Dec 08 2010

Rotorcraft Pioneers - Part X: Igor Sikorsky Posted 13 years 142 days ago ago by Admin

By Contributing Editor, Brad McNally - One name more than any other is synonymous with helicopter development, Igor Sikorsky.  Often regarded as the father of the helicopter, Sikorsky was actually an incredibly talented aeronautical engineer who twice established himself as one of the world’s greatest designers of fixed wing aircraft before he built a successful helicopter.  After designing, building and flying the first successful North American helicopter, Igor Sikorsky led the company which still bears his name through over forty years of helicopter innovation.

Igor Ivanovich Sikorsky was born on May 25, 1889 in the Russian city of Kiev, the modern day Ukrainian capital.  Sikorsky was the youngest of Dr. Ivan and Zinaida Sikorsky’s five children.  Dr. Ivan Sikorsky was a psychiatrist and professor at the University of Kiev for over twenty-five years.   Zinaida Sikorsky was a medical school graduate who raised her five children instead of working outside the home.  It was Igor Sikorsky’s mother who first introduced him to aviation and the helicopter when she told him about Leonardo da Vinci’s plans for a vertical flying machine (Dealer, 1969).  At an early age Igor Sikorsky showed great interest in mechanics and science.  Encouraged by his parents, Sikorsky used a back room in their house as a workshop where he built his own toys, experimented with electric motors and even made batteries out of glass jars.  In 1901, at the age of 12, Igor Sikorsky built a rubber band powered helicopter capable of rising several feet before the rubber bands unwound and it settled back to the ground (Sikorsky, 2007).  By 1903, Sikorsky was a fourteen year old budding engineer.  However, he put his engineering endeavors on hold to enter the Imperial Naval Academy in St. Petersburg, Russia.  After three years, Sikorsky left the Naval Academy and returned to Kiev where he enrolled in the Kiev Polytechnic Institute and resumed his engineering pursuits.  While on vacation with his father in the Bavarian Alps in 1908, nineteen year old Igor Sikorsky became fascinated with German newspaper stories about the Wright brothers and saw his first pictures of the airplanes the Wrights had designed.  It was this experience that set Igor Sikorsky on a lifelong pursuit of aeronautical engineering.

After returning to Kiev, Igor Sikorsky began to collect any information he could find about aeronautics and started designing his first aircraft, which was to be a helicopter.  In 1909, Sikorsky’s sister Olga financed a trip for him to travel to Paris, which was at the time the center of the aeronautical world.  While in Paris, Sikorsky was able to see up close many different aircraft, some which flew and others which did not.  Igor returned home with a greater knowledge of aircraft designs and a twenty-five horsepower Anzani engine (Sikorsky, 2007).  This new engine was used as the power plant for Sikorsky’s first helicopter, the H-1.  Igor first tested the H-1 in 1909 and quickly encountered many problems including vibrations and a lack of power.  Sikorsky later determined the H-1 was only capable of lifting about 350 pounds which was 100 pounds less than its own weight (Dealer, 1969).  An improved version, the H-2, was first tested in 1910.  The H-2 had a similar coaxial configuration as the H-1 but through improved performance it was able to lift its own weight.  Igor Sikorsky realized his helicopter designs were not capable of lifting a pilot and put helicopter development on hold in favor of designing fixed wing aircraft.

While still developing the H-2, Igor Sikorsky had started working on his first fixed wing design.  The S-1 was a fifteen horsepower biplane, with a wooden structure and bicycle wheels.  Although the S-1 never got into the air it was an important stepping stone in Sikorsky’s personal development as an aeronautical engineer and pilot.  The S-1 taught Igor a lot about how to control an airplane and led to the improved S-2.  The S-2 featured a larger, more powerful twenty-five horsepower engine which was mounted at the front of the aircraft in a tractor configuration instead of at the rear in the pusher configuration of the S-1.  The S-2, along with the S-3 and S-4 never flew more than short hops, but each aided in Sikorsky’s design and piloting abilities.  During this time Igor Sikorsky made the decision to leave school to focus on his aeronautical endeavors.  It wasn’t until 1911 and the development of the S-5, which had a fifty horsepower Argus engine, that Igor was able to make his first practical flight.  This fight occurred on May 11, 1911 when Sikorsky climbed the S-5 to an altitude of 300 feet, circled the field and then landed back where he had taken off.  Several months later the S-5 with Sikorsky at the controls, was flying for over one hour at altitudes up to 1,500 feet (Sikorsky, 2007).  Also in 1911, Igor Sikorsky received his Federation Aeronautique Internationale pilot’s license and flew the S-5 to four Russian records for altitude, speed, range and endurance.

In February of 1912, the S-6A won the Great Gold Medal as the best aircraft at the Moscow Aeronautical Exhibition.  This award generated significant interest in Sikorsky’s piloting abilities and his aircraft designs.  Igor Sikorsky accepted an offer to become the chief engineer and test pilot for the newly formed aviation division of the Russian-Baltic Railcar Factory, one of Russia’s largest industrial companies.  In 1913, Igor Sikorsky designed, built and flew one of his greatest aeronautical achievements.  The aircraft was known as The Grand and it would become the world’s first successful four engine aircraft (Dealer, 1969).  The Grand was a revolutionary design which had dual controls, an enclosed cockpit it’s four man crew (two pilots, one mechanic and one navigator) and a cabin with four seats, a sofa, washroom, table and a coat closet.  Less than ten years after the Wright brothers first flight, the Grand set a record by flying with eight passengers for over one hour and fifty minutes.  The Grand generated so much interest, Czar Nicholas II requested it be flown to a military airport so he could view the aircraft and personally meet with Igor Sikorsky (Sikorsky, 2007).  The Grand would ultimately become the precursor to the larger airplanes that would revolutionize air travel and make airline transportation what it is today.

Just as Igor Sikorsky was beginning to make his mark as an aircraft designer, the Bolshevik Revolution was sweeping across Russia.  The decision to leave Russia weighed heavily on Sikorsky.  Ultimately, he realized the chaos and disorder caused by the Bolshevik Revolution would not allow him to continue his aeronautical endeavors.  In 1918, Igor Sikorsky left behind his loved ones and a fortune worth about a half million dollars when he boarded a ship in Murmansk headed for England.  Igor made his way to Paris where he started work on a new French military bomber.  However, World War I ended before the bomber was completed.  The European post-war aviation industry subsequently went into decline and the French bomber project was canceled (Dealer, 1969).  With little hope of having any aviation success in Europe and unable to return to Russia, Sikorsky decided he would head to America to begin a new life and resume his aviation career.  In March of 1919, Igor Sikorsky arrived in New York with no friends, no job and only $600.  Sikorsky tried to restart his aviation career but found it difficult to compete with the price of surplus military aircraft being sold by the government after the war.  Igor Sikorsky struggled to get by for several years and found work teaching math and physics at a Russian refugee school (Sikorsky, 2007).
 
In 1922, urged on by a former Russian Navy pilot who offered the use of his farm and home on Long Island, Igor Sikorsky resumed his aviation endeavors.  Four years after arriving in the United States, Sikorsky founded the Sikorsky Aero Engineering Corporation on March 5, 1923.  His first American design was the S-29A, a biplane powered by two 400 horsepower engines with room for fourteen passengers.  It was the largest airplane ever constructed in America at the time.  Although the S-29A design was sound and some interest was generated, money was sparse for Sikorsky’s struggling company.  Fortunately, this changed in 1927 when Charles Lindbergh made his historic flight across the Atlantic.  Overnight there was tremendous interest in aviation.  Sikorsky ventured into seaplanes and later developed a series of revolutionary amphibious designs starting with the S-38 and ending with the S-44.  Especially innovative was the S-42 which first flew in 1934.  The S-42 set world records for range, payload and speed which were previously thought unattainable.  These amphibians helped bring about the air transportation system we know today by linking the United States, the Caribbean and South America and later making transatlantic and transpacific routes possible.  In 1929, the Sikorsky Aviation Corporation became a subsidiary of the United Aircraft and Transport Company (later known as United Technologies).  During reorganization within United Aircraft brought about by World War II, Sikorsky Aviation merged with Chance Vought resulting in Vought-Sikorsky.  Subsequent aircraft designs were designated with a VS prefix to represent the merged companies.

Igor Sikorsky never gave up on building a successful helicopter.  Even as his flying boats were meeting with great success in the late 1920s and early 1930s, Sikorsky continued to refine his helicopter designs.  By the late 1930s the sea plane market was declining rapidly due in large part to the construction of land based airfields and the rapid expansion of aviation brought about by World War II.  In 1938, United Aircraft decided to shut down its Sikorsky Aircraft division.  Seeing this as possibly his last opportunity to achieve his dream of rotary winged flight, Igor Sikorsky was able to persuade United Aircraft to allow him to retain a small group of engineers to develop a helicopter (Spenser, 1998).  This was a tough sell to the United Aircraft leadership as helicopters were considered both impossible and impractical in the 1930s.  However, Sikorsky’s reputation as a great designer coupled with his honesty and humility earned him the chance he had been hoping for.  Igor Sikorsky quickly went to work designing and building what would become the first North American helicopter, the VS-300.  Powered by a seventy-five horsepower Lycoming engine and utilizing a single main rotor and tail rotor configuration, the VS-300 first lifted off of the ground on September 14, 1939 (Sikorsky, 2007).  In May of 1940, Igor Sikorsky made the first public demonstration flights in the VS-300 and was subsequently issued the first helicopter license by the National Aeronautic Association of the United States.  The VS-300 went through many design changes as it was used to solve such defining helicopter problems as control, stability, gyroscopic precession and vibrations.  Along with using the VS-300 to test out his ideas, Sikorsky taught himself and several others to fly helicopters.  Sikorsky flew the VS-300 to a world endurance record of one hour, twenty minutes and thirty-nine seconds in May of 1941.  On October 7, 1943, Igor Sikorsky personally donated the VS-300 to Henry Ford for inclusion in the Edison Institute Museum in Michigan.  At the time of the donation this historic aircraft had just over 102 hours of flight time (Spenser, 1998).

Based on the success of the prototype VS-300, the U.S. Army formally contracted with Sikorsky Aircraft to build a larger helicopter in 1941.  This helicopter would be known as the VS-316 or more commonly the R-4.  The R-4 made the first extended cross country helicopter flight in North America when it flew from the Sikorsky factory in Connecticut to Wright Field in Ohio and was officially delivered to the Army on May 18, 1942.  The R-4 would become the world’s first production helicopter with an eventual 131 being built for the American and British militaries (Sikorsky, 2007).  Helicopter production led to Vought-Sikorsky being disbanded in 1943 to allow Sikorsky Aircraft to move to a larger production facility in Bridgeport, CT.  Igor Sikorsky had long believed if a successful helicopter could be built, it could be a tremendously useful asset for saving human life.  The R-4 was the first of many helicopters to prove that Sikorsky’s prediction was correct.  In January of 1944 a Coast Guard officer named Frank Erickson flew through a fierce winter storm in a Sikorsky HNS-1 (R-4) with much needed blood plasma for sailors injured in an explosion.  Later that year, Army Lieutenant Carter Harman conducted the first ever combat helicopter rescue when he flew a Sikorsky R-4 behind enemy lines, into Japanese held Burma, to rescue four downed Allied soldiers (Sikorsky, 2007).  Prior to the end of World War II, Igor Sikorsky and his team had developed two new helicopters.  The R-5 was an all new design which boasted a 450 horsepower Pratt and Whitney engine with a payload of 1,500 pounds.  The R-6 was an improved version of the R-4.  Before the war ended, 225 R-6s were built.  After World War II military interest in the helicopter decreased, many helicopter programs were cancelled and a substantial commercial market failed to materialize.  All of this caused sales to drop considerably and further delayed helicopter development.
 
Within a few years there would be another major war and helicopters would play a much more important role in battlefield operations.  Although the helicopter saw only limited use for lifesaving purposes during and after World War II, it proved Igor Sikorsky’s predictions about its life saving ability on a much larger scale during the Korean War.  Spurred on by the success of the helicopter in Korea and increased interest in the commercial market Sikorsky Aircraft pushed ahead with larger and more capable helicopter designs.  An improved version of the R-5, the S-51, became the second helicopter certified for civil use.  The S-51 was used for the first helicopter airline in 1946 and its operations during the Korean War helped establish the helicopter medevac role.  Over 330 S-51s were produced by Sikorsky Aircraft or under license in Britain.  The S-51 served in all branches of the U.S. military and a dozen foreign militaries.  Throughout the 1950s, many new helicopter designs were produced, each one more capable than the last.  Included in this development were the S-55 and S-58.  Both of these helicopters were revolutionary designs which helped establish Sikorsky Aircraft as one of the leading manufacturers of large helicopters.  The S-55 was designed and built in less than six months for an Air Rescue Service requirement (Sikorsky, 2007).  Powered by a 600 horsepower engine, the S-55 saw use in both civil and military applications.  Over 1750 S-55s were produced by Sikorsky Aircraft or under license in England, France and Japan.  The S-58 was an improved version of the S-55 which first flew in 1954 and boosted a 1,525 horsepower Wright engine.  Known in the U.S. military as the venerable H-34, the S-58 had a production run lasting for twenty-five years with over 2,300 aircraft being built.  Later model S-58s featured two General Electric T-58 turbines and many early S-58s underwent a turbine conversion resulting in a power increase to 1,800 horsepower and the new designation S-58T.

After steadily guiding the Sikorsky Aircraft Company and firmly establishing it as a leader in the helicopter industry, Igor Sikorsky retired as engineering manager for Sikorsky Aircraft in 1957.  Even after retiring, Sikorsky was never far from the cutting edge of helicopter development and remained active in the company as a consultant.  Igor Sikorsky was involved in the development of the S-61, a revolutionary twin turbine powered amphibious helicopter which first flew in 1959.  S-61s, or the military version the H-3, became known as such versatile and dependable helicopters they were built under license in several foreign countries.  Over fifty years after this design first flew, S-61s are still in service today, including being used by Marine Helicopter Squadron One (HMX-1) as the President’s helicopter, Marine One.  Igor Sikorsky’s final project was the S-64 or Flying Crane.  Starting as the S-60 in 1958, improvements resulted in the S-64 which first flew in 1962.  The military version was known as the CH-54 Tarhe and it saw significant use in Vietnam.  Although the Flying Crane was not as commercially successful as some other models, it did push the concept of a heavy lift helicopter forward and S-64s are still flying today in a variety of heli-logging, fire fighting and heavy lift applications.
 
Igor Sikorsky passed away in his sleep on October 26, 1972 at the age of 83.  His office is today the same as it was when he left work on the day he died.  It is viewable inside the Sikorsky Aircraft factory in Stratford, CT behind a glass partition.  It has been kept intact as a memorial to the man who helped usher in a new era in aviation and whose vision and ideals made Sikorsky Aircraft one of the leaders in the helicopter industry.  During his aviation careers, Igor Sikorsky accumulated an impressive list of accolades.  According to the Sikorsky Historical Archives, he received over eighty honors, awards and certificates between 1933 and 1971.  Included in this list are nine honorary doctorates, six fellowships, the Silver Medal of the Royal Aeronautical Society, the Presidential Certificate of Merit from President Harry Truman, the Wright Trophy, the National Medal of Science from President Lyndon Johnson and the Daniel Guggenheim Medal.  The American Helicopter Society twice recognized Igor Sikorsky as a Honorary Fellow (1944 and 1960), awarded him the Grover F. Bell Award for fostering and encouraging research and experimentation in helicopter development and the first ever Dr. Alexander Klemin Award for notable achievement in advancement of rotary wing aeronautics.  Today the American Helicopter Society annually presents the Igor I. Sikorsky International Trophy to the company that develops a helicopter establishing an official record during the preceding year.  To commemorate the vision Igor Sikorsky had of the helicopter being a machine capable of saving human life, the Sikorsky Aircraft Company presents the Winged S Rescue Award to aircrews that save a life using a Sikorsky helicopter.

Many people wrongfully acknowledge Igor Sikorsky as the inventor of the helicopter.  This was a misunderstanding Sikorsky himself tried to correct by pointing out he neither invented the helicopter nor the single main rotor and tail rotor configuration he made a key feature of Sikorsky designs (Spenser, 1998).  In reality no one person invented the helicopter.  There were many hard earned developments which led to the helicopter becoming a reality in Europe and the United States in the late 1930s and early 1940s.  However, Igor Sikorsky certainly played a pivotal role in all of this by developing the first successful North American helicopter, cultivating the single main rotor configuration that has become the most common configuration in subsequent helicopter designs and making significant advances in helicopter technology.  The company he founded continues to carry on his trademarks of innovation and performance with current models such as the S-76, S-92, S-70 Hawk series and the X-2.  His legacy as a great aeronautical engineer and leader in helicopter development make him a true Rotorcraft Pioneer.

References

Dealer, F. J. (1969). Igor Sikorsky His Three Careers in Aviation. New York: Dodd, Mead and Company.
Sikorsky, S. I. (2007). The Sikorsky Legacy. Charleston, SC: Arcadia Publishing.
Spenser, J. P. (1998). Whirlybirds: A History of the U.S. Helicopter Pioneers. Seattle, WA: University of Washington Press.