Tag Archives: Test Flight

20 March 1945

Tony LeVier and the first prototype Lockheed XP-80A, 44-83021, in flight over southern California’s high desert, 1945. (Lockheed Martin)
Anthony W. (“Tony”) LeVier

20 March 1945: Tony LeVier was conducting a test flight of the first prototype Lockheed XP-80A, 44-83021, near Muroc Army Air Field (now known as Edwards Air Force Base).

The XP-80A was developed from the original XP-80 prototype, but was larger to incorporate a more powerful General Electric I-40 turbojet engine in place of the original Allis-Chalmers J36 (a license-built version of the British Halford H.1B).

The I-40 was a single-shaft turbojet which used a double-inlet, single-stage, centrifugal-flow compressor, fourteen straight-through combustors and a single-stage axial-flow turbine. The engine had a maximum speed of 11,500 r.p.m. and produced 4,000 pounds of thrust (17.79 kilonewtons). The I-40 was 48 inches (1.22 meters) in diameter and weighed 1,820 pounds (826 kilograms). The I-40 would be produced by Allison Division of General Motors as the J33 series.

General Electric I-40 turbojet engine cross section. (NASA)

At 15,000 feet (4,572 meters), LeVier put the XP-80A into a dive, intending to level off at 10,000 feet (3,048 meters) for a high-speed run. However, at 11,000 feet (3,353 meters), the single-stage turbine inside the jet engine failed and fragments tore through the prototype’s fuselage. The tail section of the airplane was cut off and the XP-80A went out of control.

An example of a turbine failure in a Lockheed P-80. (San Diego Air and Space Museum)

The XP-80A was not equipped with an ejection seat and LeVier had difficulty getting out, but finally escaped at about 4,000 feet (1,219 meters).

44-83021 crashed near the town of Rosamond and was completely destroyed. Tony LeVier’s parachute was swinging and he was severely injured when he hit the ground. His injuries kept him from flying for the next six months.

Lockheed XP-80A 44-83021 (U.S. Air Force)
Lockheed XP-80A 44-83021 (U.S. Air Force)

The Lockheed XP-80A was a single-place, single engine prototype fighter. It was 34 feet, 6 inches (10.516 meters) long with a wingspan of 39 feet, 0 inches (11.887 meters) and overall height of 11 feet, 4 inches (3.454 meters). It had an empty weight of 7,225 pounds (3,277 kilograms) and gross weight of 9,600 pounds (4,354 kilograms).

Armament consisted of six Browning .50-caliber AN-M2 machine guns with 300 rounds of ammunition per gun.

Two XP-80As were built. These were followed by twelve YP-80A Shooting Star service test aircraft. The Lockheed P-80A Shooting Star was ordered into production with an initial contract for 500 aircraft. This was soon followed by a second order for 2,500 fighters.

Wreckage of XP-80A 44-83021 loaded on a flat bed trailer. (U.S. Air Force)
Wreckage of XP-80A 44-83021 loaded on a flat bed trailer. (U.S. Air Force)

© 2019, Bryan R. Swopes

Facebooktwittergoogle_plusredditpinterestlinkedinmailby feather

18 March 1939

Boeing Model 307 Stratoliner NX19901 taking of at Boeing Field, Seattle, Washington. (San Diego Air & Space Museum Archives)

18 March 1939: At 12:57 p.m., Pacific Standard Time (19:47 G.M.T.), the Boeing Model S-307 Stratoliner, NX19901, took off from Boeing Field, Seattle, Washington, on Test Flight No. 19. Julius Augustus Barr was the pilot in command.

The S-307, Boeing serial number 1994, was a prototype four-engine, pressurized commercial airliner. It had first flown on 31 December 1938, with Boeing’s Chief of Flight Test, Edmund Turney (“Eddie”) Allen, as first pilot (the Pilot in Command), and Julius Barr as his copilot. Allen had flown the first eighteen flights. “The performance of aircraft NX 19901 on flights prior to Test Flight No. 19 had either met or exceeded the manufacturer’s estimates.”

Julius Barr was employed by Boeing as a test pilot, 16 November 1938. Following Flight Test No. 15, Allen approved Barr to act as first pilot on the Model 307. He first served as the pilot in command of NX19901 on 21 January 1939. This was a taxi test, with the Stratoliner never leaving the ground. Barr first flew the airplane nearly two months later, 16 March 1939, with copilot Earl Alvin Ferguson. Barr made two more flights on 17 March. Harlan Hull, Chief Pilot of Transcontinental and Western Air, Inc., flew as copilot.

At takeoff on 18 March 1939, Barr had only 2 hours, 6 minutes as pilot in command of the Boeing 307; and 17 hours, 55 minutes as second in command. He had flown as an observer aboard NX19901 for 1 hour, 52 minutes.

There were ten persons on board the Stratoliner for Test Flight No. 19. In addition to Julius Barr as P.I.C., the designated copilot was Earl Ferguson. There were two alternate copilots, Harlan Hull and Benjamin J. Pearson, an assistant sales manager for Boeing. Ralph LaVenture Cram was first aerodynamcist, assisted by John Kylstra. William C. Doyle served as oscillograph operator, and Harry T. West, Jr., was the engineering officer. These were all Boeing employees. Pieter Guillonard, technical director of Koninklijke Luchtvaart Maatschappij N.V. (KLM Royal Dutch Airlines), acted as recorder and photographer, while Albert Gillis von Baumhauer, an engineer with the Luchtvaartdienst (the Dutch Aviation Authority), acted as an assistant aerodynamicist.

Albert G. von Baumhauer

Specialized test equipment had been installed at the copilot’s position. For this reason, Von Baumhauer, rather than the designated copilot, Ferguson, was in the copilot’s seat during this test flight. (Von Baumgartner held a Dutch private pilot certificate, issued 28 November 1931. Since that time, he had flown only 116 hours, and had no experience flying multi-engine aircraft. He was not qualified to act as copilot.)

Guillonard and Von Baumhauer had recommended a series of tests to be conducted on Test Flight No. 19, including observing the airplane’s behavior following an engine cut on takeoff with no rudder input; a series of side slips and stall tests. Von Baumhauer had emphasized “complete stalls” rather than initiating recovery when stall was detected.

After takeoff, NX19901 climbed to 10,000 feet (3,048 meters) and at 140 miles per hour (225 kilometers per hour) a series of static longitudinal stability tests were performed. According to the test flight plan, side slips were to be investigated next.

Boeing 307 Stratoliner NX19901 with both propellers on right wing feathered. Note the rudder deflection. (Boeing)

     “At 1:12 P.M. (PST) a radio message was transmitted from NX 19901 to the Boeing Aircraft Company radio station located at Seattle, Washington, which message gave the position of the aircraft as being between Tacoma Washington and Mount Rainier at an altitude of 11,000 feet. Some two or three minutes later, while flying at a comparatively slow rate of speed in the vicinity of Alder, Washington, the aircraft stalled and began to spin in a nose down attitude. After completing two or three turns in the spin, during which power was applied, it recovered from the spin and began to dive. The aircraft partially recovered from the dive at an altitude of approximately 3,000 feet above sea level, during which recovery it began to disintegrate. Outboard sections of the left and right wings failed upward and broke entirely loose from the aircraft. Major portions of the vertical fin and portions of the rudder were carried away by wing wreckage. The outboard section of the left elevator separated from the stabilizer and both fell to the ground detached. The right horizontal tail surface, being held on by the fairing long the top surface and also by the elevator trim tab cables, remained with the fuselage. The No. 1 engine nacelle also broke loose from the aircraft and fell to the ground separately. The main body of the aircraft settled vertically and struck the ground in an almost level attitude both longitudinally and laterally at a point approximately 1,200 feet above sea level. Watches and clocks aboard the aircraft, which were broken by the force of the impact, indicated the time of the accident at approximately 1:17 p.m. (PST).”

AIR SAFETY BOARD REPORT, at Pages 34–35.

Diagram of probable flight path of NX19901 from Air Safety Board report.

All ten persons aboard were killed in the crash. The Stratoliner was destroyed. Because of the water ballast in the main fuel tanks, there was no post crash fire.

Wreckage of Boeing Model 307 Stratoliner NX19901, right rear quarter.
Wreckage of Boeing Model 307 Stratoliner NX19901, right front quarter.
Wreckage of Boeing Model 307 Stratoliner NX19901 near Alder, Washington
Wreckage of Boeing Model 307 Stratoliner NX19901 near Alder, Washington. (SDASM)
Wreckage of Boeing Model 307 Stratoliner NX19901, left front quarter.

During the crash investigation it was found that two B-17s had previously been spun. The first,

“. . . while flying with a gross load of about 42,000 pounds at an altitude of 14,000 feet, went into an inadvertent spin and made two complete turns before recovery was effected. During the pull-out from the ensuing dive, permanent distortion occurred in the structure of both wings, necessitating the installation of new wings on the aircraft.

     “In the second of these experiences, a similar ship was intentionally permitted to enter a spin following a complete stall. The controls were immediately reversed and the aircraft responded promptly, enabling the pilot to effect recovery after three-fourths of a turn in—

     “Evidence indicated that power was used in recovery from the spin in the case of NX 19901. It should be noted that in the two instances above described recovery from spin in similar aircraft was accomplished without the employment of power. In one of these cases, permanent distortion occurred in both wings.”

AIR SAFETY BOARD REPORT, at Pages 48 and 49.

Diagram of wing failure under load. (Air Safety Board Report)

PROBABLE CAUSE

     “Structural failure of the wings and horizontal tail surfaces due to the imposition of loads thereon in excess of those for which they were designed, the failure occurring in an abrupt pull-out from a dive following recovery from an inadvertent spin.”

Crash site diagram. (Air Safety Board Report)
Boeing Model 307 Stratoliner NX19901. The engine cowlings have been removed. The inboard right engine is running. The arrangement of passenger windows differs on the right and left side of the fuselage. (San Diego Air & Space Museum Archives)

The Boeing Model 307 was operated by a crew of five and could carry up to 33 passengers.  It was the first pressurized airliner and, because of its complexity, it was also the first airplane to include a flight engineer as a crew member. It could maintain a cabin pressure equivalent to 12,000 feet (3,650 meters) to a pressure altitude of 19,000 feet (5,791 meters).

The Model 307 used the wings, tail surfaces, engines and landing gear of the production B-17B Flying Fortress heavy bomber. The vertical fin and rudder were of the same design as the B-17B’s, though somewhat larger. The fuselage was circular in cross section to allow for pressurization. It was 74 feet, 4 inches (22.657 meters) long with a wingspan of 107 feet, 3 inches (32.690 meters) and overall height of 20 feet, 9½ inches (6.337 meters). The wings had 4½° dihedral and 3½° angle of incidence. The empty weight was 29,900 pounds (13,562.4 kilograms) and loaded weight was 45,000 pounds (20,411.7 kilograms).

The airliner was powered by four air-cooled, geared and supercharged, 1,823.129-cubic-inch-displacement (29.875 liter) Wright Cyclone 9 GR-1820-G102 9-cylinder radial engines with a compression ratio of 6.7:1, rated at 900 horsepower at 2,200 r.p.m., and 1,100 horsepower at 2,200 r.p.m. for takeoff. These drove three-bladed Hamilton-Standard Hydromatic propellers through a 0.6875:1 gear reduction in order to match the engine’s effective power range with the propellers. The GR-1820-G102 was 4 feet, 0.12 inches (1.222 meters) long, 4 feet, 7.10 inches (1.400 meters) in diameter, and weighed 1,275 pounds (578 kilograms).

The maximum speed of the Model 307 was 241 miles per hour (388 kilometers per hour) at 6,000 feet (1,828.8 meters). Cruise speed was 215 miles per hour (346 kilometers per hour) at 10,000 feet (3,048 meters). The service ceiling was 23,300 feet (7,101.8 meters).

Boeing Model 307 Stratoliner NX19901 with all engines running. (San Diego Air & Space Museum Archives)

Julius Augustus Barr was born at Normal, Illinois, 6 December 1905. He was the son of Oren Augustus Barr, a teacher and school superintendent, and Margaret M. Wallace Barr. He grew up in Pittsburg, Kansas. He attended the Kansas State Teachers College at Pittsburg in 1925. He was a member of the Alpha Gamma Tau (ΑΓΤ) fraternity, of which he was the treasurer.

Julius Augustus Barr

Barr enlisted in the Air Corps, United States Army, and was trained as a pilot at Brooks and Kelly Fields, San Antonio, Texas.

On 1 July 1928, Julius Barr married Miss Effie Hortense Roberson at Pittsburg, Kansas. They would have two children, Jo Anne Barr, and Gene Edward Barr.

In 1930, Barr and his family lived in Cheyenne, Wyoming. He flew as an air mail pilot, and was employed by Boeing Air Transport.

During the mid 1930s, the Barr family traveled to China, where he acted as manager of the airport at Hankow, and conducted flight training. He then flew as the personal pilot of Zhang Xueliang (also known as Chang Hseuh-Liang), (“The Young Marshal”). Zhang and another of other communist generals arrested Chiang Kai-Shek in the Xi’an Incident, December 1936. Chiang was released after two weeks, and Zhang placed under house arrest for the remainder of his life. (The others were executed.) Julius Barr then served as the personal pilot for Soong Mei-ling (“Madame Chiang”), and helped General Chang with the air defense of Shanghai during the Second Sino-Japanese War.

Barr and his family departed Hong Kong aboard S.S. Empress of Russia, which arrived at Victoria, British Columbia, Canada, 14 November 1938. He then went to work as a test pilot for Boeing two days later.

Julius Barr had flown a total of approximately 5,000 hours. Of these, 2,030 hours were in single-engine airplanes, 2,240 hours in twin-engine, and 765 hours in 3 engine.

Julius Augustus Barr was buried at the Mount Olive Cemetery, Pittsburg, Kansas.

© 2019, Bryan R. Swopes

Facebooktwittergoogle_plusredditpinterestlinkedinmailby feather

10 January 1964

Boeing B-52H-170-BW 61-023
Boeing B-52H-170-BW Stratofortress 61-023. (U.S. Air Force)

10 January 1964: This Boeing B-52H Stratofortress, serial number 61-023, flown by Boeing test pilot Charles F. (“Chuck”) Fisher, was conducting structural testing in turbulence near East Spanish Peak, Colorado. The other crew members were pilots Richard V. Curry and Leo Coer, and navigator James Pittman. Dick Curry was flying the airplane and Chuck Fisher, the aircraft commander, was in the co-pilot’s position. Pittman was on the lower deck.

The bomber was carrying two North American Aviation GAM-77 Hound Dog cruise missiles on pylons under its wings.

The Boeing B-52 Stratofortress had been designed as a very high altitude penetration bomber, but changes in Soviet defensive systems led the Strategic Air Command to change to very low altitude flight as a means of evading radar. This was subjecting the airframes to unexpected stresses. “Ten-Twenty-Three” (its serial number was 61-023, shortened on the vertical fin to “1023”) had been returned to Boeing Wichita by the Air Force to be instrumented to investigate the effects of high-speed, low-altitude flight on the 245-ton bomber.

Flying at 14,300 feet (4,359 meters) and 345 knots (397 miles per hour, 639 kilometers per hour), indicated air speed, the airplane encountered severe clear air turbulence and lost the vertical stabilizer. Several B-52s had been lost under similar circumstances. (Another, a B-52D, was lost just three days later at Savage Mountain, Maryland.)

East Spanish Peak (left), 12,688 feet (3,867 meters) and West Spanish Peak, 13,626 feet (4,153 meters), Sangre de Cristo Mountains, Colorado. (Footwarrior)
East Spanish Peak (left), 12,688 feet (3,867 meters) and West Spanish Peak, 13,626 feet (4,153 meters), Sangre de Cristo Mountains, Colorado. (Footwarrior)
Charles F. Fisher. (Argenta Images)
Charles F. Fisher. (Argenta Images)

Chuck Fisher immediately took control of the B-52. He later reported,

“As the encounter progressed, a very sharp-edged blow which was followed by many more. We developed an almost instantaneous rate of roll at fairly high rate. The roll was to the far left and the nose was swinging up and to the right at a rapid rate. During the second portion of the encounter, the airplane motions actually seemed to be negating my control inputs. I had the rudder to the firewall, the column in my lap, and full wheel, and I wasn’t having any luck righting the airplane. In the short period after the turbulence I gave the order to prepare to abandon the airplane because I didn’t think we were going to keep it together.”

A Boeing report on the incident, based on installed sensors and instrumentation aboard -023, said that the bomber had

“. . . flown through an area containing the combined effects of a (wind) rotor associated with a mountain wave and lateral shear due to airflow around a mountain peak. . . Gust initially built up from the right to a maximum of about 45 feet per second [13.7 meters per second] (TAS), then reversed to a maximum of 36 feet per second [11 meters per second] from the left, before swinging to a maximum of about 147 feet per second [44.8 meters per second] from the left followed by a return to 31 feet per second [9.5 meters per second].”

Fisher flew the bomber back to Wichita and was met by a F-100 Super Sabre chase plane. When the extent of the damage was seen, the B-52 was diverted due to the gusty winds in Kansas. Six hours after the damage occurred, Chuck Fisher safely landed the airplane at Eaker Air Force Base, Blythville, Arkansas. He said it was, “the finest airplane I’ve ever flown.”

Boeing B-52H-170-BW Stratofortress 61-023, "Ten-Twenty-Three", after losing the vertical fin, 10 January 1964. (Boeing)
Boeing B-52H-170-BW Stratofortress 61-023, “Ten-Twenty-Three”, after losing the vertical fin, 10 January 1964. (Boeing)

61-023 was repaired and returned to service. It remained active with the United States Air Force until it was placed in storage at Tinker Air Force Base, Oklahoma, 24 July 2008.

Charles F. Fisher and the Boeing test crew with B-52H Stratofortress 61-023. (Boeing)
Charles F. Fisher at left,  and the Boeing test crew with B-52H Stratofortress 61-023. (Boeing)

The B-52H is a sub-sonic, swept wing, long-range strategic bomber. It has a crew of five. The airplane is 159 feet, 4 inches (48.6 meters) long, with a wing span of 185 feet (56.4 meters). It is 40 feet, 8 inches (12.4 meters) high to the top of the vertical fin. Maximum Takeoff Weight (MTOW) is 488,000 pounds (221,353 kilograms).

There are eight Pratt & Whitney TF33-PW-3 turbofan engines mounted in two-engine pods suspended under the wings on four pylons. Each engine produces a maximum of 17,000 pounds of thrust (75.620 kilonewtons). The TF-33 is a two-spool axial-flow turbofan engine with 2 fan stages, 14-stage compressor stages (7 stage intermediate pressure, 7 stage high-pressure) and and 4-stage turbine (1 stage high-pressure, 3-stage low-pressure). The engine is 11 feet, 10 inches (3.607 meters) long, 4 feet, 5.0 inches (1.346 meters) in diameter and weighs 3,900 pounds (15,377 kilograms).

The B-52H can carry approximately 70,000 pounds (31,750 kilograms) of ordnance, including free-fall bombs, precision-guided bombs, thermonuclear bombs and cruise missiles, naval mines and anti-ship missiles.

The bomber’s cruise speed is 520 miles per hour (837 kilometers per hour) and its maximum speed is 650 miles per hour (1,046 kilometers per hour) at 23,800 feet (7,254 meters) at a combat weight of 306,350 pounds. Its service ceiling is 47,700 feet (14,539 meters) at the same combat weight. The unrefueled range is 8,000 miles (12,875 kilometers).

With inflight refueling, the Stratofortress’s range is limited only by the endurance of its five-man crew.

The B-52H is the only version still in service. 102 were built and as of 27 September 2016, 76 are still in service. Beginning in 2013, the Air Force began a fleet-wide technological upgrade for the B-52H, including a digital avionics and communications system, as well as an internal weapons bay upgrade. The bomber is expected to remain in service until 2040.

Boeing B-52H-170-BW Stratofortress 61-023 taxiing at Minot Air Force Base, North Dakota. (Senior Airman Cassandra Jones, U.S. Air Force)
Boeing B-52H-170-BW Stratofortress 61-023 taxiing at Minot Air Force Base, North Dakota. (Senior Airman Cassandra Jones, U.S. Air Force)

© 2016, Bryan R. Swopes

Facebooktwittergoogle_plusredditpinterestlinkedinmailby feather

22 December 1945

Beechcraft Model 35 Bonanza NX80040. This is the fourth prototype. It is in the collection of the Smithsonian Institution National Air and Space Museum. (Beech Aircraft Corporation)
Beechcraft Model 35 Bonanza NX80040, serial number 4. This is the fourth prototype. It is in the collection of the Smithsonian Institution National Air and Space Museum. (Beech Aircraft Corporation via Larry Westin)

22 December 1945: Test pilot Vern Louis Carstens made the first flight of Beech Aircraft Corporation’s new Beechcraft Model 35 Bonanza. Five prototypes were built. The first two were used as static test articles. The third prototype, NX80150, serial number 3, was the first to fly.

“. . . Wichita residents and Beech employees “lined the runway” to watch the first flight of the Beechcraft Bonanza. “The town turned out and the plant all but shut down for the occasion,” said Vern L. Carstens, retired Beech Aircraft chief test pilot who made the historic flight. From the day of its first flight, the Beechcraft V-tailed Bonanza has set industry standards for high performance single engine aircraft. The Bonanza received its type certificate on March 25, 1947. . . .”

The Salina Journal, Salina, Kansas, Sunday, 27 December 1970, at Page 25, Columns 1–7.

In January 1946, one of the Model 35 prototypes, possibly s/n 3, was destroyed:

“During a dive test to determine the maximum dive velocity, a landing gear door buckled under the air loads, causing the door to be forced open. Air was then forced into the landing gear recess on the underside of the wing, and internal pressure built up to the point where the wing failed.”

Department of Transportation, Transportation Systems Center Beech V-Tail Bonanza Task Force Report, 1985. [Note: The date of the accident and the name of the pilot have not been determined as yet. —TDiA]

The registration for NX80150 was cancelled 18 May 1948.

The Beechcraft Model 35 Bonanza is a single-engine, four-place all-metal light civil airplane with retractable landing gear. The Bonanza has the distinctive V-tail with a 30° dihedral which combined the functions of a conventional vertical fin and rudder, and horizontal tail plane and elevators.

The Model 35 was 25 feet, 2 inches (7.671 meters) long with a wingspan of 32 feet, 10 inches (10.008 meters) and height of 6 feet, 6½ inches (1.994 meters). It had an empty weight of 1,458 pounds (661 kilograms) and gross weight of 2,550 pounds (1,157 kilograms.)

An early production Beechcraft Model 35 Bonanza, NC2703V, c/n D-79. (Beech Aircraft Corporation via Larry Westin)
An early production Beechcraft Model 35 Bonanza, NC2703V, c/n D-79. (Beech Aircraft Corporation via Larry Westin)

The first flyable prototype, NX80150, was equipped with an air-cooled, normally aspirated 289.31-cubic-inch-displacement (4.741 liter) Lycoming O-290-A horizontally-opposed 4-cylinder engine, rated at 125 horsepower at 2,600 r.p.m., and 130 horsepower at 2,800 r.p.m (five minute limit).

Prototype number four, s/n 4, NX80040, and the following production models used a more powerful air-cooled, 471.24-cubic-inch-displacement (7.72 liter) Continental Motors, Inc., E185 horizontally-opposed 6-cylinder engine. This engine was rated at 165 horsepower at 2,050 r.p.m. The Bonanza used a two-bladed electrically-controlled variable-pitch R-100 propeller with a diameter of 7 feet, 4 inches (2.235 meters), made of laminated wood.

The “V-tail Bonanza” had a maximum speed of 184 miles per hour (296 kilometers per hour) at Sea Level, and a cruise speed of 175 miles per hour (282 kilometers per hour) at 10,000 feet (3,048 meters). Its service ceiling was 18,000 feet (5,486 meters). With full fuel, 40 gallons (151.4 liters), the airplane had a range of 750 miles (1,207 kilometers).

The Beechcraft 35 was in production from 1947 to 1982. More than 17,000 Model 35s and the similar Model 36 were built.

Beechcraft Model 35 Bonanza NX80040. (Hans Groenhoff Photographic Collection, Smithsonian Institution National Air and Space Museum NASM-HGC-201)

© 2018, Bryan R. Swopes

Facebooktwittergoogle_plusredditpinterestlinkedinmailby feather

7 December 1936

Boeing YB-17 36-149 nosed over on landing at Seattle, 7 December 1936. (Unattributed)
Boeing YB-17 36-149 nosed over on landing at Seattle, 7 December 1936. (Unattributed)
Lieutenant Colonel Stanley Umstead
Lieutenant Colonel Stanley Umstead

7 December 1936: After its third test flight, the first YB-17 service test aircraft, 36-149, landed back at Boeing Field, Seattle, Washington. The pilot was Lieutenant Colonel Stanley M. Umstead, Air Corps, United States Army, who was considered to be the Army’s most experienced and capable pilot.

When the airplane touched down, the main wheels locked and after skidding a short distance, the B-17 nosed over. The bomber’s brakes had welded. No injuries were reported. 36-149 suffered moderate damage.

Boeing repaired the bomber. On 11 January 1937, the YB-17 was  flown to Wright Field, Dayton, Ohio, for continued testing. 36-149 was then assigned to the 2nd Bombardment Group at Langley Field, Virginia, 1 March 1937. In October 1940 the bomber was transferred to the 19th Bombardment Group at March Field, California. On 11 February 1942 it was transferred to the Air Park at Amarillo Army Air Field, a B-17 training base in Texas. 36-149 was written off 11 December 1942.

A contemporary newspaper article reported the incident:

Landing from a test flight in Seattle, Wash., the new 16 ton army bombing plane YB-17 nosed over and was badly damaged. Capt. E.R. McReynolds, an army air corps observer who was aboard, said the air brakes locked, preventing the landing wheels from rolling when the plane touched the ground. It was reported subsequently in Washington, D.C. that the accident might result in suspending construction of 13 bombing planes of similar type pending an investigation. The YB-17, largest land plane ever built in America, was designed to carry a ton of bombs and had a cruising range of 3,000 miles.

Chicago Sunday Tribune, 13 December 1936, Part 2, Page 8, Column 8.

Boeing YB-17 resting on its nose after brakes locked while landing. —LIFE Magazine, 21 December 1935, at page 15
Boeing YB-17 36-149 resting on its nose after its brakes locked while landing. —LIFE Magazine, 21 December 1936, at page 15.

The YB-17 had several improvements over the Model 299, which had been retroactively designated XB-17. There were long carburetor intakes on the top of the engine nacelles, which visually distinguishes the YB-17 from the follow-on YB-17A. The main landing gear has one strut rather than the two of the Model 299.

The Boeing Model 299B was designated YB-17 by the Army Air Corps. It was 68 feet, 4 inches (20.828 meters) long with a wingspan of 103 feet, 9 inches (31.633 meters) and an overall height of 18 feet, 4 inches (5.588 meters). It had an empty weight of 24,465 pounds (11,097 kilograms), gross weight of 34,880 pounds (15,821 kilograms) and maximum takeoff weight of 42,600 pounds (19,323 kilograms).

Instead of the Pratt & Whitney engines installed on the 299, the YB-17 had four air-cooled, supercharged 1,823.129-cubic-inch-displacement (29.875 liter) Wright Aeronautical Division Cyclone 9 R-1820G5 (R-1820-39) nine-cylinder radial engines with a compression ratio of 6.45:1. The R-1820-39 was rated at 805 horsepower at 2,100 r.p.m., at Sea Level, and 930 horsepower at 2,200 r.p.m., at Sea Level, for takeoff. The engines turned three-bladed Hamilton Standard constant-speed propellers through a 16:11 gear reduction, in order to match the engines’ effective power range with the propellers. The R-1820-39 was 3 feet, 9-7/16 inches (1.154 meters) long, 4 feet, 6-¼ inches (1.378 meters) in diameter, and weighed 1,198 pounds (543.4 kilograms).

The cruise speed of the YB-17 was 217 miles per hour (349 kilometers per hour) and its maximum speed was 256 miles per hour (412 kilometers per hour) at 14,000 feet (4,267 meters). The bomber’s service ceiling was 30,600 feet (9,327 meters) and the maximum range was 3,320 miles (5,343 kilometers).

The YB-17 could carry 8,000 pounds (3,629 kilograms) of bombs. Defensive armament consisted of five .30-caliber air-cooled machine guns.

Boeing YB-17 36-139 after landing accident, 7 December 1936.
Boeing YB-17 36-149 after landing accident, 7 December 1936. (Unattributed)

© 2018, Bryan R. Swopes

Facebooktwittergoogle_plusredditpinterestlinkedinmailby feather