I want to know the answer to the following question:
What do heavily laden aircraft sometimes require the assistance from?
All the background I'm provided with is that "The disadvantage of the ski-jump is the penalty it exacts on aircraft size, payload, and fuel load (and thus range); heavily laden aircraft can not launch using a ski-jump because their high loaded weight requires either a longer takeoff roll than is possible on a carrier deck, or assistance from a catapult or JATO rocket.". Is that enough to answer the question?