Pretty sure hydraulic catapults were out of service long before I was of age to drive. :P
LOL!
Hydraulic cats were installed on the ASW 27 Charlie aircraft carriers.
I went to WESTPAC in USS Kearsarge (CVS-33) in 1966 and again in 1967/68.
The 27 Charlie attack boats had steam cats.
When the 27 Charlie ASW carriers were retired in the 1970s, hydraulic cats retired with them.
As I said in my earlier post, night hydraulic cat shots were exciting!