Tag Archives: Clarence S. Irvine

11 December 1945

Bell-Atlanta B-29B-60-BA Superfortress 44-84061, the Pacusan Dreamboat. (U.S. Air Force)
Bell-Atlanta B-29B-60-BA Superfortress 44-84061, the Pacusan Dreamboat. (U.S. Air Force)

11 December 1945: Three days after Lieutenant Colonel Henry E. Warden and Captain Glen W. Edwards set a transcontinental speed record flying a prototype Douglas XB-42 from Long Beach, California, to Washington, D.C., in 5 hours, 17 minutes, Colonel Clarence S. Irvine and the crew of the B-29 Pacusan Dreamboat also set a record, flying from Burbank, California to overhead Floyd Bennett Field, New York, in 5 hours, 27 minutes, 8 seconds. The average speed for the 2,464-mile flight was 450.38 miles per hour (724.82 kilometers per hour).

Lieutenant General Clarence S. Irvine, U.S. Air Force

Irvine was Deputy Chief of Staff, Pacific Air Command, 1944–1947. He flew the Pacusan Dreamboat on several record-setting flights, including Guam to Washington, D.C., and Honolulu, Hawaii to Cairo, Egypt. He rose to the rank of lieutenant general in the United States Air Force, and served as Deputy Chief of Staff for Materiel.

Pacusan Dreamboat was a Bell Aircraft Corporation B-29B-60-BA Superfortress, built at Marietta, Georgia. The B-29B was a lightweight variant of the B-29, intended for operation at lower altitudes. It did not have the four power gun turrets and their .50-caliber machine guns. A radar-directed 20 mm cannon and two .50-caliber machine guns in the tail were the only defensive weapons. Much of the standard armor plate was also deleted. Pacusan Dreamboat was further lightened. The tail guns were removed and the tail reshaped.

The B-29B was equipped with four air-cooled, fuel-injected Wright R-3350-CA-2 Duplex Cyclone two-row 18 cylinder radial engines and specially-designed propellers. The engine nacelles were modified for improved cooling.

The Superfortress had been lightened to an empty weight of 66,000 pounds (29,937 kilograms). A standard B-29B weighed 69,000 pounds (31,298 kilograms) empty and 137,000 pounds (62,142 kilograms) fully loaded. Additional fuel tanks installed on the Dreamboat were able to carry 10,000 gallons (37,854 liters) of gasoline.

Colonel Clarence S. Irvine (standing, left) with the crew of Pacusan Dreamboat: W.J.Benett, G.F.Broughton, Dock West, W.S. O’Hara, F.S. O’Leary, K.L. Royer, F.J.Shannon, J.A. Shinnault, G.R. Stanley. (FAI)
Colonel Clarence S. Irvine (standing, left) with the crew of Pacusan Dreamboat: W.J. Benett, G.F. Broughton, Dock West, W.S. O’Hara, F.S. O’Leary, K.L. Royer, F.J. Shannon, J.A. Shinnault, G.R. Stanley. (FAI)

© 2015, Bryan R. Swopes

1 August 1939

The flight crew of the FAI World Altitude Record-setting Boeing Y1B-17A. Left to right: Captain Pearl H. Robey, Captain Clarence S. Irvine and R. Swofford. (FAI)

1 August 1939: Captains Clarence S. Irvine and Pearl H. Robey, United States Army Air Corps, used the Boeing Y1B-17A Flying Fortress (Model 299F), serial number 37-369, to set a Fédération Aéronautique Internationale (FAI) World Record for Altitude with a 5,000 Kilogram Payload. The bomber climbed to 10,371 meters (34,026 feet) with a payload of 11,023 pounds.¹ ²

On the same day, Irvine and Robey flew the Y1B-17 from Dayton, Ohio to St. Jacob, Illinois, setting an FAI World Record for Speed Over 1,000 Kilometers with a 5,000 Kilogram Payload, averaging 417.46 kilometers per hour (259.40 miles per hour).³

The flight crew of the FAI World Speed Record-setting Boeing Y1B-17A. Left to Right: Capatain C.J. Crane, P.G. Miller, Captain Clarence S. Irvine and Captain pearl H. Robey. (FAI)
The flight crew of the FAI World Speed Record-setting Boeing Y1B-17A. Left to Right: Captain Carl J. Crane, P.G. Miller, Captain Clarence S. Irvine and Captain Pearl H. Robey. (FAI)

The single Y1B-17A (Boeing Model 299F) was originally ordered as a static test article, but when that was determined to be unnecessary, it was used as an engine test aircraft. It was equipped with four 1,823.129-cubic-inch-displacement (29.875 liter) air-cooled, supercharged, Wright R-1820-51 (Cyclone G59) single-row nine-cylinder radial engines. Moss/General Electric turbo-superchargers were installed, initially on top of the wings, but were moved to the bottom of the engine nacelles.

Boeing Y1B-17A 37-369. (FAI)

The supercharged Wright R-1820-39 (Cyclone R-1820-G5) engines of the YB-17s were rated at 805 horsepower at 2,100 r.p.m., at Sea Level, 775 horsepower at 14,000 feet (4,267 meters), and 930 horsepower at 2,200 r.p.m., for take off. By contrast, the YB-17A’s R-1820-51 engines were rated at 800 horsepower at 2,100 r.p.m. at Sea Level, and 1,000 horsepower at 2,200 r.p.m. for take off. But the turbochargers allowed the engines to maintain their Sea Level power rating all the way to 25,000 feet (7,620 meters). Both the -39 and -51 engine had a 16:11 propeller gear reduction ratio. The R-1820-51 was 3 feet, 9.06 inches (1.145 meters) long, 4 feet, 6.12 inches (1.375 meters) in diameter, and weighed 1,200.50 pounds (544.54 kilograms). 259 were produced by Wright between September 1937 and February 1940.

Boeing Y1B-17A 37-369. (U.S. Air Force)

The turbo-superchargers installed on the YB-17A greatly improved the performance of the bomber, giving it a 55 mile per hour (89 kilometer per hour) increase in speed over the supercharged YB-17s, and increasing the bomber’s service ceiling by 7,000 feet (2,132 meters). The turbo-superchargers worked so well that they were standard on all following B-17 production models.

Boeing Y1B-17A 37-369. (U.S. Air Force photo)

The Boeing Y1B-17A was 68 feet, 9 inches (20.955 meters) long with a wingspan of 103 feet, 9–3/8 inches (31.633 meters) and height of 14 feet, 11–5/16 inches (4.363 meters). Its empty weight was 26,520 pounds (12,029 kilograms). The maximum gross weight was 45,650 pounds (20,707 kilograms)

The Model 299F had a cruise speed of 230 miles per hour (370 kilometers per hour), a maximum speed of 271 miles per hour (436 kilometers per hour) at Sea Level and 295 miles per hour (475 kilometers per hour) at 25,000 feet (7,620 meters). The service ceiling was 38,000 feet (11,582 meters). The maximum range was 3,600 miles (5,794 kilometers). Carrying a 4,000 pound (1,814 kilogram) load of bombs, the range was 2,400 miles (3,862 kilometers).

The Y1B-17A could carry eight 600 pound (272 kilogram) bombs in an internal bomb bay. Defensive armament consisted of five .30-caliber machine guns.

Following the engine tests, 37-369 was re-designated B-17A.

The Boeing Y1B-17A in flight near Mt. Rainier on 28 February 1938. (U.S. Air Force)

¹ FAI Record File Number 8318

² This record-setting flight was dramatized in the motion picture “Test Pilot,” (1938, Metro-Goldwyn-Mayer) with Clark Gable, Spencer Tracy and Myrna Loy. This movie is now 80 years old and has a melodramatic plot, but is well worth seeing for aviation history enthusiasts.

³ FAI Record File Number 10443

© 2018, Bryan R. Swopes