While the word armāre means to "arm", contextually "armāta" refers to an armed force, which in naval terms would be an armed fleet. AFAIK the second declension of this would would be "armus", which in the nominative plural would be "armī", which is where English gets the word army from. So just as you wouldn't have an "army" of one soldier, so too you can't have an "armada" of just one ship... especially when it's carrying asylum seeking Mini-Cons and not equipped for cosmic naval warfare like say an actual space-worthy fleet of Imperial Star Destroyers.

In any case, the word "Armada" (not armāta) means "a fleet of warships." After all, the word "science" in English means "the systematic knowledge of the physical or material world gained through observation and experimentation," but it comes from the Latin word "scientia" which means to 'know' or 'understand,' thus any form of knowing or understanding is "scientia," but not necessarily "science." (it's national science week this week btw )