It was a sort of barrel-shaped submersible made of wooden staves held together with metal bands like a barrel with only one man aboard. It was in no sense like a modern submarine, whereas the Hunley was. It was unsuccessful in attempts to attack ships, whereas the Hunley was. Other than being a (somewhat) underwater conveyance with similar intended purposes, there really is no comparing the Turtle with the Hunley.
It was still the first air plane.
Little Willie never even made it to the battle field.
It was still the first tank.