Ryan ST
Encyclopedia
The Ryan STs were a series of two seat, low-wing monoplane
Monoplane
A monoplane is a fixed-wing aircraft with one main set of wing surfaces, in contrast to a biplane or triplane. Since the late 1930s it has been the most common form for a fixed wing aircraft.-Types of monoplane:...
aircraft built by the Ryan Aeronautical Company
Ryan Aeronautical Company
The Ryan Aeronautical Company was founded by T. Claude Ryan in San Diego, California in 1934. Part of Teledyne after 1969, Northrop Grumman purchased Teledyne Ryan in 1999...
. They were used as sport aircraft
Aircraft
An aircraft is a vehicle that is able to fly by gaining support from the air, or, in general, the atmosphere of a planet. An aircraft counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines.Although...
, as well as trainers
Trainer (aircraft)
A trainer is a class of aircraft designed specifically to facilitate in-flight training of pilots and aircrews. The use of a dedicated trainer aircraft with additional safety features—such as tandem flight controls, forgiving flight characteristics and a simplified cockpit arrangement—allows...
by flying schools and the military of several countries.
Design and development
T. Claude RyanT. Claude Ryan
Tubal Claude Ryan was an Irish-American aviator born in Parsons, Kansas. Ryan was best known for founding some airlines and four airplane factories.-Business career:...
was the founder of the Ryan Aeronautical Company, the second incarnation of a company with this name, and the fourth company with which he had been involved to bear his name (the first, Ryan Airlines, was the manufacturer of the Ryan NYP, more famously known as the Spirit of St. Louis
Spirit of St. Louis
The Spirit of St. Louis is the custom-built, single engine, single-seat monoplane that was flown solo by Charles Lindbergh on May 20–21, 1927, on the first non-stop flight from New York to Paris for which Lindbergh won the $25,000 Orteig Prize.Lindbergh took off in the Spirit from Roosevelt...
). He began the development of the ST (for "Sport Trainer", and also known as S-T), the first design of the company, in 1933.
The ST featured two open cockpit
Cockpit
A cockpit or flight deck is the area, usually near the front of an aircraft, from which a pilot controls the aircraft. Most modern cockpits are enclosed, except on some small aircraft, and cockpits on large airliners are also physically separated from the cabin...
s in tandem
Tandem
Tandem is an arrangement where a team of machines, animals or people are lined up one behind another, all facing in the same direction....
in a metal semi-monocoque
Monocoque
Monocoque is a construction technique that supports structural load by using an object's external skin, as opposed to using an internal frame or truss that is then covered with a non-load-bearing skin or coachwork...
fuselage
Fuselage
The fuselage is an aircraft's main body section that holds crew and passengers or cargo. In single-engine aircraft it will usually contain an engine, although in some amphibious aircraft the single engine is mounted on a pylon attached to the fuselage which in turn is used as a floating hull...
of two main frames - one steel, the other half of steel and half of aluminium alloy (alclad
Alclad
Alclad is a trademark of Alcoa used as a generic term to describe corrosion resistant aluminium sheet formed from high-purity aluminium surface layers metallurgically bonded to high strength aluminium alloy core material. These sheets are commonly used by the aircraft industry...
) - to take the loads from the wing spars
Spar (aviation)
In a fixed-wing aircraft, the spar is often the main structural member of the wing, running spanwise at right angles to the fuselage. The spar carries flight loads and the weight of the wings whilst on the ground...
and six more alclad frames; and alclad skin. It had wings in three sections of hybrid construction; the centre section integral with the fuselage had tubular steel spars, the front spar a simple tube with an external brace to the upper fuselage, and the rear spar in the form of a parallel chord truss
Truss
In architecture and structural engineering, a truss is a structure comprising one or more triangular units constructed with straight members whose ends are connected at joints referred to as nodes. External forces and reactions to those forces are considered to act only at the nodes and result in...
. The two outer wing panels had wooden spars and alclad ribs, with diagonal rods bracing the wings internally. Alclad sheet was used to form the leading edges, and fabric covered the whole structure. When attached the outer wings were braced with flying wires
Flying wires
The flying wires of an aircraft work in conjunction with other wing components such as spars and interplane struts to transmit flight loads. Most commonly used on biplane aircraft they are also used on monoplanes and triplanes.-Purpose:...
to the fixed conventional landing gear
Conventional landing gear
thumb|The [[Piper PA-18|Piper Super Cub]] is a popular taildragger aircraft.thumb|right|A [[Cessna 150]] converted to taildragger configuration by installation of an after-market modification kit....
and landing wires to the upper fuselage.
Five STs were built before the follow-on ST-A (also S-T-A) (A for Aerobatic
Aerobatics
Aerobatics is the practice of flying maneuvers involving aircraft attitudes that are not used in normal flight. Aerobatics are performed in airplanes and gliders for training, recreation, entertainment and sport...
) was developed with a more powerful engine. A single ST-B was produced, this being an ST-A with only one seat and an extra fuel tank where the front cockpit normally was; this aircraft was subsequently converted back to ST-A standard. The ST-A was further developed as the ST-A Special, with an engine of increased power.
In 1937 the ST-A Special was developed into a military version, the STM (also ST-M) series. Changes included wider cockpits to enable military pilots to enter and exit while wearing parachute
Parachute
A parachute is a device used to slow the motion of an object through an atmosphere by creating drag, or in the case of ram-air parachutes, aerodynamic lift. Parachutes are usually made out of light, strong cloth, originally silk, now most commonly nylon...
s, and provision for a machine gun on some examples. Variants in the series included the STM-2P single-seat version armed with a machine gun
Machine gun
A machine gun is a fully automatic mounted or portable firearm, usually designed to fire rounds in quick succession from an ammunition belt or large-capacity magazine, typically at a rate of several hundred rounds per minute....
delivered to Nationalist China
Kuomintang
The Kuomintang of China , sometimes romanized as Guomindang via the Pinyin transcription system or GMD for short, and translated as the Chinese Nationalist Party is a founding and ruling political party of the Republic of China . Its guiding ideology is the Three Principles of the People, espoused...
; and the STM-S2, which could be fitted with landing gear or with EDO Model 1965
EDO Corporation
EDO Corporation was an American company, which was acquired by ITT Corporation in 2007. EDO designed and manufactured products for defense, intelligence, and commercial markets, and provided related engineering and professional services. It employed 4,000 people worldwide and had revenues of $715...
floats
Floatplane
A floatplane is a type of seaplane, with slender pontoons mounted under the fuselage; only the floats of a floatplane normally come into contact with water, with the fuselage remaining above water...
.
After the ST-M came the ST-3, a substantial redesign in 1941 partly brought about by the unreliability of the Menasco engines fitted to STs to that point. The United States Army Air Corps
United States Army Air Corps
The United States Army Air Corps was a forerunner of the United States Air Force. Renamed from the Air Service on 2 July 1926, it was part of the United States Army and the predecessor of the United States Army Air Forces , established in 1941...
(USAAC) had purchased several dozen ST-M variants under various designations and had Ryan Aeronautical re-engine most with Kinner R-440
Kinner B-5
|-See also:-References:* http://www.oldengine.org/members/diesel/Duxford/usaero4.htm-External links:...
radial engines. The USAAC found the modification to be beneficial and asked Ryan Aeronautical to design a variant with this engine as standard, and with airframe modifications considered desirable from in-service experience. The ST-3 that resulted featured a longer and more circular wider fuselage, this being suggested by the circular radial engine. Other changes included a revised rudder, balanced ailerons and elevators, and strengthened main landing gear with the legs spaced further apart. The streamlining spats covering the mainwheels, found on ST series aircraft to that point, were deleted as well. The ST-3 served as the basis for military versions ordered by the USAAC and the United States Navy
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
(USN).
The ST-3 gave rise to another model developed in 1941 and early 1942, this was the ST-3KR (for Kinner Radial). The ST-3KR had a more powerful Kinner R-5
Kinner R-5
|-See also:-References:* http://www.oldengine.org/members/diesel/Duxford/usaero4.htm...
engine fitted and became the definitive model; more than 1,000 military versions were built during World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
as PT-22 Recruits. The final variant was the ST-4, which was a version of the ST-3 with a wooden fuselage, developed in case a shortage of "strategic materials" (i.e. of metal) developed. Such a shortage did not eventuate and the ST-4 was not put into mass-production.
The first Ryan ST flew for the first time on 8 June 1934 and production began the following year, when nine aircraft were delivered. Except for 1937 (when 46 aircraft were built), production rates remained low for several years, at about one aircraft every two weeks. This changed in 1940 when deliveries to military forces began in earnest; production that year was just under three aircraft per week. Total production of civil and military aircraft prior to the entry of the United States into World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
amounted to 315. Another 1,253 military versions were produced in 1942 and 1943, for a total of 1,568 aircraft of all models.
Operational history
Most civil aircraft in the ST series were delivered in the United States, although a few were exported to South AfricaSouth Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
, Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
and various countries in Latin America
Latin America
Latin America is a region of the Americas where Romance languages – particularly Spanish and Portuguese, and variably French – are primarily spoken. Latin America has an area of approximately 21,069,500 km² , almost 3.9% of the Earth's surface or 14.1% of its land surface area...
. An example of the ST-A was procured by the USAAC in 1939 for evaluation as the XPT-16. This was followed by 15 YPT-16s, the first time the USAAC had ordered a monoplane trainer. These were the first of more than 1,000 Ryan STs to serve the USAAC, its successor the United States Army Air Forces
United States Army Air Forces
The United States Army Air Forces was the military aviation arm of the United States of America during and immediately after World War II, and the direct predecessor of the United States Air Force....
(USAAF) and the USN.
A large number of STMs were exported in the 1930s and early 1940s (prior to the entry of the United States into World War Two) to various Air force
Air force
An air force, also known in some countries as an air army, is in the broadest sense, the national military organization that primarily conducts aerial warfare. More specifically, it is the branch of a nation's armed services that is responsible for aerial warfare as distinct from an army, navy or...
s, with the biggest customer being the military of the Netherlands East Indies
Dutch East Indies
The Dutch East Indies was a Dutch colony that became modern Indonesia following World War II. It was formed from the nationalised colonies of the Dutch East India Company, which came under the administration of the Netherlands government in 1800....
(NEI, now Indonesia
Indonesia
Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...
). The NEI Army and Navy took delivery of 84 STM-2s and 24 STM-S2s in 1940 and early 1941. Another 50 STM-2Es and STM-2Ps were exported to Nationalist China, while others were exported to Bolivia
Bolivia
Bolivia officially known as Plurinational State of Bolivia , is a landlocked country in central South America. It is the poorest country in South America...
, Ecuador
Ecuador
Ecuador , officially the Republic of Ecuador is a representative democratic republic in South America, bordered by Colombia on the north, Peru on the east and south, and by the Pacific Ocean to the west. It is one of only two countries in South America, along with Chile, that do not have a border...
, Guatemala
Guatemala
Guatemala is a country in Central America bordered by Mexico to the north and west, the Pacific Ocean to the southwest, Belize to the northeast, the Caribbean to the east, and Honduras and El Salvador to the southeast...
, Honduras
Honduras
Honduras is a republic in Central America. It was previously known as Spanish Honduras to differentiate it from British Honduras, which became the modern-day state of Belize...
, Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
and Nicaragua
Nicaragua
Nicaragua is the largest country in the Central American American isthmus, bordered by Honduras to the north and Costa Rica to the south. The country is situated between 11 and 14 degrees north of the Equator in the Northern Hemisphere, which places it entirely within the tropics. The Pacific Ocean...
.
After the Japanese invasion of the NEI many Ryans in that country were pressed into combat, especially in reconnaissance
Reconnaissance
Reconnaissance is the military term for exploring beyond the area occupied by friendly forces to gain information about enemy forces or features of the environment....
roles, and large numbers were shot down or destroyed on the ground. Surviving STM-2s and STM-S2s that were not captured by the Japanese were shipped to Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
, where 34 entered service in the Royal Australian Air Force
Royal Australian Air Force
The Royal Australian Air Force is the air force branch of the Australian Defence Force. The RAAF was formed in March 1921. It continues the traditions of the Australian Flying Corps , which was formed on 22 October 1912. The RAAF has taken part in many of the 20th century's major conflicts...
as trainers. Many of those that survived until the end of World War Two were then placed on the civil register in Australia and elsewhere, and some are still flying almost 70 years after they were built.
Manufacturer designations
ST-A: Improved ST designed for aerobatics, fitted with a Menasco C4
Menasco C4
The Menasco Pirate series were popular 4-cylinder, air-cooled, in-line, inverted, aero-engines, for use in light general and sport aircraft during the 1930s and 1940s...
engine of 125 hp; 73 built.
ST-A Special: Improved ST-A, fitted with a Menasco C4S
Menasco C4
The Menasco Pirate series were popular 4-cylinder, air-cooled, in-line, inverted, aero-engines, for use in light general and sport aircraft during the 1930s and 1940s...
engine of 150 hp; 10 built.
ST-B: Single-seat variant of ST-A with extra fuel tank in place of front cockpit; one built, later converted to ST-A.
STM: Military version of ST-A Special with wider cockpits, some with provision for a machine gun; 22 built.
STM-2: Variant of STM for Netherlands East Indies Army and Navy; 95 built.
STM-2E: Variant of STM delivered to China, fitted with a Menasco C4S2
Menasco C4
The Menasco Pirate series were popular 4-cylinder, air-cooled, in-line, inverted, aero-engines, for use in light general and sport aircraft during the 1930s and 1940s...
engine of 165 hp; 48 built.
STM-2P: Single-seat variant of the STM-2E with provision for a machine gun, also delivered to China; 2 built.
STM-S2: Variant of STM-2 with interchangeable wheel landing gear or floats for Netherlands East Indies Navy; 13 built.
ST-W: Experimental conversions, with a Warner Scarab
Warner Scarab
|-See also:-References:*-External links:*...
radial engine; one converted from USAAC YPT-16 with Scarab of 125 hp; one converted from USAAC PT-20A with Super Scarab of 160 hp.
ST-3: Variant with new fuselage shape and a Kinner B-5
Kinner B-5
|-See also:-References:* http://www.oldengine.org/members/diesel/Duxford/usaero4.htm-External links:...
radial engine of 125 hp; one built.
ST-3KR: Variant of ST-3 with a Kinner R-5
Kinner R-5
|-See also:-References:* http://www.oldengine.org/members/diesel/Duxford/usaero4.htm...
radial engine of 160 hp, one built.
ST-4: Variant of ST-3 manufactured with wooden fuselage; one built.
USAAC/USAAF
PT-16- XPT-16: A single ST-A bought by the USAAC for evaluation.
- XPT-16A: XPT-16 re-engined with Kinner R-440Kinner B-5|-See also:-References:* http://www.oldengine.org/members/diesel/Duxford/usaero4.htm-External links:...
radial engine of 125 hp. - YPT-16: A total of 15 aircraft similar to the ST-M ordered for service trials.
- PT-16A: 14 YPT-16s re-engined with Kinner R-440 engine.
PT-20: Production version of PT-16; 30 built.
- PT-20A: Designation of PT-20s that were re-engined with Kinner R-440 engines.
PT-21: Military production version of ST-3; 100 built.
PT-22 Recruit: Military production version of ST-3KR with Kinner R-540-1
Kinner R-5
|-See also:-References:* http://www.oldengine.org/members/diesel/Duxford/usaero4.htm...
engine; 1,048 built, including PT-22As.
- PT-22A: Designation for 25 examples of ST-3KR built for the Royal Netherlands Air ForceRoyal Netherlands Air ForceThe Royal Netherlands Air Force , Dutch Koninklijke Luchtmacht , is the military aviation branch of the Netherlands Armed Forces. Its ancestor, the Luchtvaartafdeling of the Dutch Army was founded on 1 July 1913, with four pilots...
but not delivered, aircraft subsequently taken by the USAAF. - PT-22C: Aircraft re-engined with Kinner R-540-3Kinner R-5|-See also:-References:* http://www.oldengine.org/members/diesel/Duxford/usaero4.htm...
engines, 250 aircraft modified.
YPT-25: Military version of ST-4, ordered for evaluation; five built.
Operators
- Royal Australian Air ForceRoyal Australian Air ForceThe Royal Australian Air Force is the air force branch of the Australian Defence Force. The RAAF was formed in March 1921. It continues the traditions of the Australian Flying Corps , which was formed on 22 October 1912. The RAAF has taken part in many of the 20th century's major conflicts...
Bolivia
Guatemala
Netherlands East Indies
- Royal Netherlands East Indies Army Air ForceRoyal Netherlands East Indies Army Air ForceThe Royal Netherlands East Indies Army Air Force was the air arm of the Royal Netherlands East Indies Army in the Dutch East Indies from 1939 until 1950...
- Royal Netherlands NavyRoyal Netherlands NavyThe Koninklijke Marine is the navy of the Netherlands. In the mid-17th century the Dutch Navy was the most powerful navy in the world and it played an active role in the wars of the Dutch Republic and later those of the Batavian Republic and the Kingdom of the Netherlands...
Nicaragua- United States Army Air CorpsUnited States Army Air CorpsThe United States Army Air Corps was a forerunner of the United States Air Force. Renamed from the Air Service on 2 July 1926, it was part of the United States Army and the predecessor of the United States Army Air Forces , established in 1941...
- United States Army Air Force
- United States NavyUnited States NavyThe United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
Specifications (ST-A)
See also
External links
- The Ryan ST page
- Popular Mechanics, February 1943, "Plywood Trainer Saves Metal for Warplanes" shows ST-4 wooden construction