Tag Archives: Bomber

9 January 1941

BT308, the Avro Lancaster prototype, at RAF Ringway, 9 January 1941. (Avro Heritage Museum)
Captain Harry Albert (“Sam”) Brown, O.B.E. (Photograph courtesy of Neil Corbett, Test & Research Pilots, Flight Test Engineers)

9 January 1941: Test pilot Captain Harry Albert (“Sam”) Brown, O.B.E., (1896–1953) makes the first flight of the Avro Lancaster prototype, BT308, at RAF Ringway, Cheshire, England, south of Manchester.

Throughout World War II, 7,377 of these long range heavy bombers were produced for the Royal Air Force. The majority were powered by Rolls-Royce or Packard Merlin V-12 engines—the same engines that powered the Supermarine Spitfire and North American P-51 Mustang fighters.

The bomber was designed by Roy Chadwick, F.R.S.A., F.R.Ae.S., the Chief Designer and Engineer of A. V. Roe & Company Limited, based on the earlier twin-engine Avro Manchester Mk.I. Because of this, it was originally designated as the Manchester Mk.III, before being re-named Lancaster. Chadwick was appointed Commander of the Most Excellent Order of the British Empire, 2 June 1943, for his work.

The first prototype, BT308, was unarmed and had three small vertical fins.

Avro 683 Lancaster prototype BT308, shortly after the first flight at Manchester, 9 January 1941. (A.V.Roe via R.A.Scholefield) Photograph used with permission.
Avro 683 Lancaster prototype BT308, shortly after the first flight at RAF Ringway, Manchester, England, 9 January 1941. (A.V.Roe via R.A.Scholefield) Photograph is from The R.A. Scholefield Collection and is used with permission.

With the second prototype, DG595, the small center vertical fin was deleted and two larger fins were used at the outboard ends of a longer horizontal tailplane. DG595 was also equipped with power gun turrets at the nose, dorsal and ventral positions, and at the tail.

Avro Lancaster DG595, the second protoype of the Royal Air Force four-engine heavy bomber. This armed prototype has the twin-tail arrangement of the production aircraft. (Unattributed)
Avro Lancaster DG595, the second protoype of the Royal Air Force four-engine long range heavy bomber. This armed prototype has the twin-tail arrangement of the production aircraft. (Test & Research Pilots, Flight Test Engineers)
Air Ministry clearance form for Avro 638 Lancaster BT308. Shown on page 1 are the aircraft's engine type and serial numbers.
Air Ministry clearance form for Avro 683 Lancaster BT308. Shown on page 1 are the aircraft’s engine type and serial numbers.
Air Ministry test flight clearance form, Page 2.
Air Ministry test flight clearance form, Page 2. This form is signed by the airplane’s designer, Roy Chadwick, 5 January 1941.

The first production model, Lancaster Mk.I, was operated by a crew of seven: pilot, flight engineer, navigator/bombardier, radio operator and three gunners. It was a large, all-metal, mid-wing monoplane with retractable landing gear. It was 68 feet, 11 inches (21.001 meters) long with a wingspan of 102 feet, 0 inches (31.090) meters and an overall height of 19 feet, 6 inches (5.944 meters). The Mk.I had an empty weight of 36,900 pounds (16,738 kilograms) and its maximum takeoff weight was 68,000 pounds (30,909 kilograms).

BT308 and early production Lancasters were equipped with four liquid-cooled, supercharged, 1,648.96-cubic-inch-displacement (27.01 liter), Roll-Royce Merlin XX single overhead camshaft (SOHC) 60° V-12 engines, which were rated at 1,480 horsepower at 3,000 r.p.m. to 6,000 feet (1,829 meters). The Merlins drove three-bladed de Havilland Hydromatic quick-feathering, constant-speed airscrews (propellers), which had a diameter of 13 feet, 0 inches (3.962 meters), through a 0.420:1 gear reduction.

DG595 was used for performance testing at the Aeroplane and Armament Experimental Establishment (A&AEE) at Boscombe Down. The Mark I had a maximum economic cruise speed of 267 miles per hour (430 kilometers per hour) at 20,800 feet (6,340 meters), and a maximum speed of 286 miles per hour (460 kilometers per hour) at 20,000 feet (6,096 meters) at a gross weight of 45,300 pounds (20,548 kilograms).¹ Its service ceiling was 20,000 feet (6,096 meters) at 64,500 pounds (29,257 kilograms). It had a range of  2,530 miles (4,072 kilometers) with a 7,000 pound (3,175 kilogram) bomb load.

The Lancaster was designed to carry a 14,000 pound (6,350 kilogram) bomb load, but modified bombers carried the 22,000 pound (9,979 kilogram) Grand Slam bomb. For defense, the standard Lancaster had eight Browning .303-caliber Mark II machine guns in three power-operated turrets, with a total of 14,000 rounds of ammunition.

According to the Royal Air Force, “Almost half all Lancasters delivered during the war (3,345 of 7,373) were lost on operations with the loss of over 21,000 crew members.”

Only two airworthy Avro Lancasters are in existence.

The Royal Air Force Battle of Britain Memorial Flight Avro Lancaster Mk.I, PA474. This airplane was built in 1945 by Vickers Armstongs Ltd. at Broughton, Wales, United Kingdom. (Battle of Britain Memorial Flight)
The Canadian Warplane Heritage Museum’s Avro Lancaster Mk.X FM213, flies formation with an Royal Canadian Air Force CF-188 Hornet. The bomber is marked VR A and nicknamed “Vera.” FM213 was built by Victory Aircraft Ltd., Malton, Ontario, Canada. (Canadian Warplane Heritage Museum)

¹ Speeds shown are True Air Speed (T.A.S.)

© 2019, Bryan R. Swopes

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17 December 1947

Boeing XB-47 Stratojet 46-065 in flight over a snow-covered landscape. (U.S. Air Force)
Boeing XB-47 Stratojet 46-065 in flight over a snow-covered landscape. (U.S. Air Force)
Robert M. Robbins
Robert M. Robbins

17 December 1947: Boeing test pilots Robert M. Robbins and Edward Scott Osler made the first flight of the Model 450, the XB-47 Stratojet prototype. It was a 52-minute flight from Boeing Field, Seattle to Moses Lake, Washington.

Robbins later said, “The best way to tell about the performance of the Stratojet is to say that any good crew could have flown it. It took no unusual ability or education. Neither Scott Osler nor I deserve any credit for the flight. Rather, the credit should go to the men who carried out these visions on the drafting boards and the factory workers who made the visions a reality.”

On 11 May 1949, during flight testing at Moses Lake, the canopy of 46-065 came off, killing test pilot Scott Osler. The co-pilot safely landed the airplane. The XB-47 stalled while landing at Moses Lake, 18 August 1951, and was damaged beyond repair.

Designed as a strategic bomber, the B-47 could fly higher and faster than jet fighters of the time, and it was also highly maneuverable. The XB-47 (Boeing Model 450) was flown by a two-man crew in a tandem cockpit. It was 107 feet, 6 inches (32.766 meters) long with a wingspan of 116 feet (35.357 meters). The top of the vertical fin was 27 feet, 8 inches (8.433 meters) high. The wings were shoulder-mounted with the leading edges swept at 35°.

Boeing XB-47 Stratojet 46-065. (U.S. Air Force)

The first prototype was powered by six General Electric J35-GE-7 axial flow turbojet engines in four pods mounted on pylons below the wings. The J35 was a single-spool, axial-flow turbojet engine with an 11-stage compressor and single-stage turbine. The J35-GE-7 was rated at 3,750 pounds of thrust (16.68 kilonewtons) (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 second prototype, 46-066, was completed with J47 engines. 46-065 was later retrofitted with these engines.)

The XB-47 had a maximum speed of 578 miles per hour (930 kilometers per hour) at 15,000 feet (4,572 meters). The prototype’s maximum takeoff weight was 162,500 pounds (73,708.8 kilograms). The service ceiling was 37,500 feet (11,430 meters). The estimated range was 2,650 miles (4,265 kilometers) with a 10,000 pound (4,535.9 kilogram) bomb load.

Boeing XB-47 Stratojet 46-065, the first of two prototypes, on the ramp at Boeing Field, Seattle, 1 December 1947. (U.S. Air Force)
Boeing XB-47 Stratojet 46-065, the first of two prototypes, on the ramp at Boeing Field, Seattle, 1 December 1947. (U.S. Air Force)

The Stratojet was one of the most influential aircraft designs of all time and its legacy can be seen in almost every jet airliner built since the 1950s: The swept wing with engines suspended on pylons.

2,032 B-47s were built by Boeing Wichita, Douglas Tulsa and Lockheed Marietta. They served the United States Air Force from 1951 to 1977.

Right rear quarter view of Boeing XB-47 Stratojet 46-065. (U.S. Air Force)
Right rear quarter view of Boeing XB-47 Stratojet 46-065. (U.S. Air Force)

The very last B-47 flight took place 18 June 1986 when B-47E-25-DT, serial number 52-166, was flown from the Naval Air Weapons Center China Lake to Castle Air Force Base to be placed on static display.

Boeing XB-47 Stratojet 46-065. (U.S. Air Force)
Boeing XB-47 Stratojet 46-065. (U.S. Air Force)

The second prototype, XB-47 46-066, is in the collection of the Air Force Flight Test Museum, Edwards Air Force Base, California.

Boeing XB-47 Stratojet 46-066, Sandia. (SDASM)

© 2017, Bryan R. Swopes

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13 December 1918

Handley Page V/1500. (Royal Air Force)
Handley Page V/1500. (Royal Air Force)
Archibald Charles Stuart MacLaren.
Archibald Stuart Charles Stuart-MacLaren, Squadron Leader, Royal Air Force.

13 December 1918: Major Archibald Stuart Charles Stuart-MacLaren, Captain Robert (“Jock”) Halley, D.F.C., A.F.C., accompanied by Brigadier General Norman D.K. MacEwan (later, Air Vice Marshal Sir Norman Duckworth Kerr MacEwen C.B., C.M.G., D.S.O., R.A.F.), who would be the new Air Officer Commanding in India, left Martlesham Heath, Woodbridge, Suffolk, England, for India aboard a Handley Page V/1500 heavy bomber, J1936, HMA Old Carthusian. Also aboard were Flight Sergeant Smith and Sergeant Crockett, fitters, and Sergeant Thomas Brown, rigger.

N.D.K. MacEwan, Lieutenant Colonel, Royal Air Force
N.D.K. MacEwan, Lieutenant Colonel, Royal Air Force

The route of flight was Rome, Malta, Cairo, Baghdad, and finally, Karachi. They would arrive on 15 January 1919.

2nd Air Mechanic Archibald Stuart Charles Stuart-MacLaren was issued Aviator’s Certificate No. 1310 by The Royal Aero Club of the United Kingdom, 4 June 1915. He trained in a Caudron Biplane at the British Flying School, Le Crotoy, France.

Group Captain Robert Halley, R.A.F., had been a cyclist with the Royal Highlanders. He requested flight training and was accepted as a probationary Flight Officer. He was trained at RNAS Vendome. During World War I, Halley flew more than twenty long range night bombing missions over Germany, for which he was awarded two Distinguished Flying Crosses.

On 24 May 1919, during the Third Afghan War, Halley flew Old Carthusian through the Khyber Pass in pre-dawn darkness with observer Lieutenant Ted Villiers and the three sergeants, Smith, Crockett and Brown.

The Handley Page V/1500 was armed with a bomb load of four 112 pound (50.8 kilogram) and sixteen 20 pound (9.1 kilogram) bombs. The target was the royal palace of Amanullah Khan in Kabul. The bombs were released from an altitude of 700 feet (213 meters) and did little damage, but with the resulting panic, the Khan surrendered. The single bombing raid is credited with ending the war.

Cockpit of a Handley Page V/1500.
Cockpit of a Handley Page V/1500.

The Handley Page V/1500 first flew 22 May 1918. The designation comes from the original name, Type 5, combined with the total horsepower of its engines. It was a three-bay biplane with four engines mounted in two nacelles between the upper and lower wings. The bomber was 64 feet, 0 inches (19.507 meters) long with a wingspan of 126 feet, 0 inches (38.405 meters) and was 23 feet, 0 inches (7.010 meters) high. Empty weight was 17,600 pounds (7,983 kilograms) and maximum takeoff weight was 30,000 pounds (13,608 kilograms).

The engines were water-cooled, normally-aspirated, 1,240.536-cubic-inch-displacement (20.329 liter) Rolls-Royce Eagle VIII single overhead cam (SOHC) 60° V-12s, each rated at 360 horsepower at 1,800 r.p.m. Maximum engine speed was 1,900 r.p.m. The Eagle VIII had a propeller gear reduction ratio of 0.6:1. Two of the engines were at the forward end of the nacelles in tractor configuration, and two were at the rear in pusher configuration. The propellers were two-bladed units with fixed pitch.

Rolls-Royce Eagle VIII aircraft engine (serial number 5272) at the Smithsonian Institution National Air and Space Museum. (NASM)

The V/1500 had a maximum speed of 99 miles per hour (159.3 kilometers per hour) at Sea Level, and its service ceiling was 11,000 feet (3,353 meters). It carried fuel to remain airborne for 17 hours. Maximum range was 1,300 miles (2,092 kilometers).

The V/1500 was armed with three .303-caliber Lewis machine guns. The maximum bomb load was 7,500 pounds (3,402 kilograms).

Handley Page built 63 V/1500 bombers. J1936, being constructed primarily of wood and fabric, finally succumbed to termites.

Handley Page V/1500 (Bain News Service/Library of Congress)
Handley Page V/1500. (Bain News Service/Library of Congress)
Handley Page V/1500 with wings folded. (Royal Air Force)
Handle Page V/1500 (Bain New Service/Library of Congress)

© 2017, Bryan R. Swopes

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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

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2 December 1936

Boeing YB-17 Flying Fortress 36-149. (U.S. Air Force)
Boeing YB-17 Flying Fortress 36-149. (U.S. Air Force)

2 December 1936: The first Boeing YB-17, U.S. Army Air Corps serial number 36-149, made its first flight.

Although the prototype Boeing Model 299, NX13372, had crashed at Wright Field, Ohio, 30 October 1935, the Army had ordered thirteen Y1B-17 service test aircraft, serials 36-149–36-161. Prior to the model’s first flight, this designation was changed to YB-17. (The “-1-” in the original Y1B-17 designation indicated that the service test bombers were ordered using funding other than the normal appropriations for new aircraft.)

Boeing YB-17. (U.S. Air Force)
Boeing YB-17 36-149. (U.S. Air Force)

The YB-17 had several improvements over the Model 299, which was retroactively designated XB-17. There was a long carburetor intake on 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.

Boeing YB-17 36-149. (U.S. Air Force)

The Boeing Model 299B, designated YB-17 by the Army Air Corps, was 68 feet, 4 inches (20.828 meters) long with a wingspan of 103 feet, 9 inches (31.633 meters) and the overall height was 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).

Boeing YB-17 36-149. (U.S. Air Force)

Instead of the Pratt & Whitney engines installed on the 299, the YB-17 had four air-cooled, supercharged 1,823.129-cubic-inch-displacement (29.876 liter) Wright Aeronautical Division Cyclone 9 R-1820G5 (R-1820-39) nine-cylinder radial engines with a compression ratio of 6.45:1. They turned three-bladed Hamilton Standard constant-speed propellers through a 16:11 gear reduction drive, in order to match the engines’ effective power range with the propellers. 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. for takeoff. The R-1820-39 was 45-7/16 inches (1.154 meters) long and 54¼ 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 the maximum speed was 256 miles per hour (412 kilometers per hour) at 14,000 feet (4,267 meters). Its service ceiling was 30,600 feet (9,327 meters). The bomber’s 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 Browning machine guns.

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

36-149 was damaged in a landing accident 7 December 1936. It was repaired and then flown to Wright Field, Dayton, Ohio, 11 January 1937. After testing at Wright Field, 36-149 was delivered to the 2nd Bombardment Group, Langley Field, Virginia. By 1938 the bomber was back at Wright Field for additional tests.

“In the summer of 1938, Bill [Captain William C. Bentley, Jr., U.S. Army Air Corps, a B-17 test pilot at Langley Field] and his aircrew flew back to Seattle to pick up an additional aircraft, YB-17 tail number 36-149 from Boeing. This aircraft was different from the original thirteen. During its assembly phase at Boeing, it was packed with additional instruments for recording purposes. Once delivered to Langley, the plane was going to be subjected to a variety of stress tests in order to determine how much damage the plane could take and still operate. During its flight to Langley, Bill arrived over the field in a thunderstorm. The strength of the storm flipped the plane upside down, a stress never envisioned by the designers for such a large aircraft, much less one loaded to capacity with measuring instrumentation and a full crew. Using his fighter pilot training, Bill flew the aircraft at its maximum altitude then performed a slow roll to bring the airplane into its proper attitude. After recovering from a harrowing spin, Bill got control of the plane and landed successfully.

“Much to the crew’s amazement, the wings were slightly bent and some rivets were missing. But the measuring instrumentation had recorded all of the stress placed on the plane. . . .”

—The Touch of Greatness: Colonel William C. Bentley, Jr., USAAC/USAF, by Stewart W. Bentley, Jr., Ph.D., AuthorHouse, Bloomington, Indiana, 2010, Chapter 2 at Page 45.

(This meant that a fourteenth YB-17, which had been built specifically as a static test article, could be completed as a Y1B-17A, 37-369.)

Boeing YB-17 at Hamilton Field, California. (U.S. Air Force)

In October 1940 36-149 was transferred to the 19th Bombardment Group at March Field, California. Finally, on 11 February 1942, it was transferred to the Air Park at Amarillo Army Air Field, a B-17 training base in Texas. It was written off 11 December 1942.

After several years of testing, the YB-17 went into production as the B-17 Flying Fortress. By the end of World War II, 12,731 B-17s had been built by Boeing, Douglas and Lockheed Vega.

Boeing YB-17 36-139 arrives at Langley Field, Virginia, 1 March 1937. (U.S. Air Force)
Boeing YB-17 36-139 arrives at Langley Field, Virginia, 1 March 1937. (U.S. Air Force)
Boeing YB-17 36-149 at Langley Field, Virginia, 1 March 1937. (U.S. Air Force)
Boeing YB-17 36-149 at the Golden Gate International Exposition, Treasure Island, California, ca. 1939. (Stephen Fisher)

© 2018, Bryan R. Swopes

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