The ladders you may see on “Engines” are few in number and generally not very long. The ladders on trucks can be 50 feet long or more each. This does not include the hydraulic operated, apparatus mounted, “aerial devices”. These are the giant ladders or “Snorkels” seen on some apparatus. They can be “articulating boom” (Snorkel) or large extension ladders with or without platforms on the end. While an engine may carry 30 - 40 feet of ladders, a truck may carry hundreds of feet of hand deployed "ground ladders" plus a 100ft or more aerial device.

http://www.fireserviceinfo.com/apparatus.html

والله أعلم