article on the Ryan S-C appeared in the July 1968 edition of American
Aircraft Modeler. The S-C was unique in many ways, the least of
which was its monocoque construction throughout - wing, tail surfaces,
and fuselage. Its production, certain to be a hit, was abruptly
halted after just 10 production models due to WWII requiring the
factory be used for military aircraft.
"Designed as an up-market
version of the Ryan S-T trainer, the S-C was a low-wing cantilever
monoplane with a fixed tailwheel landing gear. The prototype first
flew in 1937 and had a nose-mounted 150 hp Menasco inline piston
engine. Production aircraft were fitted with a 145 hp Warner Super
Scarab radial engine. With the company's involvement in producing
trainer aircraft for the United States military, the S-C was not
seriously marketed and only 12 production aircraft were built. One
example was impressed into service with the United States Army Air
Force and was designated the L-10." -
A trend setter that looks as modern today as it did 30 years ago.
PAUL R. MATT
Photos / Ryan and Historical Aviation Album
was a beautiful ship, just as beautiful and easy to fly, too - you
knew it was a trend setter, and those few that are still flying
look just as modern and at home today as they did 30 years ago."
So stated a pilot recently who had considerable time on the Ryan
S-C shortly before WW II and for a couple of years after. To this
we can add that the S-C was more than a trend setter in its class;
it was the first truly successful private plane to pioneer the all-metal,
low-wing, enclosed-cabin concept. A plane that had everything going
for it if a nasty war had not intervened and halted production.
The 145-hp Warner-powered Ryan S-C prototype flies over San
Diego Bay shortly after conversion from in-lined configuration.
Warner 145-hp radial proved more reliable, rugged, easier to
maintain. Only 12 S-CW's built before military contracts interfered.
Access to the Warner engine was simplified by an automobile
hood type cowling, shown in opened position here on the prototype
Test pilot John Fornasero runs up the engine for first flight
in early 1937. The design called for 95- to 150-hp Menasco engines.
T. Claude Ryan envisioned the S-C (Sport Cabin) in 1936. Later,
in a resume about its development, he expressed his hopes, intentions
"The plane was planned from the first
preliminary drawing as a production job," he stated. "We wanted
to develop a type of construction so simple and so practical that
it would lend itself to efficient manufacture in much larger quantities
than had been customary in the past.
have for years toyed with the idea of airplanes stamped all at once
in one huge press, or poured out of some synthetic material in a
single molding operation, or somehow fabricated so as to avoid the
tedious hand fitting of limitless numbers of small parts. We believe
that in the development of the S-C we approached this ideal of the
"It is a much more difficult assignment
to simplify a structure than to 'complexify' it," he went on, "We
feel it (the S-C) is the most simply manufactured metal airplane
and the most adaptable of any yet developed to an efficient production
Ryan achieved the classic S-C through two years
of extensive study, experiment and ingenuity. Every part, with few
exceptions, was either a flat sheet or a drop-hammer stamping. Flat
sheets were marked and drilled from steel master templates, while
stamped sheets were formed from dies which accurately reproduced
a given part exactly over and over again. The only major compound
curves were in the engine cowling, wheel pants and fairings. Nearly
90% of the structure and covering was of one gauge aluminum - 24ST.
In producing the S-C a full-scale plaster model was built
first. Once the shape was finalized, lines were transferred from
the plaster mock-up directly to metal by means of progressive steps.
Shells were built around the fuselage model at bulkhead points and
a compound curve area. Plaster casts were then made and, from these
female castings, master male plaster casts were made.
plaster patterns were used to make sand molds into which was poured
molten zinc metal, thus forming one half of the die. The "punch"
or female half of the die was made by pouring lead directly over
the zinc die. The complete S-C was built up of a little more than
200 individual sets of dies from which all the essential parts of
the plane's structure was formed.
The wing structure was
greatly simplified and its construction of great interest. Again,
the precision of the drop-hammer die-stamping process was utilized.
The wing featured the monospar principle and each panel was attached
to the fuselage by three taper bolts. The spar did not run as one
unit throughout the span. This metal "monocoque spar," as it was
termed, was a Ryan patented development.
In reality, the
spar embodied approximately the full forward-third portion of the
wing. This nose portion was assembled as a single unit with major
stresses carried by the outer skin. It was further stiffened by
the nose ribs and single vertical webs located about one-third of
the chord. Thus, the entire forward portion of the wing formed a
light but strong tapered box spar.
The master spar swept
back from root to tip about 1-1.2 degrees due partially to the 3-degree
washout in the wing, to gain added structural strength as the wing
thinned near the tip, and to retain the correct airfoil shape. This
method of construction is known today as the "D" tube spar and is
used on the popular Mooney.
The wings were formed and assembled
in one continuous operation in a master jig. The trailing portion
was cantilever ribbed. From root to aileron, ribs were built up
from drop-hammer formed cap strips and simple diagonal members.
The outer ribs were stamped in one piece. Final assembly was completed
on the master wing panel jig to assure alignment. The entire S-C
was completely assembled and aligned on but three main jigs.
These processes may seem commonplace today and in many cases
old fashioned. However, in 1936/37 such utilization of metal in
a low-cost, private light plane was a great advance in aircraft
design and construction. For its simple construction the S-C was
beautifully streamlined and efficient. It quickly gained a reputation
as just about the classiest private plane of its day.
Ryan was a remarkable plane, highly maneuverable, responsive to
the controls under all conditions, yet stable enough to be flown
hands off. Careful choice and use of the right airfoil provided
a stable center of pressure which made the natural center of gravity
coincide with the center of pressure throughout the wing. Tests
showed the wing as near perfectly balanced and free from flutter
under all conditions as possible. Stalls were mild, the nose dropping
only slightly below the horizon and aileron control was positive
throughout. Forced loops and spins were possible with the S-C's
but they were placarded against any violent maneuver. They were
not intended as aerobatic machines.
Development of the S-C
was based on the popular acceptance of the model ST low-wing open-cockpit
training plane and interests expressed by dealers and owners for
a companion cabin model. Engineering was placed under the direction
of Millard Boyd and Will von der Meer who previously designed the
ST. The mock-up was built during the spring of 1937 and the flying
prototype completed by mid-summer
Once the shape was
finalized, lines were transferred from the plaster mock-up directly
to metal by means of progressive steps. Shells were built around
the fuselage model at bulkhead points and at compound curve areas.
Plaster casts were then made and, John Fornasero did the initial
flight test work. He was also chief test pilot for Ryan on the ST
The S-C was originally designed to employ the complete
line of Menasco inline air-cooled engines, ranging from the 95-hp
B-4, 125-hp C-4 and the 150-hp C-4S as optional customer choice.
The prototype had the C-4S installed and proved most adaptable from
the standpoint of operational costs versus performance compromise.
Trials continued throughout the summer with the little aircraft
turning in an ideal and enviable performance. The recorded facts
and figures along with its sleek appearance made headlines in all
the leading aviation journals. By late summer the S-C had received
its ATC (No. 651) and the NX 17372 license was changed to NC.
As fall approached, the S-C was put into service at the
Ryan School of Aeronautics in San Diego. Here it served as a primary
trainer, being used for indoctrination into the "first feel of flight."
Several months later a re-evaluation of the S-C was undertaken.
A review of upkeep costs, flight hours, maintenance problems, and
what bearing these would have on the owner of such a plane, was
made. The original S-C was brought back to the factory, the Menasco
engine removed and a seven-cylinder Warner 145-hp radial installed.
This change was dictated purely by engine studies and considerations
With the Warner engine, fuel consumption was
only slightly less than with the Menasco but it proved more reliable,
rugged, easier to maintain and cost less per unit to install. With
the radial engine as power, the entire series of tests had to be
carried out again and the only change found necessary was an added
wing-to-fuselage fairing. This was done in order to retain spin
characteristics for the airplane to be CAA certified. John Fornasero
once again did the early flight work, but most of the later wringing
out was done by Paul Wilcox, who succeeded Fornasero.
prototype now sported the S-CW designation and in October 1937 became
NC 17372 all over again under ATC 658. Production tooling got underway
immediately and material was procured for an initial lot of 25 aircraft
with deliveries to start in the spring of 1938.
was just underway when Claude Ryan announced a new contract for
aircraft parts, putting the company in the position of having over
$300,000 backlog of work. Within a few months of this, Ryan received
overwhelming orders for the STM, military version of the ST trainer.
These orders came in from the U. S. as .well as many foreign governments.
Only 12 S-CWs were built before production had to be stopped in
order to keep up with the more pressing military schedules. It was
hoped the S-C could be brought back but, when war broke out, any
possibilities of resuming commercial production was forgotten for
Initial retail price for the standard S-C
was $6,885 but with extra equipment, which most customers chose
to have installed, the cost was around $7,500. No Menasco or inline
powered S-Cs were delivered to customers. Only the NX prototype
employed this engine for only a few months.
The Ryan S-C
had a top speed of about 140 mph at 5,000 ft. and a cruising speed
of 125 mph. Landing speed was 45 mph. The metal perforated landing
flap, situated between the landing gears, attached at the main spar
line and manually controlled by a lever in the cockpit, was effective
in giving good glide control during approach but had little effect
upon the plane's speed. It in no way changed the stability nor was
there any correction necessary when it was extended. It also provided
a slight assist in short takeoff runs. The sliding cockpit canopy
could be adjusted in flight through intermediate positions between
closed to fully open. No buffeting occurred and there was no change
in trim necessary.
Because of their similarity in planview,
with long tapered wings, fixed spatted undercarriage and general
silhouette, several Ryan S-Cs were used in war movies to represent
early Japanese Nakajima fighters. Many S-Cs played their own war-time
role in the hands of the C.A.P. and one has been unofficially credited
with spotting and sinking or disabling of a German U-Boat off the
Atlantic coast in 1942. Of the 12 S-C's built, one was sold to Brazil
and one was flown to a customer in Mexico City. The other ten were
initially purchased by customers in the U. S.
analysis was made after the war as to the economics of resuming
production of the S-C model. Two versions were to be offered, the
standard S-C145W and an improved S-C165W model with the Warner 165-hp
Super Scarab engine. However, when the opportunity arose to purchase
the rights for the North American Navion, the S-C was abandoned.
The S-C had a comparatively short production life but its appearance
in the late 1930's will long be remembered as just about one of
the classiest private planes to ever flex its wings in flight.
(The author wishes to express his sincere appreciation to
Mr. William Wagner, Vice President, Public Relations, Ryan Aeronautical
Company for his valuable time and assistance with this article.)
<click image for larger version>
image for larger version>
The AMA Plans Service offers a full-size
version of many of the plans show here at a very reasonable cost. They will scale the plans any size for you. It is always
best to buy printed plans because my scanner versions often have distortions that can cause parts to fit poorly. Purchasing
plans also help to support the operation of the Academy of Model
Aeronautics - the #1 advocate for model aviation throughout the world. If the AMA no longer has this plan on file, I
will be glad to send you my higher resolution version.