Tag Archives: Aircraft Accident

15 November 1967

Major Michael J. Adams, United States Air Force, with an X-15 hypersonic research rocketplane on Rogers Dry Lake. (NASA)
Major Michael J. Adams, United States Air Force, with a North American Aviation X-15 hypersonic research rocketplane, 56-6670, on Rogers Dry Lake, after his third flight in the program, 22 March 1967. (NASA)

15 November 1967: Major Michael James Adams, United States Air Force, was killed in the crash of the number three North American Aviation X-15 hypersonic research rocketplane, 56-6672.

Flight 191 of the X-15 program was Mike Adams’ seventh flight in the rocketplane. It was the 56-6672’s 65th flight. The flight plan called for 79 seconds of engine burn, accelerating the X-15 to Mach 5.10 while climbing to 250,000 feet (76,200 meters). Adams’ wife, Freida, and his mother, Georgia Adams, were visiting in the NASA control room at Edwards Air Force Base.

Balls 8, the Boeing NB-52B Stratofortress, 52-008, flown by Colonel Joe Cotton, took off from Edwards at 9:12 a.m., carrying -672 on a pylon under its right wing, and headed north toward the drop point over Delamar Dry Lake in Nevada. The drop ship climbed to the launch altitude of 45,000 feet (13,716 meters).

The X-15 launch was delayed while waiting for the Lockheed C-130 Hercules rescue aircraft to arrive on station. This required Adams to reset the Honeywell MH-96 Automatic Flight Control System to compensate for the changing position of the sun in the sky.

X-15A-3
North American Aviation X-15A-3 56-6672 immediately after launch over Delamar Lake, Nevada. Date unknown. (U.S. Air Force)

56-6672 was launched by Balls 8 at 10:30:07.4 a.m., Pacific Standard Time. As it dropped clear of the bomber, the rocketplane rolled 20° to the right, a normal reaction. Within one second, Mike Adams had started the XLR99-RM-1 rocket engine while bringing the wings level. The engine ignited within one-half second and was up to its full 57,000 pounds of thrust (253.549 kilonewtons) one second later. The engine ran for 82.3 seconds, 3.3 seconds longer than planned, causing the X-15 to reach Mach 5.20 (3,617 miles per hour/5,821 kilometers per hour) and to overshoot the planned altitude to peak at 266,000 feet (81,077 meters).

A North American Aviation X-15 hypersonic research rocketplane leaves a contrail as it climbs toward the edge of space. (NASA)
A North American Aviation X-15 hypersonic research rocketplane leaves a contrail as it climbs toward the edge of space. (NASA)

With the X-15 climbing through 140,000 feet (42,672 meters), the Inertial Flight Data System computer malfunctioned. Adams radioed ground controllers that the system’s malfunction lights had come on.

The flight plan called for a wing-rocking maneuver at peak altitude so that a camera on board could scan from horizon to horizon. During this maneuver, the Reaction Control System thrusters did not respond properly to Adams’ control inputs. The X-15 began to yaw to the right.

As it reached its peak altitude, 56-6672 yawed 15° to the left. Going over the top, the nose yawed right, then went to the left again. By the time the aircraft has descended to 230,000 feet (70,104 meters), it had pitched 40° nose up and yawed 90° to the right its flight path. The X-15 was also rolling at 20° per second. The rocketplane went into a spin at Mach 5.

10:33:37 Chase 1: “Dampers still on, Mike?”

10:33:39 Adams: “Yeah, and it seems squirrelly.”

10:34:02 Adams: “I’m in a spin, Pete.” [Major William J. “Pete” Knight, another X-15 pilot, was the flight controller, NASA 1]

10:34:05 NASA 1: “Let’s get your experiment in and the cameras on.”

10:34:13 NASA 1: “Let’s watch your theta, Mike.”

10:34:16 Adams: “I’m in a spin.”

10:34:18 NASA 1: “Say again.”

10:34:19 Adams: “I’m in a spin.”

Adams fought to recover, and at 118,000 feet (35,967 meters) came out of the spin, but he was in an inverted 45° dive at Mach 4.7. The X-15’s MH-96 Automatic Flight Control System entered a series of diverging oscillations in the pitch and roll axes, with accelerations up to 15 gs. Dynamic pressures on the airframe rapidly increased from 200 pounds per square foot (9.576 kilopascals) to 1,300 pounds per square foot (62.244 kilopascals).

At 62,000 feet (18,898 meters), still at Mach 3.93, the aircraft structure failed and it broke apart.

10:34:59 X-15 telemetry failed. Last data indicated it was oscillating +/- 13 g. Radar altitude was 62,000 feet (18,898 meters). The aircraft was descending at 2,500 feet per second (762 meters per second) and broke into many pieces at this time.

10:35:42 NASA 1: “Chase 4, do you have anything on him?”

10:35:44 Chase 4: “Chase 4, negative.”

10:35:47 NASA 1: “OK, Mike, do you read?”

10:35:52 Chase 4: “Pete, I got dust on the lake down there.”

North American Aviation X-15A-3 56-6672 crashed in a remote area, approximately 5½ miles (9 kilometers) north-northeast of Randsburg, California, a small village along U.S. Highway 395.

Major Michael James Adams was killed. This was the only pilot fatality of the entire 199-flight X-15 program.

North American Aviation X-15A 56-6672 on Rogers Dry Lake after a flight. (NASA)
North American Aviation X-15A-3 56-6672 on Rogers Dry Lake. (NASA)

An investigation by NASA’s Engineering and Safety Center determined that,

“. . . the root cause of the accident was an electrical disturbance originating from an experiment package using a commercial-off-the-shelf (COTS) component that had not been properly qualified for the X-15 environment. . .” and that there is “. . . no conclusive evidence to support the hypothesis that SD [spatial disorientation] was a causal factor. On the contrary, the evidence suggests that poor design of the pilot-aircraft interface and ineffective operational procedures prevented the pilot and ground control from recognizing and isolating the numerous failures before the aircraft’s departure from controlled flight was inevitable.”

A Comprehensive Analysis of the X-15 Flight 3-65 Accident, NASA/TM—2014-218538 (Corrected Copy)

Crushed forward fuseleage of X-15 56-6672. (NASA)
Crushed forward fuselage of North American Aviation X-15A-3 56-6672. (NASA)

Michael James Adams was born at Sacramento, California, 5 May 1930. He was the first of two sons of Michael Louis Adams, a telephone company technician, and Georgia E. Domingos Adams.

Michael Adams throws a javelin at Sacramento J.C. (1949 Pioneer)

After high school, Mike Adams attended Sacramento Junior College, graduating in 1949. He was an outfielder for the college baseball team, and threw the javelin in track & field.

Adams enlisted in the United States Air Force in 1950. He completed basic training at Lackland Air Force Base, San Antonio, Texas. In  October 1951, he was selected as an aviation cadet and sent to Spence Air Force Base, near Moultrie, Georgia, for primary flight training. Cadet Adams completed flight training at Webb Air Force Base, Big Spring, Texas. He graduated 25 October 1952. Adams was one of two distinguished graduates in his class and received a commission as an officer in the regular Air Force.

Second Lieutenant Adams was assigned to advanced flight training at Nellis Air Force Base, where he flew the Lockheed F-80 Shooting Star and North American Aviation F-86 Sabre.

In April 1953, lieutenant Adams joined the 80th Fighter-Bomber Squadron at K-13, Suwon, Republic of Korea. He flew 49 combat missions.

Mr. and Mrs. Michael J. Adams, 15 January 1955. (Freida Adams Collection)

Following the Korean War, Lieutenant Adams was assigned to the 613th Fighter Bomber Squadron, 401st Fighter-Bomber Group, at England Air Force Base, Alexandria, Louisiana. The Squadron initially flew the F-86F Sabre and then transitioned to the Republic F-84F Thunderstreak. Adams deployed to Chaumont Air Base, France, for a six-month temporary assignment.

While stationed at England AFB, Lieutenant Adams met Miss Freida Beard. They were married in a ceremony at the Homewood Baptist Church in Alexandria, 15 January 1955. They would have three children, Michael James, Jr., Brent, and Liese Faye Adams.

Michael J. Adams, 1958

In 1958, Adams graduated from the University of Oklahoma at Norman, with a bachelor’s degree in aeronautical engineering. He was a member of the university’s Institute of Aeronautical Sciences. Adams was next assigned to the Massachusetts Institute of Technology, Cambridge, Massachusetts, where he studied astronautics.

Adams’ next military assignment was as a maintenance officer course instructor at Chanute Air Force Base, Rantoul, Illinois.

In 1962, Captain Adams entered an eight-month training program at the Air Force Test Pilot School, Class 62C, at Edwards Air Force Base in the high desert of southern California. He was awarded the A.B. Honts Trophy as the class’s outstanding graduate.

On 17 June 1963, Captain Adams entered the Aerospace Research Pilots School, which was also at Edwards. This was a seven-month course that taught flying skills in advanced vehicles, with an aim to prepare the graduates for space flight, and to create a pool of qualified military test pilots to be selected as astronauts. The Air Force estimated a need for 20 pilots a year for the upcoming X-20 Dyna-Soar and Manned Orbiting Laboratory (M.O.L.) programs. Adams graduated with the second of the four ARPS classes.

Captain Michael J. Adams with a Lockheed F-104 Starfighter.

Adams then became an operation test pilot, conducting stability and control tests for the Northrop F-5A Freedom Fighter. That was followed by an assignment as a project pilot for the Cornell Aeronautical laboratory.

On 13 November 1963, it was announced that Michael Adams was on of the selectees for the M.O.L. program. As a designated Air Force astronaut, Adams was involved in lunar landing simulations during the development of the Apollo Program lunar lander.

Artists conception of the U.S. Air Force Manned Orbiting Laboratory (M.O.L.)

Major Adams was selected as a pilot of the NASA/Air Force X-15 Hypersonic Research Flight Program. (He was the twelfth and final pilot to be accepted into the project.) He made his first X-15 flight on 6 October 1966. He flew the first X-15, 56-6770. A ruptured fuel tank forced him to make an emergency landing at Cuddeback Dry Lake, one of several pre-selected emergency landing sites, about 40 miles (64 kilometers) northeast of Edwards. The duration of the flight was 8 minutes, 26.4 seconds. The X-15 had only reached an altitude of 75,400 feet (22,982 meters) and Mach 3.00.

A North American Aviation X-15 at Cuddeback Lake after an emergency landing. A Piasceki HH-21C is standing by. (U.S. Air Force)

His second flight took place on 29 November 1966. On this flight, he took the # 3 ship, 56-6672, to 92,100 feet (28,072 meters) and Mach 4.65. The flight lasted 7 minutes, 55.9 seconds.

For his third flight, Mike Adams was back in 56-6670, which had been repaired. He flew to an altitude of 133,100 feet (40,569 meters) and reached Mach 5.59 (3,822 miles per hour/6,151 kilometers per hour). This was Adams fastest flight. He landed at Edwards after 9 minutes, 27.9 seconds.

Flight number four for Adams took place on 28 April 1967. Again he flew the # 1 X-15. On this flight, he reached 167,200 feet (50,963 meters) and Mach 5.44. Elapsed time was 9 minutes, 16.0 seconds.

On 15 June 1967, Adams flew # 1 to 229,300 feet (69,891 meters) and Mach 5.14. Duration 9 minutes, 11.0 seconds.

On 25 August 1967, Adams made his sixth flight, his second in the third X-15, 56-6672. The rocket engine shut down after sixteen seconds and had to be restarted. The maximum altitude was 84,400 feet (25,725 meters) and Mach 4.63. The duration of this flight was 7 minutes. 37.0 seconds.

Mike Adams’ seventh flight in an X-15 took place 15 November 1967. This was the 191st X-15 flight, and the 65th for X-15 56-6672. Tests to be conducted were an ultraviolet study of the rocketplane’s exhaust plume; solar spectrum measurements; micrometeorite collection, and a test of ablative material for the Saturn rocket.

Adams reached 266,000 feet (81,077 meters) and Mach 5.20.

Having met the U.S. Air Force qualification for flight in excess of 50 miles (80.47 kilometers), Michael Adams was posthumously awarded the wings of an astronaut.

Major Michael James Adams, United States Air Force, was buried at Mulhearn Memorial Park, in Monroe, Louisiana.

© 2018, Bryan R. Swopes

Facebooktwitterredditpinterestlinkedinmailby feather

9 November 1962

McKAY, John B. (Jack) with X-15 56-6672, 13 March 19649 November 1962: Flight 74 of the X-15 Program was the Number Two aircraft’s 31st flight. X-15 56-6671 was carried aloft by Balls 8, the Boeing NB-52B Stratofortress, 53-008, for launch over Mud Lake, Nevada. NASA test pilot John Barron (“Jack”) McKay was to take the rocketplane to 125,000 feet at Mach 5.5 to investigate the stability and handling of the X-15 with the lower half of the ventral fin removed, and to investigate aerodynamic boundary layer phenomena.

North American Aviation X-15 56-6671 under the right wing of a B-52 Stratofortress at 45,000 feet. (NASA)
North American Aviation X-15 56-6671 under the right wing of a B-52 Stratofortress at 45,000 feet. (NASA)

The B-52 mothership dropped Jack McKay and the X-15 right on schedule at 10:23:07.0 a.m., local time, from an altitude of 45,000 feet (13,716 meters) and speed of approximately 450 knots (833 kilometers per hour). McKay advanced the throttle to ignite the Reaction Motors XLR99-RM-1 rocket engine. It fired immediately but when McKay advanced the throttle for the full 57,000 pounds of thrust, the engine remained at just 30%.

The X-15 could have flown back to Edwards Air Force Base, about 200 miles (320 kilometers) to the south, but with the engine not responding to the throttle, it was uncertain that it would continue running. The decision was made to make an emergency landing at Mud Lake.

Having reached a peak altitude of 53,950 feet (16,444 meters) and Mach 1.49 (1,109 miles per hour/1,785 kilometers per hour), Jack McKay continued to circle the lake burning off propellants as he lost altitude. The engine was shut down at 70.5 seconds. McKay positioned the aircraft for landing as he continued to dump unused propellant and liquid oxygen, but a considerable amount remained on board.

As he neared touchdown, he tried to lower the flaps but they did not deploy. The X-15 touched down on the dry lake bed at 296 miles per hour (476.4 kilometers per hour), 66 miles per hour (106 kilometers per hour) faster than normal.

Duration of the flight from air launch to touchdown was 6 minutes, 31.1 seconds.

The high speed and extra weight caused the X-15’s rear skids to hit harder than normal. When the nose wheels hit, a rebound effect placed even higher loads on the rear struts. At the same time, with the elevators in an extreme nose-up position, the higher aerodynamic loads pushed the skids deeper into the lake bed. This higher loading caused the left rear strut to collapse. The X-15 rolled to the left and the left elevator dug into the lake bed. This caused the aircraft to start sliding to the left. Jack McKay jettisoned the canopy and as the right wing tip dug into the surface, the X-15 flipped over and came to rest upside down.

A Piasecki H-21 rescue helicopter lands near the overturned X-15 at Mud Lake, 9 November 1961. (NASA)
A Piasecki H-21 rescue helicopter lands near the overturned X-15 at Mud Lake, 9 November 1961. (NASA)
The X-15 rolled over when the left landing skid collapsed because of the high-speed, overweight emergency landing at Mud Lake, Nevada. Jack McKay was trapped in the cockpit and suffered serious spinal injuries. (NASA)
The X-15 rolled over when the left landing skid collapsed because of the high-speed, overweight emergency landing at Mud Lake, Nevada. Jack McKay was trapped in the cockpit and suffered serious spinal injuries. (NASA)
The Number Two X-15, 56-6671, lies upside down and severely damaged at Mud Lake, Nevada, 9 November 1962. (NASA)
The Number Two X-15, 56-6671, lies upside down and severely damaged at Mud Lake, Nevada, 9 November 1962. (NASA)

McKay was seriously injured. He was trapped in the upside down X-15 and was in danger from the vapors of the ammonia propellants and liquid oxygen. An H-21 rescue helicopter hovered overhead to blow the vapor away.

Prior to the flight, an Air Force C-130 had brought a fire engine and crew to standby at Mud Lake, returned to Edwards and picked up a second fire engine and its crew, then remained airborne should an emergency landing be made at another intermediate dry lake.

These propositioned emergency assets were able to rescue McKay and to transport him to the hospital back at Edwards.

McKay eventually recovered sufficiently to return to flight status, but ultimately his injuries forced him to retire.

The Number Two X-15 was severely damaged. It was taken back to North American and was rebuilt into the X-15A-2, intended to reach speeds up to Mach 8. It would be more than a year and a half before it flew again.

North American Aviation X-15A-2 56-6671, after a 19-month repair, redesign and modification program. The fuselage was lengthened, additional propellant and reaction control tanks installed internally, the nose wheel and rear landing skid struts lengthened, and external tanks installed. (NASA)
North American Aviation X-15A-2 56-6671, after a 19-month repair, redesign and modification program. The fuselage was lengthened, additional propellant and reaction control tanks installed internally, the nose wheel and rear landing skid struts lengthened, and external tanks installed. (NASA)

© 2016, Bryan R. Swopes

Facebooktwitterredditpinterestlinkedinmailby feather

8 November 1935

Sir Charles Edward Kingsford Smith, MC, AFC (National Archives of Australia, A1200, L93634)
Sir Charles Edward Kingsford Smith, M.C., A.F.C. (National Archives of Australia, A1200, L93634)

On 8 November 1935: Sir Charles Edward Kingsford Smith, M.C., A.F.C., and co-pilot John Thompson Pethybridge disappeared while flying Lady Southern Cross, a Lockheed Altair 8D Special, across the Andaman Sea from Allahabad, Indian Empire, to Singapore, Straits Settlements, a distance of approximately 1,932 nautical miles (2,224 statute miles, or 3,578 kilometers). The aviators were attempting to break a speed record for flight from England to Australia.

The airplane was sighted over Calcutta, British India, at 9:06 a.m., local time.

The pilot of another airplane, Charles James (“Jimmy”) Melrose, who was also en route to Australia, reported that,

“. . . he saw a ‘plane, which must have been Kingsford Smith’s, pass about 200 feet above him at 3 o’clock this morning, when he was over the Bay of Bengal, about 150 miles from land. . . Mr. Melrose said that when he passed over him in the Bay of Bengal Kingsford Smith’s speed was double his own, which was 110 miles an hour. It gave him an uncanny feeling over the desolate ocean to see the spurts of flame coming from the twin exhausts of the Lady Southern Cross. . . Kingsford Smith’s altitude was between 8000 and 9000 feet.”

The Sydney Morning Herald, No. 30,531, Saturday, 9 November 1935, Page 19, Columns 7 and 8

On 1 May 1937, about eighteen months after the disappearance, two Burmese fisherman found a landing gear assembly floating in the Andaman Sea near Kokunye Kyun (Aye Island), off the west coast of Burma. Lockheed was able to confirm that it was from Lady Southern Cross. The component is in the collection of the Powerhouse Museum, Sydney, Australia.

Landing gear assembly of Kingsford Smith’s Lady Southern Cross is in the collection of the Powerhouse Museum venue of the Museum of Applies Arts and Sciences. (MAAS Collection 94/64/1)

In 2009, searchers claimed to have located the wreck of the airplane near the island, but this has not been confirmed.

Lockheed 8-D Altair VH-USB, Lady Southern Cross, at Burbank, California, September 1935. (Unattributed)
Lockheed Altair 8D Special VH-USB, Lady Southern Cross, at Burbank, California, September 1935. The Altair is “. . . painted consolidated blue with silver wing and silver striping. . . .” (David Horn Collection No. 9099)

Kingsford Smith was a former Royal Air Force pilot and flight instructor. He had been a barnstormer, airline pilot, and gained world-wide fame for his trans-Pacific flights. From 31 May to 9 June 1928 he and Charles Ulm, Harry Lyon and James Warner had flown Southern Cross, a Fokker F.VIIB/3m, from Oakland, California to Brisbane, with stops at Hawaii and Fiji. In 1934, with Lady Southern Cross, he and Patrick Gordon Taylor flew from Australia to Hawaii and on to Oakland, California, arriving 4 November.

Charles Kingsford Smith’s Lady Southern Cross at Lockheed, Burbank, California. Note the navigator’s sighting lines on the elevators. (Code One Magazine/Lockheed Martin)

After the transpacific flight, Lady Southern Cross spent the next 11 months at Lockheed being repaired and overhauled. Kingsford Smith then flew it across the United States and had it transported to England aboard a ship.

Lady Southern Cross was a Lockheed Altair 8D Special, a single-engine monoplane with the fuselage, wings and tail surfaces built of spruce. The Altair had been modified from a 1930 Lockheed Sirius 8A Special, NR118W, c/n 152, which was an airplane with fixed landing gear. Lockheed designed a new wing which included retractable landing gear, operated by a hand crank from the cockpit. The Sirius and Altair were single-place utility transports. Kingsford Smith’s Altair was further modified with two cockpits in tandem. Lady Southern Cross was painted Consolidated Blue (a dark blue color) with silver accents.

Sir Charles Edward Kingsford Smith, MC, AFC, with the Lady Southern Cross at Croydon, 17 October 1935. The airplane's registration has been changed to G-ADUS.
Air Commodore Sir Charles Edward Kingsford Smith, Kt, MC, AFC, with the Lady Southern Cross at Croydon, 17 October 1935. The airplane’s registration has been changed to G-ADUS. (PHOTOSHOT)

Lady Southern Cross, designated a Lockheed Altair 8D Special, had a length of 27 feet, 10 inches (8.484 meters) with a wingspan of 42 feet, 9¼ inches (13.037 meters) and height of 9 feet, 3 inches (2.819 meters). The modified airplane had an empty weight of 3,675 pounds (1,667 kilograms) and a maximum gross weight of 6,700 pounds (3,039 kilograms).

The airplane’s standard Pratt & Whitney Wasp C1 engine was replaced at Kingsford Smith’s request with a more-powerful Pratt & Whitney Wasp SE, serial number 5222. The Wasp SE was an air-cooled, supercharged, 1,343.804-cubic-inch-displacement (22.021 liter) single-row 9-cylinder radial engine with a compression ratio of 6:1. It was rated at 500 horsepower at 2,200 r.p.m., at an altitude of 11,000 feet (3,353 meters). The SE was a direct-drive, right-hand tractor engine which turned a two-bladed Hamilton Standard controllable-pitch metal propeller with a diameter of 9 feet, 0 inches (2.743 meters). The Wasp SE was 3 feet, 6.59 inches (1.082 meters) long, 4 feet, 3.44 inches (1.307 meters) in diameter and weighed 750 pounds (340.2 kilograms).

An Altair 8D  had a cruising speed of 175 miles per hour (282 kilometers per hour) and a maximum speed of 207 miles per hour (333 kilometers per hour) at 7,000 feet (2,134 meters). Contemporary news reports stated that Kingsford Smith had reached speeds of 230 miles per hour (370 kilometers per hour) while testing VH-USB.

Sir Charles Edward Kingsford Smith, MC, AFC, At Lympne Airport, Kent, England, 6 November 1935. This may be the last photograph ever taken of "Smithy". (International News Photos)
Air Commodore Sir Charles Edward Kingsford Smith, Kt, MC, AFC, at Lympne Airport, Kent, England, 6 November 1935. This may be the last photograph ever taken of “Smithy.” (International News Photos)

© 2017, Bryan R. Swopes

Facebooktwitterredditpinterestlinkedinmailby feather

5 November 1959

The Number 2 X-15, 56-6671, broke in half when it made an emergency landing while still partially loaded with propellants. (NASA)
The Number 2 X-15, 56-6671, broke in half when it made an emergency landing while still partially loaded with propellants. (NASA)

5 November 1959: During his fourth X-15 flight—the third in the Number Two ship, 56-6671—North American Aviation chief test pilot Albert Scott Crossfield made an emergency landing at Rosamond Dry Lake after one of the two Reaction Motors XLR11-RM-13 rocket engines exploded, causing an engine compartment fire.

The X-15 had been launched by the Boeing NB-52A Stratofortress, 52-003, at 0.82 Mach and approximately 45,000 feet (13,716 meters) over Bouquet Canyon Reservoir, about 35 miles (56 kilometers) southwest of Edwards Air Force Base. Scott Crossfield ignited both XLR11 rocket engines and began to accelerate and climb, but one of four combustion chambers of the lower engine exploded almost immediately. He shut both engines down after 11.7 seconds. Crossfield kept the rocketplane in a level attitude for the 114 seconds it took to jettison the liquid oxygen and water-alcohol propellants to lighten the X-15 for the landing. The tanks could not fully drain and the aircraft remained approximately 1,000 pounds (455 kilograms) overweight.

The X-15 approached the emergency landing site at Rosamond Dry Lake, about ten miles (16 kilometers) southwest of Edwards, while Major Robert M. White, flying a Lockheed F-104 chase plane, called out Crossfield’s distance from the dry lake and his altitude. As he neared the touch down point, Crossfield raised the X-15’s nose to decelerate.

“I lowered the skids and nose wheel, pulled the flaps, and felt for the lake bed.

“The skids dug in gently. The nose wheel slammed down hard and the ship plowed across the desert floor, slowing much faster than usual. Then she came to a complete stop within 1500 feet instead of the usual 5000 feet. Something was wrong; the skids failed, I was sure. . . Quickly I scrambled out of the cockpit. What I saw almost broke my heart. The fuselage had buckled immediately aft of the cockpit, two hundred and thirty inches back from the nose. Her belly had dragged in the sand, causing the abrupt deceleration on the lake. The rocket chambers which had exploded at launch were a shambles.”

Always Another Dawn: The Story of a Rocket Test Pilot, by A. Scott Crossfield and Clay Blair, Jr., The World Publishing Company, Cleveland and New York, 1960, Chapter 41 at Pages 383–384.

The scene at Rosamond Dry Lake after Scott Crossfield's emergency landing after an engine explosion. (NASA)
The scene at Rosamond Dry Lake after Scott Crossfield’s emergency landing following an engine explosion. (NASA)

It was determined that the engine had exploded due to an ignition failure, a relatively simple problem not connected to the design of the X-15. But there remained the question as to why the rocketplane had broken in half. The investigation found that the rapid extension of the nose wheel strut when lowered caused the oil inside the strut to foam and vaporize, providing almost no shock absorption. This was corrected and the check list changed to lower the gear sooner.

The total duration of this flight was 5 minutes, 28.0 seconds. The peak altitude was 45,462 feet (13,857 meters) and the maximum speed was 660 miles per hour (1,062 kilometers per hour).

56-6671 was taken back to the North American Aviation plant for repair. It returned to flight operations three months later.

Test pilot A. Scott Crossfield with the damaged X-15 (UPI/Harry Ransom Center
Test pilot A. Scott Crossfield with the damaged X-15 on Rosamond Dry Lake. (UPI/Harry Ransom Center, University of Texas at Austin)

© 2016, Bryan R. Swopes

Facebooktwitterredditpinterestlinkedinmailby feather

4 November 1941

Lockheed YP-38 Lightning 39-689, manufacturer's serial number 122-2202. (Lockheed)
Lockheed YP-38 Lightning 39-689, manufacturer’s serial number 122-2202. (Lockheed Martin)
Ralph Burwell. Virden (Los Angeles Times)

4 November 1941: Lockheed test pilot Ralph Burwell Virden was conducting high speed dive tests in the first Lockheed YP-38 Lightning, Air Corps serial number 39-689 (Lockheed’s serial number 122-2202).

As the airplane’s speed increased, it approached what is now known as its Critical Mach Number. Air flowing across the wings accelerated to transonic speeds and began to form shock waves. This interrupted lift and caused a portion of the wing to stall. Air no longer flowed smoothly along the airplane and the tail surfaces became ineffective. The YP-38 pitched down into a steeper dive and its speed increased even more.

Designed by famed aeronautical engineer Clarence L. “Kelly” Johnson, the YP-38 had servo tabs on the elevator that were intended to help the pilot maintain or regain control under these conditions. But they increased the elevator’s effectiveness too well.

The Los Angeles Times described the accident:

      Witnesses said the twin-engined, double-fuselaged ship was booming westward at near maximum speed (unofficially reported to be between 400 and 500 miles an hour) when the duralumin tail assembly “simply floated away.”

     A moment afterward the seven-ton craft seemed to put on a burst of speed, the the high whine of its engines rising.

     It then went into a downward glide to about 1500 feet, then into a flat spin, flipped over on its back and shot earthward.

     Several persons said that they thought they had heard an explosion during the dive, but qualified observers doubted it. . .

     . . . Fellow pilots at Lockheed said, “Ralph was the best we had, especially in power dives.”

      Robert E. Gross, president of Lockheed, said, “Ralph Virden was a great pilot but an even greater man. If anyone ever had national defense at heart it was he, who every day was carrying the science of aviation into new and higher fields.”

     Various witnesses said the ill-fated ship’s tail assembly could be followed easily as its bright surfaces glinted in the sun during its drop to earth. It landed several blocks from the scene of the crash.

     Mrs. Jack Davenport of 1334 Elm Ave., left her ironing board when she heard the unfamiliar roar of the plunging plane’s engines.

     “I ran out and saw it passing over us, very low. It disappeared among the trees and then zoomed back into sight just before crashing in the next block,” she said. “It looked just like a toy airplane. I knew the pilot didn’t have a chance, as the ship was too low and going too fast.”

Los Angeles Times, Vol. LX, Wednesday, 5 November 1941, Page 1, Column 6, and Page 2, Column 5.

The YP-38 crashed into the kitchen of Jack Jensen’s home at 1147 Elm Street, Glendale, California. Fire erupted. Ralph Virden was killed. The airplane’s tail section was located several blocks away.

Another view of Lockheed YP-38 Lightning 39-689. It's factory serial number, "2202," is stenciled on the nose. (Lockheed Martin)
Another photograph of Lockheed YP-38 Lightning 39-689. The factory serial number, “2202,” is stenciled on the nose. (Lockheed Martin)

39-689 was the first of thirteen YP-38 service test aircraft that had been ordered by the U.S. Army Air Corps shortly after the XP-38 prototype, 37-457, had crashed on a transcontinental speed record attempt, 11 February 1939. 39-689 made its first flight 16 September 1940 with test pilot Marshall Headle at the controls. With hundreds of production P-38s being built, Lockheed continued to use the YP-38 for testing.

Newspaper phototograph of the wreckage of Lockheed YP-38 Lightning 39-689 at 1147 Elm Street, Glendale, California. (Los Angeles Times)
Newspaper photograph of the wreckage of Lockheed YP-38 Lightning 39-689 at 1147 Elm Street, Glendale, California. (Los Angeles Times)

The YP-38s were service test prototypes of a single-place, twin engine long range fighter with a unique configuration. There was not a fuselage in the normal sense. The cockpit, nose landing gear, and armament were contained in a central nacelle mounted to the wing. Two engines and their turbochargers, cooling systems and main landing gear were in two parallel booms. The booms end with vertical fins and rudders, with the horizontal stabilizer and elevator between them. The P-38 was 37 feet, 9–15/16 inches (11.530 meters) long, with a wingspan of 52 feet, 0 inches (15.850 meters) and height of 12 feet, 10 inches (3.952 meters).

The P-38’s wings had a total area of 327.50 square feet (30.43 square meters). Their angle of incidence was 2° and there was 5° 40′ dihedral. The leading edges were swept aft 5° 10′.

The YP-38 had an empty weight 11,171 pounds (5,067 kilograms). The gross weight was 13,500 pounds (6,123 kilograms) and the maximum takeoff weight 14,348 pounds (6,508 kilograms).

The YP-38 was powered by two counter-rotating, liquid-cooled, turbosupercharged 1,710.597-cubic-inch displacement (28.032 liter) Allison V-1710-27 right-hand tractor and V-1710-29 left-hand tractor, single overhead cam (SOHC) 60° V-12 engines (Allison Engineering Co. Models F2R and F2L) with a Normal Power rating of 1,000 horsepower at 2,600 r.p.m., and 1,150 horsepower at 3,000 r.p.m. for takeoff. They drove three-bladed Curtiss Electric constant-speed propellers with a diameter of 11 feet, 6 inches (3.505 meters) through a 2.00:1 gear reduction. In a change from the XP-38, the propellers rotated outboard at the top of their arc. The V-1710-27/-29 engines were 7 feet, 1-5/8 inches (2.175 meters) long, 2 feet, 5-9/32 inches (0.744 meters) wide and 3 feet, 0-17/32 inches (0.928 meters) high. The V-1710-27/-29 weighed 1,305 pounds (592 kilograms)

The YP-38 had a maximum speed of 405 miles per hour (651.8 kilometers per hour) at 10,000 feet (3,048 meters) and it could climb  from the surface to 20,000 feet (6,096 meters) in six minutes. Normal range 650 miles (1,046 kilometers).

Lockheed built one XP-38, thirteen YP-38s, and more than 10,000 production fighter and reconnaissance airplanes. At the end of World War II, orders for nearly 2,000 more P-38 Lightnings were cancelled.

Lockheed YP-38 39-692 in flight.(Hans Groenhoff Photographic Collection, Smithsonian Institution National Air and Space Museum NASM-HGC-967)

Ralph Burwell Virden was born 11 June 1898, at Audobon Township, Illinois. He was the second child of Hiram R. Virden, a farmer, and Nancy Carrie Ivy Virden.

Virden attended Bradley Polytechnic Institute at Peoria, Illinois. At the age of 17, 15 October 1918, Ralph Virden enlisted in the U.S. Army. With the end of World War I less than one month later, he was quickly discharged, 7 December 1918.

In 1919, Ralph Virden married Miss Florence I. McCullers. They would have two children, Kathryn and Ralph, Jr. Kathryn died in 1930 at the age of ten years.

Ralph Burwell Virden with a Boeing Model 40 mail plane, circa late 1920s. As a U.S. Air Mail pilot, Virden is armed with a .45-caliber Colt M1911 semi-automatic pistol. (San Diego Air and Space Museum Archives)
Boeing Airplane Company President Clairmont L. Egvtedt and United Air Lines Captain Ralph B. Virden examine a scale model of the Boeing 247D airliner. (Boeing)

During the mid-1920s, Virden flew as a contract mail pilot. He held Airline Transport Pilot Certificate No. 628, and was employed by Gilmore Aviation and Pacific Air Transport. For thirteen years, Virden was a pilot for United Air Lines. He joined Lockheed Aircraft Company as a test pilot in 1939. He had flown more than 15,000 hours.

Virden lived at 4511 Ben Ave., North Hollywood, California, with his  family. Ralph, Jr., now 19 years of age, was also employed at Lockheed. (Following his father’s death, the younger Virden enlisted in the United States Navy.)

After the accident, Lockheed, the Air Corps and the National Advisory Committee on Aeronautics (NACA) undertook an extensive test program of the P-38.

The Lockheed YP-38 Lightning, 39-690, was sent to the NACA Research Center at Langley Field, Virginia. This photograph is dated 4 February 1942. (NASA)
The second Lockheed YP-38 Lightning, 39-690, was sent to the NACA Langley Research Center at Langley Field, Virginia. This photograph is dated 4 February 1942. (NASA)
Lockheed YP-38 39-690 in the NACA Full Scale Tunnel, December 1944. (NASA)
Lockheed YP-38 39-690 in the NACA Full Scale Tunnel, December 1944. (NASA)
Lockheed YP-38 Lightning 39-690, serial number 122-2203. (NASA)
Lockheed YP-38 Lightning 39-690, serial number 122-2203. (NASA)
Lockheed YP-38 #2 in the NACA full-scale wind tunnel at Langley, Virginia. (NASA)
Lockheed YP-38 Lightning, 39-690 (122-2203), in the NACA Langley Research Center’s full-scale wind tunnel at Langley Field, Virginia, December 1944. (NASA)
Lockheed YP-38 Lightning 39-690. (NASA)
Lockheed YP-38 Lightning 39-690. (NASA)
Lockheed YP-38 Lightning 39-690. (NASA)
Lockheed YP-38 Lightning 39-690. (NASA)
Lockheed YP-38 Lightning 39-690. (NASA)
Lockheed YP-38 Lightning 39-690. (NASA)
Lockheed YP-38 Lightning 39-690, 122-2203. (NASA)
Lockheed YP-38 Lightning 39-690, 122-2203. (NASA)

© 2018, Bryan R. Swopes

Facebooktwitterredditpinterestlinkedinmailby feather