The more I think about it, that's got to be the reason for the arches (and open ovals), vs the bona-fide hatchways: the openings without any watertight doors really didn't lead off of the "weather deck" (catwalks), but just into semi-protected storage areas - cubbies, or even corridors, under the flight deck. The bona-fide doorways to the gallery, which was not supposed to remain exposed to the (severe) weather, must be the ones with the doors.

The surprising thing - for all of them - remains that their locations appear to be so different on different ships - even within the same type of fit. You'd expect that all the Essexes would have a similar arrangement of internal spaces and equipment - so the access to them would have to be in about the same places - and the same would go for storage of their required tools/fittings, as well.

But it just ocurred to me that the deck-edge was where these arrangements of equipment probably varied the most - particularly the deck-edge guns you mentioned - and particularly with the addition of starboard-side 5" sponsons on the SCB-27s (but also the great variation in 20mms, as well) - this might explain much of the mismatches so far observed on the starboard sides.

I know it sounds geeky, but this topic is becoming more and more interesting to me - not least because these openings, peeking out in key places, really give an Essex carrier the look of an Essex-class carrier.

So, thanks for the input, Donny!

Oh - and one more thing: what the h*ll are you doing up at four in the morning?!!! Go back to SLEEP!

Cheers,

-Matty