26 April 1948: At Muroc Field (now known as Edwards Air Force Base), in the high desert of southern California, North American Aviation test pilot George Welch put the prototype XP-86 Sabre, 45-59597, into a 40° dive and broke the Sound Barrier. It is only the second U.S. aircraft to fly supersonic. The first was the Bell X-1, piloted by Chuck Yeager, only a few months earlier.
Or, maybe not.
In his book, Aces Wild: The Race For Mach 1, fellow North American Aviation test pilot Albert W. Blackburn makes the case that George Welch had taken the prototype XP-86 Sabre supersonic on its first flight, 1 October 1947, and that he had done so three times before Chuck Yeager first broke the Sound Barrier with the Bell X-1 rocketplane, 14 October 1947. Blackburn described two runs through the NACA radar theodolite with speeds of Mach 1.02 and 1.04 on 13 November 1947.
Mr. Blackburn speculates—convincingly, in my opinion—that Secretary of the Air Force W. Stuart Symington, Jr., ordered that Welch’s excursions beyond Mach 1 were to remain secret. However, during a radio interview, British test pilot Wing Commander Roland Prosper (“Bee”) Beamont, C.B.E, D.S.O. and Bar, D.F.C. and Bar, stated that he had flown through the Sound Barrier in the number two XP-86 Sabre prototype (45-59598). Once that news became public, the U.S. Air Force released a statement that George Welch had flown beyond Mach 1 earlier, but gave the date as 26 April 1948.
It wasn’t long after the first flight of the XP-86 on October 1, 1947, that Welch dropped into Horkey’s[Edward J. Horkey, an aerodynamicist at North American Aviation]office at the Inglewood plant. He wanted to talk about his recent flight and some “funny” readings in the airspeed indicator. He had made a straight-out climb to more than 35,000 feet. Then, turning back toward Muroc Dry Lake, he began a full-power, fairly steep descent.
“I started at about 290 knots,” Welch was explaining to Horkey. “In no time I’m at 350. I’m still going down, and I’m still accelerating but the airspeed indicator seems stuck like there’s some kind of obstruction in the pitot tube. I push over a little steeper and by this time I’m through 30,000 feet. All of a sudden, the airspeed indicator flips to 410 knots. The aircraft feels fine, no funny noises, no vibration. Wanted to roll off to the left, but no big deal. Still, I leveled out at about 25,000 and came back on the power. The airspeed flicked back to 390. What do you think?”
“. . . You may be running into some Mach effects. . . .”
— Aces Wild: The Race For Mach 1, by Al Blackburn, Scholarly Resources Inc., Wilmington, Delaware, 1999, at Pages 147–148.
The “funny” reading of the airspeed indicator became known as the “Mach jump.” George Welch was the first to describe it.
The Sabre became a legendary jet fighter during the Korean War. 9,860 were built by North American, as well as by licensees in Canada, Australia and Japan.
George Welch had been recommended for the Medal of Honor for his actions as a P-40 Warhawk fighter pilot in Hawaii, December 7, 1941. He was killed while testing a North American Aviation F-100A Super Sabre, 12 October 1954.
3 April 1926: Virgil Ivan Grissom was born at Mitchell, Indiana, the second of five children of Dennis David Grissom, an electrician, and Cecile King Grissom. “Gus” Grissom attended Mitchell High School, graduating in 1944. He was a member of the Hi-Y Club, the Camera Club, and the Signal Club.
Upon graduation from high school. Virgil I. Grissom enlisted as an aviation cadet in the Air Corps, United States Army, at Fort Benjamin Harrison, Lawrence, Indiana, 9 August 1944. He was assigned to basic flight training at Sheppard Field, Texas, but the War came to an end before he could graduate as a pilot. Then reassigned as a clerk, he requested to be discharged from the Air Corps, which he was in November 1945.
Grissom married Miss Betty Lavonne Moore at Mitchell, Indiana, 6 July 1945. They wood have two sons, Scott and Mark. (In Korea, Grissom named his F-86 Scotty after his first son.)
After the war, Grissom enrolled at Purdue University, Lafayette, Indiana, and in 1950, graduated with the degree of Bachelor of Science in Mechanical Engineering.
He then re-joined the U.S. Air Force in 1950 and was trained at Randolph Air Force Base, Texas, and Williams Air Base, Arizona, where he specialized as a fighter pilot. He was commissioned as a second lieutenant, U.S. Air Force, in March 1952.
Lieutenant Grissom was assigned to he 334th Fighter Interceptor Squadron, 4th Fighter Interceptor Wing, based at Kenpo Air Base (K-14), in the Republic of South Korea. He flew 100 combat missions in the North American Aviation F-86 Sabre. Grissom was promoted to first lieutenant, 11 March 1952. he requested to fly another 25 combat missions, but that was declined and he returned to the United States. Lieutenant Grissom was then assigned as a flight instructor at Bryan Air Force Base, Texas.
Grissom attended a one year program at the Air Force Institute of Technology at Wright-Patterson Air Force Base, Dayton, Ohio, and earned a second bachelor’s degree in aircraft engineering. He was then sent to the Air Force Test Pilot School at Edwards Air Force Base, California (Class 56D). After completion, he was assigned as a fighter test pilot back at Wright-Patterson.
One of 508 pilots who were considered by NASA for Project Mercury, Gus Grissom was in the group of 110 that were asked to attend secret meetings for further evaluation. From that group, 32 went on with the selection process and finally 18 were recommended for the program. Grissom was one of the seven selected.
Major Grissom was the second American to “ride the rocket” aboard Mercury-Redstone 4. He named his space capsule Liberty Bell 7. The spacecraft reached a maximum altitude of 102.8 nautical miles (118.3 statute miles, 190.4 kilometers) and traveled 262.5 nautical miles (302.1 statute miles, 486.2 kilometers) down range. During the 15 minute, 37 second, flight, Grissom was weightless for 5:00 minutes.
Next he orbited Earth as commander of Gemini III along with fellow astronaut John Young. He was back-up commander for Gemini VI-A, then went on to the Apollo Program.
Gus Grissom was selected as the commander for Apollo I in January 1968. This was to be the first manned flight of the Apollo spacecraft. Ed White and Roger Chaffee were the other members of the flight crew.
As commander of AS-204 (Apollo I), LCOL Virgil I. Grissom, USAF was killed along with Ed White and Roger Chafee during a test on the launchpad, 27 January 1967.
Gus Grissom was an Air Force Command Astronaut with over 4,600 hours flight time. He was the first American astronaut to fly into space twice, and logged 5 hours, 7 minutes of space flight. For his military service, Grissom was awarded the Distinguished Flying Cross; the Air Medal with one bronze oak leaf cluster (two awards); the American Campaign medal; the World War II Victory Medal; teh Korean Service Medal; the United Nations Korea medal, and the Korean War Service Medal of the Republic of South Korea. For his NASA service, he was awarded the Congressional Space Medal of Honor (posthumous); the NASA Distinguished Service Medal (two awards); and the NASA Exceptional Service Medal.
Had he lived, it is very possible that Grissom would have commanded the first Apollo mission to land on The Moon.
The remains of Lieutenant Colonel Virgil Ivan Grissom, United States Air Force, NASA Astronaut, are buried at the Arlington National Cemetery, Arlington, Virginia.
13 December 1951: Major George Andrew Davis, Jr., United States Air Force, commanding officer of the 334th Fighter Interceptor Squadron, 4th Fighter Interceptor Wing, flying a North American F-86E-10-NA Sabre, serial number 51-2752, led his unit on two “MiG Sweeps.”
During the mid-day fighter sweep, the 334th encountered Mikoyan Gurevich MiG 15 fighters of the 18th GIAP, 303rd IAD, Voyenno-Vozdushnye Sily (the Soviet Air Force), and an air battle ensued. Major Davis was credited with shooting down two of the Russian fighters. The pilot of one of the MiGs, I.A. Gorsky, was killed. The identity and fate of the second Soviet pilot is not known.
During a second sweep in mid-afternoon, George Davis and the 334th again encountered enemy MiG 15s of the 40th Regiment, 14th Division, of the Peoples Liberation Army Air Force (Chinese Air Force). At 3:52 p.m. (1352) Davis shot down one of the Chinese MiG 15s. One minute later, he shot down another, his fourth aerial victory for the day.
These frames of film from the gun camera of Davis’ F-86 Sabre show a MiG 15 trailing smoke after being hit by the Sabre’s six .50-caliber machine guns. Chinese sources confirmed the loss of two MiG 15s, but again, the identities of the pilots and whether or not they survived is not known.
30 November 1951: Major George Andrew Davis, Jr., commanding the 334th Fighter Interceptor Squadron, 4th Fighter Interceptor Wing, based at Kimpo Air Base, South Korea, led a patrol of eight North American Aviation F-86 Sabre fighters near the Yalu River, dividing Korea from China. This area was known as “MiG Alley” because of the large numbers of Russian-built Mikoyan-Gurevich MiG-15 fighters which were based on the Chinese side of the river.
At about 4:00 p.m., the American pilots saw a group of nine Russian Tupolev Tu-2 twin-engine medium bombers, escorted by 16 Lavochkin La-11 fighters. The bombers were on a mission to attack Taewa-do Island.
Davis led his fighters in an attack, making four firing passes on the bombers. He shot down three of the Tu-2s, when one of his pilots, Captain Raymond O. Barton, Jr., called for help. Barton’s Sabre, F-86A-5-NA 49-292, was under attack by 24 MiG-15s which had arrived to reinforce the bombing mission. Barton later described the battle:
“. . . I broke left again and was going to make another pass when I checked my ‘six o’clock’ to clear for my wingman. All of the sudden the SOB started shooting at me, and only then did I realize that I had attracted far more than one MiG. I turned into them. . . I called for help, and the only response I got was from my roommate, Major George Davis. I’ll never forget his reply. ‘I don’t have enough fuel left either but I’m on the way.’ All the MiGs except one had left the area. I had a huge hole where my left fuel cap had been, but I was still flying. When George reached me, he asked me to make a couple of identifying turn reversals. I reluctantly did and he shot that SOB right off my butt.“
—F-86 Sabre Aces of the 4th Fighter Wing, by Warren Thompson, Osprey Publishing Ltd., Oxford, 2006, Chapter 2 at Page 32.
Major Davis escorted Captain Barton back to their base, landing with just five gallons of fuel remaining in his tanks.
For his actions, Major George A. Davis, Jr., was awarded the Distinguished Service Cross. Having shot down four enemy aircraft during one fighter patrol, Davis’ score of aerial victories during his short time in Korea rose to six, making him an ace for the Korean War. Davis had previously shot down seven enemy airplanes during World War II with his Republic P-47 Thunderbolt. Davis was the first American pilot to become an ace in two wars.
George Davis would soon be credited with another eight victories, making him the leading American ace up to that time. He was killed in action 10 February 1952 in an air battle for which he would be awarded the Medal of Honor.
Raymond Oscar (“R.O.”) Barton, Jr., was born at Omaha, Nebraska, 8 March 1927. he was the son of Major General Raymond O. Barton and Clare Fitzpatrick Barton. He was a 1948 graduate of the United States Military Academy at West Point, New York. Barton flew 100 combat missions during the Korean War. He is credited with three MiG 15s destroyed and another 7 damaged. R.O. Barton died at Augusta, Georgia, in 2003.
1 October 1947: After three years development in which 801,386 engineering hours and 340,594 drafting hours had been expended, the first prototype North American Aviation XP-86 (company designation NA-140), serial number 45-59597, was ready for its first flight at Muroc Dry Lake in the high desert, north of Los Angeles, California.
Completed at North American’s Inglewood plant on 8 August 1947, it was trucked to Muroc in mid-September. It was reassembled, everything was checked out, and after a few taxi tests, company test pilot George S. Welch took off for a initial familiarization flight. Chief Test Pilot Bob Chilton flew chase in an XP-82 Twin Mustang with a company photographer on board. The duration of the first flight was 1 hour, 18 minutes.
During this first flight, George Welch climbed to 35,000 feet (10,668 meters):
“In a little more than ten minutes he had reached 35,000 feet. Leveling out, the test pilot smiled as he watched the indicated airspeed accelerate to 320 knots. He estimated that should be 0.90 Mach number. . . Rolling into a 40 degree dive, he turned west. . . The airspeed indicator seemed to be stuck at about 350 knots. The Sabre was behaving just fine. Then at 29,000 feet, there was a little wing roll. Correcting the roll, George pushed into a steeper dive. The airspeed indicator suddenly jumped to 410 knots and continued to rise. At 25,000 feet, he pulled the Sabre into level flight and reduced power. The wing rocked again and the airspeed jumped back to 390.”
—Aces Wild: The Race for Mach 1, by Al Blackburn, Scholarly Resources Inc., Wilmington, Delaware, 1998, at Chapter 5, Pages 144–145.
George Welch was the first to report instrument readings that would be referred to as “Mach jump.” It has been argued that George Welch flew the XP-86 beyond Mach 1 during this flight, breaking the “sound barrier” two weeks before Chuck Yeager did with the Bell X-1 rocketplane. During flight testing, it was firmly established that the XP-86 could reach Mach 1.02–1.04 in a dive, so it is certainly possible that he did so on the Sabre’s first flight.
The XP-86 was unlike any airplane before it. It was the first airplane with a swept wing. After analyzing test data from the Messerschmitt Me 262, North American’s engineers designed a wing with a 35° degree sweepback to its leading edge. 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 wing sweep allowed high speed shock waves to form without stalling the entire wing.
The wing also 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.
The XP-86 prototypes were 37 feet, 6½ inches (11.443 meters) long with a wingspan of 37 feet, 1–7/16 inches (11.314 meters) and overall height of 14 feet, 9 inches (4.496 meters). The empty weight was 9,730 pounds (4,413.5 kilograms), gross weight, 13,395 pounds (6,075.9 kilograms) and maximum takeoff weight was 16,438 pounds (7,456.2 kilograms).
The XP-86 was initially powered by a General Electric-designed, Chevrolet-built J35-C-3 turbojet which produced 4,000 pounds of thrust. This was soon changed to an Allison J35-A-5. Performance testing was conducted with the Allison engine installed. The J35 was a single-spool, axial-flow turbojet engine with an 11-stage compressor and single-stage turbine. The J35-A-5 was rated at 4,000 pounds of thrust (17.79 kilonewtons) at 7,700 r.p.m. (static thrust, Sea Level). The engine was 14 feet, 0.0 inches (4.267 meters) long, 3 feet, 4.0 inches (1.016 meters) in diameter and weighed 2,400 pounds (1,089 kilograms).
The maximum speed of the XP-86 at Sea Level was 0.787 Mach (599 miles per hour, 964 kilometers per hour), 0.854 Mach (618 miles per hour, 995 kilometers per hour) at 14,000 feet (4,267 meters) and 575 miles per hour (925 kilometers per hour) at 35,000 feet (10,668 meters)—0.875 Mach.
The prototype fighter was able to take off at 125 miles per hour (201 kilometers per hour) in just 3,020 feet (920.5 meters) of runway. It could climb to 30,000 feet (9,144 meters) in 12.1 minutes and had a service ceiling of 41,300 feet (12,588 meters).
XP-86 45-59597 was expended as a target during nuclear weapons tests. On 25 May 1953, it was 1,850 feet from ground zero of Upshot Knothole Grable. The only part still intact was the engine, which was thrown 500 feet.
George Welch was born George Lewis Schwartz, in Wilmington, Delaware, 10 May 1918. His parents changed his surname to Welch, his mother’s maiden name, so that he would not be effected by the anti-German prejudice that was widespread in America following World War I. He studied mechanical engineering at Purdue, and enlisted in the Army Air Corps in 1939.
George S. Welch is best remembered as one of the heroes of Pearl Harbor. He was one of only two fighter pilots to get airborne during the Japanese surprise attack on Hawaii, 7 December 1941. Flying a Curtiss P-40B Warhawk, he shot down three Aichi D3A “Val” dive bombers and one Mitsubishi A6M2 Zero fighter. For this action, Lieutenant General H.H. “Hap” Arnold recommended the Medal of Honor, but because Lieutenant Welch had taken off without orders, an officer in his chain of command refused to endorse the nomination. He received the Distinguished Service Cross.
During World War II, George Welch flew the Bell P-39 Airacobra and Lockheed P-38 Lightning on 348 combat missions. He had 16 confirmed aerial victories over Japanese airplanes and rose to the rank of Major.
Suffering from malaria, George Welch was out of combat, and when North American Aviation approached him to test the new P-51H Mustang, General Arnold authorized his resignation. Welch test flew the P-51, FJ-1 Fury, F-86 Sabre and F-100 Super Sabre. He was killed 12 October 1954 when his F-100A Super Sabre came apart in a 7 G pull up from a Mach 1.5 dive.
After testing, the North American Aviation XP-86 was approved for production as the F-86A. It became operational in 1949. The first squadron to fly the F-86 held a naming contest and from 78 suggestions, the name “Sabre” was chosen. The F-86 Sabre was in production until 1955 at North American’s Inglewood, California, and Cleveland, Ohio, plants. It was also built under license by Canadair, Ltd., Sain-Laurent, Quebec, Canada; the Commonwealth Aircraft Corporation, Port Melbourne, Victoria, Australia; and Mitsubishi Heavy Industries at Nagoya, Aichi Prefecture, Japan. A total of 9,860 Sabres were built. They served with the United States Air Force until 1970.
XP-86 45-59597 was expended in nuclear weapons tests, Operation Snapper Easy and Snapper Fox, at the Nevada Test Site, Frenchman’s Flat, Nevada, in May 1952. The second and third prototypes, 45-59598 and 45-59599, met similar fates.