Tag Archives: World Record for Duration

17 March 1929

Louise Thaden at Oakland Municipal Airport with a Beech Travel Air, 1929. (NASM-SI-83-2145)

17 March 1929: Louise Thaden, flying a Beech Travel Air 3000, NC5426, over Oakland, California, set a new Fédération Aéronautique Internationale (FAI) World Record for Duration, staying aloft for 22 hours, 3 minutes.¹ This flight broke the previous record which had been set five weeks earlier, 10–11 February, by Evelyn (“Bobbie”) Trout—which had broken the record set 2 January 1929 by Elinor Smith.

The Oakland Chapter of the National Aeronautic Association wanted to have all new U.S. records set at Oakland, and Mrs. Thaden’s duration flight was a part of that campaign. Officials from the Oakland NAA group observed her flight in order to certify the record for the international body, the FAI.

Douglas C. Warren’s Travel Air 3000, NC5426, flown by Louise Thaden to set a World Record for Duration, (San Diego Air & Space Museum Archives, Catalog #: 00072288)

The airplane flown by Mrs. Thaden for her duration record was a Travel Air 3000, registration NC5426, serial number 51?. The airplane was modified with an auxiliary fuel tank in the forward cockpit.

The Travel Air 3000 was a single-engine, three-place, single-bay biplane with fixed landing gear. The airplane was 24 feet, 3 inches (7.391 meters) long, with an upper wing span of 34 feet, 8 inches (10.566 meters), and lower span of 28 feet, 8 inches (8.738 meters). The airplane had an overall height of 9 feet, 0 inches (2.743 meters). The 3000 had an empty weight of 1,664 pounds (755 kilograms), and gross weight of 2,590 pounds (1,175 kilograms).

Louise Thaden flying the Travel Air 3000, NC5426, during her duration record attempt, 17 March 1929. The auxiliary fuel tank fills the airplane’s forward cockpit. (San Diego Air & Space Museum)

Travel Air biplanes could be ordered with several different air-cooled or water-cooled engines, such as the Curtiss OX-5, the 120 h.p. Fairchild Caminez 4-cylinder radial, or the Wright Whirlwind. The 3000 was equipped with a liquid-cooled, normally-aspirated Hispano-Suiza 8Ac V-8 (according to FAI records). For the record flight the engine was replaced with a “souped-up” engine.

The Travel Air 3000 had a cruise speed of 105 miles per hour (169 kilometers per hour), and a maximum speed of 119 miles per hour (192 kilometers per hour). Its service ceiling was 17,000 feet (5,182 meters), and the maximum range was 400 miles (644 kilometers).

The Travel Air Manufacturing Company built approximately 50 of the “Hisso-powered” Travel Air 3000 variant.

Louise Thaden waves from the cockpit of the Travel Air 3000, NC5426. The forward cockpit has been modified to accept a large auxiliary fuel tank. (San Diego Air & Space Museum)

The Oakland Tribune reported:

WOMAN FLIER BREAKS RECORD

Oakland Aviatrix Sets World Mark for Endurance Flight

     Mrs. Louise McPhetridge Thaden wants to break more aviation records, she declared at Oakland airport today. Already holder of the altitude record for women and having brought her biplane to earth here yesterday with a new women’s endurance flight record, she now is thinking about establishing new altitude and speed marks for women.

     For 22 hours, 3 minutes and 25 seconds, Mrs. Thaden kept her plane in teh air over Oakland airport yesterday, fighting against drowsiness and night cold to beat the former women’s sustained flight record of 17 hours, 5 minutes, 37 seconds, recently established by Miss Bobby Trout of Los Angeles.

      It was at noon yesterday that Mrs. Thaden signalled to planes flying close to her that her gasoline supply was getting low.. Still she kept circling over the airport while thousands waited on the ground below, eager to see her and greet her when she landed.

12 GALLONS OF GAS REMAIN AT FINISH.

     Mrs. Thaden made one last great circle of the flying field and brought her plane to earth at 1:55 p.m. She taxied her plane to a hangar, where officials of the Oakland chapter, National Aeronautic association, newspaper men and friends waited to welcome her. Examination of the plane showed that only 12 gallons of 196 gallons of gasoline were left.

     As friends helped her out of the cockpit where she had sat in a cramped position without sleep, she smiled and said: “Well, I made it. But, gosh, I’m tired.”

     Thousands who had waited at the Oakland airport since early morning cheered Mrs. Thaden, and police were busy keeping them from crushing her in their desire to see the flier and her record plane.

     Mrs. Thaden was greeted first with a hug and a kiss from Mrs. Hattie V. Thaden, her mother-in-law, who had waited through the long night at the airport, confident that her son’s wife would succeed in her record-seeking attempt.

Oakland Tribune, Vol. CX, No. 77, Monday, 18 March 1929, Page 1, Column 5, and Page 2, Column 2

Iris Louise McPhetridge was born 12 November 1905 at Bentonville, Arkansas. She was the first of three daughters of Roy Fry McPhetridge, owner of a foundry, and Edna Hobbs McPhetridge. She was educated at the University of Arkansas at Fayetteville, a member of the Class of 1927. She was president of the Delta Delta Delta (ΔΔΔ) Sorority, Delta Iota (ΔΙ) Chapter, head sports for basketball and president of The Panhellenic.

Iris Louise McPhetridge Thaden (San Diego Air & Space Museum Archives)

Louise McPhetridge had been employed by Walter Beech as a sales representative for his Travel Air Manufacturing Company at Wichita, Kansas, and he included flying lessons with her employment. Beech asked her to go to Oakland as an employee of Douglas C. Warren, the new Travel Air dealer for the western region of the United States. He included flying lessons with her employment. (Warren owned the airplanes used by Mrs. Thaden to set her altitude and endurance records.) She received her pilot’s license from the National Aeronautic Association, signed by Orville Wright, 16 May 1928.

Louise Thaden’s original pilot license, No. 6850, issued by the National Aeronautic Association and signed by Orville Wright. (The Central Arkansas Library System)

Miss McPhetridge married Mr. Herbert von Thaden at San Francisco, California, 21 July 1928. Thaden was a former military pilot and an engineer. They would have two children, William and Patricia.²

In 1929, Mrs. Thaden was issued Transport Pilot License number 1943 by the Department of Commerce. She was the fourth woman to receive an Airline Transport Pilot rating.

Mrs Thaden set an FAI World Record for Altitude of 6,178 meters (20,269 feet) over Oakland, California, 7 December 1928.¹  On 17 March 1929, she set an FAI record for duration of 22 hours, 3 minutes.²

Louise Thaden served as secretary of the National Aeronautic Association, and was a co-founder of The Ninety-Nines. She served as that organization’s vice president and treasurer. She set several world and national records and was awarded the national Harmon Trophy as Champion Aviatrix of the United States in 1936.

Louise Thaden stopped flying in 1938. She died at High Point, North Carolina, 9 November 1979.

Louise Thaden with her 1936 Vincent Bendix Trophy, circa 1975. (NASM)

¹ FAI Record File Number 12223

² Thaden had founded the Thaden Metal Aircraft Company, builder of the all-metal Thaden T-1, T-2, and T-4 Argonaut. He went on to design molded plywood furniture for the Thaden-Jordan Furniture Corporation. His designs are considered to be works of art, and individual pieces sell for as much as $30,000 today.

© 2019, Bryan R. Swopes

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10–11 February 1929

“Feb. 11, 1929: Evelyn “Bobbie” Trout, 23, standing beside her Golden Eagle airplane at Mines Field after setting women’s solo endurance flying record.” (Los Angeles Times Archive/UCLA)
“Feb. 11, 1929: Evelyn “Bobbie” Trout, 23, standing beside her Golden Eagle airplane at Mines Field after setting women’s solo endurance flying record.” (Los Angeles Times Archive/UCLA)

10–11 February 1929: At Mines Field, Los Angeles, California (now, Los Angeles International Airport—better known simply as LAX), Evelyn (“Bobbie”) Trout set a Fédération Aéronautique Internationale (FAI) World Record for Duration with an overnight endurance record of 17 hours, 5 minutes, while flying the prototype R. O. Bone Co. Golden Eagle Monoplane.¹

This was Bobbie Trout’s second FAI duration record. Her first, set at Metropolitan Field, Van Nuys, California, 2 January 1929, had been broken by Elinor Smith four weeks later. This record would also be broken, five weeks later—17 March 1929—by Louise Thaden.

The Los Angeles Times reported:

Evelyn Trout – a wisp of a woman in a wisp of an airplane – landed at Mines Field yesterday after having flown alone more hours and more miles continuously than any other woman in the world ever did before. Also, she is the first woman ever to fly through an entire night. She may have taken up the heaviest loaded sixty-horse-power plane that ever left the ground.

Miss Trout, Bobbie, as she is more generally known, took off at Mines Field Sunday at 5:10:15 p.m. She landed at the same place yesterday at 10:16:22 a.m. She was in the air 17 hours, 5 minutes and 37 seconds, Joe Nikrent, chief timekeeper, announced.

The flight, Dudley Steele, contest chairman of the National Aeronautical Association, said, was three hours and forty-eight minutes longer than the previous woman’s endurance record.

She flew, he said, approximately 860 miles. This, he pointed out, is not far under the world record hung up in Europe some time ago by a man who flew a plane in that class 932 miles over a charted course. Steele said her average speed was 50.292 miles per hours…

Miss Trout got out of the plane with but little more evidence of fatigue than if she had been up only a few hours.

“Hello mother,” she cried to Mrs. George E. Trout, who ran to embrace her.

“We’re awfully proud of you,” Mrs. Trout said.

“Thanks mother, dear,” Bobbie replied.

The young woman, who is 23 years of age, stretched herself and danced on first one foot and then the other.

“I need exercise,” she said, straightening out her cramped limbs.

She posed patiently for newspaper photographers and laughingly talked with any of the crowd of several hundred that was on the field to see her land. . . .

Los Angeles Times, 12 February 1929

Official timer Joseph A. Nikrent consults with Evelyn Trout, while Will Rogers looks on, at Mines Field, Los Angeles, California, 11 February 1929. (Unattibuted)

Having saved $2,500.00 for training, at the age of 22 Bobbie Trout began her flight lessons at the Burdett Air Lines School of Aviation at Los Angeles. She soloed four weeks later. On 21 January 1929, trout was awarded a pilot certificate by the National Aeronautic Association of the U.S.A, on behalf of the Fédération Aéronautique Internationale. Her license was carried by space shuttle pilot Lieutenant Colonel Eileen Marie Collins aboard Discovery (STS-63) in February 1995.

National Aeronautic Association Pilot’s Certificate No. 7027, signed by Orville Wright. (The Ninety-Nines)
National Aeronautic Association Pilot’s Certificate No. 7027, signed by Orville Wright. (The Ninety-Nines)

Evelyn Trout later wrote about her record flight:

Shortly after my First Solo Endurance Record on January 2, 1929 of 12 Hours–11 Minutes, it was bettered by 1 hour. My Boss, Mr. Bone had promised me that any time my record was broken he would help me better it.

His factory went to work making a larger gasoline tank. On February 9th the plane was standing on the south side of Mines Field (now LAX) while last preparations were in progress and Joe Nikrent (official timer) was standing on his head in my Golden Eagle putting the barograph in the fuselage. Of course plenty of mechanics, pilots, press writers, photographers, my family and public were there to watch Mr. Bone and me prepare for my 2nd Solo Endurance Flight Take-Off. This was about 4PM when I crawled up into the cockpit wearing my beautiful red sheep-wool lined coat with a huge Golden Eagle on the front, and my woolen breeches and boots to keep me warm. After I was in the seat, good luck items, food, and liquid were given to me to place where ever I could find room and get to them, which took some figuring. All seemed ready for the night.

Switch on and the prop was turned, after a few kisses from family and Mr. Bone I turned into position for take-off which soon saw me lift-off for a long grueling flight. The first half of the night was simple flying around the field and watching the cars disappear. As night grew longer and all below was quiet except for the Klieg lights that shone brightly and I would fly through the beams, then I became very sleepy “as I later learned that my system was lacking in protein,” I would sing, rub my neck, wiggle in the seat, rub around my helmet, pat my cheeks, peel tangerines and eat them, this continues on and on, sometimes I would find myself drifting off to sleep only to be awakened by the engine revving faster from a downward flying position which would frighten me enough to stay awake for a longer time. These actions were repeated over and over until the sun finally started to climb up and over the horizon. This seemed to give me a good lift to continue on my route which was around and around the field and sometimes over Inglewood, where I later found out that I had been keeping the residents awake. I would gain altitude when I wandered away from the field too far as to make a Record, the plane must return to the take-off field. After several hours planes were coming up with congratulations and all sorts of expressions because I had made a new record. I landed about 10AM. Little did I know or the press, or the factory and Mr. Bone, at this point, that I had made 6 records. We did know that I was the first Woman to fly all night and stay up 17 hours and 5 Minutes which did set a record for miles flown too, but it took time for the engineers to check that I with the 60 HP LeBlound [sic] engine had lifted off with a greater load for that 60 HP engine and later the sq. Feet of the wing, and another technicality.

A bed & home was all that I wanted now! — Evelyn Trout

Bobbie Trout with the prototype Golden Eagle Monoplane, 1929. (Davis-Monthan Airfield Register)
Bobbie Trout with the R.O. Bone Co. prototype Golden Eagle monoplane, NX522. The airplane has had a NACA engine cowling added for better cooling and decreased drag. (Davis-Monthan Aviation Field Register)

Evelyn Trout’s airplane, the prototype of the Bone Golden Eagle, serial number C-801, was designed by R.O. Bone and Mark Mitchell Campbell. It was a single-place, single-engine strut-braced high-wing (“parasol”) monoplane with fixed landing gear.

The Golden Eagle was 21 feet, 10 inches (6.655 meters) long with a wingspan of 30 feet, 5 inches (9.271 meters). Its empty weight was 800 pounds (363 kilograms) and gross weight was 1,350 pounds (612 kilograms).

The airplane was powered by an air-cooled, normally aspirated 250.576-cubic-inch-displacement (4.106 liter), LeBlond Aircraft Engine Corporation 60-5D five-cylinder radial engine, which had a compression ratio of 5.42:1. It was rated at 65 horsepower at 1,950 r.p.m., at Sea Level. The 60-5D was a direct-drive engine which turned a two-bladed propeller. The engine weighed 228 pounds (103 kilograms).

The Golden Eagle had a cruise speed of 80 miles per hour (129 kilometers per hour) and maximum speed of 95 miles per hour (153 kilometers per hour). The standard production model had a fuel capacity of 25 gallons (95 liters).

The prototype was assigned Experimental registration NX522, 3 May 1929. While being flown by Eddie Martin, NX522 was damaged beyond repair in an accident, 8 July 1929, at Los Angeles, California. The registration was cancelled 25 July 1929.

Astronaut Eileen Collins holds Bobbie Trout’s pilot certificate, 1995. (Unattributed)
Astronaut Eileen Collins holds Bobbie Trout’s pilot certificate, 1995. (Unattributed)

The production Golden Eagle was advertised as a very stable, “hands off” airplane. The asking price for the basic model was $2,790.00.

The R.O. Bone Company reorganized as the Golden Eagle Corporation but The Great Depression doomed the company. Only one Golden Eagle is believed to exist.

Evelyn Trout set several other flight records. Along with Amelia Earhart and several others she co-founded The Ninety-Nines, an international organization of women aviators. At the age of 97 years, she died at San Diego, California, 27 January 2003.

¹ FAI Record File Number 12220

© 2019, Bryan R. Swopes

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14–22 August 1932

Frances Marsalis and Louise Thaden, in the cockpit of the Curtiss Thrush, shortly before takeoff, 14 August 1932. The I.J. Fox Company sponsored their flight. (San Diego Air & Space Museum)

14–22 August 1932: Over an eight-day period, Iris Louise McPhetridge Thaden and Frances E. Carter Harrell Marsalis flew a Curtiss Thrush J, NR9142, over the Curtiss Airport ¹ at Valley Stream, New York. Their flight set a Fédération Aéronautique Internationale (FAI) World Record for Duration of 196 hours, 5 minutes. ²

The pair took off at 1:00 p.m., Sunday, 14 August, and did not land until 5:06 p.m., Monday, 22 August. Newspaper reports at the time were that the total duration was 196 hours, 5 minutes “and four-fifths seconds.”

Their flight was supported by air-to-air refueling. A Curtiss Robin C-1, NR82H, flown by Stewart Reiss and John Runger, acted as the tanker. Seventy-eight in-flight refuelings were required to keep the Thrush airborne.

Curtiss Robin C-1 NR82H refueling Curtiss Thrush NR9142, August 1932.

The “two 24-year-old housewives” were sponsored by the I.J. Fox store on 5th Avenue, New York City, which was owned by philanthropist Isidore Joseph Fox, “America’s Largest Furrier.” Mrs. Fox was an aviation enthusiast who often attended races and other events, and provided prizes. The Thrush had “I.J. FOX” boldly painted on each side of its fuselage, with a smaller name and the company’s fox head logo on the forward doors.

Curtiss Thrush J NC9142 at Floyd Bennett Field. (William F. Yeager Collection, Wright State University ms223_041_043)

NR9142 was the first protototype Curtiss Thrush, s/n G-3. It was initially registered NX9142. In preparation for the endurance flight, the interior had been stripped of the passengers seats and carpet. A 150 gallon (568 liters) auxiliary fuel tank was installed.

The Curtiss Thrush was a single-engine six-place high-wing cabin monoplane with fixed landing gear. It was 32 feet, 7 inches (9.931 meters) long with a wingspan of 48 feet, 0 inches (14.630 meters) and overall height of 9 feet, 3 inches (2.819 meters). The wing had a chord of 7 feet, 0 inches (2.134 meters). The airplane’s empty weight was 2,260 pounds (1,025 kilograms), and its gross weight was 3,800 pounds (1,724 kilograms).

Curtiss Thrush NX9142 with Curtiss Challenger R600-6 engine and cowling; unknown pilot. Compare the early vertical fin and rudder to those in the photograph of NC9142, above. (Curtiss Aeroplane and Motor Company)

The Curtiss Thrush was initially powered by an air-cooled, normally-aspirated, 603.397 cubic-inch-displacement (9.888 liters) Curtiss Challenger R600–6, two-row, 6-cylinder radial engine with a compression ratio of 5.2:1. The engine was rated at 185 horsepower at 2,000 r.p.m. with 65-octane gasoline. The direct-drive engine turned a Curtiss-Reed fixed-pitch propeller, and later, a Turnbull variable-pitch propeller. The R600-6 was 42.63 inches (1.083 meters) long, 41.75 inches (1.060 meters) in diameter, and weighed 445 pounds (202 kilograms).

The second prototype Curtiss Thrush, NX9787, with Challenger R600-6 engine. (NASM-CW8G-T-6172 2)

During flight testing, the Challenger-powered Thrush was disappointingly underpowered. The Curtiss engine was replaced with a Wright J6E Whirlwind, and the airplane designated Thrush J. The J6E, or Wright R-760E Whirlwind 250, was an air-cooled, supercharged, 755.95 cubic inch (12.39 liters) seven-cylinder radial engine with a compression ratio of 5.1:1. It was rated at 250 horsepower at 2,000 r.p.m. at Sea Level for takeoff (1-minute limit) and required 73-octane gasoline. This was also a direct-drive engine. The R-760E weighed 530 pounds (240 kilograms)

Curtiss Thrush prototype wit Wright Whirlwind engine (NASM-CW8G-T-4842-neg

The Curtiss Thrush J had a cruise speed of 104 miles per hour (167 kilometers per hour) and maximum speed of 122 miles per hour (196 kilometers per hour). Its service ceiling was 13,200 feet (4,023 meters) and it had a range of 900 miles (1,448 kilometers).

Thirteen Curtiss Thrush Js were built.

Stewart Reiss (left) and John Runger with air tanker Curtiss Robin C-1 NR82H. (Fédération Aéronautique Internationale)
John Runger, Thaden, Charles S. “Casey” Jones, Curtiss airport manager, Marsalis, Stewart Reiss, post flight (AP)

¹ Formerly Advance Sunrise Airport, purchased by Curtiss 1929; closed 1934.

² FAI Record File Number 12347

© 2018, Bryan R. Swopes

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12 June 1979

Bryan Allen flies Gossamer Albatross across the English Channel.
Bryan Allen flies Gossamer Albatross across the English Channel. (Don Monroe via Bryan Allen)

12 June 1979: The human-powered airplane, Gossamer Albatross, built by AeroVironment, Inc., of Simi Valley, California, flew across the English Channel from The Warrens, near Folkstone, Kent, England, to Cap Griz-Nez, France, 22.26 miles (35.82 kilometers) in 2 hours, 49 minutes. He established two Fédération Aéronautique Internationale (FAI) World Record: Straight Distance, 35.82 kilometers (22.26 miles)¹ ; Duration, 2 hours, 49 minutes.²

The pilot/powerplant of Gossamer Albatross was long-distance bicyclist Bryan Lewis Allen. Allen pedaled at a constant 75 r.p.m.

Bryan Lewis and Paul Macready, London, 16 May 1979. (Getty Images/United News/Popperfoto)
Bryan Lewis and Paul MacCready, London, 16 May 1979. (Getty Images/United News/Popperfoto)
Gossamer Albatross arrives at France, 12 June 1978. (AeroEnvironment)
Gossamer Albatross arrives at France, 12 June 1978. (AeroEnvironment, Inc.

The aircraft was designed by Paul Beattie MacCready, Jr., Ph.D., and weighed just 70 pounds (31.8 kilograms), empty.

The two-way radio link failed right after takeoff. Unexpected winds made the flight an hour longer than planned and Allen used all of his water. Batteries powering the instruments ran down. A chase boat was prepared for Allen to abort the flight, but he continued to France.

Bryan Lewis Allen was born 13 October 1952 at Tulare, California. He attended Tulare Union High School and then College of the Sequoias and California State University, Bakersfield, earning a bachelor of science degree. Allen is employed as a software engineer for the Mars Reconnaissance Orbiter at the NASA Jet Propulsion Laboratory, Pasadena, California.

Paul Beattie MacCready, Jr., was born 29 September 1925. He graduated from Yale University with a bachelor’s degree in physics, and then earned a master’s in physics from the California Institute of Technology, Pasadena, California. In 1952, Caltech awarded MacReady a doctorate in aeronautics.

The Robert J. Collier Trophy. (Smithsonian Institution, National Air and Space Museum)
The Robert J. Collier Trophy. (Smithsonian Institution, National Air and Space Museum)

Dr. MacReady received the Collier Trophy for 1979 from the National Aeronautic Association, “For the concept, design and construction of the Gossamer Albatross, which made the first man-powered flight across the English Channel—with special recognition to Bryan Allen, the pilot.”

Dr. Paul B. MacReady died 25 August 2007 at Pasadena, California.

The Gossamer Albatross is a human-powered high-wing canard monoplane constructed primarily of carbon fiber tubing, expanded polystyrene foam, Mylar® and Kevlar®, with wire bracing. A single pilot in a gondola provides power to a two-bladed fixed-pitch propeller, pedaling at 75 r.p.m., through a bicycle-type gear-reduction drive mechanism.

The airplane is 50 feet, 6 inches (15.392 meters) long, with a wingspan of 93 feet, 10 inches (28.600 meters) and overall height of 16 feet, 4 inches (4.978 meters). It has an empty weight of 70 pounds (31.8 kilograms), and a gross weight at takeoff of 215 pounds (97.5 kilograms). Its maximum speed is 15 miles per hour (24 kilometers per hour).

Three-view drawing of Gossamer Albatross. (Natural Flight Foundation)

Gossamer Albatross is in the collection of the Stephen F. Udvar-Hazy Center, Smithsonian Institution National Air and Space Museum.

Gossamer Albatross at teh National Air and Space Museum. (NASM)
Gossamer Albatross at the National Air and Space Museum. (NASM)

¹ FAI Record File Number 392

² FAI Record File Number 393

© 2017, Bryan R. Swopes

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6 May 1941

Igor Sikorsky with his VS-300A, Stratford, Connecticut, 6 May 1941. (Sikorsky Archives)

6 May 1941: At Stratford, Connecticut, Igor Sikorsky piloted his Vought-Sikorsky VS-300 helicopter to a new world’s record for endurance. He flew for 1 hour, 32 minutes, 26 seconds. ¹ The previous record—1 hour, 20 minutes, 49 seconds—had been set by Ewald Rohlfs with the Focke-Wulf Fw 61 tandem-rotor helicopter, 25 June 1937. ²

During its development, the VS-300 went through at least 18 changes in its rotor configuration. This photograph, taken after the record-setting flight, shows an intermediate version, with one main rotor for lift and three auxiliary rotors for anti-torque and directional control.

Igor Ivanovich Sikorsky 1888–1970. Sikorsky Archives)

In the final configuration, Sikorsky arrived at what we now recognize as a helicopter, with the main rotor providing lift, thrust and roll control through variable collective and cyclic pitch, and a single tail rotor for anti-torque and yaw control.

The VS-300 had a welded tubular steel airframe and used a 28-foot (5.34 meters) diameter, fully-articulated, three-bladed main rotor, which turned clockwise (as seen from above) at 260 r.p.m. (The advancing blade was on the left. This would later be reversed.) The main rotor had collective pitch control for vertical control, but cyclic pitch (Sikorsky referred to this as “sectional control”) for directional control would not be developed for another several months.

The tail “propellers” (what we now consider to be rotors—one vertical and two horizontal) each had two blades with a diameter of 7 feet, 8 inches (2.337 meters) and turned approximately 1,300 r.p.m. The vertical rotor provided “torque compensation” (anti-torque) and the blade pitch was fully reversible. The horizontal rotors were mounted on 10-foot (3.048 meters) outriggers at the aft end of the fuselage. For lateral control, the pitch on one rotor was increased and the other decreased. For longitudinal control, the pitch of both rotors was increased or decreased together.

The VS-300 was originally equipped with an air-cooled, normally-aspirated 144.489-cubic-inch-displacement (2.368 liter) Lycoming O-145C-3 four-cylinder horizontally-opposed engine which was rated at 75 horsepower at 3,100 r.p.m. According to Mr. Sikorsky, “early in 1941,” the Lycoming engine was replaced by an air-cooled, normally-aspirated 198.608 cubic inch (3.255 liter) Franklin 4AC-199-E, a four-cylinder horizontally-opposed overhead valve (OHV) direct-drive engine with a compression ratio of 7:1, rated at 90 horsepower at 2,500 r.p.m. It is not known if this change was made prior to 6 May.

¹ During World War II, only a very few ballooning and gliding world records were certified by the Fédération Aéronautique Internationale. Although Sikorsky’s flight duration exceeded that of Rohlfs, it is not listed as an official world record.

² FAI Record File Number 13147

© 2019, Bryan R. Swopes

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