Tag Archives: LAX

26 February 1955

North American Aviation production test pilot George Franklin Smith with a North American F-100A Super Sabre (NASM)

26 February 1955: Although it was his day off, North American Aviation production test pilot George Franklin Smith stopped by the office at Los Angeles Airport (today, known as Los Angeles International airport, or simply “LAX”, its international airport identifier). The company’s flight  dispatcher told him that a brand-new F-100A-20-NA Super Sabre, serial number 53-1659, was sitting on the flight line and needed to be test flown before being turned over to the Air Force.

North American Aviation production test pilot George F. Smith (left) walks away from an F-100 Super Sabre. (Photograph courtesy of Neil Corbett, Test and Research Pilots, Flight Test Engineeers)
North American Aviation production test pilot George F. Smith (left) walks away from an F-100 Super Sabre. (Photograph courtesy of Neil Corbett, Test and Research Pilots, Flight Test Engineeers)

Smith was happy to take the flight. He departed LAX in full afterburner and headed off shore, climbing to 35,000 feet (10,668 meters) over the Pacific Ocean to start the test sequence.

A North American F-100A-1-NA Super Sabre, 52-5757 (the second production airplane) takes off at Los Angeles International Airport. (This airplane, flown by NAA test pilot Bob Hoover, crashed east of Palmdale, California, 7 July 1955, when he could not recover from a flat spin. Hoover safely ejected but the Super Sabre was destroyed.) (North American Aviation, Inc.)

But it was quickly apparent that something was wrong: The flight controls were heavy, and then there was a hydraulic system failure that caused the Super Sabre pitch down into a dive. Smith couldn’t pull it out of the dive and the airplane’s speed rapidly increased, eventually passing Mach 1.

Smith was unable to regain control of the F-100. He had no choice but to bail out. As he ejected, Smith read the instruments: the Mach meter indicated Mach 1.05—785 miles per hour (1,263 kilometers per hour)—and the altitude was only 6,500 feet (1,981 meters).

George F. Smith recovering in hospital after his supersonic ejection. (Getty Images)
Smith recovering in hospital after his supersonic ejection. (Getty Images)

The force of the wind blast hitting him as he came out of the cockpit knocked him unconscious. Estimates are that he was subjected to a 40 G deceleration. His parachute opened automatically and he came down approximately one-half mile off Laguna Beach. Fortunately he hit the water very close to a fishing boat crewed by a former U.S. Navy rescue expert.

The F-100 dived into the Pacific Ocean approximately ¼-mile (0.4 kilometers) offshore between Dana Point and Laguna Beach.

George Smith was unconscious for six days, and when he awoke he was blind in both eyes. After four surgeries and seven months in the hospital, he recovered from his supersonic ejection and returned to flight status.

North American Aviation, Inc. F-100A-20-NA Supre Sabre 53-1646. This fighter is from the same production block as the Super Sabre flown by George F. Smith, 53-1659, 26 February 1955. (Unattributed)

George F. Smith appears in this brief U.S. Air Force informational film:

The North American Aviation F-100 Super Sabre was designed as a supersonic day fighter. Initially intended as an improved F-86D and F-86E, it soon developed into an almost completely new airplane. The fuselage incorporated the “area rule,” a narrowing in the fuselage width at the wings to increase transonic performance, similar to the Convair F-102A.

The Super Sabre had a 49° 2′ sweep to the leading edges of the wings and horizontal stabilizer. The ailerons were placed inboard on the wings and there were no flaps, resulting in a high stall speed in landing configuration. The horizontal stabilizer was moved to the bottom of the fuselage to keep it out of the turbulence created by the wings at high angles of attack. The F-100A had longer wings and a distinctively shorter vertical fin than the YF-100A. The upper segment of the vertical fin was swept 49° 43′.

North American Aviation YF-100A Super Sabre 52-5754 lands on the dry lake at Edwards Air Force Base, California. (North American Aviation, Inc.)

There were two service test prototypes, designated YF-100A, followed by the production F-100A series. The first ten production aircraft (all of the Block 1 variants) were used in the flight testing program.

The F-100A Super Sabre was 47 feet, 1¼ inches (14.357 meters) long with a wingspan of 36 feet, 6 inches (11.125 meters). With the shorter vertical fin than the YF-100A, the initial F-100As had an overall height of 13 feet, 4 inches (4.064 meters), 11 inches (27.9 centimeters) less than the YF-100A.

The F-100A had an empty weight of 18,135 pounds (8,226 kilograms), and gross weight of 28,899 pounds (13,108 kilograms). Maximum takeoff weight was 35,600 pounds (16,148 kilograms). It had an internal fuel capacity of 755 gallons (2,858 liters) and could carry two 275 gallon (1,041 liter) external fuel tanks.

Following North American Aviation test pilot George Welch’s fatal accident, 12 October 1954, NACA designed a new vertical fin for the F-100A. It was taller but also had a longer chord. This resulted in a 10% increase in area. (NASA E-1573)

The early F-100As were powered by a Pratt & Whitney Turbo Wasp J57-P-7 afterburning turbojet engine. It was rated at 9,700 pounds of thrust (43.148 kilonewtons) for takeoff, and 14,800 pounds (65.834 kilonewtons) with afterburner. Later production aircraft used a J57-P-39 engine. The J57 was a two-spool axial flow turbojet which had a 16-stage compressor, and a 3-stage turbine. (Both had high- and low-pressure stages.) The engine was 15 feet, 3.5 inches (4.661 meters) long, 3 feet, 5.0 inches (1.041 meters) in diameter, and weighed 4,390 pounds (1,991 kilograms).

Test Pilot A. Scott Crossfield flew this F-100A-5-NA, 52-5778, in flight testing at the NACA High Speed Flight Station, October–December 1954. (NASA)

The Super Sabre was the first U.S. Air Force fighter capable of supersonic speed in level flight. It could reach 760 miles per hour (1,223 kilometers) at Sea Level. (Mach 1 is 761.1 miles per hour, 1,224.9 kilometers per hour, under standard atmospheric conditions.) Its maximum speed was 852 miles per hour (1,371 kilometers per hour) at 35,000 feet (10,668 meters). The service ceiling was 44,900 feet (13,686 meters). Maximum range with external fuel was 1,489 miles (2,396 kilometers).

The F-100 was armed with four M-39 20 mm autocannons, capable of firing at a rate of 1,500 rounds per minute. The ammunition capacity of the F-100 was 200 rounds per gun.

North American Aviation built 199 F-100A Super Sabres at its Inglewood, California, plant before production shifted to the F-100C fighter bomber variant. Approximately 25% of all F-100As were lost in accidents.

This is the fifth production F-100A-1-NA Super Sabre, 52-5760, in flight southeast of San Bernardino, California. In this photograph, FW-760 has the taller vertical fin that was designed to improve the Super Sabre’s controllability. (U.S. Air Force)

© 2019, Bryan R. Swopes

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14 August 1968

Sikorsky S-61L N300Y, Los Angeles Airways, at Disneyland Heliport, Anaheim, California. (Robert Boser)
Sikorsky S-61L N300Y, Los Angeles Airways, at Disneyland Heliport, Anaheim, California. (Robert Boser)

14 August 1968: At 10:28:15 a.m., Pacific Daylight Time, Los Angeles Airways Flight 417, a Sikorsky S-61L helicopter, departed Los Angles International Airport (LAX) on a regularly-scheduled passenger flight to Disneyland, Anaheim, California. On board were a crew of three and eighteen passengers. The aircraft commander, Captain Kenneth L. Waggoner, held an Airline Transport Pilot certificate and was type-rated in the Sikorsky S-55, S-58 and S-61L. He had a total of 5,877:23 flight hours, with 4,300:27 hours in the S-61L. Co-pilot F. Charles Fracker, Jr. had 1,661:18 flight hours, of which 634:18 were in the S-61L. Flight Attendant James A. Black had been employed with LAA for nearly ten years.

At approximately 10:35 a.m., while flying at an estimated altitude of 1,200–1,500 feet (370–460 meters) above the ground, one of the helicopter’s five main rotor blades separated from the aircraft which immediately went out of control, started to break up, and crashed in a recreational park in Compton. All twenty-one persons on board, including the 13-year-old grandson of the airlines’ founder and CEO, were killed.

The Sikorsky S-61 was registered N300Y.  It had been the prototype S-61L, serial number 61031. Los Angeles Airways was the first civil operator of the S-61, purchasing them at a cost of $650,000 each. As of the morning of 14 August 1968, 61031 had accumulated a total of 11,863.64 hours flight time on the airframe (TTAF). It flew an estimated 3.17 hours on the morning of the accident.

The Sikorsky S-61L was a civil variant of the United States Navy HSS-2 Sea King, and was the first helicopter specifically built for airline use. The prototype, N300Y, first flew 2 November 1961. It is a large twin-engine helicopter with a single main rotor/tail rotor configuration. Although HSS-2 fuselage is designed to allow landing on water, the S-61L is not amphibious, having standard fixed landing gear rather than the sponsons of the HSS-2 (and civil S-61N). The S-61L fuselage is 4 feet, 2 inches (1.270 meters) longer than that of the HSS-2. The S-61L is 72 feet, 7 inches (22.123 meters) long and 16 feet, 10 inches (5.131 meters) high, with rotors turning.

The main rotor has five blades and a diameter of 62 feet (18.898 meters). Each blade has a chord of 1 foot, 6.25 inches (0.464 meters). The tail rotor also has five blades and a diameter of 10 feet, 4 inches (3.149 meters). They each have a chord of 7–11/32 inches (0.187 meters). At 100% r.p.m., the main rotor turns 203 r.p.m. and the tail rotor, 1,244 r.p.m. The main rotor turns counter-clockwise, as seen from above. (The advancing blade is on the helicopter’s right side.) The tail rotor turns clockwise, as seen from the left side. (The advancing blade is below.)

The S-61L was powered by two General Electric CT58-140-1 turboshaft engines, each of which was rated for 1,400 shaft horsepower for takeoff and maximum power of 1,500 shaft horsepower for 2½ minutes. The main transmission was rated for 2,300 horsepower, maximum.

The S-61 has a cruise speed of  166 miles per hour (267 kilometers per hour).  The service ceiling is 12,500 feet (3,810 meters). 61031 had a maximum takeoff weight (MTOW) of 19,000 pounds (8,618.3 kilograms).

Between 1958 and 1980, Sikorsky built 794 S-61 series helicopters. 13 were S-61Ls.

The National Transportation Safety Board investigation found that most of the helicopter was contained with a small area of Leuders Park. One main rotor blade, however, was located approximately 0.25 miles (0.40 kilometers) west of the main wreckage. This blade is referred to as the “yellow” blade. (The main rotor blades marked with colored paint for simplicity, red, black, white, yellow, and blue.) Analysis found that this blade’s spindle, where it attached to the main rotor hub assembly, had failed due to a fatigue fracture. It was believed that the fracture began in an area of substandard hardness which was present in the original ingot from which the part was forged, and that inadequate shot-peening of the part during the overhaul process further weakened the spindle.

Diagram of fractured main rotor spindle. (NTSB)
Diagram of fractured main rotor spindle. (NTSB)

Los Angeles Airways had experienced a similar accident only three months earlier which had resulted in the deaths of all 23 persons on board. (Flight 841, 22 May 1968). L.A. Airways never recovered from these accidents and ceased all operations by 1971.

© 2016, Bryan R. Swopes

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