Tag Archives: Aircraft Accident

19 February 1985

February 19, 2025Aviation22805, Aircraft Accident, Airliner, Boeing 747SP, Boeing 747SP-09, China Airlines, China Airlines Flight 006, Dynasty Six, Ju Yu Chang, Min-Yuan Ho, N4522V, Pratt & Whitney JT9D-7A, Transoceanic FlightBryan Swopes

China Airlines' Boeing 747SP, N45522V. Thi saircraft few as Dynasty 006, 18 February 1985. (Andrew Hunt) — China Airlines’ Boeing 747SP, N4522V. This aircraft few as Dynasty 006, 18 February 1985. (Andrew Hunt)

19 February 1985: At 10:16 a.m., Pacific Standard Time, while enroute from Taipei, Republic of China, to Los Angeles, California, China Airlines’ Flight 006 (call sign “Dynasty Six”), a Boeing 747SP-09, FAA registration N4522V, was cruising at 41,000 feet (12,497 meters), 300 nautical miles (556 kilometers) northwest of San Francisco, California. It had a crew of 23 with 251 passengers. The airliner had a flight crew of five under command of Captain Min-Yuan Ho, with a co-pilot and flight engineer, as well as a relief captain and flight engineer, due to the length of the trans-Pacific flight.

Captain Min-Yuan Ho, describing the incident to reporters at San Francisco Airport, 19 February 1985.

The Number 4 engine, the outboard engine on the airplane’s right wing, a Pratt & Whitney JT9D-7A turbofan, refused to respond with the other engines as the throttles were advanced, and it “hung” and remained at a low power level. It did not flame out, as the crew believed. The crew attempted restart procedures, however they did so incorrectly.

The airliner’s autopilot was engaged and the aircraft began to yaw and bank because of the asymmetric thrust. The copilot, First Officer Ju Yu Chang, used full opposite aileron to stop the roll, but neither pilot or copilot applied any rudder inputs to correct the yaw. (It was later determined that they believed, incorrectly, that the autopilot controlled rudder position.)

The airplane departed controlled flight, rolled over and dived. It lost 30,000 feet (9,144 meters) of altitude before the crew was able to recover, however the airplane was severely damaged, with bent wings, a damaged left aileron, lost parts of its elevators and horizontal stabilizers and damaged landing gear doors. It had experienced acceleration forces as high as 4.8 Gs as it descended through 30,552 feet (9,312 meters) and a peak 5.1 Gs at 19,083 feet (5,816 meters).

This illustration, based on the NTSB accident investigation, shows the various attitudes of China Airlines Flight 006 as it descended out of control, 19 February 1985. (Wikipedia)

Of the 287 persons on board, 24 were injured. Two were seriously hurt and the flight diverted to San Francisco. The 747SP was substantially damaged. It was nearly two years before repairs completed.

China Airlines’ Boeing 747SP-09 N4522V, photographed at Amsterdam, 16 June 1991. (Torsten Maiwald/Wikimedia)

The National Transportation Safety Board investigation made the following findings:

3.1 Findings

1. The flightcrew was properly certificated and qualified.

2. The changing airspeeds encountered by Flight 006 and the resultant compensating throttle adjustments were caused by wind speed variations.

3. The No. 4 engine did not flame out, but “hung” at about 1.0 EPR.

4. During his attempt to recover the No. 4 engine, the flight engineer did not close the bleed air valve switch before advancing the No. 4 throttle.

5. The other three engines did not lose thrust nor did they flame out.

6. The captain did not disengage the autopilot in a timely manner after thrust was lost on the No. 4 engine. The autopilot effectively masked the approaching onset of the loss of control of the airplane.

7. The captain was distracted from his flight monitoring duties by his participation with the flight engineer in the evaluation of the No. 4 engine’s malfunction.

8. With the exception of the loss of thrust on the No. 4 engine, no other airplane malfunction affected the performance of the airplane; the loss of thrust on the No. 4 engine did not contribute to the accident.

9. The captain was also distracted by his attempts to arrest the airplane’s decreasing airspeed, and this also contributed to his failure to detect the airplane’s increasing bank angle.

10. The lateral control deflections required to maintain level flight under conditions of thrust asymmetry and decreasing airspeed exceeded the limits of the autopilot’s lateral control authority, causing the airplane to roll and yaw to the right. The captain lost control of the airplane when, after disengaging the autopilot, he failed to make the proper flight control corrections to recover the airplane.

11. The damage to the airplane was a result of the acceleration forces and high airspeeds that occurred during the upset and recovery maneuvers.

3.2 Probable Cause

The National Transportation Safety Board determines that the probable cause of this accident was the captain’s preoccupation with an inflight malfunction and his failure to monitor properly the airplane’s flight instruments which resulted in his losing control of the airplane.

Contributing to the accident was the captain’s over-reliance on the autopilot after the loss of thrust on the No. 4 engine.

The captain had not slept during his previous rest period and his tiredness was considered a factor in this incident.

Damage to the tail surfaces of Boeing 747SP N4522V.

The Boeing 747SP (“Special Performance”) is a very long range variant of the 747-100 series airliners. It has a shorter fuselage and larger tail surface than the standard model. The weight savings allows it to carry more fuel for longer flights, and it is also faster. Boeing built 45 747SPs.

The 747SP is 184 feet, 9 inches (56.312 meters) long, with a wingspan of 195 feet, 8 inches (59.639 meters). It has an overall height of 65 feet, 10 inches (20.066 meters). It has a maximum takeoff weight of 670,000 pounds.

The airliner has a cruising speed of 0.88 Mach (616 miles per hour, or 991 kilometers per hour) and a maximum speed of 0.92 Mach (680 knots, 1,094 kilometers per hour). The service ceiling is 45,100 feet (13,746 meters) and the range is 7,650 miles (12,311 kilometers), carrying 276 passengers and baggage. The fuel capacity is 47,210 gallons. (178,709 liters).

Damaged horizontal stabilizer and elevators of Boeing 747SP-09 N4522V (NTSB)

Boeing 747 SP N4522V (serial number 22805, line number 564) made its first flight 10 June 1982. It was leased to China Airlines by the Wilmington Trust Company, 15 June 1982 and delivered 29 June 1982.

Following the Flight 006 incident, the airliner was repaired by Boeing and returned to service 25 April 1985. It was leased to Mandarin Airlines from 1 January 1997 to 31 December 1997, then placed in storage at Las Vegas, Nevada.

On 18 December 2001, N4522V was purchased by Global Peace Initiative Inc. The FAA suspended its operating certificate 18 July 2005 for lack of proper maintenance. The airplane has been stored at Tijuana International Airport (TIJ), just south of the U.S./Mexico border, since 16 December 2005.

The FAA registration of N4522V expired 31 December 2016.

Boeing 747SP 09 serial number 22805. The airliner’s U.S. registration expired 31 December 2016. (Global Peace Initiative)

Boeing 747SP 09 serial number 22805. The airliner’s U.S. registration expired 31 December 2016. The derelict airliner was photographed at Tijuana, 16 June 2019. (Jorge Perez)

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

February 18, 2025Aviation1, 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.

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.

17 February 1956

February 17, 2025Aviation183-1001, 55-2955, AIM-9B Sidewinder, Aircraft Accident, Clarence Leonard Johnson, First Flight, Fish Salmon, General Electric J79-GE-3B, General Electric M61 Vulcan, Herman Richard Salmon, John A. ("Jack") Simpson Jr., Kelly Johnson, Lockheed Aircraft Corporation, Lockheed YF-104A Starfighter, Test PilotBryan Swopes

Lockheed YF-104A, 55-2955. (AFFTC History Office)

17 February 1956: Test pilot Herman Richard (“Fish”) Salmon made the first flight of the Lockheed YF-104A service test prototype, Air Force serial number 55-2955 (Lockheed serial number 183-1001). This airplane, the first of seventeen pre-production YF-104As, incorporated many improvements over the XF-104 prototype, the most visible being a longer fuselage.

Lockheed test pilots Anthony W. (“Tony”) LeVier, on the left, and Herman R. (“Fish”) Salmon, circa 1957. An F-104 Starfighter is in the background. (Jet Pilot Overseas)

On 28 February 1956, YF-104A 55-2955 became the first aircraft to reach Mach 2 in level flight.

The YF-104A was later converted to the production standard and redesignated F-104A.

Lockheed XF-104 53-7786. (Lockheed-Martin)

Lockheed YF-104A Starfighter 55-2955 (183-1001), right profile. Note the increased length of the fuselage and revised air intakes, compared to the XF-104, above. Also, the XF-104’s nose gear retracts backward, while the YF-104A’s gear swings forward. (U.S. Air Force)

The Lockheed F-104A Starfighter is a single-place, single-engine, Mach 2 interceptor. It was designed by a team lead by the legendary Clarence L. “Kelly” Johnson. The F-104A is 54.77 feet (16.694 meters) long with a wingspan of 21.94 feet (6.687 meters) and overall height of 13.49 feet (4.112 meters). The total wing area is just 196.1 square feet (18.2 square meters). At 25% chord, the wings are swept aft 18° 6′. They have 0° angle of incidence and no twist. The airplane has a very pronounced -10° anhedral. An all-flying stabilator is placed at the top of the airplane’s vertical fin, creating a “T-tail” configuration.

The F-104A had an empty weight of 13,184 pounds (5,980.2 kilograms). The airplane’s gross weight varied from 19,600 pounds to 25,300 pounds, depending on the load of missiles and/or external fuel tanks.

Internal fuel capacity was 896 gallons (3,392 liters). With Sidewinder missiles, the F-104A could carry two external fuel tanks on underwing pylons, for an additional 400 gallons (1,514 liters). If no missiles were carried, two more tanks could be attached to the wing tips, adding another 330 gallons (1,249 liters) of fuel.

Lockheed F-104A Starfighter three-view illustration with dimensions. (Lockheed Martin)

The F-104A was powered by a single General Electric J79-GE-3B, -11A or -19 engine. The J79 is a single-spool, axial-flow, afterburning turbojet, which used a 17-stage compressor and 3-stage turbine. The J79GE-3B has a continuous power rating of 8,950 pounds of thrust (39.81 kilonewtons) at 7,460 r.p.m. Its Military Power rating is 9,600 pounds (42.70 kilonewtons) (30-minute limit), and 15,000 pounds (66.72 kilonewtons) with afterburner (5-minute limit). The engine is 17 feet, 3.2 inches (5.263 meters) long, 2 feet, 8.6 inches (0.828 meters) in diameter, and weighs 3,225 pounds (1,463 kilograms).

Lockheed F-104A-5-LO Starfighter 56-742, with a General Electric J79 turbojet engine, circa 1957–59. (U.S. Air Force)

The F-104A had a maximum speed of 1,150 knots (1,323 miles per hour/2,130 kilometers per hour) at 35,000 feet (10,668 meters). The Starfighter’s initial rate of climb was 60,395 feet per minute (306.8 meters per second) and its service ceiling was 59,600 feet (18,166 meters).

The Lockheed F-104 was armed with an electrically-powered General Electric T-171E-3 (later designated M61) Vulcan 6-barrel rotary cannon, or “Gatling Gun.” The technician has a belt of linked 20 mm cannon shells. (SDASM)

Armament was one General Electric M61 Vulcan six-barreled revolving cannon with 725 rounds of 20 mm ammunition, firing at a rate of 4,000 rounds per minute. An AIM-9B Sidewinder infrared-homing air-to-air missile could be carried on each wing tip.

Lockheed YF-104A 55-2955 with landing gear retracting. (Lockheed Martin via International F-104 Society)

Lockheed built 153 of the F-104A Starfighter initial production version. A total of 2,578 F-104s of all variants were produced by Lockheed and its licensees, Canadair, Fiat, Fokker, MBB, Messerschmitt, Mitsubishi and SABCA. By 1969, the F-104A had been retired from service. The last Starfighter, an Aeritalia-built F-104S ASA/M of the Aeronautica Militare Italiana, was retired in October 2004.

While conducting flame-out tests in 55-2955, 25 April 1957, Lockheed engineering test pilot John A. (“Jack”) Simpson, Jr., made a hard landing at Air Force Plant 42, Palmdale, California, about 22 miles (35 kilometers) southwest of Edwards Air Force Base. After a bounce, the landing gear collapsed, and the Starfighter skidded off the runway. 55-2955, nick-named Apple Knocker, was damaged beyond repair. “Suitcase” Simpson was not hurt.

Lockheed F-104A 55-2955 was damaged beyond repair, 25 April 1967. (U.S. Air Force photograph via International F-104 Society)

15 February 1961, 09:05 UTC

February 15, 2025Aviation17624, Aircraft Accident, Boeing 707-329 Intercontinental, BRU, Brussels-Zaventem Airport, IDL, Idlewild Airport, Jean Roy, Laurence Owen, Laurie Owen, Ludovic Marie Antoine Lambrechts, OO-SJB, SABENA Flight SN548, Societé Anonyme Belge d'Exploitation de la Navigation Aérienne, United States Figure Skating AssociationBryan Swopes

Boeing 707-329 OO-SJB, Sabena Flight 548. (© Guy Van de Merckt)

Commandant de Bord Ludovic Marie Antoine Lambrechts, Officier de l’Ordre del Couronne, Chevalier de l’Ordre de Leopold. (1917–1961)

15 February 1961, 09:05 UTC: This Boeing 707-329 airliner, registration OO-SJB, under the command of Captain Ludovic Marie Antoine Lambrechts and Captain Jean Roy, was enroute from Idlewild Airport, New York (IDL) to Brussels-Zaventem Airport (BRU) as SABENA Flight SN548, when three miles (4.8 kilometers) short of the runway at an altitude of 900 feet (274 meters), it pulled up, retracted its landing gear and accelerated.

The airliner made three 360° circles, with the angle of bank steadily increasing to 90°. The 707’s wings then leveled, followed by an abrupt pitch up. OO-SJB spiraled into a nose-down dive and crashed into an open field 1.9 miles (3 kilometers) northeast of Brussels and all 61 passengers and 11 crew members and 1 person on the ground were killed, including the entire U.S. Figure Skating Association team, their families, coaches, judges and officials.

“FIGURE 3: SABENA, Boeing 707, OO-SJB, accident 2 km NE of threshold of runway 20 at Brussels National Airport, Belgium, 15 February 1961” —ICAO Circular 69-AN/61, Page 58

Wreckage of Sabena Flight 548, 15 February 1961. — Wreckage of SABENA Flight SN548, Brussels, Belgium, 15 February 1961.

The cause of the crash was never determined but is suspected to be a mechanical failure in the flight control system:

Probable Cause

Having carried out all possible reasonable investigations, the Commission concluded that the cause of the accident had to be looked for in the material failure of the flying controls.

However, while it was possible to advance certain hypotheses regarding the possible causes, they could not be considered entirely satisfactory. Only the material failure of two systems could lead to a complete explanation, but left the way open to an arbitrary choice because there was not sufficient evidence to corroborate it.

—ICAO Circular 69-AN/61, Page 55, Column 2

The Federal Aviation Administration’s comments were included in the accident report:

“Of the several hypotheses evolving from findings in the accident report, we believe the most plausible to be that concerned with a malfunction of the stabilizer adjusting mechanism permitting the stabilizer to run to the 10.5-degree nose-up position. If such a malfunction occurred and the split flaps and spoilers procedure (inboard spoilers and outboard flaps extended) not employed, the only means to prevent the aircraft from pitching up into a stall would be to apply full forward column and enter a turn in either direction.”

“It is apparent from the recorded impact positions that the split flaps and spoilers technique was not used. The wing flaps were found in the up position and had the inboard spoilers been extended both would have been up at impact and the speed brake handle would not have been in the neutral position as found.”

—ICAO Circular 69-AN/61, Page 56, Column 2

Societé Anonyme Belge d’Exploitation de la Navigation Aérienne (SABENA) was the national airline of Belgium. It was based at Brussels and operated from 1923 to 2001.

The United States Figure Skating Association team, boarding SABENA Flight SN548 at Idlewild Airport, New York, 14 February 1961. From left in front row are: Deane McMinn, Laurence Rochon Owen, Steffi Westerfeld and Rhode Lee Michelson. From left on the bottom: Douglas Ramsay, Gregory Kelley, Bradley Lord, Maribel Y. Owen, Dudley Richards, William Hickox, Ray Hadley Jr., Laurie Hickox, Larry Pierce, Ila Ray Hadley, Roger Campbell, Diane Sherbloom, Dona Lee Carrier, and Robert and Patricia Dineen. (U.S.F.S.A.)

This February 13, 1961 edition of Sports Illustrated was found in the burned-out wreckage of SABENA SN548. U.S.F.S.A. figure skater Laurence Rochon Owen’s photograph is on the cover. The 16-year-old skater is second from the left in the team photograph, above.

SABENA Flight SN548 was a Boeing 707-329 Intercontinental, OO-SJB, Boeing serial number 17624. It made its first test flight 13 December 1959 at Renton, Washington, and was delivered to SABENA in January 1960. At the time of the accident, it had just 3,038 total flight hours (TTAF). The airplane had undergone a Type II overhaul just 37 hours before the crash. ¹

The Boeing 707 was a jet airliner which had been developed from the Model 367–80 prototype, the “Dash Eighty.” It 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 707-329 Intercontinental is 152 feet, 11 inches (46.611 meters) long with a wing span of 145 feet, 9 inches (44.425 meters). The top of the vertical fin stands 42 feet, 5 inches (12.928 meters) high. The wing is considerably different than on the original 707-120 series, with increased length, different flaps and spoilers, and the engines are mounted further outboard. The vertical fin is taller, the horizontal tail plane has increased span, and there is a ventral fin for improved longitudinal stability. The 707 pre-dated the ”wide-body” airliners, having a fuselage width of 12 feet, 4 inches (3.759 meters).

SABENA Boeing 707-329 OO-SJD, a sistership of the accident aircraft, at Nice Côte d’Azur Airport, France. (Alain Durand/Wikipedia)

The the 707-320 International-series had an operating empty weight of 142,600 pounds (64,682 kilograms). Its maximum take off weight (MTOW) was 312,000 pounds (141,521 kilograms). When OO-SJB departed New York, its total weight was 119,500 kilograms (263,452 pounds), well below MTOW. It carried 50,000 kilograms (110,231 pounds) of JP-1 fuel.

OO-SJB was powered by four Pratt & Whitney Turbo Wasp JT4A engines. These were two-spool, axial-flow turbojet engine with a 15-stage compressor (8 low-, 7 high-pressure stages) and 3-stage turbine (1 high- and 2 low-pressure stages). The –12 was rated at 14,900 pounds of thrust (66.279 kilonewtons), maximum continuous power, and 17,500 pounds of thrust (77.844 kilonewtons) at 9,355 r.p.m. (N₂) for takeoff. The engine was 12 feet, 0.1 inches (3.660 meters) long, 3 feet, 6.5 inches (1.080 meters) in diameter, and weighed 4,895 pounds (2,220 kilograms).

The 707-329 had a maximum operating speed (M_MO) of 0.887 Mach above 25,000 feet (7,620 meters). At 24,900 feet (7,590 meters), its maximum indicated airspeed (V_MO) was 378 knots (435 miles per hour/700 kilometers per hour). At MTOW, the 707-329 required 10,840 feet (3,304 meters) of runway for takeoff. It had a range of 4,298 miles (6,917 kilometers).

The Boeing 707 was in production from 1958 to 1979. 1,010 were built.

The cover of the 13 February 1961 edition of Sports Illustrated. (SI) — The cover of the 13 February 1961 edition of *Sports Illustrated*. (SI)

According to the accident investigation report, following this overhaul, which took place from 11 January to 9 February 1961,

1) The pilot noted that during the first test flight on 9 February 1962 the trim button had to be pushed harder than normal. A second test flight was made to confirm the fault, after which the pilot noted “abnormal response of the stabilizer particularly after trimming nose down; slight nose up impulses give no result.”

2) The second incident was observed during the same flight. The pilot noted: “At the beginning of the flight there was a strong tendency of the aircraft to roll to the right. In level flight, the two left wing spoilers are 1 inch out.

“After descent, speed brakes out, at the moment of their retraction there was a marked roll to the right – it did not recur afterwards.

“At the end of the flight, the tendency to roll to the right was considerably diminished.”

—ICAO Circular 69-AN/61, Page 44, Column 2

In response to the stabilzer trim concern, maintenance replaced the stabilizer trim motor. It functioned normally during ground tests. As to the roll issue, an inspection following the flight did not reveal anything abnormal.

13 February 1950

February 13, 2025Aviation1, 2, 3, 44-92075, 5, Aircraft Accident, B-36B-15-CF, Bomb Mark 4, Broken Arrow, Captain Harold L. Barry, Consolidate-Vultee Aircraft Corporation, Consolidated-Vultee B-36B Peacemaker, Harold Leslie Barry, Kispiox Valley, Los Alamos National Laboratory, Pratt & Whitney R-4360-41, Princess Royal IslandBryan Swopes

A flight of two Consolidated-Vultee B-36B Peacemaker strategic bombers. (LIFE Magazine)

13 February 1950: Two Consolidated-Vultee B-36B Peacemaker long-range strategic bombers of the 436th Bombardment Squadron (Heavy), 7th Bombardment Wing (Heavy), Strategic Air Command, departed Eielson Air Force Base (EIL), Fairbanks, Alaska, at 4:27 p.m., Alaska Standard Time (01:27 UTC), on a planned 24-hour nuclear strike training mission.

B-36B-15-CF 44-92075 was under the command of Captain Harold Leslie Barry, United States Air Force.¹ There were a total of seventeen men on board.

Also on board was a Mark 4 nuclear bomb.

The B-36s were flown to Alaska from Carswell Air Force Base, Fort Worth, Texas, by another crew. The surface air temperature at Eielson was -40 °F. (-40 °C.), so cold that if the bomber’s engines were shut down, they could not be restarted. Crews were exchanged and the airplane was serviced prior to takeoff for the training mission. In addition to the flight crew of fifteen, a Bomb Commander and a Weaponeer were aboard.

Consolidated-Vultee B-36 44-92027. (LIFE Magazine)

After departure, 44-92075 began the long climb toward 40,000 feet (12,192 meters). The flight proceeded along the Pacific Coast of North America toward the practice target city of San Francisco, California. The weather was poor and the bomber began to accumulate ice on the airframe and propellers.

About seven hours into the mission, three of the six radial engines began to lose power due to intake icing. Then the #1 engine, outboard on the left wing, caught fire and was shut down. A few minutes later, the #2 engine, the center position on the left wing, also caught fire and was shut down. The #3 engine lost power and its propeller was feathered to reduce drag. The bomber was now flying on only three engines, all on the right wing, and was losing altitude. When the #5 engine, center on the right wing, caught fire, the bomber had to be abandoned. It was decided to jettison the atomic bomb into the Pacific Ocean.

Consolidated-Vultee B-36B-1-CF Peacemaker of the 7th Bombardment Wing. (U.S. Air Force)

The Mark 4 did not have the plutonium “pit” installed, so a nuclear detonation was not possible. The conventional explosives would go off at a pre-set altitude and destroy the bomb and its components. This was a security measure to prevent a complete bomb from being recovered.

The bomb was released at 9,000 feet (2,743 meters), north-northwest of Princess Royal Island, off the northwest coast of British Columbia, Canada. It was fused to detonate 1,400 feet (427 meters) above the surface, and crewmen reported seeing a large explosion.

Consolidated-Vultee B-36B-1-CF Peacemaker, 44-92033, of the 7th Bombardment Wing (Heavy). This bomber is similar to 44-92075. (U.S. Air Force)

Flying over Princess Royal Island, Captain Barry ordered the crew to abandon the aircraft. He placed the B-36 on autopilot. Barry was the last man to leave 44-92075. Descending in his parachute, he saw the bomber circle the island once before being lost from sight.

Twelve of the crew survived. Five were missing and it is presumed that they landed in the water. Under the conditions, they could have survived only a short time. The survivors had all been rescued by 16 February.

It was assumed that 44-92075 had gone down in the Pacific Ocean.

Approximate path of B-36B 44-92075, 13 February 1950. (Royal Aviation Museum of British Columbia)

On 20 August 1953, a Royal Canadian Air Force airplane discovered the wreck of the missing B-36 on a mountain on the east side of Kispiox Valley, near the confluence of the Kispiox and Skeena Rivers in northern British Columbia.

The U.S. Air Force made several attempts to reach the crash site, but it wasn’t until August 1954 that they succeeded. After recovering sensitive equipment from the wreckage, the bomber was destroyed by explosives.

The Mark 4 bomb was designed by the Los Alamos National Laboratory (LANL). It was a development of the World War II implosion-type Mark 3 “Fat Man.” The bomb was 10 feet, 8 inches (3.351 meters) long with a maximum diameter of 5 feet, 0 inches (1.524 meters). Its weight is estimated at 10,800–10,900 pounds (4,899–4,944 kilograms).

The core of the bomb was a spherical composite of plutonium and highly-enriched uranium. This was surrounded by approximately 5,500 pounds (2,495 kilograms) of high explosive “lenses”—very complex-shaped charges designed to focus the explosive force inward in a very precise manner. When detonated, the high explosive “imploded” the core, crushing it into a smaller, much more dense mass. This achieved a “critical mass” and a fission chain reaction resulted.

The Mark 4 was tested during Operation Ranger at the Nevada Test Site, Frenchman Flat, Nevada, between 27 January and 6 February 1951. Five bombs were dropped from a Boeing B-50 Superfortress of the 4925th Special Weapons Group from Kirtland Air Force Base in New Mexico. The first four bombs were dropped from a height of 19,700 feet (6,005 meters) above ground level (AGL) and detonated at 1,060–1,100 feet (323–335 meters) AGL. Shot Fox was dropped from 29,700 feet (9,053 meters) AGL and detonated at 1,435 feet (437 meters) AGL. (Ground level at Frenchman Flat is 3,140 feet (957 meters) above Sea Level).

Operation Ranger, Shot Able, 5:45 a.m., 27 January 1951. Mark 4 bomb with Type D pit, 1,060 foot (323 meters) air burst. Yield, 1 kiloton. This was the first nuclear test in the continental United States since Trinity, 16 July 1945.

The Mark 4 was produced with explosive yields ranging from 1 to 31 kilotons. 550 were built.

Consolidated-Vultee B-36B-15-CF Peacemaker 44-92075 was completed at Air Force Plant 4, Fort Worth, Texas, on 31 July 1949. It had been flown a total of 185 hours, 25 minutes.

The B-36B is 162 feet, 1 inch (49.403 meters) long with a wingspan of 230 feet (70.104 meters) and overall height of 46 feet, 8 inches (14.224 meters). The wings’ leading edges were swept aft 15° 5′ 39″. Their angle of incidence was 3°, with -2° twist and 2° dihedral. The empty weight is 137,165 pounds (62,217 kilograms) and the maximum takeoff weight was 326,000 pounds (147,871 kilograms).

With a wing area of 4,772 square feet (443 square meters) and 21,000 horsepower, the B-36 could fly far higher than any jet fighter of the early 1950s.

A Pratt & Whitney R-4360-41 Wasp Major aircraft engine on display at the National Museum of the United States Air Force. This engine weighs 3,404 pounds (1,544 kilograms). Wikipedia — A Pratt & Whitney Wasp Major B4 (R-4360-41) aircraft engine on display at the National Museum of the United States Air Force. This engine is 9 feet, 1¾-inch (2.788 meters) long and 4 feet, 6 inches (1.372 meters) in diameter. It weighs 3,567 pounds (1,618 kilograms). Wikipedia

The B-36B was powered by six air-cooled, supercharged and turbocharged 4,362.49 cubic-inch-displacement (71.488 liter) Pratt & Whitney Wasp Major B4 (R-4360-41) four-row, 28-cylinder radial engines placed inside the wings in a pusher configuration. These had a compression ratio of 6.7:1 and required 115/145 aviation gasoline. Each engine was equipped with two General Electric BH-1 turbochargers. The R-4360-41 had a Normal Power rating of 2,650 horsepower at 2,550 r.p.m. Its Takeoff/Military Power rating was 3,500 horsepower at 2,700 r.p.m., with water/alcohol injection. The engines turned three-bladed Curtiss Electric constant-speed, reversible propellers with a diameter of 19 feet, 0 inches (5.791 meters) through a 0.375:1 gear reduction. The R-4360-41 is 9 feet, 1.75 inches (2.788 meters) long, 4 feet, 6.00 inches (1.372 meters) in diameter, and weighs 3,567 pounds (1,618 kilograms).

The B-36B Peacemaker had a cruise speed of 193 knots (222 miles per hour/357 kilometers per hour) and a maximum speed of 338 knots (389 miles per hour/626 kilometers per hour) at 35,500 feet (10,820 meters). The service ceiling was 43,700 feet (13,320 meters) and its combat radius was 3,710 nautical miles (4,269 statute miles/6,871 kilometers). The maximum ferry range was 8,478 nautical miles (9,756 statute miles/15,709 kilometers).

The B-36 was defended by sixteen M24A-1 20 mm automatic cannons. Six retractable gun turrets each each had a pair of 20 mm cannon, with 600 rounds of ammunition per gun (400 r.p.g.for the nose guns). These turrets were remotely operated by gunners using optical sights. Two optically-sighted 20 mm guns were in the nose, and two more were in a tail turret, also remotely operated and aimed by radar.

In this photograph, two of the B-36's retractable gun turrets are visibile behind the cockpit, as well as the nose gun turret. (Unattributed) — In this photograph, two of the B-36’s retractable gun turrets are visible behind the cockpit, as well as the nose gun turret. The plexiglas “blister” just ahead and below the dorsal turrets is a gunner’s sighting station. The bomb bay doors are open. (Unattributed)

The B-36 was designed during World War II and nuclear weapons were unknown to the Consolidate-Vultee Aircraft Corporation engineers. The bomber was built to carry up to 86,000 pounds (39,009 kilograms) of conventional bombs in the four-section bomb bay. It could carry two 43,600 pound (19,777 kilogram) T-12 Cloudmakers, a conventional explosive earth-penetrating bomb. When armed with nuclear weapons, the B-36 could carry several Mk.15 thermonuclear bombs. By combining the bomb bays, one Mk.17 25-megaton thermonuclear bomb could be carried.

Between 1946 and 1954, 384 B-36 Peacemakers were built by Convair. 73 of these were B-36Bs, the last of which were delivered to the Air Force in September 1950. By 1952, 64 B-36Bs had been upgraded to B-36Ds.

The B-36 Peacemaker was never used in combat. Only four still exist.

¹ Captain Barry was killed along with other 11 crewmen, 27 April 1951, when the B-36D-25-CF on which he was acting as co-pilot, 49-2658, crashed following a mid-air collision with a North American F-51-25-NT Mustang, 44-84973, 50 miles (80 kilometers) northeast of Oklahoma, City, Oklahoma, U.S.A. The Mustang’s pilot was also killed.

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