The 63'-footers that were built around the same time ('51-'54) were armed when put into service. The two 94-footers were prototypes, one built by Stephens Brothers shipyard (Stockton, CA) and the other by Detroit Basin shipyard (Detroit, MI). They were armed with M45 quad .50 cal mounts fore and aft for their trials. The prototypes went through testing on their respective coasts, however there were issues with their engineering plant. During this time the helicopter was introduced in the SAR role as well and proved more effective than crash boats. The 94' design was not adopted for production and the two prototypes were transferred to the Navy (around 1956 if I recall correctly) where they were used as small craft, not crash boats. I believe that the Navy disposed of them shortly there after. One was purchased and turned into a yacht.
I grew up in the Detroit area and two years ago was there visiting family and managed to spend some time at the Detroit Historical Society archives going through their Detroit Basin collection. There were ten boxes of various documents, drawings, and business records from Fisher Boat Works and Detroit Basin shipyards and I spent three days sorting, cataloging, and entering the collection into the society's collection database. The collection contains some information regarding the 94-footer R-21A-1251, including the boat's equipment allowance and check list, operator's manual, a small amount of correspondence, and some minor drawings of boat components.
These prototypes were designed by John Hacker and the Mariner's Museum in Newport News houses the John Hacker Collection, including photographs and a number of drawings for the 94-footer. The drawings are design drawings, though, not production drawings, and there are some notable differences between the drawings in the collection and the photographic evidence of the prototypes as constructed.
The National Archives II in College Park, MD has several photographs of R-21A-1251during trials.
Matt
"I can imagine no more rewarding a career. And any man who may be asked in this century what he did to make his life worthwhile, I think can respond with a good deal of pride and satisfaction: 'I served in the United States Navy.'"
President John F. Kennedy, 1 August 1963, in Bancroft Hall at the U. S. Naval Academy.