Airlander 10: World's longest aircraft hits highest altitude

The world's longest aircraft has reached the highest altitude it has attained so far.

Airlander 10 ascended to 3,500ft (1,067m) on its fourth test flight.

Based in Cardington, it is a cross between a plane and an airship and cost £25m.

Developer Hybrid Air Vehicles believes it could be the future of air travel.