Troops

As you might imagine, the discussion under this comic is full of "Ha ha, in the navy, you don't have to think!" But there's always someone who knows more. 

There's a flaw in the question. Cavalry are defined by mounted combat, not just travel. A Dragoon is a type of "mounted infantry"; they have a horse they can ride to the battlefield, instead of marching, so there's less downtime between arrival and being ready to fight. But their horses aren't comba-trained and not suited to cavalry use; they're still infantry because they do the actual fighting on foot. Also, cavalry doesn't necessarily need to ride a horse, specifically. Elephants have been used as cavalry. And I'm about... 85% certain Russia uses bears as cavalry. Also, there are things like chariots and war wagons which are pulled by horses; but you ride the vehicle, not the horse, itself.

Different contextual applications of the term "Cavalry". Specifically, modern vehicles referred to as "Cavalry" are actually more properly called Mechanized Cavalry or Armored Cavalry to indicate their vehicular nature. There's also Mechanized Infantry which fulfills the role of the Dragoon, using a vehicle to carry troops to a location, but the vehicle, itself, is not truly capable of a sustained or devoted fight. Don't go up vs tanks in a Humvee.

The Air Cav, like other Cavalry divisions, is specifically geared around armored helicopters which carry out reconnaissance and some troop transport. Also gunships. But in general, calling a Mechanized unit "Cavalry" implies they're using the vehicle as a designated combat platform, just as traditional Cavalry fought from horseback.

But they are horses. In the navy. This comic is from Bonus Context.  (via reddit)