I recently came across a reference to the many Swiss watches that were employed by the US Navy. The US Naval Observatory at Washington held open trials and those that scored well were purchased for military use. It appears they were not as jingoistic as many other countries! It was mentioned that Vacheron & Constantin broke the record with top score in the trials of October 1921 to March 1922. In fact, V&C took the top three places in the category of Torpedo Boat Watch .
By way of explanation; the ship's chronometer was the main watch on large ships, carefully stored and protected from sudden shocks in a large gimbaled wooden box. These proved to be completely unsuitable to the new class of small, fast torpedo boats that were developed at the turn of the 20th century. For these, the portable lever deck watches (chronometre de bord or HS2 under the British system) were pressed into service, while being subjected to the same rigorous timing standards as the big marine chronometers. They were still required to perform the same navigation duties, after all. And it was found they did very well indeed.
The 1922 Annual Report of the United States Naval Observatory provides confirmation of this amazing feat:
Here we find that V&C Nr. 361624 took first place with some outstanding results. This watch had a very accomplished history; already having achieved Bulletins in trials at Geneva for 1915, 18 and 19. It was also submitted for trials at Washington again in 1924, following it's stellar performance here in 1921-22.
2nd place was captured by 374604. This watch followed a slightly different route, with it's first Bulletin achieved in 1917 at Geneva, then Kew the following year, and finally arriving at Washington for these trials.
3rd place nr. 379510 debuted in Geneva in 1918 and again in 1920, then Kew for 1920-21, before arriving at the US Naval Observatory. I just happened to have a copy of the Kew results as published by this Swiss journal, 22nd down the list. Note the differing references to integral and Guillaume balances.