17 December 1984: At Dobbins Air Force Base, Georgia, Jesse Thomas Allen set a Fédération Aéronautique Internationale (FAI) World Record for the Greatest Payload Carried to a Height of 2,000 Meters (6,562 feet), lifting 111,461.57 kilograms (245,730.70 pounds) aboard a Lockheed C-5A Galaxy.¹
During the same flight, Allen established a National Aeronautic Association United States National Record for the Greatest Recorded Weight at Which Any Airplane Has Ever Flown of 920,836 pounds (417,684 kilograms), after the Galaxy had refueled in flight.
30 July 1939: Major Caleb Vance Haynes, Air Corps, United States Army, with Captain William D. Old, Master Sergeant Adolph Cattarius and Staff Sergeant William J. Heldt, flew the Boeing XB-15 experimental long range heavy bomber to a Fédération Aéronautique Internationale (FAI) World Record for Greatest Payload Carried to a Height of 2,000 meters. The XB-15 carried 14,135 kilograms (31,162 pounds) to an altitude of 2,000 meters (6,562 feet) over Fairfield, Ohio.¹ The flight set a second record by carrying 10,000 kilograms (22,046 pounds) to an altitude of 8,228 feet (2,508 meters).² Both records were certified by the National Aeronautic Association, the American organization representing the FAI.
The Boeing Model 294, designated XB-15 by the Air Corps, was an experimental airplane designed to determine if a bomber with a 5,000 mile range was possible. It was designed at the same time as the Model 299 (XB-17), which had the advantage of lessons learned by the XB-15 design team. The XB-15 was larger and more complex than the XB-17 and took longer to complete. It first flew more than two years after the prototype B-17.
Designers had planned to use an experimental 3,421.194-cubic-inch-displacement (56.063 liter) liquid-cooled, supercharged and turbosupercharged Allison V-3420 twenty-four cylinder, four-bank “double V” engine. It produced a maximum of 2,885 horsepower at 3,000 r.p.m. The engine was not available in time, however, and four air-cooled Pratt & Whitney R-1830 (Twin Wasp) engines were used instead. With one-third the horsepower, this substitution left the experimental bomber hopelessly underpowered as a combat aircraft. (The Douglas XB-19 was retrofitted with V-3420s in 1942, and re-designated XB-19A.)
The XB-15 was a very large four-engine mid-wing monoplane with retractable landing gear. It was of aluminum monocoque construction with fabric-covered flight control surfaces. The XB-15 had a ten-man crew which worked in shifts on long duration flights.
The prototype bomber was 87 feet, 7 inches (26.695 meters) long with a wingspan of 149 feet (45.415 meters) and overall height of 18 feet, 1 inch (5.512 meters). The airplane had an empty weight of 37,709 pounds (17,105 kilograms) and maximum takeoff weight of 70,706 pounds (32,072 kilograms)—later increased to 92,000 pounds (41,730 kilograms).
The XB-15’s wings used a symmetrical airfoil and were very highly tapered (4:1 from root to tip). They had an angle of incidence of 4½° and 4½° dihedral. The total area was 2,780 square feet (258.271 square meters). A contemporary aeronautical publication wrote, “The airfoil provides constant center of pressure, minimum profile drag with flaps up and high maximum lift with flaps down.” The XB-15’s wings were adapted by Boeing for the Model 314 Clipper flying boat.
As built, the XB-15 was equipped with four air-cooled, supercharged, 1,829.39-cubic-inch-displacement (29.978 liter) Pratt & Whitney R-1830-11 (Twin Wasp S1B3-G) two-row 14-cylinder radial engines with a compression ratio of 6.7:1. The R-1830-11 was rated at 850 horsepower at 2,450 r.p.m. and 5,000 feet (1,524 meters), and 1,000 horsepower at 2,600 r.p.m. for take off. They turned three-bladed controllable-pitch propellers through a 3:2 gear reduction. The R-1830-11 was 4 feet, 8.66 inches (1.439 meters) long with a diameter of 4 feet, 0.00 inches (1.219 meters), and weighed 1,320 pounds (599 kilograms).
The experimental airplane had a cruise speed of 152 miles per hour (245 kilometers per hour) at 6,000 feet (1,829 meters), and a maximum speed of 200 miles per hour ( kilometers per hour) at 5,000 feet (1,524 meters). The service ceiling was 18,900 feet (5,761 meters) and maximum range was 5,130 miles (8,256 kilometers).
The bomber could carry a maximum of 12,000 pounds (5,443 kilograms) of bombs in its internal bomb bay, and was armed with three .30-caliber and three .50-caliber machine guns for defense .
Only one XB-15 was built. During World War II it was converted to a transport and re-designated XC-105. In 1945 35-277 was stripped and abandoned at Albrook Field, Territory of the Canal Zone, Panama.
8–19 May 1946: Over an 11-day period, 20th Air Force Boeing B-29 Superfortresses based in the Marianas Islands set a series of twelve payload, altitude and speed records. These records were certified for the Fédération Aéronautique Internationale (FAI) and National Aeronautic Association (NAA) by Charles S. Logsden, the association’s official timer and records keeper. All of the record flights originated from Harmon Field on the Island of Guam.
On 8 May, a B-29 flown by Arthur A. Pearson carried a 10 000 kilogram (22,046 pounds) payload to an altitude of 12 668 meters (41,562 feet). [FAI Record File Number 10415] Other members of the flight crew were Vernon L. Dalbey, R.S. Strasburg, I. F. Bork, J.T Collins, and J. Friedberg.
Three days later, 11 May 1946, a B-29 under the command of Colonel Beverly Howard Warren took off from Harmon Field with a payload of 15 166 kilograms (33,435 pounds) and climbed to a height of 2 000 meters (6,562 feet). [FAI Record File Number 8738] The bomber then continued to climb until it reached an altitude of 12 046 meters (39,521 feet). [FAI Record File Number 8736] Colonel Warren (later, Brigadier General) was chief of special projects, headquarters, Pacific Air Command, United States Army (PACUSA). Other members of his crew were J.R. Dale, W.D. Collier, G.S. Fish, and T.H. Hall.
On 13 May, Elbert D. Reynolds, Brian P. Robson, John G. Barnes, T. Madden, K. H. Morehouse, W. C. Flynn,and L. Lentowski flew their Superfortress with a payload of 2 000 kilograms (4,409 pounds) to an altitude 14 180 meters (46,522 feet). [FAI File Number 8738]
The following day, 14 May, John B. Tobison’s B-29 carried a 5 000 kilogram (11,023 pounds) payload to an altitude of 13 793 meters (45,253 feet). [FAI Record File Number 8243] The members of his crew were A.W. Armistead, R.M. Beattie, E.J. Joyce, R.F. Johnson and M.R. Genta.
On 15 May, Finlay Ross and his crew, which included Dougall M. Davis, flew their B-29 to an altitude of 14 603 meters (47,910 feet) with a payload of 1 000 kilograms (2,205 pounds). [FAI Record File Number 8194]
17 May: E.M Graboski flew his B-29 around a closed circuit for a distance of 1 000 kilometers (621.37 miles) with a 5 000 kilogram (11,023.1 pounds) payload, with an average speed of 594,97 km/h (369.697 m.p.h.). [FAI Record File Number 10424] Continuing around the closed circuit for a total of 2 000 km (1,242.74 mi.), Grabowski and his crew set records for an average speed of 588.46 km/h (365.652 m.p.h.) with a 1 000 kg (2,204.6 lbs.) payload [FAI File #13329]; 2 000 kg (4,409.3 lbs.) [FAI # 13330]; and 5 000 kg (11,023.1 lbs.). [FAI # 10425] Grabowski’s crew members were J.J. Liset, D.P. Kelly, O.W. Lambert, F.M. Polmotier.
Finally. on 19 May 1946, J.D. Bartlett, with his crewmen, William Murray, C.M. Youngblood, Don J. Shrader, and R.F. Wilson, flew their Superfortress around a closed circuit if 1 000 km (621.37 mi.) with a payload of 10 000 kg (22,046 lbs.) at an average speed of 575,71 km/h (357.730 m.p.h.); [FAI # 10408]; and 2 000 km (1,243.74 mi.) at 574,59 km/h (357.034 m.p.h.) (FAI # 10409]
The B-29 Superfortress was the most technologically advanced—and complex—aircraft of World War II. It required the manufacturing capabilities of the entire nation to produce. Over 1,400,000 engineering man-hours had been required to design the prototypes.
The Superfortress was manufactured by Boeing at Seattle and Renton, Washington, and Wichita, Kansas; by the Glenn L. Martin Company at Omaha, Nebraska; and by Bell Aircraft Corporation, Marietta, Georgia.
There were three XB-29 prototypes, 14 YB-29 pre-production test aircraft, 2,513 B-29 Superfortresses, 1,119 B-29A, and 311 B-29B aircraft. The bomber served during World War II and the Korean War and continued in active U.S. service until 1960. In addition to its primary mission as a long range heavy bomber, the Superfortress also served as a photographic reconnaissance airplane, designated F-13, a weather recon airplane (WB-29), and a tanker (KB-29).
The B-29 was operated by a crew of 11 to 13 men. It was 99 feet, 0 inches (30.175 meters) long with a wingspan of 141 feet, 3 inches (43.068 meters). The vertical fin was 27 feet, 9 inches (8.305 meters) high. The airplane’s empty weight was 71,500 pounds (32,432 kilograms). Its maximum takeoff weight of 140,000 pounds (63,503 kilograms).
The B-29’s wings had a total area of 1,720 square feet (159.8 square meters). They had an angle of incidence of 4° and 4° 29′ 23″ dihedral. The leading edges were swept aft to 7° 1′ 26″.
The B-29 was powered by four air-cooled, turbocharged and supercharged, 3,347.66-cubic-inch-displacement (54.858 liter) Wright Aeronautical Division Cyclone 18 (also known as the Duplex-Cyclone) 670C18BA4 (R-3350-23A) two-row, 18-cylinder radial engines. These had a Normal Power rating of 2,000 horsepower at 2,400 r.p.m., and 2,200 horsepower at 2,800 r.p.m., for takeoff. They drove 16 foot, 7 inch (5.055 meter) diameter, four-bladed, Hamilton Standard constant-speed propellers through a 0.35:1 gear reduction. The R-3350-23A was 6 feet, 4.26 inches (1.937 meters) long, 4 feet, 7.78 inches (1.417 meters) in diameter and weighed 2,646 pounds (1,200 kilograms).
The maximum speed of the B-29 was 353 knots (406 miles per hour/654 kilometers per hour) at 30,000 feet (9,144 meters), though its normal cruising speed was 216 knots (249 miles per hour/400 kilometers per hour) at 25,000 feet (7,620 meters). The bomber’s service ceiling was 40,600 feet (12,375 meters) and the maximum ferry range was 4,492 nautical miles (5,169 statute miles/8,319 kilometers).
The Superfortress could carry a maximum of 20,000 pounds (9,072 kilograms) of bombs in two bomb bays. For defense, it was armed 12 Browning AN-M2 .50-caliber machine guns in four remote, computer-controlled gun turrets and a manned tail position. The bomber carried 500 rounds of ammunition per gun. (Some B-29s were also armed with an M2 20 mm autocannon at the tail.)
A number of B-29 Superfortresses are on display at locations around the world, but only two, the Commemorative Air Force’s B-29A-60-BN 44-62070, Fifi, and B-29-70-BW 44-69972, Doc, are airworthy. (After a lengthy restoration, Doc received its Federal Aviation Administration Special Airworthiness Certificate, 19 May 2016.)