Tag Archives: Boeing Field

15 April 1952

April 15, 2024Aviation49-231, Alvin Melvin Johnston, Boeing Airplane Company, Boeing Field, Boeing YB-52 Stratofortress, First Flight, Guy Mannering Townsend III, Pratt & Whitney Turbo Wasp, Pratt & Whitney YJ57-P-3, Prototype, Strategic Bomber, Test Pilot, Tex JohnstonBryan Swopes

15 April 1952: At 11:08 a.m., Boeing’s Chief of Flight Test, Alvin M. “Tex” Johnston, and Lieutenant Colonel Guy M. Townsend, U.S. Air Force, ran all eight turbojet engines to full power and released the brakes on the YB-52 Stratofortress prototype, 49-231.

With an awesome eight-engine roar, the YB-52 sprang forward, accelerating rapidly, wings curving upward as they accepted the 235,000-pound initial flight gross weight. At V₂ (takeoff speed) the airplane lifted off the runway, because of the 6-degree angle of incidence of the wing, and at 11:08 a.m. we were airborne. The initial flight of the YB-52 had begun.

—Tex Johnston: Jet-Age Test Pilot, by A.M. “Tex” Johnston with Charles Barton, Smithsonian Books, Washington, D.C., 1992, Chapter 13 at Pages 397–398.

Alvin M. "Tex" Johnston, test pilot, after the first flight of the Boeing XB-52 Stratofortress prototype, 2 October 1952. (LIFE via Jet Pilot Overseas) — Alvin M. “Tex” Johnston, Boeing Chief of Flight Test, after the first flight of the Boeing XB-52 Stratofortress prototype, 2 October 1952. (LIFE via Jet Pilot Overseas)

The YB-52 remained over the Seattle area for approximately 40 minutes while Johnson and Townsend ran through a series of systems checks. When completed, they climbed to 25,000 feet (7,620 meters) and flew the new bomber to Larson Air Force Base at Moses Lake, Washington, where they stayed airborne for continued testing. The Stratofortress finally touched down after 3 hours, 8 minutes—the longest first flight in Boeing’s history up to that time. Johnston radioed that the airplane performed exactly as the engineers had predicted.

Boeing YB-52 Stratofortress 49-231. (Boeing)

The YB-52 had actually been ordered as the second of two XB-52s, but modifications and additional equipment installed during building resulted in enough differences to warrant a designation change. The first XB-52, 49-230, should have been the first to fly, but it was damaged during ground testing.

Boeing XB-52 Stratofortress 49-230. (United States Air Force 040315-F-9999G-004) — Boeing XB-52 Stratofortress 49-230. (U. S. Air Force)

The Boeing XB-52 and YB-52 were prototypes for a very long range strategic bomber. Both were built with a tandem cockpit for the pilot and co-pilot, similar to the earlier B-47 Stratojet. The wings were swept and mounted high on the fuselage (“shoulder-mounted”). The eight turbojet engines were in in two-engine nacelles mounted on pylons, below and forward of the wings. This had the effect of preventing the airplane’s center of gravity from being too far aft, and also provided cleaner air flow across the wings. The B-52’s landing gear has four main struts with two wheels, each. They can turn to allow the airplane to face directly into the wind while the landing gear remain aligned with the runway for takeoff and landing. With the landing gear under the fuselage, the wings could be constructed with greater flexibility.

Boeing YB-52 Stratofortress 49-231. (U.S. Air Force)

The YB-52 was 152 feet, 8 inches (46.533 meters) long with a wingspan of 185 feet, 0 inches (56.388 meters). The prototype’s overall height was 48 feet, 3.6 inches (14.722 meters). The vertical fin could be folded over to the right so that the B-52 could fit into a hangar. The total wing area was 4,000 square feet (371.6 square meters). The wings’ leading edges were swept aft to 36° 54′. Their angle of incidence was 6° and there was 2° 30′ dihedral. The YB-52 had an empty weight of 155,200 pounds (70,398 kilograms) and gross weight of 405,000 pounds (183,705 kilograms).

The YB-52 was powered by eight Pratt & Whitney Turbo Wasp YJ57-P-3 turbojet engines. The J57 was a two-spool, axial-flow turbojet developed from an experimental turboprop engine. It had 16-stage compressor section (9 low- and 7-high-pressure stages), 8 combustors and a 3-stage turbine section (1 high- and 2 low-pressure stages). The YJ57-P-3s had a continuous power rating of 8,700 pounds of thrust (38.70 kilonewtons). The YJ57-P-3 was 183.5 inches (4.661 meters) long, 41.0 inches (1.041 meters) in diameter and weighed 4,390 pounds (1,991 kilograms).

The YB-52 had a cruise speed of 519 miles per hour (835 kilometers per hour) and maximum speed of 611 miles per hour (983 kilometers per hour) at 20,000 feet (6,096 meters). Its range was 7,015 miles (11,290 kilometers).

The two prototypes were unarmed.

The B-52 was produced by Boeing at its plants in Seattle and Wichita from 1952 to 1962, with a total of 744 Stratofortresses built. The last version, the B-52H, entered service with the Strategic Air Command in 1960. The final B-52, B-52H-175-BW Stratofortress 61-0040, was rolled out at Wichita, Kansas, 26 October 1962. This airplane remains in service with the United States Air Force. The newest B-52 in service, 61-0040 is 62 years old and has flown more than 21,000 hours.

The Boeing YB-52 Stratofortress, 49-231, lands on Rogers Dry Lake, circa 1953. (U.S. Air Force 071204-F-9999J-039)

All previous versions, B-52A through B-52G, have long been retired to The Boneyard and scrapped. Of the 102 Boeing B-52H Stratofortress bombers, 76 are still in the active inventory. One, 61-007, known as Ghost Rider, was recently taken from Davis-Monthan and after an extensive restoration and update, returned to service.

The YB-52 prototype was retired to the National Museum of the United States Air Force in the late 1950s. By the mid-60s it was determined to be excess and was scrapped.

Captain William Magruder (standing) Boeing Chief Test Pilot Alvin M. Johnston (center) and Lieutenant Colonel Guy M. Townsend with the Boeing YB-52 Stratofortress 49-231. (Boeing) — Left to right: Captain William Magruder, USAF; Boeing Chief Test Pilot Alvin M. Johnston; and Lieutenant Colonel Guy M. Townsend, USAF, with the Boeing YB-52 Stratofortress, 49-231. (Boeing)

11 March 1957

March 11, 2024AviationAlvin Melvin Johnston, BFI, Boeing 367-80, Boeing Field, BWI, c/n 17158, Friendship National Airport, Jackee Gibson, James Russell Gannett, Jo Ann Reeber, N70700, Pratt & Whitney Turbo Wasp JT3C, Samuel Lewis Wallick Jr., Shirley Mae Adams, Tex JohnstonBryan Swopes

Pre-flight inspection at Boeing Field, Seattle, Washington. In the background are newly-built Boeing B-52 Stratofortress bombers. (Leonard Mccombe/LIFE Magazine)

Tex Johnston checks that the ramp is clear for engine start. Ready to start number one. (Leonard Mccombe/LIFE Magazine)

11 March 1957: The Boeing jet airliner prototype, the Model 367-80, N70700, made a transcontinental demonstration flight from Seattle’s Boeing Field (BFI) to Friendship National Airport (BWI), Baltimore, Maryland. The aircraft commander was Boeing’s Chief of Flight Test, Alvin Melvin (“Tex”) Johnston. Test pilots James Russell (“Jim”) Gannett and Samuel Lewis (“Lew”) Wallick, Jr., completed the flight crew. The flight covered 2,350 miles (3,782 kilometers) and took 3 hours, 48 minutes.

Cruising at 0.86 Mach. (Leonard Mccombe/LIFE Magazine) — Cruising at 0.86 Mach. The four Pratt & Whitney JT3C turbojet engines are turning 100% r.p.m. (Leonard Mccombe/LIFE Magazine)

The flight deck of the Boeing 367-80 during the transcontinental demonstration flight, 11 March 1957. (Leonard Mccombe, LIFE magazine) — The flight deck of the Boeing 367-80 during the transcontinental demonstration flight, 11 March 1957. The flight attendants are (left) Miss Shirlee Mae Adams of American Airlines, and Miss Jo Ann Reeber, Trans World Airways.(Leonard Mccombe/LIFE magazine)

Reporters balance a pen and a coin in the Dash 80's vibration-free cabin. (Leonard Mccombe/LIFE Magazine) — Reporters balance a pen and a coin in the Dash 80’s vibration-free cabin. (Leonard Mccombe/LIFE Magazine)

A news reporter types his story during the transcontinental flight. (Leonatd Mccombe/LIFE Magazine) — A news reporter types his story during the transcontinental flight. (Leonard Mccombe/LIFE Magazine)

Boeing test pilot S.L. "Lew" Wallick updates the chart with the Dash 80's present position. (Leonard Mccombe/LIFE Magazine) — Boeing test pilot Samuel Lewis (“Lew”) Wallick, Jr., updates the chart with the Dash 80’s present position. (Leonard Mccombe/LIFE Magazine)

Flight attendants from Pan American World Airways, American Airlines and Trans World Airlines made up the cabin crew. (Leonard Mccombe/LIFE Magazine) — Flight attendants from three customer airlines made up the cabin crew of the Boeing 367-80. Left to right, they are: Miss Shirlee Mae Adams, American Airlines; Miss Jackee Gibson, Braniff International Airways; and Miss Jo Ann Reeber, Trans World Airways. (Leonard Mccombe/LIFE Magazine)

Jet Airliner Crosses U.S. At Record Clip

Seattle-To-Baltimore Flight Made In 3 Hours, 48 Minutes

WASHINGTON, March 12 (AP) A Boeing 707 jet passenger plane set a new transcontinental speed record for commercial aircraft yesterday, flying the 2,325 miles from Seattle to Baltimore in 3 hours and 48 minutes.

At one point it attained a speed of 698 miles an hour.

A.M. (Tex) Johnston, Boeing chief of flight tests, said he would fly back to Seattle tomorrow with stops at Chicago’s O’Hare Airport and at Denver. He planned a series of local flights for congressmen, Pentagon officials and experts.

The big plane averaged 612 miles an hour for its Puget Sound-to-Chesapeake Bay flight, and sliced 10 minutes off the unofficial transport plane record it set between Seattle and Washington, D.C., in 1955.

There were 52 persons aboard, all but 20 of them newsmen.

‘Jet Stream’ Helps

The 707 left Boeing Field at 10:06 a.m., EST. East of Spokane at 31,000 feet, it hit the “jet stream,” a vast windstream with speeds of up to 125 miles an hour.

These winds enabled the plane to attain supersonic speeds in relation to the ground over northwestern Montana and northern Idaho. However, the plane was actually in subsonic flight and did not break the “sound barrier.”

While in the jet stream, the plane’s peak air speed was 596 miles an hour, but at one point the stream boosted this by 102 miles an hour, for a top speed of 698 in relation to the ground.

Fighter Holds Record

The official transcontinental speed record was set by a one-place F-84F jet fighter two years ago—652½ mph for the 2,446 miles from Los Angeles to New York City. [LCOL Robert R. Scott, USAF, 9 March 1955—TDiA]

The fastest unofficial transcontinental crossing listed by the Defense Department: 715 mph for the 2,700 miles from Riverside, Calif., to Boston last Jan. 25, by a Boeing B-47 bomber.

The 707 is to be delivered to its first airline buyers—Pan American and American—late next year and early in 1959.

The plane’s cost varies from 4½ to 5½ million dollars, depending on size and range, Various models will carry from 120 to 162 passengers.

—Toledo Blade, Tuesday, 12 March 1957, Page 2 at Columns 2–4

Boeing's Chief of Flight Test, Alvin M. "Tex" Johnston updates a memeber of teh cabin crew on the progress of the flight. (Leonard Mccombe/LIFE Magazine) — Boeing’s Chief of Flight Test, Alvin M. “Tex” Johnston, updates a member of the cabin crew, Miss Jackie Gibson of Braniff International Airways, on the progress of the Dash 80’s transcontinental flight. (Leonard Mccombe/LIFE Magazine)

Boeing's Chief of Flight Test guides the Dash 80 to a touchdown on Runway 10, Friendship National Airport, (Leonard Mccombe/LIFE Magazine) — Boeing’s Chief of Flight Test Alvin M. “Tex” Johnston guides the Dash 80 to touchdown on Runway 10, Friendship National Airport, 2:02 p.m., Eastern Standard Time, 11 March 1957. (Leonard Mccombe/LIFE Magazine)

Tex Johnston with flight attendants from Boeing's customers: Pan American World Airways, American Airlines and Trans World Airways. (Leonard Mccombe/LIFE Magazine) — Tex Johnston with three flight attendants from Boeing’s customers: Miss Jackie Gibson, Braniff International Airways; Miss Shirlee Mae Adams, American Airlines; and Miss Jo Ann Reeber, Trans World Airways. (Leonard Mccombe/LIFE Magazine)

Boeing 367-80 N70700 parked at teh international terminal, Friendship National Airport, Baltimore, Maryland. (Leonard Mccombe/LIFE Magazine) — Boeing 367-80 N70700 parked at the international terminal, Friendship National Airport, Baltimore, Maryland. (Leonard Mccombe/LIFE Magazine)

N70700's route of flight, 0706–1102, 11 March 1957. (Leonard Mccombe/LIFE Magazine) — N70700’s route of flight, 0706–1102, 11 March 1957. (Leonard Mccombe/LIFE Magazine)

Boeing had risked $16,000,000 in a private venture to build the Dash 80 in order to demonstrate its capabilities to potential civilian and military customers, while rivals Douglas and Lockheed were marketing their own un-built jet airliners. Put into production as the U.S. Air Force KC-135A Stratotanker air refueling tanker and C-135 Stratolifter transport, a civil variant was also produced as the Boeing 707 Stratoliner, the first successful jet airliner. Though they look very similar, the 707 is structurally different than the KC-135 and has a wider fuselage.

The prototype Boeing Model 367-80 was operated by a pilot, co-pilot and flight engineer. The airplane’s wing was mounted low on the fuselage and the engine nacelles were mounted on pylons under the wing, as they were on Boeing’s B-47 Stratojet and B-52 Stratofortress. The wings and tail surfaces were swept to 35° at 25% chord, and had 7° dihedral. The Dash 80 was 127 feet 10 inches (38.964 meters) long with a wingspan of 129 feet, 8 inches (39.522 meters) and overall height of 38 feet (11.582 meters). The tail span is 39 feet, 8 inches (12.090 meters). The empty weight of the 367-80 was 75,630 pounds (34,505 kilograms) and the gross weight, 190,000 pounds (86,183 kilograms).

Boeing 367-80 cutaway scale model showing the interior arrangement. (Boeing) — Cutaway scale model of the Boeing 367-80 showing interior arrangement. (Boeing)

N70700 was powered by four Pratt & Whitney Turbo Wasp JT3C engines. This engine is a civil variant of the military J57 series. It is a two-spool, axial-flow turbojet engine with a 16-stage compressor and 2-stage turbine. The JT3C-6 (used in the first production 707s) was rated at 11,200 pounds of thrust (49.82 kilonewtons), and 13,500 pounds (60.05 kilonewtons) with water/methanol injection). The JT3C is 11 feet, 6.6 inches (3.520 meters) long, 3 feet, 2.9 inches (0.988 meters) in diameter, and weighs 4,235 pounds (1,921 kilograms).

These gave the 367-80 a cruise speed of 550 miles per hour (885 kilometers per hour) and a maximum speed of 0.84 Mach (582 miles per hour, 937 kilometers per hour) at 25,000 feet (7,620 meters). The service ceiling was 43,000 feet (13,106 meters). Its range was 3,530 miles (5,681 kilometers).

Boeing continued to use the 367–80 for testing, finally retiring it 22 January 1970. At that time, its logbook showed 2,346 hours, 46 minutes of flight time (TTAF). It was flown to Davis-Monthan Air Force Base, Tucson, Arizona, and placed in storage. In 1990, Boeing returned it to flyable condition and flew it back it to Renton where a total restoration was completed. Many of those who had worked on the Dash 80, including Tex Johnston, were aboard.

The pioneering airplane was presented to the Smithsonian Institution and is on display at the National Air and Space Museum, Steven V. Udvar-Hazy Center. The Boeing 367-80 was designated an International Historic Mechanical Engineering Landmark by the American Society of Mechanical Engineers.

(The Boeing Model 367-80 is on display at the Steven F. Udvar-Hazy center, Smithsonian Institution National Air and Space Museum. (Photo by Dane Penland, National Air and Space Museum, Smithsonian Institution) — The Boeing Model 367-80 is on display at the Steven F. Udvar-Hazy Center, Smithsonian Institution National Air and Space Museum. (Photo by Dane Penland, National Air and Space Museum, Smithsonian Institution)

Highly recommended: Tex Johnston, Jet-Age Test Pilot, by A.M. “Tex” Johnston with Charles Barton, Smithsonian Books, Washington, D.C., 1991

18 February 1943, 12:26 p.m., Pacific War Time

February 18, 2024Aviation1, 41-0003, 42-24579, Aircraft Accident, B-29-40-BW, Boeing Aircraft Company, Boeing B-29 Superfortress, Boeing Field, Boeing XB-29, Eddie Allen, Edmund Turney Allen, Frye Meat Packing Plant, PrototypeBryan Swopes

The second prototype Boeing XB-29 Superfortress, 41-0003, takes off from Boeing Field, 12:09 p.m., 18 February 1943. (Boeing)

18 February 1943: At 12:09 p.m., Boeing Aircraft Company Chief Test Pilot Edmund Turney (“Eddie”) Allen took off from Boeing Field, Seattle, Washington, in the Number 2 prototype XB-29 Superfortress long-range heavy bomber, serial number 41-0003. Allen’s co-pilot was engineering test pilot Robert R. Dansfield. The rest of the XB-29 flight crew were Charles Edmund Blaine, flight test engineer; Fritz Mohn, senior inspector; Vincent W. North, aerodynamicist; Harry William Ralston, radio operator; Barclay J. Henshaw, flight test analyst; Thomas R. Lankford, engineer; Robert Willis Maxfield, flight test engineer; Raymond Louis Basel, flight test engineer; Edward I. Wersebe, flight test engineer.

Edmund T. ("Eddie") Allen. (San Diego Air and Space Museum Archive) — Edmund Turney Allen. (San Diego Air & Space Museum Archive)

41-0003 had first flown on 30 December 1942, piloted by Allen. During that flight, the prototype bomber suffered a major engine fire and Eddie Allen’s performance in returning the airplane to the airport later earned him the U.S. Army’s Air Medal, awarded on the specific orders of President Harry S. Truman.

Problems with the XB-29s’ Wright R-3350-13 engines had caused major delays in the B-29 testing program. The Number 2 aircraft had its engines replaced with those from the first XB-29, 41-0002. By 18 February, 41-0003 had made only eight flights, with a total flight time of 7 hours, 27 minutes.

The ninth test flight of 41-0003 was planned to test the climb performance to 25,000 feet (7,620 meters) and to collect engine cooling data.

At 12:17 p.m., 41-0003 was climbing through 5,000 feet (1,524 meters) when the #1 engine (the outboard engine on the left wing) caught fire. The engine was shut down and CO2 fire extinguishers were activated. Eddie Allen began a descent and turned back toward Boeing Field.

The wind was out of the south at 5 miles per hour (2.24 meters per second) so it was decided to land on Runway 13, the southeast/northwest runway. At 12:24, radio operator Harry Ralston reported that the XB-29 was 4 miles (6.4 kilometers) northeast of the field at 1,200 feet (366 meters).

The airplane was in the landing pattern turning from the downwind leg to the base leg when at 12:25 an explosion occurred. Ralston was heard to say, “Allen, better get this thing down in a hurry. The wing spar is burning badly.”

In order to save weight, various parts of the Wright R-3350 engine were made of magnesium, a flammable metal which burned at a very high temperature. With an engine on fire, the bomber’s wing structure was extremely vulnerable.

The prototype bomber was now shedding parts and left a trail behind it on the ground. The fire was now burning inside the fuselage. Three crew members bailed out but the altitude was too low and they were killed.

At 12:26 p.m., Boeing XB-29 41-0003 crashed into the Frye Meat Packing Plant, south of downtown Seattle, and exploded. Nearly 5,000 gallons (18,927 liters) of gasoline started a massive fire. The 8 men still aboard the prototype bomber were killed, as were 20 employees inside the building. A firefighter who responded was also killed.

Frye packing plant fire, 18 February 1943. (Seattle Post-Intelligencer) — The Frye packing plant on fire, 18 February 1943. (Seattle Post-Intelligencer)

Three XB-29 prototypes were built. The XB-29 was 98 feet, 2 inches (29.896 meters) long with a wing span of 141 feet, 3 inches (43.053 meters), and 27 feet, 9 inches (8.458 meters) high to the top of its vertical fin. The prototype bomber had a gross weight of 105,000 pounds (47,627.2 kilograms).

Boeing XB-29-BO, 41-002, the first XB-29 built. (U.S. Air Force)

The XB-29 was powered by four 3,347.662-cubic-inch-displacement (54.858 liter) air-cooled, supercharged, Wright Aeronautical Division Cyclone 18 670C18H1 (R-3350-13) two-row 18-cylinder radial engines (also known as the Duplex-Cyclone) with a compression ratio of 6.85:1. The R-3350-13 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, using 100 octane aviation gasoline. The engines turned 17-foot-diameter (5.182 meters) three-bladed Hamilton Standard Hydromatic constant-speed propellers through a 0.35:1 gear reduction. The R-3350-13 was 76.26 inches (1.937 meters) long, 55.78 inches (1.417 meters) in diameter, and weighed 2,668 pounds (1,210 kilograms).

The XB-29 had a maximum speed of 368 miles per hour (592 kilometers per hour) and cruised at 255 miles per hour (410 kilometers per hour). Its service ceiling was 32,100 feet (9,784 meters). The airplane was designed to carry 20,000 pounds (9,072 kilograms) of bombs.

The B-29 Superfortress was the most technologically advanced—and complex—aircraft of the War. 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. It would be manufactured by Boeing at Seattle and Renton, Washington and at Wichita, Kansas; by Glenn L. Martin Company at Omaha, Nebraska; and by Bell Aircraft Corporation, Atlanta, Georgia.

There were three XB-29 prototypes; 14 YB-29 pre-production test aircraft; 2,513 B-29; 1,119 B-29A; and 311 B-29B Superfortress aircraft. The bomber served during World War II and the Korean War and continued in active U.S. service until 1960.

The employees of the Boeing plant at Wichita, Kansas donated the money to build a B-29 to be named in honor of Eddie Allen. B-29-40-BW 42-24579 flew 24 combat missions. On its final mission over Tokyo, Japan, the Eddie Allen was so badly damaged that, though it was able to reach its base on the island of Tinian, it never flew again.

Boeing B-29 Superfortress "Eddie Allen." (U.S. Air Force) — Boeing Wichita-built B-29-40-BW Superfortress 42-24579, “Eddie Allen,” of the 45th Bombardment Squadron (Very Heavy), 40th Bombardment Group (Very Heavy), XX Bomber Command, circa 1944. (U.S. Air Force)

Boeing's acknoledgemnt of the sacrifice of its flight test crew, 18 February 1943, — Boeing’s acknowledgement of the sacrifice of its flight test crew, 18 February 1943, from the annual report to the shareholders.

20 December 1957

December 20, 2023AviationAlvin Melvin Johnston, Boeing 707-121, Boeing Field, Boeing Model 707, c/n 17586, Clipper Constitution, First Flight, James R. Gannet, N708PA, Pan American World Airways, Pratt & Whitney Turbo Wasp JT3C-6, Renton Field, Renton Municipal Airport, Test Pilot, Tex Johnston, Tom LayneBryan Swopes

Boeing 707-121 N708PA, photographed during its second flight. (Boeing via Space.com) — Boeing 707-121 N708PA, photographed during its second flight on the afternoon of 20 December 1957. (Boeing)

Boeing 707-121 N708PA makes its first takeoff at 12:30 p.m., on a rainy afternoon, 20 December 1957. (Unattributed) — Boeing 707-121 N708PA makes its first takeoff at 12:30 p.m. on a rainy afternoon, 20 December 1957. (Boeing)

20 December 1957: The first production Boeing 707 jet-powered commercial airliner, N708PA, made its first flight at Renton, Washington. Alvin M. “Tex” Johnston, Boeing’s Chief of Flight Test, was in command, with co-pilot James R. Gannet and flight engineer Tom Layne. Takeoff was at 12:30 p.m., PST. Poor weather limited the first flight to just 7 minutes. The new airliner landed at Boeing Field. Later that day, a second flight was made, this time with a duration of 1 hour, 11 minutes.

N708PA (Serial Number 17586, Line Number 1) was a Model 707-121. The new airliner had been sold to Pan American World Airways, the launch customer, as part of an order for twenty 707s in October 1955.

Boeing test pilot Alvin M. "Tex" Johnston in the cockpit of of the 367–80. (LIFE) — Boeing’s Chief of Flight Test, Alvin M. “Tex” Johnston, in the cockpit of of the 367–80, “Dash Eighty,” 1954. (LIFE Magazine via Jet Pilot Overseas)

The Boeing Model 707 was developed from the earlier Model 367–80, the “Dash Eighty,” prototype for an air-refueling tanker which would become the KC-135A Stratotanker. The 707 was a four-engine jet transport with swept wings and tail surfaces. The leading edge of the wings were swept at a 35° angle.

N708PA was initially used for flight testing by Boeing. Once this was completed, it was prepared for commercial service and delivered to Pan American at San Francisco International Airport (SFO), 30 November 1958. Pan Am named the new airliner Clipper Constitution.

Boeing 707-121 708PA under maintenance at Renton, Washington. (Boeing) — Boeing 707-121 N708PA under maintenance at Renton, Washington. (Boeing)

In February 1965, the airliner was upgraded to 707-121B standards, which replaced the original turbojet engines with quieter, more efficient Pratt & Whitney JT3D-1 turbofan engines which produced 17,000 pounds of thrust. The wing inboard leading edges were modified to the design of the Model 720 and there was a longer horizontal tail plane.

Clipper Constitution flew for Pan Am for nearly seven years, until 17 September 1965 when it crashed into Chances Peak, a 3,002 foot (915 meters) volcano on the Caribbean island of Montserrat. The point impact was 242 feet (74 meters) below the summit. All aboard, a crew of 9 and 21 passengers, were killed.

Boeing 707-121 N708PA, with both Boeing and Pan American corporate markings. (Unattributed)

The Boeing Model 707-121 was a four-engine jet transport with swept wings and tail surfaces. The leading edge of the wings were swept at a 35° angle. The airliner had a flight crew of four: pilot, co-pilot, navigator and flight engineer.

The 707-121 was 145 feet, 1 inch (44.221 meters) long with a wing span of 130 feet, 10 inches (39.878 meters). The top of the vertical fin stood 42 feet, 5 inches (12.929 meters) high. The 707 pre-dated the ”wide-body” airliners, having a fuselage width of 12 feet, 4 inches (3.759 meters). The airliner’s empty weight is 122,533 pounds (55,580 kilograms). Maximum take off weight is 257,000 pounds (116,573 kilograms).

The first versions were powered by four Pratt & Whitney Turbo Wasp JT3C-6 turbojet engines, producing 11,200 pounds of thrust (49,820 kilonewtons), and 13,500 pounds (60.051 kilonewtons) with water injection. This engine was a civil variant of the military J57 series. It was a two-spool axial-flow turbojet engine with a 16-stage compressor and 2 stage turbine. The JT3C-6 was 11 feet, 6.6 inches (3.520 meters) long, 3 feet, 2.9 inches (0.988 meters) in diameter, and weighed 4,235 pounds (1,921 kilograms).

At MTOW, the 707 required 11,000 feet (3,352.8 meters) of runway to take off.

The 707-121 had a maximum speed of 540 knots (1,000 kilometers per hour). It’s range was 2,800 nautical miles (5,186 kilometers).

The Boeing 707 was in production from 1958 to 1979. 1,010 were built. Production of 707 airframes continued at Renton until the final one was completed in April 1991. As of 2011, 43 707s were still in service.

Boeing 707-121 N708PA retracts its landing gear after taking off at Seattle Tacoma Airport. (Unattributed) — Boeing 707-121 N708PA landing at Seattle Tacoma Airport. (Unattributed)

17 December 1947

December 17, 2023Aviation46-065, 46-066, Bob Robbins, Boeing Field, Boeing XB-47 Stratojet, Bomber, Edward Scott Osler, First Flight, General Electric J35-GE-7, Model 450, Moses Lake, Prototype, Robert M. Robbins, Scott Osler, Test PilotBryan Swopes

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

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 Air Force Base, five miles north of the town of 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.

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. (United States Air Force 061024-F-1234S-004) — Boeing XB-47 Stratojet 46-065. (U.S. Air Force 061024-F-1234S-004)

The first prototype, 46-065, 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) at 7,700 r.p.m. (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 prototype had a maximum speed of 502 knots (578 miles per hour/930 kilometers per hour/0.80 Mach) at 15,000 feet (4,572 meters). The combat speed was 462 knots (532 miles per hour/856 kilometers per hour/0.70 Mach) at 35,000 feet (10,668 meters). The prototype’s empty weight was 74,623 pounds (33,848 kilograms), while its maximum takeoff weight was 162,500 pounds (73,709 kilograms). It required a ground run of 11,900 feet (3,627 meters), or 4,800 feet (1,463 meters) with JATO assist. The bomber could climb at a rate of 3,650 feet per minute (18.5 meters per second) at Sea Level, at combat weight and maximum power. The service ceiling was 37,500 feet (11,430 meters). The XB-47 carried 9,957 gallons (37,691 liters) of fuel. The combat radius was 1,175 nautical miles (1,352 statute miles/2,176 kilometers) with a 10,000 pound (4,536 kilogram) bomb load.

Planned armament (though the XB-47s were delivered without it) consisted of two .50-caliber machine guns in a tail turret, with 1,200 rounds of ammunition, and 10,000 pounds (4,536 kilograms) of bombs.

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, mounted forward of the leading edge.

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)

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 061024-F-1234S-003)

XB-47 45-065 stalled while landing at Larson Air Force Base, near Moses Lake, Washington, 18 August 1951. The crew of three escaped uninjured. The airplane suffered major structural damage. It was returned to Boeing at Seattle, Washington in 1953. The second prototype, XB-47 46-066, is in the collection of the Air Force Flight Test Museum, Edwards Air Force Base, California.

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