Sikorsky S-38 Flying Boat Amphibian
With as many as 12 seats, 900 hp, and amphibious capabilities, the S-38 was a very useful airplane. Used by both corporate operators and airlines, the airplane proved itself as a long term airliner in several parts of the world. With its retractable landing gear, the airplane could be taxied in and out of the water, thus eliminating the need to load passengers at sea and also eliminating the need for a runway at either end of the trip.
The airplane was ideal for inter-island work; four were used for many years in Hawaii. Johnson's Wax also used an S-38 as an executive airplane, and it proved itself very useful in a South American exploration flight in search of Carnauba trees.
The company recently commissioned a replica of this airplane and reenacted the trip to South America. There was a single-engine version of this basic design, the S-39, which was also a very successful airplane for Sikorsky.
This is the Sikorsky S-38 model that won the FG Modeling Madness (FGMM) 2010 best in class prize.
I love this design. I copied the S-38 at 1:100 (wingspan 9 inches) onto the back white side of Red River Silver paper, traced over all the ribs, windows and hatch lines with a ball point pen to bring them into relief, and then built it silver side out. The struts are stiffened by folding around basswood strips. The engine cylinders and wheels are built with the printed/white side out, for contrast. -Robert
Chip, It's just great to see these Sikorsky's up on fg, I know its been a lot of work for everybody, Dave, yourself, Mauri, but I think it is so very cool to have the ability to model these marvelous birds. Good job guys!!!! glenv (the designer)
Am in the middle of the S38 build - another remarkable model! I took the liberty of contacting Johnson Wax, to let them know that the model existed. They are more than a little in love with the S38. Not only did they build a replica and fly it to Brazil, they just went to Indonesia and found the original, that sank in 1938. I hope they will finance you to make a "Spirit of Carnauba" version of the plane. Robert Tauxe, Atlanta
I'm traveling, so I can't send any photos until I get home, but there are still issues with the S-38. First, did you notice that the photo on the web site seems to be missing a couple of struts. Like the rear struts on the right wing? I looked and looked, but I swear that they aren't there. Second, either the long wing struts or the marks for where they go on the top wing are wrong. If they are made the length they are printed, they are way short of the marks. I think the marks are in the wrong place.
Finally, the S-38 is a real bear to put together. I think I finally got it right, and I took some close ups of the strut arrangements that you might post. The drawings and instructions do not make it clear where all of the struts go. The interleaves engine mount struts and cabanes are absolutely weird. Also, the mounts for the floats on the lower wing bear no relationship to the three views. They look like upside down v's on the assembly drawing, but they look like parallel verticals on the drawing. They certainly don't match the fiduciary marks on the floats.
I improvised. There is no way to put this
thing together without some kind of jigs. I built the top
wing, booms, engines, and tail all together. The best way
I found to mount the wing is to use the strut above the
center of the fuselage and then built the triangle that
holds the booms to the fuselage. This tripod is a sort of
stable configuration for mounting the rest of the struts.
But there's still a lot of fiddling and weaving necessary
to get the remaining struts in place. As usual, the booms
are solid, laminated from many sheets of paper, and all
of the struts are at least four layers thick.
The S-38 and S-39 are absolutely beautiful models. I've built all of your airplanes (several more than once), and these guys are off the charts in skill level required. Even worse than the Focke-Angels helicopter.
I wonder if some of the discrepancies I've found are a result of your handing off to your apprentices.
Dave Finkleman (see below)
Not the most elegant flying boat, being variously
described as the “Ugly Duckling”, "Flying tadpole”,
and “ A collection of airplane parts”, the S-38 was
the first commercial success for the fledging Sikorsky Corporation.
Being amphibian, the design was very versatile. Pan American operated
the S-38 primarily around the Caribbean.
The original S-38 came from the fertile mind of Igor Sikorsky. More than 100 were built and sold. Its success helped bankroll the Russian engineer for his most challenging design yet: another type of aircraft called....wait for it...a helicopter.
Imagine this wonderfully sleek, 1930s-era speedboat, handcrafted in expensive hardwoods and lavishly decked out in cabin upholstery, curtains and appointments befitting a classy yacht. Now rig up a couple of wings and slap on two 450-hp Pratt & Whitney R-985 Wasp Junior engines, and you've got the quintessential Terry and the Pirates-era amphibian: the Sikorsky S-38 Flying Boat. The handcrafted stringers and elegant lines of the "hull" favor the lines of a classic speedboat more than an airplane. It's only with the wings and the addition of two Pratt & Whitney engines that the craft's true mission becomes evident.
Below are a few progress views Glen sent in as he was figuring out the design
Specifications for the Sikorsky S-38
Capacity: 10 passengers
Length: 40 ft 3 in
Wingspan: 71 ft 8 in
Height: 13 ft 10 in
Wing area: 720 ft²
Empty weight: 6,000 lb
Loaded weight: 10,480 lb
Powerplant: 2× Pratt & Whitney
R-1340 Wasp 9-cylinder air-cooled
radial engines, 400 hp each
Maximum speed: 120 mph
Range: 750 miles
Service ceiling: 16,000 ft
Rate of climb: 750 ft/min
Wing loading: 14.5 lb/ft²
Power/mass: 0.08 hp/lb
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