20 November 1963: The U.S. Air Force Tactical Air Command accepted its first two production McDonnell F-4C Phantom II jet fighters, F-4C-15-MC 63-7415 ¹ and F-4C-15-MC 63-7416. These aircraft were the ninth and tenth production F-4Cs. They were flown from the McDonnell plant at St. Louis, Missouri, to MacDill Air Force Base, Tampa, Florida, by Brigadier General Gilbert Louis Meyers, commanding the 836th Air Division, and Colonel Frank Kendall (“Pete”) Everest, a world-famous test pilot, commanding the 4453rd Combat Crew Training Squadron. Co-pilot for General Meyers was Captain Joseph D. Moore. Captain Thomas C. Ross flew with Colonel Everest. The two new fighters arrived at 11:00 a.m., local time.
Lieutenant General Charles B. Westover, Vice Commander, Tactical Air Command, formally accepted the new fighters on behalf of TAC. Up until this time, the 4453rd had been training crews with McDonnell F-4B Phantom IIs on loan from the United States Navy.
The McDonnell F-4C Phantom II (originally designated F-110A Spectre) was produced for the U.S. Air Force, based on the U.S. Navy McDonnell F4H-1 (F-4B after 1962) fleet defense interceptor. Evaluation testing had shown the the Navy’s F4H was superior to the Air Force Convair F-106 Delta Dart. It was faster, could fly higher, had a longer range and greater payload. It was also better suited as a tactical fighter.
The Navy operated its Phantom IIs with a pilot and a radar systems operator. The Air Force’s F-4C variant was equipped with dual flight controls and was flown by two rated pilots. The F-4C was externally the same as the F-4B, but otherwise differed by the addition of a ground attack capability. Also, while the F-4B used a hose-and-drogue system for air-to-air refueling, the F-4C was equipped with a boom refueling system. It retained the folding wings and arresting hook of the Navy variant, but deleted catapult provisions.
The F-4C was 58 feet, 3¾ inches (17.774 meters) long, with a wingspan of 38 feet, 5 inches (11.709 meters) and height of 16 feet, 3 inches (4.953 meters). Its empty weight was 28,496 pounds (12,926 kilograms) and its maximum takeoff weight was 58,000 pounds (26,308 kilograms).
The F-4C-15-MC was powered by two General Electric J79-GE-15 engines. The J79 is a single-spool, axial-flow turbojet engine, with a 17-stage compressor section and 3-stage turbine. The J79-GE-15 is rated at 10,900 pounds of thrust (48.49 kilonewtons) and 17,000 pounds (75.62 kilonewtons) with afterburner. It is 17 feet, 4.7 inches (5.301 meters) long, 3 feet, 2.3 inches (0.973 meters) in diameter and weighs 3,699 pounds (1,677.8 kilograms).
The F-4C had a maximum speed of 826 miles per hour (1,329 kilometers per hour)—Mach 1.09—at Sea Level, and 1,433 miles per hour (2,306 kilometers per hour)—Mach 2.17— at 48,000 feet (14,630 meters). The fighter’s service ceiling was 56,100 feet (17,099 meters). Its maximum unrefueled range, with external fuel tanks, was 1,926 miles (3,100 kilometers).
The standard armament for the F-4C were four AIM-7 Sparrow radar-homing missiles carried in recessed in the bottom of the fuselage. Four AIM-9 Sidewinder heat-seeking missiles could be carried on underwing pylons. A maximum of 16,000 pounds (7,257 kilograms) of bombs on five hardpoints.
During the Vietnam War, the missile armament of the Phantom II was found unsatisfactory in dogfights with enemy aircraft. The violent maneuvers of Air Combat Maneuvering (“ACM”) made it difficult for the missiles to align and track the intended target. Of 612 AIM-7 Sparrows fired by F-4s, only 56 enemy aircraft were destroyed, while 187 AIM-9 Sidewinders brought down 29 enemy aircraft. This was a kill ratio of 9% and 16%, respectively.
Forward-thinking planners had assumed that an all-missile armament was all that was required in the modern era, so F-4s were built without any machine guns or cannon. The Air Force used an SUU-16/A pod containing a General Electric M61A1 20 mm rotary cannon with 1,200 rounds of ammunition mounted to the F-4’s centerline hardpoint. (Two additional SUU-16/A pods could be mounted on the outboard underwing hardpoints.) This was useful in close-in combat, but the airplane was not equipped with a suitable gun sight. It was not until the F-4E variant that a gun was incorporated into the airplane.
The F-4C first flew 27 May 1963. 583 of this variant before production shifted to the F-4D in 1966. The F-4C remained in service until the last was retired from the Oregon Air National Guard in 1989.
Recommended reading: Engineering the F-4 Phantom II: Parts Into Systems by Glenn E. Bugos, Naval Institute Press, Annapolis, Maryland, 1996
¹ Source: UNITED STATES AIR FORCE STATISTICAL DIGEST FISCAL YEAR 1964 (19th Edition), Directorate of Data Automation (AFADA), Comptroller of the Air Force, Headquarters, USAF, Washington, D.C.: Chronology of United States Air Force Major Events— FY 1964, at Page XXXVIII
20 November 1940: North American Aviation’s Chief Test Pilot, Paul Baird Balfour, made his first flight in the NA-73X, NX19998, prototype for a Royal Air Force fighter, the Mustang Mk.I.
Vance Breese was the free-lance test pilot who made the first seven flights in the new airplane. Breese claimed to have made a bet with North American executives that Balfour would crash the prototype on his first flight.
This flight was scheduled to be a high speed test. Edgar Schmued, the designer, offered to show Balfour around the airplane. “Before this flight, I asked Balfour to get into the airplane and go through the routine of a takeoff and flight. He responded that one airplane is like another and he would not need the routine checkout.”
The ground crew started the NA-73X’s 1,150 horsepower Allison V-1710-39 liquid-cooled V-12 engine at 5:40 a.m. and let it warm up to normal operating temperature. When it was restarted just prior to Paul Balfour’s flight, “it was a little hard to start,” according to Olaf Anderson, the airplane’s mechanic.
Balfour took off from Mines Field at about 7:10 a.m. After about twelve minutes of flight, the Allison stopped running. Balfour was too far from Mines Field to make it back to the runway. He landed in a plowed field west of Lincoln Boulevard. When the tires hit the soft surface, the prototype flipped over. Balfour was not hurt and was able to crawl out of the upside-down wreck.
The Civil Aeronautics Board report described the damage as “engine housing broken, both wingtips damaged, tail surfaces damaged, top of fuselage damaged, and other miscellaneous damage.” The NA-73X had accumulated just 3 hours, 20 minutes of flight.
Vance Breese won his bet.
According to the C.A.B. investigation, the engine had stopped due to fuel starvation when Balfour neglected to select another tank.
The prototype was taken back to the factory and rebuilt. It would become the famous Mustang, one of the most significant aircraft of World War II.
Robert C. Chilton was hired as the new Chief Test Pilot. He would continue testing the Mustang developments throughout the war. Chilton made his first flight in NA-73X on 3 April 1941.
Paul Balfour continued to work for North American Aviation, testing the NA-40 and NA-40B prototypes and the B-25 Mitchell medium bomber. He later served in the United States Air Force.
Paul Baird Balfour was born 5 July 1908 in Washington State. He was the son of Fred Patrick Balfour and Edna May Baird Balfour. Balfour attended two years of college.
Paul Balfour entered the U.S. Army Air Corps (prior to 1930). He was stationed at Rockwell Field, San Diego, California.
Balfour married Martha Lillette Cushman of Coronado, California, at Yuma, Arizona, 6 June 1930.
Balfour began working as a test pilot for North American Aviation, Inc., 1 March 1936.
On 2 July 1938, he married Lois Tresa Watchman at Kingman, Arizona. They would have two children.
On 9 November 1951, Major Paul B. Balfour, U.S. Air Force, attached to the 1002nd Inspector General Group at Norton Air Force Base, California, was flying a North American VB-25J, 44-30955, a transport conversion of a B-25J-30-NC Mitchell medium bomber.
Shortly after takeoff, at about 10:00 a.m., the airplane developed engine trouble. Unable to return to Norton, Balfour attempted a belly landing at a small private airfield. Witness saw that the airplane’s left engine was idling, and its propeller was feathered. As he approached, the airplane was blocked by a windbreak of eucalyptus trees bordering U.S. Route 66. Balfour banked away from the trees but the B-25 crashed in an orange grove along Bloomington Avenue in Rialto, approximately 7 miles (11 kilometers) north of Norton.
Balfour, still buckled in his seat, was thrown clear of the burning wreck and landed in the street. One man on board was killed and two others seriously injured. Balfour died in a hospital three hours later. He was 41 years old. Major Balfour was buried at the Inglewood Park Cemetery, Inglewood, California.
18 November 1930: The prototype Boeing XP-9, Air Corps serial number A.C. 28-346, a single-seat, single-engine monoplane pursuit, made its first flight at Wright Field, Ohio.
This was Boeing’s first semi-monocoque aircraft, built of a sheet dural skin over metal formers. The Army Air Corps issued the contract 29 April 1928 and the aircraft was completed in September 1930, then shipped by railroad to the Army test base.
The XP-9 (Boeing Model 96) was a single-place, single-engine high-wing monoplane with fixed landing gear. It was 25 feet, 1.75 inches (7.665 meters) long. with a wingspan of 36 feet, 6 inches (11.125 meters) and height of 7 feet, 10.25 inches (2.394 meters). The prototype’s empty weight was 2,669 pounds (1,211 kilograms) and its maximum takeoff weight was 3,623 pounds (1,643 kilograms).
The pursuit prototype was powered by a pressurized-liquid-cooled, supercharged, 1,570.381-cubic-inch-displacement (25.734 liter) Curtiss Super Conqueror SV-1570-C dual-overhead camshaft (DOHC) 60° V-12 engine with 4 valves per cylinder. This engine was rated at 600 horsepower at 2,400 r.p.m. It weighed 920 pounds (417 kilograms).
The airplane had a maximum speed of 213 miles per hour (343 kilometers per hour). The service ceiling was 26,800 feet (8,169 meters). Armament was a combination of two machine guns, either one .30-caliber and one .50-caliber, or two .50 caliber, mounted one each side of the fuselage, firing forward.
The placement of the single high wing seriously restricted the pilot’s vision, making landings very dangerous. The airplane was highly unstable in flight. Increasing the size of the tail surfaces did little to improve this. After just 15 flight hours, the XP-9 was permanently grounded and was used as an instructional airframe.
The performance and handling of the XP-9 was considered to be so poor that an option to buy five pre-production models was canceled.
The XP-9’s sole redeeming quality was its method of construction, which has been almost universal since that time.
14 November 1974: The very first operational McDonnell Douglas F-15A Eagle air superiority fighters were delivered to the 555th Tactical Training Squadron, 58th Tactical Training Fighter Wing, at Luke Air Force Base, west of Phoenix, Arizona. The acceptance ceremony was presided over by President Gerald R. Ford.
“. . . I am here today to underscore to you and to the world that this great aircraft was constructed by the American people in the pursuit of peace. Our only aim with all of this aircraft’s new maneuverability, speed, and power is the defense of freedom.
“I would rather walk a thousand miles for peace than to have to take a single step for war.
“I am here to congratulate you: the United States Air Force, McDonnell Douglas, Pratt and Whitney, all of the many contractors and workers who participated in this very, very successful effort, as well as the pilots who have so diligently flight-tested the F-15 Eagle. All of you can underline my feeling that we are still pilgrims on this Earth, and there still is a place for pioneers in America today.”
—Gerald R. Ford, Jr., 38th President of the United States of America
The F-15A Eagle is a Mach 2.5+ fighter with outstanding acceleration and maneuverability. The F-15A was produced by McDonnell Douglas at St. Louis, Missouri, from 1972 to 1979. It is a single-seat, twin-engine, air superiority fighter. It is 63 feet, 9.0 inches (19.431 meters) long with a wingspan of 42 feet, 9.7 inches (13.048 meters) and overall height of 18 feet, 5.4 inches (5.624 meters). The F-15A has an empty weight of 25,870 pounds (11,734 kilograms) and its maximum takeoff weight (MTOW) is 44,497 pounds (20,184 kilograms).
The F-15A is powered by two Pratt & Whitney JTF22A-25A (F100-PW-100) afterburning turbofan engines. The F100 is a two-spool, axial-flow turbine engine with a 3-stage fan section; 10-stage compressor; single chamber combustion section; and 4-stage turbine (2 low- and 2 high-pressure stages). The engine has a Maximum Continuous Power rating of 12,410 pounds of thrust (55.202 kilonewtons); 14,690 pounds (65.344 kilonewtons, 30-minute limit; and a maximum 23,840 pounds (106.046 kilonewtons), 5-minute limit. The F100-PW-100 is 191 inches (4.851 meters) long, 46.5 inches (1.181 meters) in diameter, and weighs 3,035 pounds (1,376.7 kilograms).
The cruise speed of the F-15A Eagle is 502 knots (578 miles per hour/930 kilometers per hour). It has a maximum speed of 893 knots (1,028 miles per hour/1,654 kilometers per hour) at 10,000 feet (3,048 meters), and 1,434 knots (1,650 miles per hour/2,656 kilometers per hour) at 45,000 feet (13,716 meters). The ceiling is 63,050 feet (19,218 meters) at maximum power. It can climb at an initial 67,250 feet per minute (342 meters per second) from Sea Level, and with a thrust-to-weight ratio of 1.15:1, The F-15 can climb straight up. The Eagle’s combat radius is 638 nautical miles (734 statute miles/1,182kilometers).
The F-15A is armed with one General Electric M61A1 Vulcan 20mm rotary cannon with 938 rounds of ammunition, four AIM-7F Sparrow radar-guided missiles and four AIM-9 Sidewinder heat-seeking missiles. The fighter can also be armed with a Mk.82 500-pound or Mk. 84 2,000-pound bombs.
384 F-15A Eagles were built before production shifted to the improved F-15C version. As F-15Cs became operational, the F-15As were transferred to Air National Guard units assigned to defend U.S. continental airspace. The last F-15A was retired from service in 2009.
13 November 1942: Lieutenants Harold E. Comstock and Roger B. Dyar were fighter pilots assigned to the 63rd Fighter Squadron, 56th Fighter Group, at Bridgeport, Connecticut. They were often sent to test new P-47 Thunderbolt fighters at the Republic Aviation Corporation factory in nearby Farmingdale, New York. According to Wikipedia:
Because of the need to manufacture airplanes quickly and the close proximity to the Republic Aviation factory, active duty pilots were used for some of the test flights of the new P-47. On 13 November 1942, Lts. Comstock and Dyar were ordered to test a new type of radio antenna on the P-47C. Lt. Comstock climbed to an indicated altitude of 49,600 feet (15,118 meters) while trying to reach 50,000 feet. Due to poor response from the controls, he decided to let the aircraft fall off rather than risk a spin. He started to dive straight down and after passing below 40,000 feet he found that his controls had frozen. He then felt a bump and was unable to move the controls as the aircraft continued to dive. Even with maximum exertion, he was unable to move the control stick so he started to roll the trim tab back and after passing below 30,000 feet, the aircraft started to pull out of the dive and he recovered between 20,000 and 25,000 feet.
Lt. Dyar started his dive and encountered the same conditions. After landing, Lt. Comstock reported what happened and the chief designer of the P-47 Thunderbolt, Alexander Kartveli, questioned Lt. Comstock at length and made numerous calculations. Republic Aviation soon issued a press release claiming that Lts. Comstock and Dyar had exceeded the speed of sound. This was picked up in the national media and also drawn in Ripley’s Believe It or Not!. Soon after the press release, the 56th Fighter Group received a telegram from Gen. Henry “Hap” Arnold that “there would be no more discussion about the dive.” The actual speed attained was probably less than the speed of sound but this speed which caused the flight controls to lock up was referred to as “compressibility.” This effect was encountered by many pilots flying in combat but training and proper procedures allowed them to recover from it. In 1959, the Air Force published “A Chronology of American Aerospace Events” and included an entry for 15 November 1942 which stated “Lts. Harold Comstock and Roger Dyar set a new speed record for airplanes when they power-dived their P-47 fighters at 725 mph from 35,000 feet over an east coast air base.” While the Air Force acknowledged the speed of 725 miles per hour, it is not known whether the P-47 could actually exceed the speed of sound in a dive. Capt. Roger Dyar was killed in action on 26 June 1943. — Wikipedia
The Los Angeles Times reported:
Plane Diving 725 m.p.h. Surpasses Speed of Sound
Bulletlike, 12-Mile-Minute Plunge of Thunderbolt P-47 Froze Control Sticks, Intrepid Army Pilots Report
Farmingdale, N.Y., Dec. 2. (AP)—How two Army lieutenants dived their Republic P-47 Thunderbolt fighter plane at a speed of 725 miles an hour—more than 12 miles a minute and faster than the high-altitude speed of sound—was disclosed today.
The terrific speed—perhaps faster than any human being has traveled before—froze their control sticks, the pilots reported, causing them to resort to the use of emergency cranks to move the elevator tabs and pull their ships out of the dive.
“My body was pushed back against the rear armor plate and I had a feeling that any second the plane was going to pull away from me and leave me stranded right there, five miles above the ground. It;s a breathless feeling, your stomach curls up; it’s something like stepping from a hot shower to a cold one,” Lieut. Roger Dyar, one of the pilots, said.
“When I rolled back on the tabs,” Lieut. Harold Comstock said, “the plane shuddered as though it had been hit by a truck.”
Both pilots became air cadets in 1941. Lieut. Comstock is from Fresno, Cal., and Lieut. Dyar from Lowell, O.
—Los Angeles Times, Vol. LXI, Thursday, 3 December 1942, Page 1, Columns 4 and 5
Almost certainly, the diving Thunderbolts did not exceed the speed of sound:
In July 1944 Major [Frederic Austin] Borsodi [Chief, Fighter Test Branch, Army Air Forces Material Command, Wright Field] made a number of full power vertical dives from 40,000 feet in a North American P-51D to assess the compressibility effects on the aircraft’s handling. He achieved a maximum Mach number of 0.86, at which point severe buffeting of the empennage was noted. . . many World War II pilots remained firmly convinced that they had taken their propeller-driven fighters supersonic in steep dives, often as local shock waves rattled their craft and caused the angle of those dives to become uncontrollably steeper. More often than not the center of lift moved aft on their wings, and Mach-induced turbulence blanketed the normal control surfaces on the tail. For the lucky ones, the descent into denser air slowed the airplane, while the higher temperatures at lower altitude meant that the Mach number for a given true airspeed was lower. Consequently, local shock waves tended to disappear. A normal recovery as from any steep dive, could usually be effected. . . the later [Supermarine] Spitfires, with a demonstrated ceiling of 45,000 feet, a much thinner wing of elliptical planform, and a lower profile liquid-cooled engine, could never register a maximum speed greater than 0.9 Mach number. That is the highest recorded speed, by a substantial margin of any propeller driven fighter. Oh yes, in the course of one such dive, on entering the denser air around 20,000 feet, the Spitfire’s propeller and much of the engine cowling parted company with the rest of the aircraft. Getting to 0.90 Mach number wasn’t easy. . . the speed of sound at sea level and 59° Fahrenheit is 761 miles per hour. At an altitude of 40,000 feet, where our standard atmosphere charts tell us that the temperature is -67° Fahrenheit, sound travels at 662 miles per hour.
— Aces Wild: The Race For Mach 1, by Al Blackburn, Scholarly Resources, Inc., Wilmington, Delaware, at Pages 6–7, 24–27.
Harold Elwood Comstock was born 20 December 1920 at Fresno, California. He was the son of Clinton Elwood Comstock, a telephone company repairman, and Leona M. Sutherland Comstock. He graduated from Roosevelt High School in Fresno, in February 1939. Comstock then entered Fresno State College. He was a member of the F.S.C. Pilots Club and the Aero Mechanics Club.
Harold Comstock was appointed an Aviation Cadet, Air Corps, Army of the United States (A.U.S.), 10 October 1941. He was 5 feet, 10 inches (1.78 meters) tall and weighed 149 pounds (67.6 kilograms). After completing flight training, on 3 July 1942 Comstock was commissioned as a second lieutenant, Air Reserve. Comstock was promoted to first lieutenant, A.U.S., 29 May 1943. Lieutenant Comstock advanced to the rank of captain, A.U.S., on 12 March 1944, and to major, A.U.S., 17 September 1944. On 3 July 1945, Major Comstock’s permanent Air-Reserve rank was advanced to first lieutenant.
Harold Comstock flew two combat tours in Europe with the 56th Fighter Group during World War II. He completed his second tour as commanding officer of the group’s 63rd Fighter Squadron. He flew 138 combat missions and is officially credited with destroying 5 enemy aircraft in aerial combat, with 2 probably destroyed and 3 damaged, and another 3 destroyed on the ground.
During his World War II service, Major Comstock was awarded the Distinguished Flying Cross with three oak leaf clusters (four awards); the Air Medal with 11 oak leaf clusters (12 awards) and the Purple Heart.
Lieutenant Comstock married Miss Barbara Lucille Joint, also from Fresno, 10 June 1942 at Bridge City, Texas. They would have two children, Harold Eric Comstock, and Roger Joseph Comstock.
On 16 May 1947, Major Comstock was promoted to the rank of Lieutenant Colonel, Air-Reserve. On 10 October 1947, Comstock’s permanent military rank became fist lieutenant, Air Corps, with date of rank retroactive to 3 July 1945. When the United States Air Force was established as an independent branch of the U.S. Armed Forces, Comstock’s commission was converted. (1st Lieutenant, No. 7779.)
During the Vietnam War, Lieutenant Colonel Comstock commanded the 481st Tactical Fighter Squadron, 27th Tactical Fighter Wing from 1965 to 1968. He flew another 132 combat missions in the North American Aviation F-100D Super Sabre, and 38 as commander of an airborne command and control unit of the 7th Airborne Command and Control Squadron. Colonel Comstock’s final assignment was as commanding officer, 602nd Tactical Control Group, Bergrstom Air Force Base, southeast of Austin, Texas.
Colonel Comstock retired from the Air Force on 30 September 1971. He was twice awarded the Legion of Merit, and he held the Distinguished Flying Cross with six oak leaf clusters, a Purple Heart, and 17 Air Medals.
Harold E. Comstock died at Clovis, California in 2009 at the age of 88 years. He was buried at Fresno Memorial Gardens, Fresno, California.
The Republic P-47 Thunderbolt was the largest single-engine fighter that had yet been built. The first P-47C variant was completed 14 September 1942, only one month before Bunny Comstock’s famous dive. An early change (P-47C-1) was the addition of 8 inches (0.203 meters) to the forward fuselage for improved handling. The P-47C-5-RE was 36 feet, 1-3/16 inches (11.003 meters) long with a wingspan of 40 feet, 9-5/16 inches (12.429 meters) The overall height was 14 feet 3-5/16 inches (4.351 meters). The fighter’s empty weight was 9,900 pounds (4,490.6 kilograms) and maximum gross weight was 14,925 pounds (6,769.9 kilograms).
The P-47C was powered by an air-cooled, supercharged, 2,804.4-cubic-inch-displacement (45.956 liter) Pratt & Whitney Double Wasp TSB1-G (R-2800-21) two-row, 18-cylinder radial engine with a compression ratio of 6.65:1. The R-2800-21 had a Normal Power rating of 1,625 horsepower at 2,550 r.p.m. to 25,000 feet (7,620 meters) and a Takeoff/Military Power rating of 2,000 horsepower at 2,700 r.p.m. to an altitude of 25,000 feet (7,620 meters). A large General Electric turbosupercharger was mounted in the rear of the fuselage. Internal ducts carried exhaust gases from the engine to drive the turbocharger and the supercharged air was then carried forward to supply the engine. The engine drove a 12 foot, 2 inch (3.708 meter) diameter four-bladed Curtiss Electric propeller through a 2:1 gear reduction. The R-2800-21 was 6 feet, 3.72 inches (1.923 meters) long, 4 feet, 4.50 inches (1.340 meters) in diameter, and weighed 2,265 pounds (1,027 kilograms). Approximately 80% of these engines were produced by the Ford Motor Company. It was also used as a commercial aircraft engine, with optional propeller gear reduction ratios.
The P-47C had a maximum speed in level flight of 433 miles per hour (697 kilometers per hour) at 30,000 feet (9,144 meters). The service ceiling was 42,000 feet (12,802 meters), and it could climb to 15,000 feet (4,572 meters) in 7 minutes, 12 seconds. It had a maximum range of 1,250 miles (2,012 kilometers) with external fuel tanks.
The Thunderbolt was armed with eight Browning AN-M2 .50-caliber machine guns, four in each wing, with 3,400 rounds of ammunition. It could also carry external fuel tanks, rockets and bombs. The structure of the P-47 could be described as “robust” and it was heavily armored.
602 P-47Cs were built in the five months before the P-47D entered production. A total of 15,683 Thunderbolts were built; more than any other Allied fighter type. In aerial combat it had a kill-to-loss ratio of 4.6:1. The amount of damage that the airplane could absorb and still return was remarkable. The P-47, though, really made its name as a ground attack fighter, destroying aircraft, locomotives, rail cars, and tanks by the many thousands. It was one of the most successful aircraft of World War II.