|Manufacturer||Stabilimento Construzioni Aeronautiche (SCA)|
|First flight||September 1920|
|Status||Destroyed in crash 21 February 1922|
|Primary user||United States Army|
Roma was an Italian semi-rigid airship, originally designated the T-34. It was purchased by the United States from the Italian government for $250,000 in 1921. It served in the US Army until February 21, 1922, when it crashed in Norfolk, Virginia. It was the last hydrogen filled airship used by the US; all future ships were filled with helium.
Design and development
The Roma was designed by Celestino Usuelli, the engineers Eugenio Prassone, Umberto Nobile and Colonel Gaetano Arturo Crocco. It was the first project of the Stabilimento Costruzioni Aeronautiche ("Aeronautical Construction Factory"), as the partnership of Umberto Nobile, Usuelli, Giuseppe Valle and Bennetto Croce was known. The T-34 was designed for trans-Atlantic crossings. It 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 Ansaldos were mounted outside, angled such that the slipstreams would not interfere with each other.
In September 1920 Roma made a trial flight.
After purchase by the US, in March 1921 the Roma flew the 300 miles from Rome to Naples and back carrying the US Ambassador.
After transportation to the US, Roma flew on 15 November 1921 with minor problems.
The Roma crashed in Norfolk, Virginia during test flights on February 21, 1922. The crash was believed to be caused by failure of the Roma's box rudder system, which allowed it to maneuver over tight areas. The ship contacted high voltage lines, and burst into flames. 34 people were killed, 8 were injured, and 3 escaped unharmed. Among the dead was the airship's pilot, Captain Dale Mabry. The event marked the greatest disaster in American aeronautics to that time.
Data from 
- Length: 125 m (410 ft 0 in)
- Diameter: 25 m (82 ft 0 in)
- Volume: 33,810 m3 (1,193,000 ft3)
- Empty weight: 34,500 kg (76,000 lb)
- Useful lift: 19,100 kg (42,000 lb)
- Powerplant: 6 × Liberty L12, 300 kW (400 hp) each
- Maximum speed: 128 km/h (80 mph)
- "The "Roma" Disaster" (pdf), Flight XIV (688), 2 March 1922: 140, retrieved 20 August 2011
- "The New Italian Usuelli Semi-rigid airship" (pdf), Flight XII (614), 30 September 1920: 1044–1045, retrieved 20 August 2011
- Tampa Times, February 22, 1922. Page 1.
- New York Times, February 22, 1922. Page 1.
- Smith, Alfred Emanuel (December 7 1921). "Photo: Trial Flight Of The Dirigible "Roma" At Langley Field, Virginia". The Outlook 129: 554. Retrieved 2009-07-30.
- Smith, Alfred Emanuel; Walton, Francis (March 3 1922). "The Destruction Of The Roma". The Outlook 130: 369–370. Retrieved 2009-07-30.