I was looking up some information about ULA's Vulcan rocket, and noticed something odd. There are two configurations, Vulcan 5H2 and 562 that have the same number of boosters, the same size of tanks, but the Heavy configuration has slightly more performance. What is difference between these two?
What is the difference between the Vulcan 562 configuration and the Vulcan 5H2 ("Heavy") configuration?
The Vulcan Centaur Heavy vehicle, flies the upgraded Centaur using RL10CX engines with nozzle extensions.
1$\begingroup$ I've just asked the (potentially naive) question Why nozzle extensions for ULA's Vulcan; why not make them this long in the first place? $\endgroup$– uhohAug 22, 2020 at 13:39