20 May 1967

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Colonel Robin Olds, United States Air Force

20 May 1967: Colonel Robin Olds, USAF, commanding officer of the 8th Tactical Fighter Wing based at Ubon Rachitani Royal Thai Air Force Base, and Weapons System Officer 1st Lieutenant Stephen B. Croker, destroyed two Vietnam People’s Air Force MiG-17 fighters with AIM-7 Sparrow radar-guided and AIM-9 Sidewinder heat-seeking air-to-air missiles while flying McDonnell F-4C-24-MC Phantom II, serial number 64-0829, named SCAT XXVII.

An official U.S. Air Force history publication describes the air battle:

Two other MiG-17s became the victims of Col. Robin Olds and his pilot, 1st. Lt. Stephen B. Croker. [Note: at this point in time, the WSOs of USAF F-4Cs were fully-rated pilots.—TDiA] These were aerial victories three and four for Olds, making him the leading MiG-killer at that time in Southeast Asia. An ace from World War II, the 8th TFW commander was battle-tested and experienced. Olds termed the events of 20 May “quite a remarkable air battle.” According to his account:

F-105s were bombing along the northeast railroad; we were in escort position, coming in from the Gulf of Tonkin. We just cleared the last of the low hills lying north of Haiphong, in an east-west direction, when about 10 or 12 MiG-17s came in low from the left and, I believe, from the right. They tried to attack the F-105s before they got to the target.

Mikoyan Gurevich MiG-17F in Vietnam Peoples' Air Force markings at the National Museum of the United States Air Force, Wright-Patterson Air Force Base, Ohio. (U.S. Air Force).
Mikoyan Gurevich MiG-17F in Vietnam People’s Air Force markings at the National Museum of the United States Air Force, Wright-Patterson Air Force Base, Ohio. (U.S. Air Force).

We engaged MiG-17s at approximately 15 miles short of the target. The ensuing battle was an exact replica of the dogfights in World War II.

Our flights of F-4s piled into the MiGs like a sledge hammer, and for about a minute and a half or two minutes that was the most confused, vicious dogfight I have ever been in. There were eight F-4Cs, twelve MiG-17s, and one odd flight of F-105s on their way out from the target, who flashed through the battle area.

Quite frankly, there was not only danger from the guns of the MiGs, but the ever-present danger of a collision to contend with. We went round and round that day with the battles lasting 12 to 14 minutes, which is a long time. This particular day we found that the MiGs went into a defensive battle down low, about 500 to 1,000 feet. In the middle of this circle, there were two or three MiGs circling about a hundred feet—sort of in figure-eight patterns. The MiGs were in small groups of two, three, and sometimes four in a very wide circle. Each time we went in to engage one of these groups, a group from the opposite side would go full power, pull across the circle, and be in firing position on our tails almost before we could get into firing position with our missiles. This was very distressing, to say the least.

The first MiG I lined up was in a gentle left turn, range about 7,000 feet. My pilot achieved a boresight lock-on, went full system, narrow gate, interlocks in. One of the two Sparrows fired in ripple guided true and exploded near the MiG. My pilot saw the MiG erupt in flame and go down to the left.

Colonel Robin Olds flew this McDonnell F-4C-24-MC Phantom II, 64-0829, SCAT XXVII, when he and 1st Lieutenant Stephen B. Croker shot down two VPAF MiG-17s near Haiphong, North Vietnam, 20 May 1967. (U.S. Air Force)
Colonel Robin Olds flew this McDonnell F-4C-24-MC Phantom II, 64-0829, SCAT XXVII, when he and 1st Lieutenant Stephen B. Croker shot down two VPAF MiG-17s near Haiphong, North Vietnam, 20 May 1967. (U.S. Air Force)

We attacked again, trying to break up that defensive wheel. Finally, once again, fuel considerations necessitated departure. As I left the area by myself, I saw that lone MiG still circling and so I ran out about ten miles and said that even if I ran out of fuel, he is going to know he was in a fight. I got down on the deck, about 50 feet, and headed right for him. I don’t think he saw me for quite a while. But when he did, he went mad, twisting, turning, dodging and trying to get away. I kept my speed down so I wouldn’t overrun him and I stayed behind him. I knew he was either going to hit that ridge up ahead or pop over the ridge to save himself. The minute he popped over I was going to get him with a Sidewinder.

I fired one AIM-9 which did not track and the MiG pulled up over the ridge, turned left and gave me a dead astern shot. I obtained a good growl. I fired from about 25 to 50 feet off the grass and he was clear of the ridge by only another 50 to 100 feet when the Sidewinder caught him.

The missile tracked and exploded 5 to 10 feet to the right side of the aft fuselage. The MiG spewed pieces and broke hard left and down from about 200 feet. I overshot and lost sight of him.

I was quite out of fuel and all out of missiles and pretty deep in enemy territory all by myself, so it was high time to leave. We learned quite a bit from this fight. We learned you don’t pile into these fellows with eight airplanes all at once. You are only a detriment to yourself.

— Aces and Aerial Victories: The United States Air Force in Southeast Asia 1965–1973, by R. Frank Futrell, William H. Greenhalgh, Carl Grubb, Gerard E. Hasselwander, Robert F. Jakob and Charles A. Ravenstein, Office of Air Force History, Headquarters USAF, 1976, Chapter II  at Pages 59–60.

Coloenl Robin Olds, 8th Tactical Fighter Wing, with SCAT XXVII, his McDonnell F-4C-24-MC Phantom II, 64-0829, at Ubon Rachitani RTAFB, 1967. U.S. Air Force)
Colonel Robin Olds, 8th Tactical Fighter Wing, with SCAT XXVII, his McDonnell F-4C-24-MC Phantom II, 64-0829, at Ubon Rachitani RTAFB, 1967. U.S. Air Force)
Fighter pilot Brigadier General Robin Olds, U.S. Air Force (Retired) with SCAT XXVII at the National Museum of the United States Air Force. General Olds died 14 June 2007. (U.S. Air Force)
Fighter pilot Brigadier General Robin Olds, U.S. Air Force (Retired) with SCAT XXVII at the National Museum of the United States Air Force. General Olds died 14 June 2007. (U.S. Air Force) 
Robin Olds’ McDonnell F-4C-24-MC Phantom II, 64-0829, SCAT XXVII, at the National Museum of the United States Air Force, Wright-Patterson Air Force Base, Dayton, Ohio.

© 2016, Bryan R. Swopes

20 May 1948

Aviation, , , , ,
North American Aviation P-86A-1-NA Sabre 47-605, the first production aircraft. (U.S. Air Force)

20 May 1948: The first production North American Aviation, Inc., P-86A-1-NA, 47-605, made its first flight.

The P-86A-1-NA was very similar to the three XP-86 prototypes. As an operational fighter, its empty weight increased 347 pounds to 10,077 pounds. The Chevrolet J35-C-3 and Allison J35-A-5 engines were replaced with a more powerful General Electric J47-GE-1. The fighter’s maximum speed increased 74 miles per hour to 673 miles per hour at Sea Level.

The P-86 was unlike any airplane before it. (The designation was changed to F-86 the following month.) It was the first airplane produced with a swept wing. After analyzing World War II test data for the Messerschmitt Me 262, North American’s engineers designed a wing with a 35° degree sweepback to its leading edge. The wing sweep allowed high speed shock waves to form without stalling the entire wing. The wing tapered toward the tips, and its thickness also decreased from the root to the tip. In order to create a very strong but very thin wing, it was built with a two-layered aluminum skin, instead of ribs and spars, with each layer separated by “hat” sections. The thickness of the skin panels also tapered to decrease weight.

Cutaway illustration XP-86 concept. The side speed brakes were altered in production and the ventral brake eliminated. (North American Aviation, Inc.)

The wing  incorporated leading edge “slats” which were airfoil sections that automatically extended below 290 knots, smoothing the air flow over the wing’s upper surface and creating more lift at slow speeds. Above that speed, aerodynamic forces closed the slats, decreasing drag and allowing for higher speeds. Effectively, the wing could change its shape in flight.

Like the XP-86, the P-86A was 37 feet, 6.5 inches (11.443 meters) long with a wingspan of 37 feet, 1.4 inches (11.313 meters) and overall height of 14 feet, 8.9 inches (4.493 meters). The empty weight was 10,077 pounds (4,571 kilograms), gross weight, 14,050 pounds (6,373 kilograms) and maximum takeoff weight was 15,876 pounds (7,201 kilograms).

The J47-GE-1 was an axial-flow turbojet with a 12-stage compressor, 8 combustion chambers, and single stage turbine. It had a normal power rating of 4,320 pounds of thrust (19.216 kilonewtons) at 7,370 r.p.m.; and military power, 5,200 pounds (23.131 kilonewtons) at 7,950 r.p.m. (30-minute limit).

The P-86A had an initial rate of climb 7,470 feet per minute (37.95 meters per second) and could reach 40,000 feet (12,192 meters) in 10 minutes, 24 seconds. Its service ceiling was 48,000 feet (14,630 meters).

North American Aviation F-86A-5-NA 48-273. Note the gun port doors on this early production aircraft. They opened in 1/20 second as the trigger was pressed. Proper adjustment was complex and they were soon eliminated. (U. S. Air Force)

The Sabre was armed with six Browning AN-M3 .50-caliber aircraft machine guns placed in the nose, with three on either side of the engine intake. These were lighter and had a higher rate of fire than the World War II AN-M2 machine guns. Ammunition containers had a capacity of 300 rounds, but normally they carried 267 rounds per gun. Early aircraft had small doors covering each gun port. They opened in 0.05 seconds but were difficult to keep properly adjusted, so they were soon deleted.

The airplane could also be armed with two bombs and up to sixteen 5-inch (12.7 centimeter) High Velocity Aerial Rockets (HVAR) on underwing hardpoints.

North American Aviation built thirty-three P-86A-1-NAs. The U.S. Air Force ordered 190 F-86Bs, but these were cancelled in favor of the F-86A-5-NA.

The F-86A became operational with the 1st Fighter Group at March Air Force Base, near Riverside, California. In February 1949, a contest was held within the group to select a name for the new fighter. “Sabre” was chosen.

47-605 was the first production P-86A-1-NA Sabre. (U.S. Air Force)

© 2019, Bryan R. Swopes

20 May 1941

Aviation, , , , , , , , , , , , ,
NAA test pilot Robert C. Chilton stand on the wing of P-51B-10-NA 42-106435. (North American Aviation, Inc.)
North American Aviation test pilot Robert C. Chilton standing on the wing of P-51B-10-NA Mustang 42-106435. (North American Aviation, Inc.)

20 May 1941: North American Aviation, Inc., test pilot Robert Creed Chilton took the first XP-51 for its maiden flight at Mines Field, Los Angeles, California. The XP-51 was the fourth production Mustang Mk.I built for the Royal Air Force, (North American serial number 73-3101) and assigned registration number AG348.

The Mustang was reassigned to the U.S. Army Air Force, designated as XP-51, serial number 41-038, and sent to Wright Field, Dayton, Ohio, for evaluation.

North American Aviation Mustang Mk.I AG348 at Mines Field, California, 1941. North American Aviation, Inc., photograph 73-0-9. (Ray Wagner Collection/SDASM)
North American Aviation Mustang Mk.I AG348, Mines Field, California, 1941. North American Aviation, Inc., photograph 73-0-10. (Ray Wagner Collection/SDASM)
North American Aviation Mustang Mk.I AG348 at Mines Field, California, 1941. North American Aviation, Inc., photograph. (Ray Wagner Collection/SDASM)

Later, the XP-51 was extensively tested by the National Advisory Committee for Aeronautics (N.A.C.A.) at the Langley Memorial Aeronautical Laboratory, Langley Field, Hampton, Virginia.

Today, the restored XP-51 is in the collection of the E.A.A. AirVenture Museum at Oshkosh, Wisconsin.

North American Aviation XP-51 41-038 at the NACA Langley Memorial Aeronautical Laboratory. (NASA LMAL 27030)
North American Aviation XP-51 41-038 at the NACA Langley Memorial Aeronautical Laboratory. (NASA)

The Mustang Mk.I (NAA Model NA-73) was a single-place, single engine fighter primarily of metal construction with fabric control surfaces. It was 32 feet, 3 inches (9.830 meters) long with a wingspan of 37 feet, 5/16-inches (11.373 meters) and height of 12 feet, 2½ inches (3.721 meters). The airplane’s empty weight was 6,280 pounds (2,849 kilograms) and loaded weight was 8,400 pounds (3,810 kilograms).

North American Aviation XP-51 41-039 at NACA Langley. (NASA)
North American Aviation XP-51 41-039 at NACA Langley. Note the increased length of the carburetor intake. (NASA)

The Mustang was powered by a liquid-cooled, supercharged, 1,710.597-cubic-inch-displacement (28.032 liter) Allison Engineering Company V-1710-F3R (V-1710-39) single overhead cam (SOHC) 60° V-12 engine with a compression ratio of 6.65:1. The -F3R had a Normal Power rating of 880 horsepower at 2,600 r.p.m., at Sea Level, and 1,000 horsepower at 2,600 r.p.m. at 11,000 feet (3,353 meters). It had a Takeoff and Military Power rating of 1,150 horsepower at 3,000 r.p.m., to 11,800 feet (3,597 meters). The engine turned a 10 foot, 9 inch (3.277 meter) diameter three-bladed Curtiss Electric constant-speed propeller through a 2.00:1 gear reduction. The V-1710-F3R was 7 feet, 4.38 inches (2.245 meters) long, 3 feet, 0.54 inches (0.928 meters) high, and 2 feet, 5.29 (0.744 meters) wide. It weighed 1,310 pounds (594 kilograms).

The Mustang Mk.I had a maximum speed of 382 miles per hour (615 kilometers per hour) at 13,700 feet (4,176 meters), the Allison’s critical altitude, and cruise speed of 300 miles per hour (483 kilometers per hour). The service ceiling was 30,800 feet (9,388 meters) and range was 750 miles (1,207 kilometers).

North American Aviation XP-51 41-038 at NACA Langley Memorial Aeronautical Laboratory, right profile. (NASA LAML)
North American Aviation XP-51 41-038 at NACA Langley Memorial Aeronautical Laboratory, right profile. (NASA)

The Mustang Mk.I was armed with four air-cooled Browning .303 Mk.II aircraft machine guns, two in each wing, and four Browning AN-M2 .50-caliber machine guns, with one in each wing and two mounted in the nose under the engine.

North American Aviation XP-51 41-038 at NACA Langley Memorial Aeronautical Laboroatory. (NASA LAML 27045)
North American Aviation XP-51 41-038 at NACA Langley Memorial Aeronautical Laboratory, right three-quarter view. (NASA)

The Mk.I was 30 m.p.h. faster than its contemporary, the Curtiss P-40 Warhawk, though both used the same engine. Below 15,000 feet, the Mustang was also 30–35 m.p.h faster than a Supermarine Spitfire, which had a more powerful Roll-Royce Merlin V-12.

The XP-51 would be developed into the legendary P-51 Mustang. In production from 1941 to 1945, a total of 16,766 Mustangs of all variants were built.

North American Aviation XP-51 41-038 at NACA Langley Memorial Aeronautical Laboratory, rear view. (NASA LMAL 27033)
North American Aviation XP-51 41-038 at NACA Langley Memorial Aeronautical Laboratory, rear view. (NASA)

Robert Creed Chilton was born 6 February 1912 at Eugene, Oregon, the third of five children of Leo Wesley Chilton, a physician, and Edith Gertrude Gray. He attended Boise High School in Idaho, graduating in 1931. Chilton participated in football, track and basketball, and also competed in the state music contest. After high school, Chilton attended the University of Oregon where he was a member of the Sigma Chi fraternity (ΣΧ). He was also a member of the Reserve Officers Training Corps (ROTC).

Bob Chilton enlisted as an Aviation Cadet in the U.S. Army Air Corps, 25 June 1937. He was trained as a fighter pilot at Randolph Field and Kelly Field in Texas, and was commissioned as a Second Lieutenant in 1938. Lieutenant Chilton was assigned to fly the Curtiss P-36 Hawk with the 79th Pursuit Squadron, 20th Pursuit Group, at Barksdale Field, Louisiana. Because of a medical condition, he was released from active duty, 1 April 1939.

At some time prior to 1940, Bob Chilton, married his first wife, Catherine. They lived in Santa Maria, California, where he worked as a pilot at the local airport.

In January 1941, Chilton went to work as a production test pilot for North American Aviation, Inc., Inglewood, California. After just a few months, he was assigned to the NA-73X.

Chilton married his second wife, Betty W. Shoemaker, 15 November 1951.

On 10 April 1952, Bob Chilton returned to active duty with the U.S. Air Force, with the rank of lieutenant colonel. He served as Chief of the Republic F-84 and F-105 Weapons System Project Office, Air Material Command, at Wright-Patterson Air Force Base, Dayton, Ohio, until 9 March 1957.

From 1958, Chilton was a vice president for Horkey-Moore Associates, an engineering research and development company in Torrance, California, founded by former North American aerodynamacist Edward J. Horkey. In 1961, he followed Horkey to the Space Equipment Corporation, parent company of Thompson Industries and Kerr Products, also located in Torrance. Chilton served as corporate secretary and contracts administrator.

Chilton married his third wife, Wilhelmina E. Redding (Billie E. Johnson) at Los Angeles, 26 July 1964. They divorced in 1972.

In 1965, Bob Chilton returned to North American Aviation as a flight test program manager. He retired in 1977.

Robert Creed Chilton died at Eugene, Oregon, 31 December 1994, at the age of 82 years.

North American Aviation XP-51 at Wright Field. (Charles M. Daniels Collection, San Diego Air & Space Museum Archives, Catalog #: 15_002838)

© 2018, Bryan R. Swopes

20 May 1937

Aviation, , , , , , , , , ,
Amelia Earhart with her Lockheed Electra 10E, NR16020.

Leg 1: After her Lockheed Electra 10E Special, NR16020, was repaired by Lockheed following a takeoff accident at Wheeler Field, Oahu, in March, Amelia Earhart repositioned it to Oakland Municipal Airport to begin her second attempt to fly around the world. Because of changing weather patterns since the earlier attempt, this time her route will be eastward.

Great Circle route between Oakland Airport and Union Air Terminal. (Great Circle Mapper)

On 20 May 1937, without any public notice, Earhart and her navigator, Captain Frederick J. Noonan, left Oakland, California, on the first leg of the trip: 283 nautical miles (325 miles (523 kilometers) to Union Air Terminal, Burbank, California (now, Hollywood Burbank Airport—BUR), where the airplane was manufactured and repaired. They arrived at about 6:00 p.m. and remained there over night.

“The rebuilt Electra came out of the Lockheed plant on May 19. Two days later we flew it to Oakland. . .  As that time we had made no announcement of my decision to reverse the direction of the flight. It seemed sensible to slip away as quietly as we could. While I was actually heading for Miami, with hope of keeping on from there eastward, technically the journey from Burbank across the country was a shake-down flight. If difficulties developed we would bring the ship back to the Lockheed plant for further adjustments.”

—Amelia Earhart

Amelia Earhart in the cockpit of her Electra. (Rudy Arnold Collection)

© 2018, Bryan R. Swopes

20–21 May 1932

Aviation, , , , , , , , , , , ,
Amelia Earhart at Harbor Grace, Newfoundland, 20 May 1932. Photographer: Ernest Maunder. Courtesy of Library and Archives Canada (PA-057854).
Amelia Earhart at Harbor Grace, Newfoundland, 20 May 1932. Photographer: Ernest Maunder. Courtesy of Library and Archives Canada (PA-057854).

20 May 1932: At 7:12 p.m., local, aviatrix Amelia Earhart departed Harbor Grace, Newfoundland, on a solo transoceanic flight. Her airplane was a modified single-engine Lockheed Model 5B Vega, registration NR7952.

Her plan was to fly all the way to Paris, but after her altimeter had failed, encountering adverse weather, including heavy icing and fog, a fuel leak, and a damaged exhaust manifold, Earhart landed in a field at Culmore, Northern Ireland. The distance flown was 2,026 miles (3,260.5 kilometers). Her elapsed time was 14 hours, 56 minutes.

A lone, astonished farmer saw her land.

Amelia cut the switches, climbed out of the plane, and, as the man approached the plane, called out, “Where am I?”

Danny McCallion replied obligingly and with excruciating accuracy. “In Gallegher’s pasture.”

—The Sound of Wings by Mary S. Lovell, St. Martin’s Press, New York, 1989, Chapter Fifteen at Page 183.

Amelia Earhart with her Lockheed Vega 5B, NR7952, at Culmore, North Ireland after her solo transatlantic flight, 21 May 1932. (National Library of Ireland)

Though she didn’t make it all the way to Paris, she was the first woman—and only the second person, after Charles A. Lindbergh—to fly solo across the Atlantic Ocean. Lindbergh’s flight was on the same date, five years earlier.

Great Circle route between Harbour Grace Airport, Newfoundland, and Londonderry Airport, near Culmore, Northern Ireland. 1,754 nautical miles (2,019 statute miles/3,249 kilometers). (Great Circle Mapper)

In an unusual move, Amelia Earhart, a civilian, was awarded the United States military’s Distinguished Flying Cross by Patrick J. Hurley, Secretary of War, 18 July 1932.

Amelia Earhart’s Distinguished Flying Cross certificate signed by Patrick J. Hurley, Secretary of War.

Built by the Lockheed Aircraft Company in December 1928, the Vega is a single-engine high-wing monoplane designed to carry a pilot and up to seven passengers. The fuselage was molded laminated plywood monocoque construction and the wing was cantilevered wood. The Vega 5B is 27 feet, 6 inches (8.382 meters) long with a wingspan of 41 feet (12.497 meters) and overall height of 8 feet, 2 inches (2.489 meters).

Amelia Earhart stands in front of her Lockheed Model 5B Vega, NR7952, at Union Airport, 1932. Left to right, Earhart; Lockheed founder Allan Loughead; Paul Mantz; and Lockheed president Lloyd Stearman. (Philip S. Dockter/Valley Relics Museum)

Earhart’s Vega, serial number 22, was certified by the Department of Commerce, 17 September 1931, with its empty weight increased 220 pounds (99.8 kilograms) to 2,695 pounds (1,222.4 kilograms) and maximum gross weight of 4,375 pounds (1984.5 kilograms).

Aircraft Registration Certificate, Lockheed Vega, serial number 22, NC7952, 1928.

NR7952 was modified at the Fokker Aircraft Corporation of America factory in Teterboro, New Jersey, to increase the fuel capacity to 420 gallons (1,589.9 liters). While it was there, Earhart’s mechanic, Eddie Gorski, replaced the original Pratt & Whitney Wasp B engine with a new Wasp C, an air-cooled, supercharged 1,343.804-cubic-inch-displacement (22.021 liter) nine cylinder radial engine with a compression ration of 5.25:1. The Wasp C was rated at 420 horsepower at 2,000 r.p.m. at Sea Level, burning 58 octane gasoline.¹ It was a direct-drive engine, and turned a two-bladed Hamilton Standard controllable-pitch propeller. The Wasp C was 3 feet, 6.63 inches (1.083 meters) long, 4 feet, 3.44 inches (1.307 meters) in diameter and weighed 745 pounds (338 kilograms).

The standard Vega 5 had a cruising speed of 165 miles per hour (265.5 kilometers per hour) and maximum speed of 185 miles per hour (297.7 kilometers per hour). The service ceiling was 15,000 feet (4,572 meters). Range with standard fuel tanks was 725 miles (1,166.8 kilometers).

Amelia Earhart disappeared in 1937 while attempting to fly around the world. Her Lockheed Model 5B Vega, NR7952, is in the collection of the Smithsonian Institution National Air and Space Museum.

Amelia Earhart's Lockheed Vega 5b, NR7952, at the Smithsonian Institution National Air and Space Museum.
Amelia Earhart’s Lockheed Model 5B Vega, NR7952, at the Smithsonian Institution National Air and Space Museum. (NASM)

¹ The Pratt & Whitney Wasp C was also used by the U.S. Army and Navy, designated R-1340-7. It was rated at 450 horsepower at 2,100 r.p.m. at Sea Level.

© 2019, Bryan R. Swopes