The tube closed at one end used to fire aerial devices is known as what?

The term used to describe a tube that is closed at one end and designed to fire aerial devices is "mortar." Mortars are specialized containers that can withstand the pressure and heat generated when an aerial shell is ignited and launched. They feature a closed bottom to contain the propellant gases and allow for a controlled launch of fireworks into the sky. The design of mortars is critical to ensuring safety during fireworks displays, as they are constructed to minimize the risk of unwanted premature discharges and to direct the fireworks upwards correctly.

In contrast, the other terms like "rod," "launcher," and "tube" are not specific enough or do not refer specifically to the closed-end tube used in aerial fireworks. While they may describe related equipment in the broader context of fireworks setups, they do not uniquely identify the function and construction that a mortar provides. Thus, understanding the specific terminology is essential for grasping the proper safety and operational aspects associated with fireworks displays as outlined in NFPA 1123.