The Boeing 377 Stratocruiser was a large long-range airliner developed from the C-97 Stratofreighter military transport, itself a derivative of the B-29 Superfortress. The Stratocruiser's first flight was on July 8, 1947.[3] Its design was advanced for its day; its relatively innovative features (though neither completely new) included two passenger decks and a pressurized cabin. It could carry up to 100 passengers on the main deck plus 14 in the lower deck lounge; typical seating was for 63 or 84 passengers or 28 berthed and five seated passengers.
The Boeing 377 production lineBerths and seating aboard a 377
The Boeing 377 Stratocruiser was a civil derivative of the Boeing Model 367, the Boeing C-97 Stratofreighter, which first flew in late 1944. William Allen, who had become president of the Boeing Company in September 1945, sought to introduce a new civilian aircraft to replace reduced military production after World War II.[4] Boeing saw in their large-bodied, fast, and long-ranged military transport potential for a passenger aircraft suited for premium service on long transoceanic routes, expanding on the precedent set by their Boeing 314 Clipper with Pan American World Airways. Despite a recession in late 1945, Allen ordered 50 Stratocruisers, spending capital on the project without an order from an airline customer.[5] His gamble that customers would be interested in Boeing's unique and expensive new airplane turned out to be correct for a brief period.
On November 29, 1945 Pan American World Airways (Pan Am) became the launch customer with the largest commercial aircraft order in history, a $24,500,000 order for 20 Stratocruisers.[5] Earlier in 1945 a Boeing C-97 had flown from Seattle to Washington, D.C. nonstop in six hours and four minutes; with this knowledge, and with Pan Am President Juan Trippe's high regard for Boeing after their success with the Boeing 314 Clipper, Pan Am was confident in ordering the expensive plane.[5][6]
The 377 shared the distinctive design of the C-97, with a "double-bubble" fuselage cross-section, resembling a figure-8, with the smaller loop on the bottom, with 6,600 cubic feet (190 m3) of interior space shared between two passenger decks. Outside diameter of the upper lobe was 132 inches, compared to 125 inches for the DC-6 and other Douglas types (and 148 inches for today's 737). The lower deck served as a lounge, seating 14. The 377 had innovations such as higher cabin pressure and air conditioning; the superchargers on the four Pratt & Whitney R-4360 engines increased power at altitude and allowed constant cabin pressure.[7]
The wing was the Boeing 117 airfoil. In all, 4,000,000 man-hours went into the engineering of the 377.[8] It was one of a few double deck airliners, another being its French contemporary, the Breguet Deux-Ponts, as well as Boeing's own 747 and the Airbus A380. A total of 56 were built, one prototype (later reconditioned) and 55 production aircraft.
The first flight of the 377 was on July 8, 1947, two years after the first commercial order. The flight test fleet of three 377s underwent 250,000 mi (217,000 nmi; 402,000 km) of flying to test its limits before certification.[9]
Adoption of the Stratocruiser got a boost from the US government, with a controversial incentive package offered to Northwest Orient Airlines for its purchase. Its components were unusually generous mail contracts offered to Northwest for opening new routes to Hawaii and points in the western Pacific region that they were invited to apply for, and a Reconstruction Finance Corporation loan earmarked for the purchase of a fleet of Stratocruisers. Pan-Am saw Northwest's mail contract deal and appealed for new terms in their own international mail contracts, which were granted much to the consternation of Trans World Airlines, who were able to provide the same Atlantic mail services as Pan-Am with lower operating costs. The Northwest deal led to allegations of graft and political favoritism towards Boeing.[10]
The other carriers who adopted the Stratocruiser were British Overseas Airways Corporation, American Overseas Airlines (merged with Pan Am in 1950) and United Airlines. The last 377 was delivered to BOAC in May 1950. On this delivery flight, Boeing engineer Wellwood Beall accompanied the final 377 to England, and returned with news of the de Havilland Comet, the first jet airliner, and its appeal.[7] The tenure of the Stratocruiser with United ended in 1954, when United had the opportunity to sell them to BOAC after finding them unprofitable without the extra mail subsidies enjoyed by Pan Am and Northwest.
Only 56 were built, one prototype (later reconditioned) and 55 production aircraft. As a result of low production volume, Boeing lost $7 million on the aircraft.[11]
As the launch customer, Pan Am was the first to begin scheduled flights, from San Francisco to Honolulu in April 1949. At the end of 1949 Pan Am, BOAC and American Overseas Airlines (AOA) were flying 377s transatlantic, while Northwest Orient Airlines was flying in the United States; in January 1950 United began flights from San Francisco to Honolulu. Stratocruisers were pressed into emergency military service after the onset of the Korean War.[10] In late 1950 Northwest Stratocruisers were serving New York City, Chicago, Detroit, Minneapolis/St. Paul, Milwaukee, Spokane, Seattle, and Honolulu.[12]
By late 1952 Northwest Stratocruisers replaced DC-4s to Tokyo via Anchorage, Alaska;[13] Northwest replaced the Stratocruiser on the Honolulu run in 1953[14] and to Tokyo in 1955.[15] For a short time Pan Am 377s flew to Beirut, Lebanon, but after 1954 no 377 was scheduled east of Europe or west of Singapore. In 1954, United Stratocruisers flew Los Angeles to Honolulu and between Seattle and San Francisco;[16] United's B377 flights to Honolulu were all first class. In 1955 BOAC 377s had 50 First Class seats (fare $400 one way New York to London) or 81 Tourist seats (fare $290).[17] In 1956 Pan Am 377s flew from Los Angeles and San Francisco to Sydney with stops at Honolulu, Canton Island and Suva (via Nadi Airport in Fiji).[18]
By 1958 Pan Am was operating the Stratocruiser between Seattle, Washington and Fairbanks, Juneau and Ketchikan, Alaska and between Seattle and Whitehorse, Yukon.[19] Within six years of first delivery, the Stratocruiser had carried 3,199,219 passengers; it had completed 3,597 transcontinental flights, and 27,678 transatlantic crossings, and went between the United States and South America 822 times. In these first six years, the Stratocruiser fleet had flown 169,859,579 miles (273,362,494 km).[7]
The 377 was one of the most advanced and capable of the propeller-driven transports, and among the most luxurious,[8] but it was troubled by reliability issues and maintenance costs. Problems included catastrophic failures of propellers, failures of propeller pitch control leading to overspeed incidents, problems related to the poor thermal design of the engine, and aerodynamic problems arising from design constraints imposed by the engine's thermal problems.[10][20] Its service record was marred by a high incidence of in-flight emergencies and hull-loss accidents related to those issues.[21] The propellers were the subject of Airworthiness Directives in 1955, 1957, and 1958.[21][20]
In 1953 "United's [Chief Executive] Ray Ireland ...described the Stratocruiser as unbeatable in luxury attraction but is uneconomical. Ireland said PAA's Stratocruiser competition to Hawaii induced United to buy the plane originally."[22] In 1950 United's seven 377s averaged $2.46 "direct operating cost" per plane-mile, and "Indirect costs are generally considered to be equal or greater than the direct costs."[23] Most operators were using Stratocruisers on long-range routes where higher prices could be charged, off-setting the higher operating costs.[24]
The exception was Northwest Airlines, who managed to keep the aircraft competitive on shorter U.S. domestic routes where the aircraft's higher payload capacity benefited from lower fuel weights. United however could not integrate their six-plane fleet of 377s. By 1954 the lack of spares and the inability to cross-train their Douglas crews with the type relegated their Stratocruisers primarily to their Hawaii route, where they faced stiff competition from Pan American and Northwest. By the end of that year the six United 377s were all sold to BOAC in a deal orchestrated by Douglas Aircraft. BOAC, which was short of aircraft after the grounding of the Comet 1, paid between US$895,000 and US$995,000 per unit and spares for what were essentially five-year-old aircraft. An equivalent brand new Douglas DC-7 cost US$775,000 (~$6.3 million in 2021) in 1954.[25]
Boeing set never-exceed speed at 351 mph (305 kn; 565 km/h) IAS but in testing, the 377 reached 409 mph (355 kn; 658 km/h) IAS (about 500 mph (430 kn; 800 km/h) TAS) in a 15–20 degree dive at 13,500 ft (4,100 m);[26] another report[27] said it reached 498 mph (801 km/h) true air speed while diving from 21,000 feet (6,400 m) altitude to 12,000 feet (3,700 m) in 50 seconds using "full rated power". Typical airline cruise was less than 300 mph (260 kn; 480 km/h); in August 1953, Pan Am and United 377s (and United DC-6s) were scheduled between Honolulu and San Francisco (2,398 mi (3,859 km)) in 9 h 45 min each way.
The longest (by distance) 377 nonstop flights were made by Pan Am from Tokyo to Honolulu during four winter seasons beginning in 1952–1953. In January 1953, two nonstops a week were scheduled with a flight time of 11 hr 1 min due to tailwinds; the following August all flights took 19 hours, with a stop at Wake Island Airfield. In winter 1953-54 one Tokyo-Honolulu flight took 9 hr 35 min for 3,853 great-circle miles (6,201 km).[28]
By 1960 Stratocruisers were being superseded by jets: the de Havilland Comet, Boeing 707, and Douglas DC-8. The last flight of the 377 with United was in 1954, the last with BOAC was in 1959, and the last with Northwest was in September 1960. In November 1960 only a weekly Pan Am Honolulu to Singapore flight remained, and the 377 was retired by Pan Am in 1961. High operating costs (notably the fuel consumption and maintenance of the Wasp Major engines) led to rapid abandonment of the 377 with the onset of the jet era.[10] Its contemporaries such as the Douglas DC-6 and the Lockheed Constellation continued longer, on secondary routes or rebuilt as freighters. A few 377s were sold to smaller airlines, used as freighters, or converted by Aero Spacelines into heavily modified enlarged freighters called Guppies.[29]
During 1959 and 1960, Transocean Airlines assembled a fleet of fourteen at bargain prices. In 1960 TOA went bankrupt and only four were in operable condition. The hulks were stored at Oakland International Airport through the 1960s and cannibalized for parts, contributing some to the Aero Spacelines Guppies.[10] Five remaining 377s were modified by Bedek Aviation to resemble former U.S. Air Force Model 367 Stratofreighters and pressed into service with the Israeli Defense Force. Two were shot down during the course of their service and the three remaining 377Ms were retired in 1978 and later scrapped. None of the 56 377s built were preserved for display; the IAF Museum in Israel has a C-97 (4X-FPM) on display painted to resemble their most famous 377M, Masada.
Prototype Stratocruiser; one built. Later brought up to 377-10-26 standard and sold to Pan American World Airways in 1950.
377-10-26
20 delivered to Pan American World Airways with round windows and a rear galley.
377-10-26S
10 refitted with more powerful engines and a larger fuel capacity for Pan American transatlantic flights. Called the "Super Stratocruiser".
377-10-28
Four ordered by the Scandinavian Airlines System, but taken up by BOAC after SAS cancelled the order. Aircraft had similar features to the 377-10-26.
377-10-29
Eight delivered to American Overseas Airlines with round windows for the main cabin and rectangular windows for the lower cabin as well as an aft galley. AOA was merged with Pan Am the year after their delivery.
Seven for United Air Lines. Rectangular windows on the main cabin and circular windows on the lower cabin. Sold to BOAC circa 1954.
377F
Freighter conversion.
377M
377M Anak, Israeli Air Force Museum (2007)
In the early 1960s the Israeli Air Force wanted to upgrade to the C-130 Hercules, which could lift larger payloads, but it was expensive and sales were embargoed by the United States. Israel Aircraft Industries at Ben Gurion International Airport offered to modify Boeing 377 Stratocruisers. It had a stronger cabin floor which could handle cargo, plus a C-97 military Stratocruiser tail section, which included a clamshell cargo door. These were dubbed Anak (or Giant in Hebrew) and entered service in 1964. Three of these were modified by the use of a swing tail section, similar to the Canadair CL44D-4 airliner. Two others served as aerial tankers with underwing hose reel refueling pods. Two others were ELINT-platforms for electronic reconnaissance, surveillance and electronic countermeasure (ECM) missions. These were later joined by four KC-97Gs with the flying boom system.
Aero Spacelines Guppyedit
The Pregnant Guppy heavy lifterThe turbine-powered Super Guppy of NASA
In addition to the Israeli Anaks a company called Aero Spacelines was converting old 377s to aircraft called Guppies in the 1960s. There were three types: the Pregnant Guppy, Super Guppy, and Mini Guppy.[3] They had an extension to the top of the fuselage to enable them to carry large aircraft parts between manufacturing sites.
Conversion of one 377-10-26, incorporating an enlarged upper deck and a fuselage lengthened by 16 feet to carry sections of the Saturn V rocket. One converted.
Aero Spacelines 377SG Super Guppy
A single heavy-lift transport similar to the Pregnant Guppy built by Aero Spacelines. The aircraft contained parts of a YC-97J Stratofreighter and a 377-10-26 mated with a larger main fuselage, larger tail and Pratt & Whitney T34 turboprops.
Aero Spacelines SGT-201 Super Guppy Turbine
Originally designated the 377SGT, it was similar to the 377SG, but with a more aerodynamic fuselage, a Boeing 707 nosewheel, wingspan stretched by 23 feet (7.0 m), and four Allison 501-D22C turboprops. Four were built and were used by Airbus to carry aircraft parts between its factories. In the 1990s Airbus retired them due to rising operational costs and they have been replaced with Airbus Belugas. Two of the former Airbus Industrie Super Guppies remain in Germany and France, with a third being scrapped in December 2020 after eleven years of restoration at Bruntingthorpe Aerodrome in the UK.[34] The fourth aircraft was acquired by NASA as part of a barter agreement with ESA for its role as a partner with the International Space Station.
Aero Spacelines 377MG Mini Guppy
Conversion of a 377-10-26, it featured a larger main cabin for oversize cargo, stretched wing and a hinged tail.
Aero Spacelines MGT-101 Mini Guppy Turbine
Originally designated the 377MGT. Similar to the 377MG, but powered by Allison 501-D22C turboprop engines. One built.
This aircraft type suffered 13 hull-loss accidents between 1951 and 1970 with a total of 139 fatalities. The worst single accident occurred on April 29, 1952. The aircraft type also experienced a significantly high rate of in-flight emergencies related to engine and propeller failure, resulting in Airworthiness Directives.[21][20]
Faults included structural failures of neoprene-cored propellers, failures of propeller pitch control resulting in overspeed, and failures related to engine cooling. Six propeller failures between 1950 and 1955 resulted in separation or near-separation of engines from mounts, with two resulting in hull-loss accidents. Directives were issued in 1950, 1955, and 1958 regarding enhanced maintenance and fault detection, in-flight vibration monitoring, and propeller replacement.[21]
A Directive concerning the pitch control system was issued after the October 16, 1956 hull-loss accident. A June 1957 overspeed incident occurred on Romance of the Skies, after the compliance date of the Directive and less than six months before its fatal accident of November 8, 1957.[20] No hull-loss accidents after the loss of the Romance have been attributed to an overspeed incident.[35]
September 12, 1951
United Air Lines Flight 7030, a Stratocruiser 10-34 (N31230, named Mainliner Oahu), was being used for a semi-annual instrument check of a captain. At 11:39 PDT, the flight was cleared for an ILS approach to the San Francisco Airport. The aircraft, with No. 4 propeller feathered, stalled and abruptly dived from an altitude of approximately 300 feet and was destroyed upon impact in San Francisco Bay. All three crew aboard were killed. The probable cause was an inadvertent stall at low altitude.[36]
April 29, 1952
Pan Am Flight 202, a Stratocruiser 10-26 (N1039V, named Clipper Boa Esperança aka Clipper Good Hope) en route from Buenos Aires-Ezeiza and Rio de Janeiro–Galeão to New York via Port of Spain crashed in the jungle in the south of the State of Pará. Probable causes are the separation of the second engine and propeller from the aircraft due to highly unbalanced forces followed by uncontrollability and disintegration of the aircraft. All 50 passengers and crew died in the worst-ever accident involving the Boeing 377.[37]
July 27, 1952
Pan Am Flight 201, a Stratocruiser 10-26 (N1030V) en route from New York and Rio de Janeiro-Galeão to Buenos Aires-Ezeiza suffered explosive decompression at about 12,000 feet about 20 miles south of Rio de Janeiro. A passenger was blown out and the cabin considerably damaged, but the aircraft was able to return to Rio de Janeiro and make a safe landing. The main cabin door had not been properly locked.[38][39]
December 25, 1954
A BOAC Stratocruiser 10-28 (G-ALSA, named RMA Cathay) crashed on landing at Prestwick at 0330 hours, killing 28 of the 36 passengers and crew on board. The aircraft had been en route from London to New York City, when, on approach to Prestwick, it entered a steep descent before leveling-out too late and too severely, hitting the ground short of the runway.[40]
March 26, 1955
Pan Am Flight 845/26, a Stratocruiser 10-26 (N1032V, named Clipper United States), ditched 35 miles (56 km) off the Oregon coast after the no. 3 engine and propeller tore loose from the wing, causing severe control difficulties. The aircraft sank after 20 minutes in water of about 1,600 m (5,200 ft) depth. There were four fatalities out of the 23 occupants, including two of the crew.
April 2, 1956
Northwest Orient Airlines Flight 2, a Stratocruiser 10-30 (N74608, named Stratocruiser Tokyo), ditched into Puget Sound after the flight engineer mistakenly failed to close the cowl flaps on the plane's engines, an error attributed to confusing instrument layout. Although all aboard escaped the aircraft after a textbook ditching, four passengers and one flight attendant succumbed either to drowning or to hypothermia before being rescued.
October 16, 1956
Pan Am Flight 6 ditches near HawaiiPan Am Flight 6, a Stratocruiser 10-29 (N90943, named Clipper Sovereign of the Skies), ditched northeast of Hawaii during the last leg of an around-the-world flight from Philadelphia to San Francisco after two of its four engines failed following an overspeed incident.[20] The aircraft was able to circle around USCG Pontchartrain until daybreak, when it ditched; all 31 on board survived.
November 8, 1957
Pan Am Flight 7, a Stratocruiser 10-29 (registered N90944, named Clipper Romance of the Skies), left San Francisco for Hawaii with 38 passengers and six crew. The 377 crashed around 5:25 p.m. in the Pacific Ocean. There were no survivors and the entire wreckage has never been found. Only 19 bodies and bits of debris were recovered. There is speculation that two passengers had a motive to bring the plane down. Eugene Crosthwaite, a 46-year-old purser, had shown blasting powder to a relative days prior to the flight, and had cut a stepdaughter from his will only one hour before the flight. Pan Am concluded that there was sufficient evidence that Crosthwaite was the culprit. William Payne, an ex-Navy demolitions expert, had taken out large insurance policies on himself just before the flight, and had a $10,000 debt he was desperate to pay off. The insurance investigator later suspected him of never being on the plane. His wife received at least $125,000 in payouts. It was the opinion of the flight engineer during the Sovereign incident, and a pilot who had experienced an overspeed on the Romance less than six months before its loss, that an overspeed was a likely cause of the crash. The overspeed theory calls into question whether Pan Am was in compliance with an Airworthiness Directive concerning a weakness in the pitch control system, issued in response to the Sovereign incident the previous year.[20]
June 2, 1958
A Pan Am Stratocruiser 10-26 (registration N1023V, named Clipper Golden Gate) was on a flight from San Francisco to Singapore via several intermediate stops. As the aircraft touched down at Manila (runway 06) in a heavy landing in rainy and gusty conditions, the undercarriage collapsed as a result of the hard landing. The plane skidded and swerved to the right, coming to rest 2,850 feet past the runway threshold and 27 feet from the edge of the runway. One of the passengers was killed when one of the blades of the number 3 propeller broke off, penetrating the passenger cabin.[41]
April 10, 1959
At the conclusion of a flight from Seattle to Juneau, Alaska, a Pan Am Stratocruiser 10-26 (N1033V, named Clipper Midnight Sun) undershot on final approach and collided with an embankment. The aircraft caught fire and was destroyed, but all 10 passengers and crew survived.[42]
July 9, 1959
A Pan Am Boeing Stratocruiser 10-29 (N90941, named Clipper Australia) belly landed at Haneda Airport following landing gear problems; all 59 passengers and crew on board survived, but the aircraft was written off.[43]
August 1967
An Aero Spacelines Stratocruiser 10-29 (N90942) suffered a ground collision with Stratocruiser 10-32 N402Q at Mojave, California; the aircraft was damaged beyond repair.[44]
May 12, 1970
An Aero Spacelines 377MGT (N111AS) was being test flown following conversion from a Boeing 377. During the sixth takeoff with one engine shut down, the aircraft turned and rolled to the left. The left wingtip then struck the ground and the aircraft yawed severely after which the forward fuselage struck the ground, destroying the cockpit. All four crew died.[45]
Capacity: Up to 100 passengers on main deck plus 14 in lower deck lounge; typical seating for 63 or 84 passengers or 28 berthed and five seated passengers.
Boeing 377 – Stratocruiser A very comprehensive enthusiast page on the type
The Aviation History On-Line Museum – Boeing 377 Stratocruiser
California Classic – The Boeing Model 377 Stratocruiser
Stratocruiser article excerpts
Anak (Israeli Boeing 377)
"Speedbird Stratocruiser: A New Aircraft for B.O.A.C.'s Western Route", Flight magazine, January 27, 1949
November 14, 2023
boeing, stratocruiser, large, long, range, airliner, developed, from, stratofreighter, military, transport, itself, derivative, superfortress, stratocruiser, first, flight, july, 1947, design, advanced, relatively, innovative, features, though, neither, comple. The Boeing 377 Stratocruiser was a large long range airliner developed from the C 97 Stratofreighter military transport itself a derivative of the B 29 Superfortress The Stratocruiser s first flight was on July 8 1947 3 Its design was advanced for its day its relatively innovative features though neither completely new included two passenger decks and a pressurized cabin It could carry up to 100 passengers on the main deck plus 14 in the lower deck lounge typical seating was for 63 or 84 passengers or 28 berthed and five seated passengers Boeing 377 StratocruiserA Pan Am Stratocruiser over San Francisco BayRole AirlinerNational origin United StatesManufacturer Boeing Commercial AirplanesFirst flight July 8 1947Introduction April 1 1949 with Pan American World AirwaysRetired 1963Primary user Pan American World AirwaysNumber built 56 1 2 Developed from Boeing C 97 StratofreighterVariants Aero Spacelines Pregnant GuppyAero Spacelines Super GuppyAero Spacelines Mini GuppyThe Stratocruiser was larger than the Douglas DC 6 and Lockheed Constellation and cost more to buy and operate Its reliability was poor chiefly due to problems with the four 28 cylinder Pratt amp Whitney R 4360 Wasp Major radial engines and structural and control problems with their propellers Only 55 Model 377s were built for airlines along with the single prototype A 377 was also converted into the Aero Spacelines Pregnant Guppy by John M Conroy for NASA s Gemini space program Contents 1 Design and development 2 Operational history 3 Variants 3 1 Aero Spacelines Guppy 4 Operators 5 Accidents and incidents 6 Specifications 377 7 See also 8 Notes 9 Further reading 10 External linksDesign and development edit nbsp The Boeing 377 production line nbsp Berths and seating aboard a 377The Boeing 377 Stratocruiser was a civil derivative of the Boeing Model 367 the Boeing C 97 Stratofreighter which first flew in late 1944 William Allen who had become president of the Boeing Company in September 1945 sought to introduce a new civilian aircraft to replace reduced military production after World War II 4 Boeing saw in their large bodied fast and long ranged military transport potential for a passenger aircraft suited for premium service on long transoceanic routes expanding on the precedent set by their Boeing 314 Clipper with Pan American World Airways Despite a recession in late 1945 Allen ordered 50 Stratocruisers spending capital on the project without an order from an airline customer 5 His gamble that customers would be interested in Boeing s unique and expensive new airplane turned out to be correct for a brief period On November 29 1945 Pan American World Airways Pan Am became the launch customer with the largest commercial aircraft order in history a 24 500 000 order for 20 Stratocruisers 5 Earlier in 1945 a Boeing C 97 had flown from Seattle to Washington D C nonstop in six hours and four minutes with this knowledge and with Pan Am President Juan Trippe s high regard for Boeing after their success with the Boeing 314 Clipper Pan Am was confident in ordering the expensive plane 5 6 The 377 shared the distinctive design of the C 97 with a double bubble fuselage cross section resembling a figure 8 with the smaller loop on the bottom with 6 600 cubic feet 190 m3 of interior space shared between two passenger decks Outside diameter of the upper lobe was 132 inches compared to 125 inches for the DC 6 and other Douglas types and 148 inches for today s 737 The lower deck served as a lounge seating 14 The 377 had innovations such as higher cabin pressure and air conditioning the superchargers on the four Pratt amp Whitney R 4360 engines increased power at altitude and allowed constant cabin pressure 7 The wing was the Boeing 117 airfoil In all 4 000 000 man hours went into the engineering of the 377 8 It was one of a few double deck airliners another being its French contemporary the Breguet Deux Ponts as well as Boeing s own 747 and the Airbus A380 A total of 56 were built one prototype later reconditioned and 55 production aircraft The first flight of the 377 was on July 8 1947 two years after the first commercial order The flight test fleet of three 377s underwent 250 000 mi 217 000 nmi 402 000 km of flying to test its limits before certification 9 Adoption of the Stratocruiser got a boost from the US government with a controversial incentive package offered to Northwest Orient Airlines for its purchase Its components were unusually generous mail contracts offered to Northwest for opening new routes to Hawaii and points in the western Pacific region that they were invited to apply for and a Reconstruction Finance Corporation loan earmarked for the purchase of a fleet of Stratocruisers Pan Am saw Northwest s mail contract deal and appealed for new terms in their own international mail contracts which were granted much to the consternation of Trans World Airlines who were able to provide the same Atlantic mail services as Pan Am with lower operating costs The Northwest deal led to allegations of graft and political favoritism towards Boeing 10 The other carriers who adopted the Stratocruiser were British Overseas Airways Corporation American Overseas Airlines merged with Pan Am in 1950 and United Airlines The last 377 was delivered to BOAC in May 1950 On this delivery flight Boeing engineer Wellwood Beall accompanied the final 377 to England and returned with news of the de Havilland Comet the first jet airliner and its appeal 7 The tenure of the Stratocruiser with United ended in 1954 when United had the opportunity to sell them to BOAC after finding them unprofitable without the extra mail subsidies enjoyed by Pan Am and Northwest Only 56 were built one prototype later reconditioned and 55 production aircraft As a result of low production volume Boeing lost 7 million on the aircraft 11 Operational history edit nbsp A United Airlines 377 over the Golden Gate Bridge nbsp A BOAC StratocruiserAs the launch customer Pan Am was the first to begin scheduled flights from San Francisco to Honolulu in April 1949 At the end of 1949 Pan Am BOAC and American Overseas Airlines AOA were flying 377s transatlantic while Northwest Orient Airlines was flying in the United States in January 1950 United began flights from San Francisco to Honolulu Stratocruisers were pressed into emergency military service after the onset of the Korean War 10 In late 1950 Northwest Stratocruisers were serving New York City Chicago Detroit Minneapolis St Paul Milwaukee Spokane Seattle and Honolulu 12 By late 1952 Northwest Stratocruisers replaced DC 4s to Tokyo via Anchorage Alaska 13 Northwest replaced the Stratocruiser on the Honolulu run in 1953 14 and to Tokyo in 1955 15 For a short time Pan Am 377s flew to Beirut Lebanon but after 1954 no 377 was scheduled east of Europe or west of Singapore In 1954 United Stratocruisers flew Los Angeles to Honolulu and between Seattle and San Francisco 16 United s B377 flights to Honolulu were all first class In 1955 BOAC 377s had 50 First Class seats fare 400 one way New York to London or 81 Tourist seats fare 290 17 In 1956 Pan Am 377s flew from Los Angeles and San Francisco to Sydney with stops at Honolulu Canton Island and Suva via Nadi Airport in Fiji 18 By 1958 Pan Am was operating the Stratocruiser between Seattle Washington and Fairbanks Juneau and Ketchikan Alaska and between Seattle and Whitehorse Yukon 19 Within six years of first delivery the Stratocruiser had carried 3 199 219 passengers it had completed 3 597 transcontinental flights and 27 678 transatlantic crossings and went between the United States and South America 822 times In these first six years the Stratocruiser fleet had flown 169 859 579 miles 273 362 494 km 7 The 377 was one of the most advanced and capable of the propeller driven transports and among the most luxurious 8 but it was troubled by reliability issues and maintenance costs Problems included catastrophic failures of propellers failures of propeller pitch control leading to overspeed incidents problems related to the poor thermal design of the engine and aerodynamic problems arising from design constraints imposed by the engine s thermal problems 10 20 Its service record was marred by a high incidence of in flight emergencies and hull loss accidents related to those issues 21 The propellers were the subject of Airworthiness Directives in 1955 1957 and 1958 21 20 In 1953 United s Chief Executive Ray Ireland described the Stratocruiser as unbeatable in luxury attraction but is uneconomical Ireland said PAA s Stratocruiser competition to Hawaii induced United to buy the plane originally 22 In 1950 United s seven 377s averaged 2 46 direct operating cost per plane mile and Indirect costs are generally considered to be equal or greater than the direct costs 23 Most operators were using Stratocruisers on long range routes where higher prices could be charged off setting the higher operating costs 24 The exception was Northwest Airlines who managed to keep the aircraft competitive on shorter U S domestic routes where the aircraft s higher payload capacity benefited from lower fuel weights United however could not integrate their six plane fleet of 377s By 1954 the lack of spares and the inability to cross train their Douglas crews with the type relegated their Stratocruisers primarily to their Hawaii route where they faced stiff competition from Pan American and Northwest By the end of that year the six United 377s were all sold to BOAC in a deal orchestrated by Douglas Aircraft BOAC which was short of aircraft after the grounding of the Comet 1 paid between US 895 000 and US 995 000 per unit and spares for what were essentially five year old aircraft An equivalent brand new Douglas DC 7 cost US 775 000 6 3 million in 2021 in 1954 25 Boeing set never exceed speed at 351 mph 305 kn 565 km h IAS but in testing the 377 reached 409 mph 355 kn 658 km h IAS about 500 mph 430 kn 800 km h TAS in a 15 20 degree dive at 13 500 ft 4 100 m 26 another report 27 said it reached 498 mph 801 km h true air speed while diving from 21 000 feet 6 400 m altitude to 12 000 feet 3 700 m in 50 seconds using full rated power Typical airline cruise was less than 300 mph 260 kn 480 km h in August 1953 Pan Am and United 377s and United DC 6s were scheduled between Honolulu and San Francisco 2 398 mi 3 859 km in 9 h 45 min each way The longest by distance 377 nonstop flights were made by Pan Am from Tokyo to Honolulu during four winter seasons beginning in 1952 1953 In January 1953 two nonstops a week were scheduled with a flight time of 11 hr 1 min due to tailwinds the following August all flights took 19 hours with a stop at Wake Island Airfield In winter 1953 54 one Tokyo Honolulu flight took 9 hr 35 min for 3 853 great circle miles 6 201 km 28 By 1960 Stratocruisers were being superseded by jets the de Havilland Comet Boeing 707 and Douglas DC 8 The last flight of the 377 with United was in 1954 the last with BOAC was in 1959 and the last with Northwest was in September 1960 In November 1960 only a weekly Pan Am Honolulu to Singapore flight remained and the 377 was retired by Pan Am in 1961 High operating costs notably the fuel consumption and maintenance of the Wasp Major engines led to rapid abandonment of the 377 with the onset of the jet era 10 Its contemporaries such as the Douglas DC 6 and the Lockheed Constellation continued longer on secondary routes or rebuilt as freighters A few 377s were sold to smaller airlines used as freighters or converted by Aero Spacelines into heavily modified enlarged freighters called Guppies 29 During 1959 and 1960 Transocean Airlines assembled a fleet of fourteen at bargain prices In 1960 TOA went bankrupt and only four were in operable condition The hulks were stored at Oakland International Airport through the 1960s and cannibalized for parts contributing some to the Aero Spacelines Guppies 10 Five remaining 377s were modified by Bedek Aviation to resemble former U S Air Force Model 367 Stratofreighters and pressed into service with the Israeli Defense Force Two were shot down during the course of their service and the three remaining 377Ms were retired in 1978 and later scrapped None of the 56 377s built were preserved for display the IAF Museum in Israel has a C 97 4X FPM on display painted to resemble their most famous 377M Masada Variants edit 30 31 32 33 377 10 19 Prototype Stratocruiser one built Later brought up to 377 10 26 standard and sold to Pan American World Airways in 1950 377 10 26 20 delivered to Pan American World Airways with round windows and a rear galley 377 10 26S 10 refitted with more powerful engines and a larger fuel capacity for Pan American transatlantic flights Called the Super Stratocruiser 377 10 28 Four ordered by the Scandinavian Airlines System but taken up by BOAC after SAS cancelled the order Aircraft had similar features to the 377 10 26 377 10 29 Eight delivered to American Overseas Airlines with round windows for the main cabin and rectangular windows for the lower cabin as well as an aft galley AOA was merged with Pan Am the year after their delivery 377 10 30 Ten for Northwest Orient Airlines with all rectangular windows and an aft galley 377 10 32 Six for the British Overseas Airways Corporation BOAC Had a midships galley and all cabin windows were circular 377 10 34 Seven for United Air Lines Rectangular windows on the main cabin and circular windows on the lower cabin Sold to BOAC circa 1954 377F Freighter conversion 377M nbsp 377M Anak Israeli Air Force Museum 2007 In the early 1960s the Israeli Air Force wanted to upgrade to the C 130 Hercules which could lift larger payloads but it was expensive and sales were embargoed by the United States Israel Aircraft Industries at Ben Gurion International Airport offered to modify Boeing 377 Stratocruisers It had a stronger cabin floor which could handle cargo plus a C 97 military Stratocruiser tail section which included a clamshell cargo door These were dubbed Anak or Giant in Hebrew and entered service in 1964 Three of these were modified by the use of a swing tail section similar to the Canadair CL44D 4 airliner Two others served as aerial tankers with underwing hose reel refueling pods Two others were ELINT platforms for electronic reconnaissance surveillance and electronic countermeasure ECM missions These were later joined by four KC 97Gs with the flying boom system Aero Spacelines Guppy edit nbsp The Pregnant Guppy heavy lifter nbsp The turbine powered Super Guppy of NASAIn addition to the Israeli Anaks a company called Aero Spacelines was converting old 377s to aircraft called Guppies in the 1960s There were three types the Pregnant Guppy Super Guppy and Mini Guppy 3 They had an extension to the top of the fuselage to enable them to carry large aircraft parts between manufacturing sites The first was the Pregnant Guppy followed by the Super Guppy and finally the Mini Guppy The Super Guppy and the Mini Guppy had turboprop engines Aero Spacelines 377PG Pregnant Guppy Conversion of one 377 10 26 incorporating an enlarged upper deck and a fuselage lengthened by 16 feet to carry sections of the Saturn V rocket One converted Aero Spacelines 377SG Super Guppy A single heavy lift transport similar to the Pregnant Guppy built by Aero Spacelines The aircraft contained parts of a YC 97J Stratofreighter and a 377 10 26 mated with a larger main fuselage larger tail and Pratt amp Whitney T34 turboprops Aero Spacelines SGT 201 Super Guppy Turbine Originally designated the 377SGT it was similar to the 377SG but with a more aerodynamic fuselage a Boeing 707 nosewheel wingspan stretched by 23 feet 7 0 m and four Allison 501 D22C turboprops Four were built and were used by Airbus to carry aircraft parts between its factories In the 1990s Airbus retired them due to rising operational costs and they have been replaced with Airbus Belugas Two of the former Airbus Industrie Super Guppies remain in Germany and France with a third being scrapped in December 2020 after eleven years of restoration at Bruntingthorpe Aerodrome in the UK 34 The fourth aircraft was acquired by NASA as part of a barter agreement with ESA for its role as a partner with the International Space Station Aero Spacelines 377MG Mini Guppy Conversion of a 377 10 26 it featured a larger main cabin for oversize cargo stretched wing and a hinged tail Aero Spacelines MGT 101 Mini Guppy Turbine Originally designated the 377MGT Similar to the 377MG but powered by Allison 501 D22C turboprop engines One built Operators edit nbsp Transocean Airlines nbsp United Airlines nbsp Pan Am President Juan Trippe in front of a 377 nbsp Ecuador Linea Internacional Aerea nbsp United Kingdom British Overseas Airways Corporation BOAC nbsp Israel Israeli Air Force nbsp Nigeria Nigeria Airways nbsp Sweden Svensk Interkontinental Lufttrafik part of Scandinavian Airlines System aircraft not delivered passed to BOAC nbsp United States American Overseas Airlines DAI Airways Northwest Orient Airlines Pan American World Airways Transocean Air Lines United Airlines nbsp Venezuela Rutas Aereas Nacionales SAAccidents and incidents editThis aircraft type suffered 13 hull loss accidents between 1951 and 1970 with a total of 139 fatalities The worst single accident occurred on April 29 1952 The aircraft type also experienced a significantly high rate of in flight emergencies related to engine and propeller failure resulting in Airworthiness Directives 21 20 Faults included structural failures of neoprene cored propellers failures of propeller pitch control resulting in overspeed and failures related to engine cooling Six propeller failures between 1950 and 1955 resulted in separation or near separation of engines from mounts with two resulting in hull loss accidents Directives were issued in 1950 1955 and 1958 regarding enhanced maintenance and fault detection in flight vibration monitoring and propeller replacement 21 A Directive concerning the pitch control system was issued after the October 16 1956 hull loss accident A June 1957 overspeed incident occurred on Romance of the Skies after the compliance date of the Directive and less than six months before its fatal accident of November 8 1957 20 No hull loss accidents after the loss of the Romance have been attributed to an overspeed incident 35 September 12 1951 United Air Lines Flight 7030 a Stratocruiser 10 34 N31230 named Mainliner Oahu was being used for a semi annual instrument check of a captain At 11 39 PDT the flight was cleared for an ILS approach to the San Francisco Airport The aircraft with No 4 propeller feathered stalled and abruptly dived from an altitude of approximately 300 feet and was destroyed upon impact in San Francisco Bay All three crew aboard were killed The probable cause was an inadvertent stall at low altitude 36 April 29 1952 Pan Am Flight 202 a Stratocruiser 10 26 N1039V named Clipper Boa Esperanca aka Clipper Good Hope en route from Buenos Aires Ezeiza and Rio de Janeiro Galeao to New York via Port of Spain crashed in the jungle in the south of the State of Para Probable causes are the separation of the second engine and propeller from the aircraft due to highly unbalanced forces followed by uncontrollability and disintegration of the aircraft All 50 passengers and crew died in the worst ever accident involving the Boeing 377 37 July 27 1952 Pan Am Flight 201 a Stratocruiser 10 26 N1030V en route from New York and Rio de Janeiro Galeao to Buenos Aires Ezeiza suffered explosive decompression at about 12 000 feet about 20 miles south of Rio de Janeiro A passenger was blown out and the cabin considerably damaged but the aircraft was able to return to Rio de Janeiro and make a safe landing The main cabin door had not been properly locked 38 39 December 25 1954 A BOAC Stratocruiser 10 28 G ALSA named RMA Cathay crashed on landing at Prestwick at 0330 hours killing 28 of the 36 passengers and crew on board The aircraft had been en route from London to New York City when on approach to Prestwick it entered a steep descent before leveling out too late and too severely hitting the ground short of the runway 40 March 26 1955 Pan Am Flight 845 26 a Stratocruiser 10 26 N1032V named Clipper United States ditched 35 miles 56 km off the Oregon coast after the no 3 engine and propeller tore loose from the wing causing severe control difficulties The aircraft sank after 20 minutes in water of about 1 600 m 5 200 ft depth There were four fatalities out of the 23 occupants including two of the crew April 2 1956 Northwest Orient Airlines Flight 2 a Stratocruiser 10 30 N74608 named Stratocruiser Tokyo ditched into Puget Sound after the flight engineer mistakenly failed to close the cowl flaps on the plane s engines an error attributed to confusing instrument layout Although all aboard escaped the aircraft after a textbook ditching four passengers and one flight attendant succumbed either to drowning or to hypothermia before being rescued October 16 1956 nbsp Pan Am Flight 6 ditches near Hawaii Pan Am Flight 6 a Stratocruiser 10 29 N90943 named Clipper Sovereign of the Skies ditched northeast of Hawaii during the last leg of an around the world flight from Philadelphia to San Francisco after two of its four engines failed following an overspeed incident 20 The aircraft was able to circle around USCG Pontchartrain until daybreak when it ditched all 31 on board survived November 8 1957 Pan Am Flight 7 a Stratocruiser 10 29 registered N90944 named Clipper Romance of the Skies left San Francisco for Hawaii with 38 passengers and six crew The 377 crashed around 5 25 p m in the Pacific Ocean There were no survivors and the entire wreckage has never been found Only 19 bodies and bits of debris were recovered There is speculation that two passengers had a motive to bring the plane down Eugene Crosthwaite a 46 year old purser had shown blasting powder to a relative days prior to the flight and had cut a stepdaughter from his will only one hour before the flight Pan Am concluded that there was sufficient evidence that Crosthwaite was the culprit William Payne an ex Navy demolitions expert had taken out large insurance policies on himself just before the flight and had a 10 000 debt he was desperate to pay off The insurance investigator later suspected him of never being on the plane His wife received at least 125 000 in payouts It was the opinion of the flight engineer during the Sovereign incident and a pilot who had experienced an overspeed on the Romance less than six months before its loss that an overspeed was a likely cause of the crash The overspeed theory calls into question whether Pan Am was in compliance with an Airworthiness Directive concerning a weakness in the pitch control system issued in response to the Sovereign incident the previous year 20 June 2 1958 A Pan Am Stratocruiser 10 26 registration N1023V named Clipper Golden Gate was on a flight from San Francisco to Singapore via several intermediate stops As the aircraft touched down at Manila runway 06 in a heavy landing in rainy and gusty conditions the undercarriage collapsed as a result of the hard landing The plane skidded and swerved to the right coming to rest 2 850 feet past the runway threshold and 27 feet from the edge of the runway One of the passengers was killed when one of the blades of the number 3 propeller broke off penetrating the passenger cabin 41 April 10 1959 At the conclusion of a flight from Seattle to Juneau Alaska a Pan Am Stratocruiser 10 26 N1033V named Clipper Midnight Sun undershot on final approach and collided with an embankment The aircraft caught fire and was destroyed but all 10 passengers and crew survived 42 July 9 1959 A Pan Am Boeing Stratocruiser 10 29 N90941 named Clipper Australia belly landed at Haneda Airport following landing gear problems all 59 passengers and crew on board survived but the aircraft was written off 43 August 1967 An Aero Spacelines Stratocruiser 10 29 N90942 suffered a ground collision with Stratocruiser 10 32 N402Q at Mojave California the aircraft was damaged beyond repair 44 May 12 1970 An Aero Spacelines 377MGT N111AS was being test flown following conversion from a Boeing 377 During the sixth takeoff with one engine shut down the aircraft turned and rolled to the left The left wingtip then struck the ground and the aircraft yawed severely after which the forward fuselage struck the ground destroying the cockpit All four crew died 45 Specifications 377 editData from Airliners of the World 46 General characteristicsCrew 4 flight crew cabin crew Capacity Up to 100 passengers on main deck plus 14 in lower deck lounge typical seating for 63 or 84 passengers or 28 berthed and five seated passengers Length 110 ft 4 in 33 63 m Wingspan 141 ft 3 in 43 05 m Height 38 ft 3 in 11 66 m Wing area 1 769 sq ft 164 3 m2 Empty weight 83 500 lb 37 875 kg Max takeoff weight 148 000 lb 67 132 kg Powerplant 4 Pratt amp Whitney R 4360 B6 Wasp Major 28 cylinder air cooled radial piston engines 3 500 hp 2 600 kW each Propellers 4 bladed constant speed fully feathering propellersPerformance Maximum speed 375 mph 604 km h 326 kn Cruise speed 301 mph 484 km h 262 kn Range 4 200 mi 6 800 km 3 600 nmi Service ceiling 32 000 ft 9 800 m See also editRelated development Aero Spacelines Pregnant Guppy Aero Spacelines Super Guppy Aero Spacelines Mini Guppy Boeing B 50 Superfortress Boeing C 97 Stratofreighter Boeing KC 97 StratofreighterAircraft of comparable role configuration and era Canadair CL 44 Boeing B 29 Superfortress Douglas DC 7 Lockheed L 188 Electra Lockheed Constellation Lockheed L 049 Constellation Lockheed L 649 Constellation Lockheed L 749 Constellation Lockheed L 1049 Super Constellation Lockheed L 1649 Starliner Lockheed R6V Constitution Tupolev Tu 70Notes edit Boeing Historical Snapshot Model 377 Stratocruiser Commercial Transport www boeing com Boeing 377 Stratocruiser www aviation history com a b Boeing History Stratocruiser Commercial Transport Boeing com July 8 1947 Archived from the original on June 6 2012 Retrieved June 18 2012 Redding and Yenne 1997 p 68 a b c Redding and Yenne 1997 p 69 Pask Alexander September 28 2019 Boeing 377 Stratocruiser The Original Jumbo Jet International Aviation HQ a b c Redding and Yenne 1997 p 71 a b Redding and Yenne 1997 p 70 Pushing the Envelope The American Aircraft Industry by Donald M Pattillo page needed a b c d e Ernest K Gann s Flying Circus Lady with a past Ovi ch Retrieved June 18 2012 Simons Graham M January 30 2018 Boeing 707 Group A History Pen and Sword ISBN 978 1 4738 6136 7 http www timetableimages com Sept 24 1950 Northwest Orient timetable International Schedules timetableimages com Retrieved May 4 2023 Complete Schedules timetableimages com Retrieved May 4 2023 Complete Schedules timetableimages com Retrieved May 4 2023 http www timetableimages com Aug 1 1954 United timetable Flight 28 October 1955 p671 http www timetableimages com July 1 1956 Pan American timetable http www timetableimages com Jan 1 1958 Pan American timetable a b c d e f Herken Gregg Fortenberry Ken September 2004 The Mystery of the Lost Clipper Air amp Space Retrieved February 3 2014 a b c d Carl Kuhns Boeing Model 377 Stratocruiser Propeller Woes PDF Retrieved March 18 2018 Aviation Week 31 August 1953 p 57 The article discusses CAB rulings and Ireland was perhaps speaking at a hearing American Aviation 23 July 1951 p37 Classic Airliners Boeing Stratocruiser p 64 67 Airliner Tech Series Vol 9 Boeing 377Stratocruiser p 60 61 American Aviation 8 January 1951 p 23 The Aeroplane 15 October 1948 Aviation Week 15 Feb 1954 p100 Wilson 1998 p 16 Flight Simulation is Stimulation Boeing 377 Stratocruiser Archived August 13 2011 at the Wayback Machine Retrieved 3 31 11 Israeli Weapons com Anak Boeing 377 Retrieved 3 31 11 Flickriver Israel07 Israel Air Force Museum by brewbooks Retrieved 3 31 11 All About Guppys com Retrieved 4 1 11 The end of Bruntingthorpe s Super Guppy scramble nl November 28 2020 Retrieved May 16 2021 Aviation Safety Network gt ASN Aviation Safety Database gt Type index gt ASN Aviation Safety Database results Accident description for N31230 at the Aviation Safety Network Retrieved on 2013 11 17 Accident description for N1039V at the Aviation Safety Network Retrieved on 2011 09 15 Accident description for N1030V at the Aviation Safety Network Retrieved on 2011 09 24 Fall From Plane Kills L A Woman The Los Angeles Times July 28 1952 p 1 Retrieved March 8 2022 via Newspapers com Accident description for G ALSA at the Aviation Safety Network Retrieved on 2010 11 18 Accident description for N1023V at the Aviation Safety Network Retrieved on 2013 11 17 Accident description for N1033V at the Aviation Safety Network Retrieved on 2013 11 17 Accident description for N90941 at the Aviation Safety Network Retrieved on 2013 11 17 Accident description for N90942 at the Aviation Safety Network Retrieved on 2013 11 17 Accident description for N111AS at the Aviation Safety Network Retrieved on 2013 11 17 Wilson Stewart 1999 Airliners of the World Fyshwick Australia Aerospace Publications ISBN 1 875671 44 7 Further reading editAir Disaster Vol 4 The Propeller Era by Macarthur Job Aerospace Publications Pty Ltd Australia 2001 ISBN 1 875671 48 X Redding Robert amp Yenne Bill 1997 Boeing Planemaker to the World San Diego California Thunder Bay Press pp 68 71 ISBN 1 57145 045 9 Taylor H A Tony April July 1982 Stratocruiser Ending an Airline Era Air Enthusiast No 18 pp 37 53 ISSN 0143 5450 Wilson Stewart 1999 Airliners of the World Fyshwick Australia Aerospace Publications ISBN 1 875671 44 7 Wilson Stewart 1998 Boeing 707 Douglas DC 8 amp Vickers VC 10 Fyshwick Australia Aerospace Publications ISBN 1 875671 36 6 External links edit nbsp Wikimedia Commons has media related to Boeing 377 category Boeing 377 Stratocruiser A very comprehensive enthusiast page on the type The Aviation History On Line Museum Boeing 377 Stratocruiser California Classic The Boeing Model 377 Stratocruiser Stratocruiser article excerpts Anak Israeli Boeing 377 Speedbird Stratocruiser A New Aircraft for B O A C s Western Route Flight magazine January 27 1949 Retrieved from https en wikipedia org w index php title Boeing 377 Stratocruiser amp oldid 1180905487, wikipedia, wiki, book, books, library,
