I took a look at the photo in page 253 of "The Fighting Lady" and I must say that I�m not completelly convinced that it is a proof that Yorktown was already painted MS21 at that time (March 45). I can see why you think that way, because the starboard 40mm sponsoons are all the same shade, as well as the 5�gun mounts and the island. But if you take a look at the previous scheme (MS32/10A ) you�ll notice that all the area covered by this picture was painted with the same colour (5-L Light Gray). The only exception was the 40mm sponsoon closer to the camera, which in the MS32/10A paint diagram, was supposed to be "split" between two colours (5-O Ocean Gray and 5-L Light Gray). And there lies the doubt...in this photo, that sponsoon is only painted in one colour. Now, is that a proof that she was already in MS21 or that the paint job done on the MS32/10A was not 100% correct ???
Also, the book I mentioned earlier is named "Aircraft Carrier" and was written by J.Bryan, III. Its a kind of diary that he kept while he was onboard Yorktown (30Jan45 - 30Apr45), and on page 63 he wrote:
March, 6th. Ulithi,Guam...The whole ship was painted, scrubbed and shined...
So, no doubt that Yorktown did get a paint job while at Ulithi. MS32 "overhaul" or a brand new MS21 ??? The author doesn�t mention...

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PS - Would Mr. Keith be kind enough to let us know, why does he thinks that Yorktown got her MS21 scheme only in July ?