Mikeym_us:
Because a 30-40ft swell would hardly phase a carrier.
It's not the size of the swell, it's what causes the swell.
Round numbers, the side area of a CVN is about 900 x 35, or over 31,000 square feet of area for winds to push against.
Using q = 0.00256*V² A 30 mph wind (26 kts) exerts 2.304 psf, or about 71,000 pounds over that 31,000 sf, which is enough to impart motion.
30 mph is only Beaufort 6, 10'/3m waves.
But, the other thing to remember is that, as a ship rolls, those antennae are along way out around the axis of rotation, bringing the tips closer to rising wave tops. Add in the flex in the antenna structure, it would be easy enough to roll them into a moderate sea, and seawater has an annoying habit of keeping things like that. Which gets the sparkies all cranky carrying away either send or receive conductors. The hinge mechanisms do not take kindly to unexpected lateral movements, either.
A CVN is a huge object; but oceans are far far far larger, and have been smugly bemused by the vanities of we mere humans.