03/31/2008. Remarks by Dan Shumaker: "Seen in the markings of W.C.A.T.CO. (West Coast Air Transport Co.), this is one of eight Air Yachts operated by the airline. The aircraft carries the construction number "No.12" on the nose. W.C.A.T.CO.'s fleet of Air Yachts consisted of at least two types, the 3-CT-4 and the 3-CT-8, both ten-seaters.
While the 3-CT-4 was fitted with a Pratt & Whitney Wasp nine-cylinder radial and two Ryan-Siemens nine-cylinder radials (license manufactured Siemens & Halske Sh 12), the 3-CT-8 was fitted with a Pratt & Whitney Hornet nine-cylinder radial (also known as the R-1690) and two Wright J-6 Whirlwind 7 seven-cylinder radials (also known as R-760)."