Roma

Roma was an Italian-built semi-rigid airship, designated by its designer as the Model T-34. Purchased by the United States from the Italian government in 1921, Roma was operated by the United States Army Air Service from November 1921 to February 21, 1922, when it crashed in Norfolk, Virginia, killing 34 people aboard, with 9 survivors. As a result of this accident, Roma was the last hydrogen inflated airship flown by the US military; all subsequent airships were inflated with helium. Design and development The Roma was designed by , the engineers Eugenio Prassone, Umberto Nobile and Colonel Gaetano Crocco. Designated and advertised as the Model T-34, it was the first project of the Stabilimento Costruzioni Aeronautiche ("Aeronautical Construction Factory"), for the partnership of Nobile, Usuelli, Croce and Giuseppe Valle. The T-34 was designed for trans-Atlantic crossings carrying up to 100 passengers, though initially fitted for 25. When constructed, Roma was the largest semi-rigid airship in the world. As a semi-rigid design it was built about a rigid keel - though the keel was partially articulated to allow some flexibility. The passenger spaces and control cabin were within the keel. The engines, 400 hp Ansaldo 4E-2940 V-12s, were mounted outside, angled such that the slipstreams would not interfere with each other.