The R101 Airship was a newly-built British airship that crashed on October 5, 1930 in France with 48 casualties.

The creation of the R101 was the result of a competition between the private company of Vickers and the British government's Air Ministry. Vickers was to produce the R100 airship and the Air ministry, the R101. Two of the engineers working for Vickers were Barnes Wallis the designer and, as chief calculator, Nevil Shute Norway, a future author who later wrote about the case.

The building of the R101 began in 1926 at the Royal Airship Works in Cardington near Bedford, England. Due to a failed attempt to create hydrogen-using engines and several other new design concepts, the project's end was delayed from 1927 to 1929. The R101 was meant to have a useful lift of 60 tons but ended up having only 35. It had two decks and a dining room for 60 people and it was fitted with heavy diesel engines. Its gas bag valves may have also been defective, which led to the continual decrease of lift in flight.

The stability of the R101 was in doubt. During its flight at the Hendon air show in 1930, it almost plunged to the ground and kept falling into a dive during the return flight. Its gas bags also developed numerous leaks. Despite this, it was given a Certificate of Airworthiness. Engineers added another gas bag, reversing propellers and replaced the outer cover. After that the ship's volume totalled 5.5 million cubic feet (156,000 m³) and it was 777 ft (237 m) long.

The Air Ministry pressured the engineers to finish the project. The final trial flight of the R101 was originally scheduled on September 26, 1930 but an unfavourable wind delayed it until October 1. It returned to Cardington after a flight of 17 hours.

The R101 departed on October 4 at 6:24 PM for its intended destination in India via a refuelling stop at Ismalia in Egypt under the command of flight lieutenant Carmichael Irvin. Passengers included Lord Christopher Thomson, Secretary of State for Air, and Sir Sefton Brancker , Director of Civil Aviation. It had to drop 5 tons of water ballast to lift off.

Over France the R101 encountered gusting wind and crashed into a hillside near Beauvais, north of Paris. 46 of its 54 passengers and crew were killed. Two men who escaped the crash died later in a hospital bringing the total to 48 dead. According to survivors, the top layers of the outer cover and some of the forward gas bags had been torn in the wind thus causing a loss of the flammable lifting gas hydrogen which was ignited by the hot engine exhausts and electrical sparking from torn wiring.

The R101 spelled the end of the British attempt to create lighter-than-air aircraft. Its competition, the R100, despite a more successful development program, and a safe transatlantic trial flight, was mothballed immediately after the R101's crash. It was sold for scrap in 1931.