Monoplane flying boat, central hull with stabilising floats, fitted with 12 engines in tandem pairs on 6 nacelles, all-metal construction.

In 1931, a Do.X flying boat was taken into service by the Regia Aeronautica and, In the same year, he undertook a propaganda cruise along the Italian coast. In 1934, an accident led to his decommissioning.

In 1932 another Do.X flying boat was taken into service and participated in naval air manoeuvres in August of the same year.Subsequently, he conducted instructional cruises for attendees of the Army War College and the Naval War College.

It remained in service until August 1934 and was then, like its predecessor, laid up.