and this is why I brought it in

During World War I, the M.5 was operated by five Italian maritime patrol squadrons as a fighter and convoy escort, and some were embarked on the Regia Marina seaplane carrier Giuseppe Miraglia. Towards the end of World War I, M.5 aircraft were flown by both United States Navy and United States Marine Corps airmen. For his actions while flying an M.5 over the Adriatic Sea off the coast of Austria-Hungary on 21 August 1918, U.S. Navy Ensign Charles Hammann, an enlisted pilot at the time, received the first Medal of Honor awarded to a United States naval aviator.

The citation

For extraordinary heroism as a pilot of a seaplane on 21 August 1918, when with three other planes Ens. Hammann took part in a patrol and attacked a superior force of enemy land planes. In the course of the engagement which followed, the plane of Ens. George M. Ludlow was shot down and fell in the water five miles off Pola. Ens. Hammann immediately dived down and landed on the water close alongside the disabled machine, where he took Ludlow on board. Although his machine was not designed for the double load to which it was subjected, and although there was danger of attack by Austrian planes, he made his way to Porto Corsini.

next?

...and now for something completely different.

Although mostly civilian, I think it was used for naval patrol or Coastguard.