Opinion and Answer IX Tank Engines: The different styles

Tank Engine: Real Life Thomas version

Scenario: You look at one tank engine one day and then the next day, you are looking at a tank engine but its different than the tank engine you saw the day before and you wonder whats the difference between the two tank engine. 

Well here is the answer for you but first lets look at the definition of tank engine. 

A tank engine is known to have a small bunker with water tanks being on the locomotive instead of being in a tender.

Now lets turn to the different styles of the tank engines. The different styles are based on the water tanks that are built onto the steam locomotive.

There are different types/styles/forms of the water tanks that are used on the small tank engines: 

1. Side 

 The tanks are mounted on the sides of the boiler and extended down to the footplates. Hence why  there is a "T" when using the whytle N=notation (i.e. Thomas the tank engine from Thomas and Friends)

2. Saddle

Mounted over the boiler like a saddle. Hence the "ST" in the whytle N=notation (i.e. Percy the small Engine) 

3. Pannier

The tanks are mounted on the side but don't go down to the footplate. These use "PT" in the whytle notation. (i.e. Duck the great western engine from Thomas and Friends)

4.Well: 

The tanks are mounted underneath the locomotive; these are mostly used only on very small engines such as 0-4-0WT locomotives. These are referred to as "WT" when using the Whyte notation. (i.e. Sonny from Thomas and Friends)

5. Fireless: 

Which is a large, circular tank used for housing boiled and pressurized water heated to have a tank engine travel at slow speeds around industrial areas without creating smoke and sparks from coal-powered fireboxes.

The last few words, I'll say about the tank engines are that they are great for the preservation/heritage railroads across the world.