The view is quite extraordinary. It's a very relaxed experience. It will be a very quiet and stable vehicle to travel in."
It is hoped that the Airlander 50 will eventually be developed, which would be able to transport 50 tonnes of freight.
Helium is a non-renewable resource, but Catherine Dewar of industrial gas supplier BOC said there are "many untapped sources" around the world.
She continued: "There is enough helium for something as bespoke as this.
"It's never going to be on a huge mass market so - for the scale you would expect to see this - there is plenty of helium to support it."