Image from the Italian-built semi-rigid airship Roma, overflying the bombing of the unmanned ex-German Wiesbaden-class scout cruiser SMS Frankfurt off Cape Henry, Virginia, on 18 July 1921. Note the U.S. Navy Felixstowe F5L flying boats overhead and the white targets painted on the deck of the former Kaiser’s former warship.
The big seaplanes, with a 103-foot wingspan, could carry up to 900 pounds of bombs while self-defense was provided by four Lewis guns. However, even with their two big Liberty L12 engines, it could only make about 70 knots at full rpms.
As for Roma, the unusual lighter-than-air aircraft purchased by the U.S. Army for $184,000 from the Italian government just three months prior to the above images. Over-powered by six Liberty engines (which replaced the four original Ansaldo engines), the big 410-foot airship could actually outrun the F5L in terms of speed, not to mention range.
However, being hydrogen-filled, Roma was a flying bomb and burst into flames when brushing against powerlines outside of Norfolk on 21 February 1922, killing 34 aboard, and was the worst U.S. aviation accident on record at the time. Following the incident, the U.S. military went with helium for LTA vehicles moving forward.