This question about topside color on US Nukes has been brought up before .. here and in other forums.
A few months ago during a meeting at USSVI in Groton CT I took the opportunity to ask this question to several period SSN Sailors.. Not a single Vet who rode early SSNs could recall "any" boat being painted grey. They were aware of some guppies and one of the few "Tonkin Gulf Spec Op SSBNs" being painted with grey sides and fairwaters.. even the SSN 571 was painted overall black soon out of the yards. ( She was gray originally like a guppie) Most explain the appearence of grey in photos to the nature of the paint used which was more like a "Tar" than a paint and faded fast in operations..But they all said it was possible a nuke was painted grey at some time???? Oh well.
Keep in mind that Nuke Boats spend as much time underwarter as some skimmers hull bottoms do and salt water will do a number on pigments etc.And I believe the Skipjacks may of had Fibreglass sails early on which would also lend to the grey fade color... I will find out..
I have seen this fade effect up close and personal on every boat I rode.
I have also seen this effect on several of the 35MM photos I have in my personal collection of my boats photos.. The fading was most evident on Med and WestPac Boats.
But like most things in this wonderful hobby of ours it's still the builder's artistic license to do as they wish.. I usually used NATO black or even one of the Darker RLM Black/Grey shades or combo of all on my Nuke Boat kits depending on Boat and condition I wish to model her in.
It's funny that we see less of this effect on 688s and newer boats due to the tiles.. The fairwaters seem to fade a little but the tiles stay blacker longer.
Be Well/DBF
Walt