Airlander 10, the world’s largest aircraft at 302 feet, flew its second test flight Wednesday. The part-plane, part-ship, referred to as an airship, flew the scheduled 100 minutes before it nosedived into the ground as it came in to land.

In a statement, Hybrid Air Vehicles — the British company behind the 25 million pound ($33 million) airship — said “the Airlander experienced a heavy landing and the front of the flight deck has sustained some damage which is currently being assessed. Both pilots and the ground crew are safe and well and the aircraft is secured and stable at its normal mooring location.”

The BBC cited a witness who said a line hanging from the airship hit a pole a short distance before its landing, but a company spokesman denied the claim. The United Kingdom’s Air Accidents Investigation Branch is also examining the crash.

The Airlander 10 made its first test flight a week ago, on Aug. 17, from the same airfield north of London. According to Hybrid Air Vehicles, the “hyper-efficient aircraft” — which has also been nicknamed the “flying bum” for its shape — “can stay airborne for up to five days at a time if manned, and for over 2 weeks unmanned.”

Airlander10 The Hybrid Air Vehicles HAV 304 Airlander 10 hybrid airship is seen in the air on its maiden flight at Cardington Airfield near Bedford, north of London, Aug. 17, 2016. Photo: JUSTIN TALLIS/AFP/Getty Images