Tag Archives: Boeing Airplane Company

4 November 1954

Boeing B-29A-40-BW Superfortress 42-4612. (U.S. Air Force)
Boeing B-29-40-BW Superfortress 42-24612. (U.S. Air Force)

4 November 1954: The Strategic Air Command retired its last B-29 Superfortress four-engine heavy bomber to the aircraft storage facility at Davis-Monthan Air Force Base, Tucson, Arizona.

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. Empty weight was 74,500 pounds (33,793 kilograms) with a maximum takeoff weight of 133,500 pounds (60,555 kilograms).

The B-29 was powered by four air-cooled, 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, which 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 357 miles per hour (575 kilometers per hour) at 30,000 feet (9,144 meters), though its normal cruising speed was 220 miles per hour (354 kilometers per hour) at 25,000 feet (7,620 meters). The bomber’s service ceiling was 33,600 feet (10,241 meters) and the combat range was 3,250 miles (5,230 kilometers).

The Superfortress could carry a maximum of 20,000 pounds (9,072 kilograms) of bombs in two bomb bays. For defense it had 12 Browning M2 .50-caliber machine guns in four remote-controlled turrets and a manned tail position.

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.)

The Superfortress could carry a maximum of 20,000 pounds (9,072 kilograms) of bombs in two bomb bays. For defense it had 12 Browning M2 .50-caliber machine guns in four remote-controlled turrets and a manned tail position.

B-29 Superfortresses in storage at Davis-Monthan Air Force Base. (LIFE Magazine)
B-29 Superfortresses in storage at Davis-Monthan Air Force Base. (LIFE Magazine)

© 2016, Bryan R. Swopes

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1 November 1954

Boeing B-29A-20-BN Superfortress 42-94012 at Davis-Monthan AFB, Arizona. (U.S. Air Force)
Boeing B-29A-20-BN Superfortress 42-94012 at Davis-Monthan AFB, Arizona. (U.S. Air Force)

1 November 1954: The United States Air Force begins to retire the Boeing B-29 Superfortress from service. In the above photograph, B-29A-20-BN 42-94012 is at the aircraft storage facility, Davis-Monthan Air Force Base, Tucson, Arizona, “The Boneyard.” The dry desert climate and hard, alkaline soil make the base ideal for long-term aircraft storage. The Santa Catalina Mountains are in the background.

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).

Boeing B-29 Superfortresses at Wichita, Kansas, 1944. (U.S. Air Force)
Boeing B-29 Superfortresses at Wichita, Kansas, 1944. (U.S. Air Force)

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 wings had a total are of 1,720 square feet ( square meters). The angle of incidence was 4° with 4° 29′ 23″ dihderal. The leading edges were swept aft 7° 1′ 26″. The bomber’s empty weight was 71,500 pounds ( kilograms) with a maximum takeoff weight of 140,000 pounds ( kilograms).

The B-29 was powered by four air-cooled, 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, which 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).

Boeing B-29A-30-BN Superfortress 42-94106, circa 1945. (U.S. Air Force)
Boeing B-29A-30-BN Superfortress 42-94106, circa 1945. (U.S. Air Force)

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 198 knots (228 miles per hour/367 kilometers per hour) at 25,000 feet (7,620 meters). At its maximum takeoff weight, the B-29 required 1 hour, 1.5 minutes to climb from Sea Level to 20,000 feet (6,096 meters). The bomber’s service ceiling was 43,200 feet (13,167 meters). The combat range was 3,445 nautical miles (3,964 statute miles/6,380 kilometers) and its maximum ferry range was 4,493 nautical miles (5,170 statute miles/8,321 kilometers).

The Superfortress could carry a maximum of 20,000 pounds (9,072 kilograms) of bombs in two bomb bays. For defense it had 12 Browning M2 .50-caliber machine guns in four remote-controlled turrets and a manned tail position. The B-29 carried 500 rounds of ammunition per gun.

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.)

B-29 Superfortresses in storage at Davis-Monthan Air Force Base. (LIFE Magazine)
B-29 Superfortresses in storage at Davis-Monthan Air Force Base. (LIFE Magazine)

© 2016, Bryan R. Swopes

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16 October 1956

Boeing 377 Stratocruiser N90943, Pan American World Airways' Sovereign of the Skies, seen over San Francisco, circa 1947. (University of Washington Libraries Digital Collections, TRA0138)
Boeing 377 Stratocruiser N90943, Pan American World Airways’ Sovereign of the Skies, seen over San Francisco, circa 1947. (University of Washington Libraries Digital Collections, TRA0138)

16 October 1956: Pan American World Airways’ Flight 6 was a scheduled around-the-world passenger flight. The final leg, Honolulu to San Francisco, was flown by a Boeing Model 377 Stratocruiser with civil registration N90943, and named Sovereign of the Skies.

The airplane had a flight crew of 7 and carried 24 passengers. The aircraft commander was Captain Richard N. Ogg, a veteran pilot with more than 13,000 flight hours accumulated over twenty years. First Officer George L. Haaker, Flight Engineer Frank Garcia, Jr., and Navigator Richard L. Brown completed the flight crew. The cabin crew were Purser Patricia Reynolds, who had been with Pan Am for over ten years, and Stewardesses Katherine S. Araki and Mary Ellen Daniel.

The flight from Honolulu to San Francisco was estimated to take 8 hours, 54 minutes. Captain Ogg had the airplane fueled for a total flight time of 12 hours, 18 minutes.

Pan American World Airlines’ Boeing 377 Stratocruiser, Clipper America. This airplane is similar to Sovereign of the Skies. (Boeing)

Flight 6 departed Honolulu at 8:24 p.m., Hawaii Standard Time, 15 October (06:24, 16 October, GMT), and climbed to 13,000 feet (3,962 meters) on course.

4 hours, 38 minutes after takeoff, Flight 6 requested a pre-planned climb to 21,000 feet (6,400 meters), at a point about half-way—in terms of flight time—between the departure point and destination, what is dramatically called “The Point of No Return” in suspense movies. (Actually, this is called the Equal Time Point: Taking into consideration forecast winds, the time to fly back to the departing point is the same as the time to continue toward the destination.)

On leveling at the new cruise altitude at 1:19 a.m. (HST), First Officer Haaker reduced engine power. The propeller for the Number 1 engine, the outside engine on the left wing, suffered a prop governor failure and began to overspeed, with engine r.p.m. actually exceeding the limits of its tachometer. This created a very dangerous condition: If the propeller turned fast enough, it could be torn apart by centrifugal force. (See This Day In Aviation, 22 March 1956, for an example.)

The crew was unable to feather the propeller, which would cause its four blades to turn parallel to the slip stream, and increasing the load on the engine while reducing aerodynamic drag. The engine and propeller continued to turn at dangerously high speed so Captain Ogg decided to force the engine to stop by cutting off its lubricating oil supply. This caused the engine to seize but the propeller continued to “windmill.”

The drag caused by the propeller slowed the airplane considerably and the three remaining engines had to run at high power for the Boeing 377 to maintain its altitude. The Number 4 engine (the outer engine on the right wing) was developing only partial power at full throttle. At 2:45 a.m., it began to backfire and had to be shut down.

The airplane began to descend toward the ocean’s surface.

With the drag of the windmilling Number 1 propeller and only two engines running, Sovereign of the Skies could fly at just 140 knots (161 miles per hour/259 kilometers per hour), not fast enough to reach San Francisco or to return to Honolulu before running out of fuel. The navigator estimated that they would run out of fuel 250 miles (402 kilometers) from land.

The United States Coast Guard kept a high endurance cutter on station between Hawaii and California, at a point known as Ocean Station November. This ship provided assistance with weather information, radio communications and was available to assist should an emergency arise aboard trans-Pacific airplanes.

USCGC Pontchartrain (WHEC 70) circa 1958. (U.S. Coast Guard)
USCGC Pontchartrain (WHEC 70) circa 1958. (U.S. Coast Guard)

On 16 October 1956, this cutter was USCGC Pontchartrain (WHEC 70), under the command of Commander William K. Earle, USCG. Pontchartrain was a 255-foot (77.7 meter) Lake-class patrol gunboat built by the U.S. Coast Guard ship yard at Curtiss Bay, Maryland, and commissioned 28 July 1945. The ship was redesignated as a high endurance cutter in 1948. Pontchartrain had a complement of 143 men.

The ship was 254 feet (77.42 meters) long, overall, with a beam of 43 feet, 1 inch (13.13 meters) and draft of 17 feet, 3 inches (5.25 meters). Its full load displacement was 1,978 tons (1,794 Metric tons). It was powered by a Westinghouse turbo-electric drive of 4,000 shaft horsepower and was capable on making 17.5 knots (20.41 miles per hour, or 32.41 kilometers per hour). Its maximum range was 10,376 miles (19,216 kilometers).

Pontchartrain was armed with a single 5-inch/38-caliber naval gun forward. It carried Hedgehog anti-submarine mortars and Mk 23 acoustic-homing antisubmarine torpedoes.

Captain Ogg notified Ponchartrain that he intended to ditch the airliner near the ship. The Coast Guard provided Captain Ogg with wind and wave information—five-foot (1.5 meter) swells, wind at eight knots (4 meters per second) from the northwest—and advised the best heading for ditching. The ship laid a trail of foam to mark this course.

Pan American World Airways Flight 6, a Boeing 377 Stratocruiser, ditches in the North Pacific Ocean near USCGC Pontchartrain (WHEC 70), 6:15 am., 16 October 1956. (U.S. Coast Guard)
Pan American World Airways Flight 6, a Boeing 377 Stratocruiser, ditches in the North Pacific Ocean near USCGC Pontchartrain (WHEC 70), 6:15 am., 16 October 1956. (U.S. Coast Guard)

At 6:15 a.m., at approximately 90 knots airspeed (104 miles per hour/167 kilometers per hour), the Boeing 377 landed on the water. A wing hit a swell, spinning the airplane to the left. The tail broke off and the airplane began to settle.

Pan American World Airways’ Boeing 377 Stratocruiser, Sovereign of the Skies, with its fuselage broken after ditching in the North Pacific Ocean, 16 October 1956. (Pan Am Historical Foundation/The New York Times)

Injuries were minor and all passengers and crew evacuated the airliner. They were immediately picked up by Pontchartrain.

Captain Ogg and Purser Reynolds were the last to leave the airplane.

Twenty minutes after touching down, at 6:35 a.m., Sovereign of the Skies sank beneath the ocean’s surface.

Sovereign of the Seas sinks into the Pacific Ocean, 16 October 1956. (U.S. Coast Guard)
Sovereign of the Skies sinks into the Pacific Ocean, 16 October 1956. (U.S. Coast Guard)

Pan American’s Sovereign of the Skies was a Boeing Model 377-10-29, construction number 15959, originally operated by American Overseas Airlines as Flagship Holland, and later, Flagship Europe. Pan Am acquired the airliner during a merger. On 16 October 1956, the airplane had accumulated 19,820:51 total time on the airframe (TTAF) since it was built.

The Boeing 377 was a large, four-engine civil transport which had been developed, along with the military C-97 Stratofreighter, from the World War II B-29 Superfortress long-range heavy bomber. It utilized the wings and engines of the improved B-50 Superfortress. The airplane was operated by a flight crew of four. It was a double-deck aircraft, with the flight deck, passenger cabin and galley on the upper deck and a lounge and cargo compartments on the lower. The airliner was pressurized, and could maintain Sea Level atmospheric pressure while flying at 15,500 feet (4,724 meters). The Model 377 could be configured to carry up to 100 passengers, or 28 in sleeping births.

The Stratocruiser was 110 feet, 4 inches (33.630 meters) long with a wingspan of 141 feet, 3 inches (43.053 meters) and overall height of 38 feet, 3 inches (11.659 meters). Empty weight was 83,500 pounds (37,875 kilograms) and the maximum takeoff weight was 148,000 pounds (67,132 kilograms). Sovereign of the Skies had a gross weight of 138,903 pounds (63,005 kilograms) when it took off from Honolulu.

Crew members of Pan American World Airways Flight 6 receive commendations for their service during the emergency of 16 October 1956. Left to right, Captain Richard N. Ogg; Navigator Richard L. Brown; Purser Patricia Reynolds; (unidentified); First Officer George L. Haaker; Flight Engineer Frank Garcia, Jr.. (Pan Am Historical Foundation/The New York Times)

The airliner was powered by four air-cooled, supercharged 4,362.49-cubic-inch-displacement (71.489 liter) Pratt & Whitney Wasp Major B6 four-row, 28-cylinder radial engines which had a Normal Power rating of 2,650 horsepower at 2,550 r.p.m., and 2,800 horsepower at 2,550 r.p.m. Maximum Continuous. It produced 3,250 horsepower at 2,700 r.p.m. for takeoff (3,500 horsepower with water injection). The engines drove four-bladed Hamilton-Standard Hydromatic, 24260 constant-speed propellers with a diameter of 17 feet, 0 inches (5.182 meters) through a 0.375:1 gear reduction. The Wasp Major B6 was 8 feet, 0.50 inches (2.451 meters) long, 4 feet, 7.00 inches (1.397 meters) in diameter, and weighed 3,584 pounds (1,626 kilograms).

The 377 had a cruise speed of 301 miles per hour (484 kilometers per hour) and a maximum speed of 375 miles per hour (604 kilometers per hour). During testing by Boeing, a 377 reached 409 miles per hour (658 kilometers per hour). Its service ceiling was 32,000 feet (9,754 meters) and the range was 4,200 miles (6,759 kilometers).

Boeing built 56 Model 377 Stratocruisers, with Pan American as the primary user, and another 888 military C-97 Stratofreighter and KC-97 Stratotankers.

A U.S. Coast Guard film of the incident can be seen at:

© 2018, Bryan R. Swopes

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15 October 1937

The Boeing XB-15 takes off on its first flight, Boeing Field, 15 October 1937. (U.S. Air Force)

15 October 1937: Test pilot Edmund Turney (“Eddie”) Allen, a consulting engineer to Boeing, and Major John D. Korkille, Air Corps, United  States Army, made the first flight of the prototype Boeing XB-15, 35-277, at Boeing Field, Seattle, Washington. Major Corkille reported that the airplane “handled easily and maneuvered readily.”

The flight deck of the Boeing XB-15. The radio operator’s station is on the left, and the navigator’s on the right. (The Boeing Company)

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 (8,047 kilometers) 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.

The Boeing Model 294 (XB-15) at Boeing Field, Seattle, Washington. The prototype bomber was rolled out for engine tests, 27 September 1937. (The Boeing Company)

Designers had planned to use an experimental 3,421.19-cubic-inch-displacement (56.063 liter) liquid-cooled, supercharged and turbosupercharged Allison V-3420 twenty-four cylinder, four-bank “double V” engine which 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.

Boeing XB-15 35-277. (U.S. Air Force)
Boeing XB-15 35-277. (U.S. Air Force)
Boeing XB-15 35-277. (U.S. Air Force)

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.

Boeing XB-15 35-277

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).

As built, the XB-15 was powered by four air-cooled, supercharged, 1,829.39-cubic-inch-displacement (29.978 liter) Pratt & Whitney Twin Wasp S1B3-G (R-1830-11) two-row 14-cylinder radial engines, rated at 850 horsepower at 2,450 r.p.m. at 5,000 feet (1,524 meters), and 1,000 horsepower at 2,600 r.p.m. for take off. The engines 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).

These gave the experimental airplane a maximum speed of 197 miles per hour (317 kilometers per hour) at 5,000 feet (1,524 meters) and a cruise speed of 152 miles per hour (245 kilometers per hour) at 6,000 feet (1,829 meters). The service ceiling was 18,900 feet (5,761 meters) and maximum range was 5,130 miles (8,256 kilometers).

The Boeing XB-15 experimental long-range heavy bomber flies in formation with a Boeing YP-29 pursuit. (U.S. Air Force)

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 redesignated XC-105. In 1945 it was stripped and abandoned at Albrook Field, Territory of the Canal Zone, Panama.

The XB-15 set several Fédération Aéronautique Internationale (FAI) world records:  On 30 July 1939, 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 same flight set a second record by carrying 10,000 kilograms (22,046 pounds) to an altitude of 8,228 feet (2,508 meters).² On 2 August 1939, the XB-15 set a World Record for Speed Over a Closed Circuit of 5000 Kilometers With 2000 Kilogram Payload, at an average speed of 267.67 kilometers per hour (166.32 miles per hour).³

Boeing XB-15 35-277. (LIFE Magazine)

¹ FAI Record File Number 8739

² FAI Record File Number 8740

³ FAI Record File Number 10865

© 2017, Bryan R. Swopes

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10 October 1933

United Air Lines' Boeing 247, NC13304
United Air Lines’ Boeing 247, NC13304, over Chicago, Illinois, 1933.

10 October 1933: A United Air Lines Boeing 247, civil registration NC13304, was on Trip 23, a scheduled transcontinental flight from Newark, New Jersey to Oakland, California, with intermediate stops at Cleveland, Ohio, and Chicago, Illinois. The airliner, which had been in service only six months, was carrying a crew of three with four passengers.

While enroute from Cleveland to Chicago, NC13304 exploded in mid-air. It crashed near Jackson Township, approximately five miles southeast of Chesterton, Indiana. There was a second explosion after the crash. All seven persons aboard were killed.

Boeing 247 NC13304 (Boeing)
Boeing 247 NC13304 (Boeing)

NC13304, serial number 1685, was the fourth Model 247 to be built. The Boeing 247 is considered to be the first modern airliner because of its all-metal, semi-monocoque construction, cantilevered wing and retractable landing gear. It was 50 mph faster than its contemporaries, and could climb on one engine with a full load. It carried a pilot, co-pilot, flight attendant and up to ten passengers.

The Boeing 247 was powered by two air-cooled, supercharged 1,343.80-cubic-inch-displacement (22.021 liter) Pratt & Whitney Wasp S1H1 nine-cylinder radial engines with a compression ratio of 6:1. The S1H1 was a direct-drive engine. It had a Normal Power rating of 550 horsepower at 2,200 r.p.m., at 8,000 feet (2,438 meters), and 600 horsepower at 2,250 r.p.m for takeoff. The engine was 3 feet, 6.94 inches (1.091 meters) long, 4 feet, 3.75 inches (1.314 meters) in diameter, and weighed 864 pounds (392 kilograms).

The Boeing 247 had a maximum speed of 200 miles per hour (320 kilometers per hour) with a cruising speed of 188 miles per hour (304 kilometers per hour). It had a range of 745 miles (1,200 kilometers) and a service ceiling of 25,400 feet (7,260 meters).

UNited Air Lines Boeing 247 NC13304 loading U.S. mail at Chicago, Illinois, 1933.
United Air Lines Boeing 247 NC13304 loading cargo at Chicago, Illinois, 1933.

The investigation determined that the airliner’s tail had been blown off by a nitroglycerin bomb which had been placed in the baggage compartment.

The pilots had closed both throttles, turned off the magneto switches and pulled the master switch prior to impact.

This was the first proven case of a commercial aircraft destroyed by sabotage. No suspects or motive for the crime were ever discovered.

Wreckage of NC13304
Wreckage of NC13304 (Acme Newspapers)

© 2016, Bryan R. Swopes

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