by Rajay » Sat Sep 27, 2014 8:54 pm
In checking whatever info there was in Fred Kight's new book on Grumman Amphibians, first off I'm more & more disappointed with all of the obvious mistakes that I keep finding there, so I don't know what info I can trust that is not already known to me in its correct form separately from the book.
For example, the book more often than not improperly identifies the Lycoming engines used in the McKinnon Super Widgeon conversions as the models GSO-435-C2B (260 hp) and GSO-480-B1D (270 hp) when of course none of those engines were supercharged or had a corresponding "S" in their model designations. For the most part, the actually supercharged GSO-480 series engines, such as the GSO-480-B2D6 engines that McKinnon used on his 4-engine G-21C Goose conversion, were rated much higher at 340 hp.
Similarly, in the book, the Franklin / Gander IO-470 engine conversion is identified as STC no. SA152SO, but that too is apparently incorrect because according to the official documentation from the FAA archives in OK City that I havein my possession, the correct STC numbers are SA81SO for the installation of the IO-470 engines on the Widgeon and SE152SO to modify how the fuel injection servo is mounted on the engine itself. The "SA" code signifies an STC for modifying an Airframe and the "SE" code one for modifying an Engine - quite logically so.
So too, when the book noted that the J. Ray McDermott IO-470 engine conversion for the Widgeon was STC SA2-284, I don't know if I can trust that. I think that I'll require independent corroboration. However, I could find no record of such an STC in the current FAA database, including in terms of "surrendered" STCs, so if that number is correct and it did exist way back when, I suspect as Bill suggested that it was surrendered a very long time ago.
The search for the Widgeon X-files continues...the truth is out there!