Yes there should be a ladder in place to access the equipment. Could be a pulldown stairway or site built ladder permanently in place.

I also have a side comment about the ductwork shown in the picture. Here in Houston we have problems with ductwork sweating on the exterior when they are in contact with each other. You may not have the humidity there that we have here and it may not be an issue for you locally.

On hot humid days when you see ductwork like that you should slide your hand between the ducts to see if there is condensation forming between them. Here in Houston the pictured configuration would most likely be dripping water off the ductwork into the attic.