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.
4 May 1924: At 7:30 a.m., Étienne Edmond Oehmichen (1884–1955), an engineer for Société Anonyme des Automobiles et Cycles Peugeot, flew his four-rotor L’Hélicoptère Nº2 around a triangular closed circuit of approximately 1 kilometer (0.62 mile) at Valentigney, France. The flight took 7 minutes, 40 seconds. It was observed by the public, members of the press and officials of the Service Technique de l’ Aéronautique (S.T.Aé, the French air ministry). For his accomplishment, Oehmichen was awarded a prize of ₣90,000 by the government of France.
FLIGHT reported:
A Fresh Helicopter Record
M. Oemichen has been continuing his experiments at Valentigny with his helicopter, and on Sunday, May 4, established a record for helicopters by accomplished a flight of more than one kilometre—1,100 yards—in a closed circuit. The flight lasted 7 mins. 40 secs. and during most of the time the machine maintained a height of about 3 feet, but sometimes rose to 10 feet. The flight was officially observed by a representative of the Department of Military Aeronautics. By this performance M. Oemichen wins an award of 90,000 francs given by the French Government.
FLIGHT, The Aircraft Engineer & Airships, No. 802 (No. 19, Vol. XVI.) May 8, 1924, Page 267, Column 1
The previous month, Oehmichen had set two FAI world rotorcraft records for distance in a straight line. On 14 April 1924, he flew 360 meters (1,181 feet)¹, and on 17 April, 525 meters (1,722 feet).²
On 14 September 1924, he would set two records for altitude, 1 meter (3.28 feet) with a 100 kilogram (220 pounds) and a 200 kilogram (441 pounds) payload.³
One of the configurations of Oemichen’s helicopter.
Oehmichen’s helicopter (also referred to by some sources as the Peugeot Nº2) was a cross-shaped structure built of metal tubing. Lift was generated by four two-bladed, counter-rotating, main rotors. Two rotors had a diameter of 6.5 meters (21 feet, 4 inches), and the other two, 7.5 meters (24 feet, 7 inches). They all turned at 145 r.p.m. Blade pitch was controlled by warping.
The helicopter had another five rotors positioned in the horizontal plane. Three had a diameter of 1.45 meters (4 feet, 9 inches), and two, 1.55 meters (5 feet, 1 inch). These had reversible pitch were used to provide lateral control. Two variable-pitch pusher propellers with a diameter of 1.40 meters (4 feet, 7 inches) were positioned on each side of the lateral structure, and were driven by belts. The helicopter was steered by another small rotor at the front.
“Ensemble perspectif sçhématique des sustentateurs, propulseurs et évoluers de l’hélicoptère Oemichen-Peogeot Nº 2.” (L’Aéronautique, 6me Année. Nº 61, Juin 1924, at Page 138)
With the helicopter having an operating weight of approximately 1,000 kilograms (2,205 pounds), the rotors had a load factor of 33 kilograms per square meter (6.8 pounds per square foot).
L’hélicoptère Nº2 was powered by a single Société des Moteurs Gnome et Rhône Type R nine-cylinder rotary engine placed vertically near the center of the structure.
The Le Rhône Type R, introduced in 1917, was an air-cooled, normally-aspirated, 15.892 liter (969.786 cubic inches) nine-cylinder overhead valve rotary engine with two valves per cylinder. The Type R produced 170 cheval vapeur (167.7 horsepower) at 1,360 r.p.m. The engine was 0.990 meters (3 feet, 2.9 inches) long, 0.995 meters (3 feet, 3.2 inches) in diameter, and weighed 166 kilograms (366 pounds).
Étienne Oehmichen’s Helicopter No. 2, 4 May 1924.
¹ FAI Record File Number 13093
² FAI Record File Number 13095
³ FAI Record Files 13091 (100 kilograms) and 13092 (200 kilograms)
Lieutenants John A. Macready and Oakley G. Kelly with their Fokker T-2. (NASM)Captain John A. Macready, Air Service, United States Army. (U.S. Air force)
2–3 May 1923: Air Service, United States Army, pilots Lieutenant John Arthur Macready and Lieutenant Oakley George Kelly made the first non-stop transcontinental flight. Their airplane was a Nederlandse Vliegtuigenfabriek Fokker T-2 single-engine monoplane, U.S. Army serial number A.S. 64233.
The two aviators took off from Roosevelt-Hazelhurst Field, Long Island, New York, at 12:30 p.m., Eastern Time, and landed at Rockwell Field (now, NAS North Island), San Diego, California, the next day at 12:26 p.m., Pacific Time. They had flown 2,470 miles (3,975 kilometers) in 26 hours, 50 minutes, 38.8 seconds, for an average speed of 91.996 miles per hour (148.053 kilometers per hour).
Macready and Kelly had made two previous attempts, flying West-to-East to take advantage of prevailing winds and the higher octane gasoline available in California. The first flight was terminated by weather, and the second by engine failure.
Fokker T-2 A.S. 64233 (FAI)
The Fokker F.IV was built by Anthony Fokker’s Nederlandse Vliegtuigenfabriek at Veere, Netherlands, in 1921. The Air Service purchased two and designated the type T-2, with serial numbers A.S. 64233 and A.S. 64234.
Several modifications were made to prepare the T-2 for the transcontinental flight. Normally flown by a single pilot in an open cockpit, a second set of controls was installed so that the airplane could be controlled from inside while the two pilots changed positions. Additional fuel tanks were installed in the wing and cabin.
Fokker T-2 A.S. 64233. (Sally M. Macready Foundation Collection/NASM)
The Fokker F.IV was a single-engine, high-wing monoplane with fixed landing gear. It was flown by a single pilot in an open cockpit which was offset to the left of the airplane’s centerline. The airplane was designed to carry 8–10 passengers in an enclosed cabin. The F.IV was a scaled-up version of the preceding F.III. It was built of a welded tubular steel fuselage, covered with three-ply plywood. The wing structure had plywood box spars and ribs, and was also covered with three-ply plywood.
For its time, the Fokker was a large airplane. Measurements from the Fokker T-2 at the Smithsonian Institution are: 49 feet, 10 inches (15.189 meters) long, with a wing span of 80 feet, 5 inches (24.511 meters), and height 12 feet, 2 inches (3.708 meters). On this flight, it carried 735 gallons (2,782 liters) of gasoline in three fuel tanks. When it took off from Long Island, the gross weight of the T-2 was 10,850 pounds (4,922 kilograms), only a few pounds short of its maximum design weight.
Fokker T-2, A.S. 64223. (The biplane is a Verville-Sperry M-1.) (Harris & Ewing)
The Fokker F.IV was offered with a choice of engines: A Rolls-Royce Eagle IX V-12, Napier Lion II “broad arrow” W-12, or Liberty L-12 V-12. The T-2 was powered by a water-cooled, normally-aspirated, 1,649.336-cubic-inch-displacement (27.028 liter) Ford-built Liberty L-12 single overhead cam (SOHC) 45° V-12 engine with a compression ratio of 5.4:1. (Serial number A.S. No. 5142) The Liberty produced 408 horsepower at 1,800 r.p.m. The L-12 as a right-hand tractor, direct-drive engine. Installed on A.S. 64233, the engine turned turned a two-bladed Curtiss fixed-pitch walnut propeller with a diameter of 10 feet, 5 inches (3.175 meters). The Liberty 12 was 5 feet, 7.375 inches (1.711 meters) long, 2 feet, 3.0 inches (0.686 meters) wide, and 3 feet, 5.5 inches (1.054 meters) high. It weighed 844 pounds (383 kilograms).
First Lieutenant Oakley G. Kelly, U.S. Army Air Service (FAI)
John Macready and Oakley Kelley won the 1923 Mackay Trophy for this flight. Macready had previously won the award in 1921 and 1922. He is the only pilot to have won it three times.
During testing to determine the feasibility of the flight, on 16–17 April 1923, Lieutenant Kelly and Lieutenant Macready set six Fédération Aéronautique Internationale (FAI) World Records for speed, distance and duration, flying the Fokker T-2. At Wilbur Wright Field, Dayton, Ohio, they flew 2,500 kilometers (1,553.428 miles) at an average speed of 115.60 kilometers per hour (51.83 miles per hour); 3,000 kilometers (1,864.114 miles) at 115.27 kilometers per hour (71.63 miles per hour); 3,500 kilometers (2,174.799 miles) at 114.82 kilometers per hour (71.35 miles per hour); 4,000 kilometers (2,485.485 miles) at 113.93 kilometers per hour (70.79 miles per hour); flew a total distance of 4,050 kilometers (2,517 miles); and stayed aloft for 36 hours, 4 minutes, 34 seconds. Their overall average speed was 112.26 kilometers per hour (69.76 miles per hour) seconds.
The United States Army transferred Fokker T-2 A.S. 64223, to the Smithsonian Institution in January 1924. It is on display at the National Air and Space Museum.
U.S. Army Air Service Fokker T-2, A.S. 64233, on display at the Smithsonian Institution, National Air and Space Museum. (NASM)
Lockheed YF-12A 60-6936, flies test mission near Edwards Air Force Base, Califrnia. (U.S. Air Force)
1 May 1965: Lockheed YF-12A 60-6936 established five Fédération Aéronautique Internationale (FAI) World Records for Speed: 3,351.507 kilometers per hour (2,070.102 m.p.h.) over a 15/25 Kilometer Straight Course; 2,644.22 kilometers per hour (1,643.04 miles per hour) over a 500 Kilometer Closed Circuit; and 2,718.01 kilometers per hour (1,688.89 miles per hour) over a 1,000 Kilometer Closed Circuit. On the same day, 6936 set an FAI World Record for Altitude in Horizontal Flight of 24,463 meters (80,259 feet).
The World Record-setting flight crews, from left to right, Captain James P. Cooney, Major Walter F. Daniel, Colonel Robert L. Stephens, Lieutenant Colonel Daniel Andre and Major Neil T. Warner. (U.S. Air Force)
The YF-12A interceptor prototype was flown by pilots Major Walter F. Daniel and Colonel Robert L. Stephens, with fire control officers Lieutenant Colonel Daniel Andre, Major Neil T. Warner and Captain James P. Cooney. Colonel Stephens and Lieutenant Colonel Andre were awarded the Thompson Trophy for the “J” Division, 1965. Their trophy is in the collection of the National Museum of the United States Air Force.
Lockheed YF-12A 60-6936 taking off from Edwards Air Force Base during the speed record trials, 1 May 1965. The white cross on the aircraft’s belly was to assist timers and observers. (U.S. Air Force)
FAI Record File Num #3972 [Direct Link]
Status: ratified – retired by changes of the sporting code
Region: World
Class: C (Powered Aeroplanes)
Sub-Class: C-1 (Landplanes)
Category: Not applicable
Group: 3 : turbo-jet
Type of record: Speed over a closed circuit of 1 000 km with 1 000 kg payload
Performance: 2 718.01 km/h
Date: 1965-05-01
Course/Location: Edwards AFB, CA (USA)
Claimant Walter F. Daniel (USA)
Aeroplane: Lockheed YF-12A (06936)
Engines: 2 Pratt & Whitney J-58/JTD11D-20A
FAI Record File Num #3973 [Direct Link]
Status: ratified – retired by changes of the sporting code
Region: World
Class: C (Powered Aeroplanes)
Sub-Class: C-1 (Landplanes)
Category: Not applicable
Group: 3 : turbo-jet
Type of record: Speed over a closed circuit of 1 000 km with 2 000 kg payload
Performance: 2 718.01 km/h
Date: 1965-05-01
Course/Location: Edwards AFB, CA (USA)
Claimant Walter F. Daniel (USA)
Aeroplane: Lockheed YF-12A (06936)
Engines: 2 Pratt & Whitney J-58/JTD11D-20A
FAI Record File Num #8534 [Direct Link]
Status: ratified – retired by changes of the sporting code
Region: World
Class: C (Powered Aeroplanes)
Sub-Class: C-1 (Landplanes)
Category: Not applicable
Group: 3 : turbo-jet
Type of record: Altitude in horizontal flight
Performance: 24 463 m
Date: 1965-05-01
Course/Location: Edwards AFB, CA (USA)
Claimant R.L. Stephens (USA)
Aeroplane: Lockheed YF-12A
Engines: 2 Pratt & Whitney J-58/JTD11D-20A
FAI Record File Num #8855 [Direct Link]
Status: ratified – retired by changes of the sporting code
Region: World
Class: C (Powered Aeroplanes)
Sub-Class: C-1 (Landplanes)
Category: Not applicable
Group: 3 : turbo-jet
Type of record: Speed over a closed circuit of 500 km without payload
Performance: 2 644.22 km/h
Date: 1965-05-01
Course/Location: Edwards AFB, CA (USA)
Claimant Walter F. Daniel (USA)
Aeroplane: Lockheed YF-12A
Engines: 2 Pratt & Whitney J-58/JTD11D-20A
FAI Record File Num #8926 [Direct Link]
Status: ratified – retired by changes of the sporting code
Region: World
Class: C (Powered Aeroplanes)
Sub-Class: C-1 (Landplanes)
Category: Not applicable
Group: 3 : turbo-jet
Type of record: Speed over a closed circuit of 1 000 km without payload
Performance: 2 718.006 km/h
Date: 1965-05-01
Course/Location: Edwards AFB, CA (USA)
Claimant Walter F. Daniel (USA)
Aeroplane: Lockheed YF-12A
Engines: 2 Pratt & Whitney J-58/JTD11D-20A
FAI Record File Num #9059 [Direct Link]
Status: ratified – retired by changes of the sporting code
Region: World
Class: C (Powered Aeroplanes)
Sub-Class: C-1 (Landplanes)
Category: Not applicable
Group: 3 : turbo-jet
Type of record: Speed over a straight 15/25 km course
Performance: 3 331.507 km/h
Date: 1965-05-01
Course/Location: Edwards AFB, CA (USA)
Claimant R.L. Stephens (USA)
Aeroplane: Lockheed YF-12A
Engines: 2 Pratt & Whitney J-58/JTD11D-20A
World Speed Record holders and Thompson Trophy winners, Colonel Robert L. Stephens and Lieutenant Colonel Daniel Andre. (U.S. Air Force)
60-6936 was one of three Mach 3 YF-12A interceptors designed and built by Kelly Johnson’s “Skunk Works”. It was developed from the CIA’s Top Secret A-12 Oxcart reconnaissance airplane. The YF-12A was briefly known as the A-11, which was a cover story to hide the existence of the A-12. Only three were built. The Air Force ordered 93 F-12B interceptors into production as a replacement for the Convair F-106A Delta Dart, but for three straight years Secretary of Defense Robert S. McNamara refused to release the funds that had been appropriated. In 1968, the F-12B project was cancelled.
On 24 June 1971, 60-6936 suffered an in-flight fire while on approach to Edwards Air Force Base. The crew successfully ejected and the airplane crashed a few miles to the north of EDW. It was totally destroyed.
The only surviving example of a YF-12A, 60-6935, is in the collection of the National Museum of the United States Air Force.
The 1965 Thompson Trophy on display at the National Museum of the United States Air Force. (U.S. Air Force)
Jackie Cochran with the Lockheed TF-104G Starfighter, N104L. (FAI)
1 May 1963: At Edwards Air Force Base, California, Jacqueline (“Jackie”) Cochran, Colonel, U.S. Air Force Reserve, established a Fédération Aéronautique Internationale (FAI)World Speed Record when she flew this two-place Lockheed TF-104G Starfighter, FAA registration N104L, named Free World Defender, over a 100-kilometer (62.137-mile) closed circuit at an average speed of 1,937.15 kilometers per hour (1,203.69 miles per hour).¹
Jackie Cochran wrote about flying the 100-kilometer course in her autobiography:
The 100 kilometer closed course was so damn difficult. Imagine an absolutely circular racetrack, about a quarter of a mile wide, on the ground with an inner fence exactly 63 miles long. Now, in your mind’s eye, leave the track and get into the air at 35,000 feet. Fly it without touching the fence in the slightest. It’s tricky because if you get too far away from the inner fence, trying not to touch, you won’t make the speed you need to make the record. And if you get too close, you’ll disqualify yourself.
Eyes are glued to the instrument panel. Ears can hear the voice of the space-positioning officer. You are dealing in fractions of seconds. And your plane isn’t flying in flat position. It’s tipped over to an 80-degree bank to compensate for the circle. That imaginary inner fence may be to your left, but you don’t head your plane left. That’d lose altitude. Instead, you pull the nose up a bit and because the plane is so banked over, you move closer to the fence. You turn.
—Jackie Cochran: An Autobiography, by Jacqueline Cochran and Maryann Bucknum Brinley, Bantam Books, New York 1987, Page 314.
She had flown this same F-104 to an earlier speed record at Edwards Air Force Base, 12 April 1963.
N104L was retained by Lockheed for use as a customer demonstrator to various foreign governments. In 1965 Lockheed sold N104L to the Dutch Air Force, where it served as D-5702 until 1980. It next went to the Turkish Air Force until it was retired in 1989.
Lockheed TF-104G Starfighter N104L, World Speed Record holder. (Lockheed)