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Walter C. Williams (1919-199
Unveiling of sign for Walter
D-558-2 pilot entry from P2B
| Title |
D-558-2 pilot entry from P2B-1S mothership |
| Description |
This 28-second video clip shows Scott Crossfield descending from the bomb bay of the P2B-1S into the cockpit of the D-558-2, strapping in, and having the hatch closed by a crewmember. The Douglas D-558-2 Skyrocket airplanes were among the early transonic research airplanes like the X-1, X-4, X-5, and X-92A. Three of these single-seat, swept-wing aircraft flew from 1948 to 1956 in a joint program involving the National Advisory Committee for Aeronautics (NACA), the Navy-Marine Corps, and the Douglas Aircraft Company, Long Beach, California. Flight research was done at the NACA Muroc Flight Test Unit in California, redesignated in 1949 the High-Speed Flight Research Station (HSFRS). The HSFRS is now known as the NASA Dryden Flight Research Center, Edwards, California. The Skyrocket made aviation history when it became the first airplane to fly twice the speed of sound. Douglas Aircraft pilot John F. Martin made the first flight at Muroc Army Airfield (later renamed Edwards Air Force Base) in California on February 4, 1948. The goals of that program were to investigate the characteristics of swept-wing aircraft at transonic and supersonic speeds with particular attention to pitchup (uncommanded rotation of the nose of the airplane upwards) -- a problem prevalent in high-speed service aircraft of that era, particularly at low speeds during takeoff and landing and in tight turns. The three aircraft gathered a great deal of data about pitchup and the coupling of lateral (yaw) and longitudinal (pitch) motions, wing and tail loads, lift, drag, and buffeting characteristics of swept-wing aircraft at transonic and supersonic speeds, and the effects of the rocket exhaust plume on lateral dynamic stability throughout the speed range. (Plume effects were a new experience for aircraft.) The number three aircraft also gathered information about the effects of external stores (bomb shapes, drop tanks) upon the aircraft behavior in the transonic region (roughly 0.7 to 1.3 times the speed of sound). In correlation with data from other early transonic research aircraft such as the XF-92A, this information contributed to solutions to the pitchup problem in swept-wing aircraft. The Navy contracted with Douglas Aircraft Company to design the airplane, and in the course of the design process, the D-558 came to be divided into two separate phases. Phase one was a straight-wing turbojet aircraft and phase two consisted of a swept-wing design with turbojet and rocket propulsion. At the NACA suggestion, which was based on the research of Robert Jones at Langley and some captured German documents, Douglas Aircraft and the Navy had agreed to the swept-wing design and to provide sufficient power to propel the swept-wing airplane past Mach 1. They also agreed to add rocket propulsion. Then, to fit both a turbojet and rocket engine in the phase two aircraft a new fuselage was required. Like the D-558-1, the Skyrocket featured a horizontal stabilizer high on the vertical tail to, at transonic speeds. While fences significantly aided recovery from pitchup conditions, leading edge chord extensions did not, disproving wind-tunnel tests to the contrary. Slats (long, narrow auxiliary airfoils) in the fully open position eliminated pitchup except in the speed range around Mach 0.8 to 0.85. In June 1954, Crossfield began an investigation of the effects of external stores (bomb shapes and fuel tanks) upon the Skyrocket transonic behavior. McKay and Stanley Butchart completed the NACA investigation of this issue, with McKay flying the final mission on August 28, 1956. Besides setting several records, the Skyrocket pilots had gathered important data and understanding about what would and would not work to provide stable, controlled flight of a swept-wing aircraft in the transonic and supersonic flight regimes. The data they gathered also helped to enable a better correlation of wind-tunnel test results with actual flight values, enhancing the abilities of designers to produce more capable aircraft for the armed services, especially those with swept wings. Moreover, data on such matters as stability and control from this and other early research airplanes aided in the design of the century series of fighter airplanes, all of which featured the movable horizontal stabilizers first employed on the X-1 and D-558 series., avoid the wake from the wing. As with the X-1 and the D-558-1, the Skyrocket also featured, at NACA suggestion, a horizontal stabilizer that was thinner than the wing and movable in flight so as to avoid simultaneous shock wave effects for the wing and horizontal tail and to provide pitch (noseup or nosedown) control when shock waves made the elevators ineffective. While Douglas Aircraft was constructing the D-558-2 airplanes, the NACA continued to furnish the contractor data it needed on aircraft performance based on tests in Langley Research Center wind tunnels and with rocket-propelled models from the Wallops Island Pilotless Aircraft Research Station, Wallops Island, Virginia. The three airplanes flew a total of 313 times -- 123 by the number one aircraft (Bureau No. 37973 -- NACA 143), 103 by the second Skyrocket (Bureau No. 37974 -- NACA 144), and 87 by airplane number three (Bureau No. 37975 -- NACA 145). Skyrocket 143 flew all but one of its missions as part of the Douglas Aircraft contractor program to test the airplane's performance. NACA aircraft 143 was initially powered by a Westinghouse J-34-40 turbojet engine configured only for ground takeoffs, but in 1954-55 the contractor modified it to an all-rocket air-launch capability featuring an LR8-RM-6, 4-chamber Reaction Motors engine rated at 6,000 pounds of thrust at sea level (the Navy designation for the Air Force LR-11 used in the X-1). In this configuration, NACA research pilot John McKay flew the airplane only once for familiarization on September 17, 1956. The 123 flights of NACA 143 served to validate wind-tunnel predictions of Skyrocket performance, except for the fact that the airplane experienced less drag above Mach 0.85 than the wind tunnels had indicated. NACA 144 also began its flight program with a turbojet powerplant. NACA pilots Robert A. Champine and John H. Griffith flew 21 times in this configuration to test airspeed calibrations and to research longitudinal and lateral stability and control. In the process, during August of 1949 they encountered pitchup problems, which NACA engineers recognized as serious because pitchup could produce a limiting and dangerous restriction on flight performance. Hence, they determined to make a complete investigation of the problem. In 1950, Douglas Aircraft Company replaced the turbojet with an LR-8 rocket engine, and its pilot, William B. Bridgeman, flew the aircraft seven times -- up to a speed of Mach 1.88 (1.88 times the speed of sound) and an altitude of 79,494 feet (the latter an unofficial world altitude record at the time, achieved on August 15, 1951). In the rocket configuration, a Navy P2B (Navy version of the B-29) launched the airplane at an altitude of approximately 30,000 feet after taking off from the ground with the Skyrocket attached beneath its bomb bay. During Bridgeman's supersonic flights, he encountered a violent rolling motion known as lateral instability. This phenomenon was less pronounced on the Mach 1.88, flight on August 7, 1951, than on a Mach 1.85 flight in June when he pushed over to a low angle of attack (angle of the fuselage or wing to the prevailing wind direction). The NACA engineers studied the behavior of this aircraft before beginning their own flight research in the airplane in September 1951. Over the next couple of years, NACA pilot A. Scott Crossfield flew the airplane 20 times to gather data on longitudinal and lateral stability and control, wing and tail loads, and lift, drag, and buffeting characteristics at speeds up to Mach 1.878. At that point, Marine Lt. Col. Marion Carl flew the airplane to a new (unofficial) altitude record of 83,235 feet on August 21, 1953, and to a maximum speed of Mach 1.728. Following Carl's completion of these flights for the Navy, NACA technicians at the High-Speed Flight Research Station (HSFRS) near Mojave, California, outfitted the LR-8 engine cylinders with nozzle extensions to prevent the exhaust gas from affecting the rudders at supersonic speeds. This addition also increased the engine thrust by 6.5 percent at Mach 1.7 and an altitude of 70,000 feet. Even before Marion Carl had flown the Skyrocket, HSFRS Chief Walter C. Williams had unsuccessfully petitioned NACA headquarters to fly the aircraft to Mach 2 to garner the research data at that speed. Finally, after Crossfield had secured the agreement of the Navy Bureau of Aeronautics, NACA director Hugh L. Dryden relaxed the organization's usual practice of leaving record setting to others and consented to attempting a flight to Mach 2. In addition to adding the nozzle extensions, the NACA flight team at the HSFRS chilled the fuel (alcohol) so more could be poured into the tank and waxed the fuselage to reduce drag. With these preparations and employing a flight plan devised by project engineer Herman O. Ankenbruck to fly to an altitude of approximately 72,000 feet and push over into a slight dive, Crossfield made aviation history on November 20, 1953, when he flew to Mach 2.005 (1,291 miles per hour). He became the first pilot to reach Mach 2 in this, the only flight in which the Skyrocket flew that fast. Following this flight, Crossfield and NACA pilots Joseph A. Walker and John B. McKay flew the airplane for such purposes as to gather data on pressure distribution, structural loads, and structural heating. The last flight in the program occurred on December 20, 1956, when McKay obtained dynamic stability data and sound-pressure levels at transonic speeds and above. Meanwhile, NACA 145 had completed 21 contractor flights by Douglas Aircraft pilots Eugene F. May and Bill Bridgeman in November 1950. In this jet-and-rocket-propelled craft, Scott Crossfield and Walter Jones began the NACA investigation of pitchup lasting from September 1951 well into the summer of 1953. They flew the Skyrocket with a variety of wing-fence, wing-slat, and leading-edge chord extension configurations, performing various maneuvers as well as straight-and-level flying |
| Date |
01.01.1954 |
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Unveiling of sign for Walter
| Title |
Unveiling of sign for Walter C. Williams Research Aircraft Integration Facility |
| Description |
In a brief ceremony following a memorial service for the late Walter C. Williams on November 17, 1995, the Integrated Test Facility (ITF) at the NASA Dryden Flight Research Center at Edwards, California, was formally renamed the Walter C. Williams Research Aircraft Integration Facility. Shown is the family of Walt Williams: Helen, his widow, sons Charles and Howard, daughter Elizabeth Williams Powell, their spouses and children unveiling the new sign redesignating the Facility. The test facility provides state-of-the-art capabilities for thorough ground testing of advanced research aircraft. It allows researchers and technicians to integrate and test aircraft systems before each research flight, which greatly enhances the safety of each mission. In September 1946 Williams became engineer-in-charge of a team of five engineers who arrived at Muroc Army Air Base (now Edwards AFB) from the National Advisory Committee for Aeronautics's Langley Memorial Aeronautical Laboratory, Hampton, Virginia (now NASA's Langley Research Center), to prepare for supersonic research flights in a joint NACA-Army Air Forces program involving the rocket-powered X-1. This established the first permanent NACA presence at the Mojave Desert site although initially the five engineers and others who followed them were on temporary assignment. Over time, Walt continued to be in charge during the many name changes for the NACA-NASA organization, with Williams ending his stay as Chief of the NASA Flight Research Center in September 1959 (today NASA's Dryden Flight Research Center). |
| Date |
01.01.1995 |
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Walter C. Williams
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Walter C. Williams |
| Description |
Walter C. Williams arrived from the National Advisory Committee for Aeronautics, Langley Memorial Aeronautical Laboratory, Hampton, Virginia, on September 30, 1946, at the Muroc Army Air Field. He had been named the engineer-in-charge of the small group of five that came with him to the Rogers Dry Lakebed to take part in research flights of a joint NACA-Army Air Forces program involving the rocket-powered Bell XS-1. This established the first permanent National Advisory Committee for Aeronautics presence at the Mojave Desert site in California. This small group grew in numbers to 27 and received permanent status as the NACA Muroc Flight Test Unit from Hugh L. Dryden, NACA's Director of Research, on September 27, 1947. Walt was named Head of the Unit. On November 14, 1949, the Unit along with the 100 employees became the NACA High-Speed Flight Research Station with Walt Williams as Chief. Next came the move from the South Base site to the new headquarters, Bldg. 4800 on the north-west shore of the Rogers Dry lakebed on the Edwards Air Force Base complex. July 1, 1954 saw another name change to the NACA High-Speed Flight Station with Walt remaining the Chief to a complement of about 225 employees. Williams had received a Bachelor of Science Degree in aeronautical engineering from Louisiana State University, Baton Rouge, Louisiana, in 1939. After graduation, he was employed by the Glenn L. Martin Company of Baltimore, Maryland, and later that same year joined the staff of the NACA Langley Memorial Aeronautical Laboratory, where he worked as an engineer in the Flight Division. During the period from September 1946 to July 1954 Williams supervised the activities of several research projects. These included the first successful rocket-powered flight of the XS-1 made by Bell pilot Chalmers Goodlin on December 9, 1946, the record breaking flight of A.F. Captain Chuck Yeager on October 14, 1947, that exceeded the speed of sound, and the first flight of the jet-powered Douglas D-558-1 Skystreak by NACA pilot Howard C. Lilly on November 25, 1947. On March 10, 1948, Herbert Hoover was the first NACA pilot and the first civilian to fly supersonically (in the XS-1). Then came the testing of the tailless Northrop X-4 aircraft, the first flight of the variably swept wing Bell X-5 made by NACA pilot Joseph A. Walker, the first NACA flight of the Convair XF-92A, a delta wing configuration, on April 9, 1953, followed by the first Mach 2 flight on November 20, 1953, flown by NACA pilot Scott Crossfield in the rocket-powered Douglas D-558-2 Skyrocket. Walt continued to be in charge during the many name changes for the NACA-NASA organization, ending his stay as Chief of the National Aeronautics and Space Administration's Flight Research Center (todays NASA's Dryden Flight Research Center) in September 1959. See DIRECTORS, E-1364 for further information on Walter C. Williams. |
| Date |
01.01.1949 |
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Walter C. Williams with Brig
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Walter C. Williams with Brig. General Albert Boyd |
| Description |
Walter C. Williams, (behind airplane model) Head of the National Advisory Committee for Aeronautics High-Speed Flight Research Station at Edwards Air Force Base in California is examining a Northrop X-4 research airplane with Brig. Gen. Albert Boyd, Commander of Edwards Air Force Base. At Edwards, the Air Force Air Material Command ran a brief program on the X-4 during the summer of 1950 before delivering it to the NACA. Data was collected on these 14 flights, so they were logged as NACA test flights. General Boyd made flight number 13. Air Force and NACA pilots completed a total of 82 flights on X-4 #2 (46-677) between August 1950 and September 1953. There are three things that made the Mojave Desert, where Edwards Air Force Base is located, so well suited for flight research. The first was the area's flying conditions--clear skies with great visibility almost every day of the year. The second was the 44-square-mile Rogers Dry Lake, a natural landing site that General Boyd referred to as "God's gift to the Air Force." The third was the unpopulated area surrounding the lakebed, which led to fewer complaints about aircraft noise (including sonic booms) than would have occurred in more populated areas. There was also less chance of injury to the surrounding population in the event of an aircraft accident. |
| Date |
01.01.1950 |
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