You got it! Over to you!
The PT's had their engines mothballed to reduce the risk of fire during transit - this meant that they couldn't fire up the engines to get the compressed air the weapons mounts needed to operate.
They worked around it by cutting the compressed air lines and having one person fire the weapon, another move the mount, while a third acted as a spotter.
The boats were also _really_ close to the Ramapo's weapons and were subject to a pretty severe beating from the back blast.
Also while we're on the subject of the Ramapo - while I was looking for "hints", I found this:
http://hyperphysics.phy-astr.gsu.edu/hbase/watwav.html
112 ft waves - WOW.
John