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41-511: The D558 program was conceived as a joint NACA/U.S. Navy research program for transonic and supersonic flight . As originally envisioned, there would be three phases to the D558 program: a jet-powered airplane, a mixed rocket/jet-powered configuration, and a design and mockup of a combat aircraft. A contract for design and construction of six D558-1 aircraft for the first phase was issued on 22 June 1945. The original plan had been for six aircraft with

82-461: A German mathematician and engineer at Braunschweig , discovered Tricomi's work in the process of applying the hodograph method to transonic flow near the end of World War II. He focused on the nonlinear thin-airfoil compressible flow equations, the same as what Tricomi derived, though his goal of using these equations to solve flow over an airfoil presented unique challenges. Guderley and Hideo Yoshihara, along with some input from Busemann, later used

123-474: A far distance they are invariably supersonic. Supernovae explosions are accompanied by supersonic flows and shock waves. Bow shocks formed in solar winds are a direct result of transonic winds from a star. It had been long thought that a bow shock was present around the heliosphere of our solar system, but this was found not to be the case according to IBEX data published in 2012. Carolinas Aviation Museum The Sullenberger Aviation Museum , formerly

164-453: A fatal plane accident. He lost control of the plane when a shock wave caused by supersonic airflow developed over the wing, causing it to stall. Virden flew well below the speed of sound at Mach 0.675, which brought forth the idea of different airflows forming around the plane. In the 40s, Kelly Johnson became one of the first engineers to investigate the effect of compressibility on aircraft. However, contemporary wind tunnels did not have

205-711: A few minutes after takeoff forced a ditching in the Hudson River . The ditching and subsequent rescue operations were accomplished without loss of life. The aircraft, an A320-214, was eventually recovered from the river. In January 2011, the Carolinas Aviation Museum acquired the entire airframe from the insurance company, AIG, who donated the aircraft to the museum. The airframe was transported by road from its storage location at J Supor & Son Trucking & Rigging Co. Inc. in Kearny , New Jersey to

246-485: A flow speed close to or at Mach 1 does not allow the streamtubes (3D flow paths) to contract enough around the object to minimize the disturbance, and thus the disturbance propagates. Aerodynamicists struggled during the earlier studies of transonic flow because the then-current theory implied that these disturbances– and thus drag– approached infinity as local Mach number approached 1, an obviously unrealistic result which could not be remedied using known methods. One of

287-440: A large collection of artifacts and memorabilia from various legacy airlines which merged into the now-defunct US Airways. The museum's special collections and archival material are currently in storage and inaccessible for research. The collection includes artifacts from: On January 15, 2009, US Airways Flight 1549 took off from New York's LaGuardia Airport for a flight to Charlotte , North Carolina, when multiple bird strikes

328-464: A mixture of nose and side air inlets and varying wing airfoil sections. That plan was quickly reduced to three aircraft of a single configuration with a nose inlet. Plans for the second phase with mixed rocket/jet propulsion were also dropped. Instead, a new aircraft, the D558-2 , was designed with mixed rocket and jet propulsion for supersonic flight. Construction of the first 558-1 began in 1946 and

369-515: A new facility at the Charlotte-Douglas International Airport at 4672 First Flight Drive. The new facility has enabled the majority of the aircraft to be inside a climate-controlled facility, as well as allowing for new displays. In October 2012, the museum became a Smithsonian affiliate . In July 2019, the museum closed to the public and all aircraft were moved into temporary storage in preparation for

410-510: A rapid increase in drag from about Mach 0.8, and it is the fuel costs of the drag that typically limits the airspeed. Attempts to reduce wave drag can be seen on all high-speed aircraft. Most notable is the use of swept wings , but another common form is a wasp-waist fuselage as a side effect of the Whitcomb area rule . Transonic speeds can also occur at the tips of rotor blades of helicopters and aircraft. This puts severe, unequal stresses on

451-499: A singular solution of Tricomi's equations to analytically solve the behavior of transonic flow over a double wedge airfoil , the first to do so with only the assumptions of thin-airfoil theory. Although successful, Guderley's work was still focused on the theoretical, and only resulted in a single solution for a double wedge airfoil at Mach 1. Walter Vincenti , an American engineer at Ames Laboratory , aimed to supplement Guderley's Mach 1 work with numerical solutions that would cover

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492-583: A total of 78 research flights with the NACA before being retired on June 10, 1953. The third Skystreak is on display at Carolinas Aviation Museum located at the Charlotte-Douglas International Airport (CLT) in Charlotte, North Carolina . The Skystreak reached Mach 0.99 in level flight, but only flew supersonic in a dive. In the public mind, much of the research performed by the D-558-1 Skystreaks

533-521: Is Mach 1 and the Prandtl–Glauert singularity . In astrophysics, wherever there is evidence of shocks (standing, propagating or oscillating), the flow close by must be transonic, as only supersonic flows form shocks. All black hole accretions are transonic. Many such flows also have shocks very close to the black holes. The outflows or jets from young stellar objects or disks around black holes can also be transonic since they start subsonically and at

574-466: Is air flowing around an object at a speed that generates regions of both subsonic and supersonic airflow around that object. The exact range of speeds depends on the object's critical Mach number , but transonic flow is seen at flight speeds close to the speed of sound (343 m/s at sea level), typically between Mach 0.8 and 1.2. The issue of transonic speed (or transonic region) first appeared during World War II. Pilots found as they approached

615-419: Is that disturbances within the flow are relatively small, which allows mathematicians and engineers to linearize the compressible flow equations into a relatively easily solvable set of differential equations for either wholly subsonic or supersonic flows. This assumption is fundamentally untrue for transonic flows because the disturbance caused by an object is much larger than in subsonic or supersonic flows;

656-606: The Carolinas Aviation Museum , is an aviation museum on the grounds of Charlotte Douglas International Airport in Charlotte, North Carolina . It is one of a few aviation museums located at an airport which serves as a major hub (Charlotte is the No. 2 hub for American Airlines ). Its centerpiece attraction is the Airbus A320 used on US Airways Flight 1549 . In 1992, Floyd and Lois Peithman Wilson founded

697-574: The Navy and Douglas the second D-558-1 aircraft was delivered to the NACA in November 1947. The D-558-1 #2 underwent extensive instrumentation by the NACA Muroc instrumentation section. The number 2 Skystreak made a total of 19 flights with the NACA before it crashed on takeoff due to compressor disintegration on May 3, 1948, killing NACA pilot Howard C. Lilly . The third D-558-I, BuNo 37972 , aircraft

738-409: The best wingtip shape for sonic speeds. After World War II , major changes in aircraft design were seen to improve transonic flight. The main way to stabilize an aircraft was to reduce the speed of the airflow around the wings by changing the chord of the plane wings, and one solution to prevent transonic waves was swept wings. Since the airflow would hit the wings at an angle, this would decrease

779-637: The birds and tugboat. In addition to the airframe, Captain Sullenberger and First Officer Skiles contributed their uniforms to the museum's 1549 exhibit. The aircraft arrived in June 2011, and reassembly of the main components took about one year. The engines arrived in May 2012 and were planned to be reassembled in time for the fourth anniversary of the landing in the Hudson, on January 15, 2013. The museum opened

820-494: The capability to create wind speeds close to Mach 1 to test the effects of transonic speeds. Not long after, the term "transonic" was defined to mean "across the speed of sound" and was invented by NACA director Hugh Dryden and Theodore von Kármán of the California Institute of Technology. Initially, NACA designed "dive flaps" to help stabilize the plane when reaching transonic flight. This small flap on

861-706: The first axial-flow turbojets of American origin — and carried 230 US gallons (871 L) of jet fuel (kerosene). All the Skystreaks were initially painted scarlet, which led to the nickname crimson test tube. NACA later had the color of the Skystreaks changed to white to improve optical tracking and photography. The first of three D-558-1 Skystreaks, BuNo 37970 , made its maiden flight on 14 April 1947, at Muroc Army Air Field (later named Edwards AFB ). Less than 4 months later, on August 20, this aircraft with Commander Turner Caldwell , USN, reached 640.744 mph (1,031.178 km/h; 556.791 kn) flying D-558-1 #1. This

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902-562: The first methods used to circumvent the nonlinearity of transonic flow models was the hodograph transformation. This concept was originally explored in 1923 by an Italian mathematician named Francesco Tricomi , who used the transformation to simplify the compressible flow equations and prove that they were solvable. The hodograph transformation itself was also explored by both Ludwig Prandtl and O.G. Tietjen's textbooks in 1929 and by Adolf Busemann in 1937, though neither applied this method specifically to transonic flow. Gottfried Guderley,

943-569: The museum announced a US$ 1 million gift from Red Ventures CEO Ric Elias, who survived the flight, and a US$ 500,000 gift from Lonely Planet . The museum broke ground on its new facility in September 2022. In October 2023, as part of the rebuilding process, the museum announced a new logo. In advance of the official opening, which took place on June 1, 2024, a ribbon cutting was held on May 29, 2024, with Sullenberger himself attending. The museum's collections include: The museum holds

984-424: The museum at Charlotte Douglas International Airport in Charlotte . The transportation took 7 days, between June 4 and 10, 2011, and covered 788 miles (1,268 km) through New Jersey, Delaware, Maryland, West Virginia, Virginia, and North Carolina. Because the fuselage was transported in one piece, as it was when it was recovered from the river, the truck was 190 feet (58 m) long. Virtually everything except

1025-603: The museum no longer operates flying aircraft, it has on occasion hosted historic aircraft for fly-ins, since it is located on Charlotte-Douglas International Airport property. Those aircraft include the B-17 , B-24 , B-29 , and Berlin Airlift C-54 . Until April 2010, the museum was located in the airport's original 1932 hangar, built by the Works Progress Administration . The museum moved into

1066-677: The museum, which has a collection of over 50 static aircraft and many smaller historic items related to aviation in North Carolina and South Carolina . Most of the collection consists of Cold War military aircraft, including several historic jet aircraft from the 1950s and 1960s. Many of the aircraft came over from the now-closed Florence Air & Missile Museum , formerly in Florence, South Carolina. A significant number of aircraft have also come from Marine Corps Air Station Cherry Point and Marine Corps Air Station New River . Although

1107-415: The new facility. The museum developed plans for a new location with a planned re-opening in 2024. In June 2021, the museum announced plans to reopen with a new main gallery and welcome center adjacent to the original 1932 hangar. On January 14, 2022, the museum announced that it would be renamed for Chesley B. "Sully" Sullenberger . The museum was to house a permanent Miracle on the Hudson exhibit. Also,

1148-598: The passengers' personal belongings are still in the airplane. The landing gear pins, fire axe, and the manuals were still in the cockpit, and the Coke cans were still in the beverage carts. The airframe has been reassembled and was on display from 2011 to 2019 in the same configuration as it was when it was pulled out of the Hudson River in January 2009. The airframe is being preserved as opposed to restored with dents from

1189-412: The range of transonic speeds between Mach 1 and wholly supersonic flow. Vincenti and his assistants drew upon the work of Howard Emmons as well as Tricomi's original equations to complete a set of four numerical solutions for the drag over a double wedge airfoil in transonic flow above Mach 1. The gap between subsonic and Mach 1 flow was later covered by both Julian Cole and Leon Trilling , completing

1230-406: The rotor blade and may lead to accidents if it occurs. It is one of the limiting factors of the size of rotors and the forward speeds of helicopters (as this speed is added to the forward-sweeping [leading] side of the rotor, possibly causing localized transonics). Issues with aircraft flight relating to speed first appeared during the supersonic era in 1941. Ralph Virden, a test pilot, crashed in

1271-483: The sound barrier the airflow caused aircraft to become unsteady. Experts found that shock waves can cause large-scale separation downstream, increasing drag, adding asymmetry and unsteadiness to the flow around the vehicle. Research has been done into weakening shock waves in transonic flight through the use of anti-shock bodies and supercritical airfoils . Most modern jet powered aircraft are engineered to operate at transonic air speeds. Transonic airspeeds see

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1312-401: The tail of the aircraft will reach supersonic flight while the nose of the aircraft is still in subsonic flight. A bubble of supersonic expansion fans terminating by a wake shockwave surround the tail. As the aircraft continues to accelerate, the supersonic expansion fans will intensify and the wake shockwave will grow in size until infinity is reached, at which point the bow shockwave forms. This

1353-437: The transonic behavior of the airfoil by the early 1950s. At transonic speeds supersonic expansion fans form intense low-pressure, low-temperature areas at various points around an aircraft. If the temperature drops below the dew point a visible cloud will form. These clouds remain with the aircraft as it travels. It is not necessary for the aircraft as a whole to reach supersonic speeds for these clouds to form. Typically,

1394-419: The underside of the plane slowed the plane to prevent shock waves, but this design only delayed finding a solution to aircraft flying at supersonic speed. Newer wind tunnels were designed, so researchers could test newer wing designs without risking test pilots' lives. The slotted-wall transonic tunnel was designed by NASA and allowed researchers to test wings and different airfoils in transonic airflow to find

1435-478: The wing thickness and chord ratio. Airfoils wing shapes were designed flatter at the top to prevent shock waves and reduce the distance of airflow over the wing. Later on, Richard Whitcomb designed the first supercritical airfoil using similar principles. Prior to the advent of powerful computers, even the simplest forms of the compressible flow equations were difficult to solve due to their nonlinearity . A common assumption used to circumvent this nonlinearity

1476-743: Was broken by then-Lieutenant Colonel Marion Carl , USMC, going 10 mph (16 km/h; 8.7 kn) faster in D-558-1 #2, BuNo 37971 . This aircraft was delivered to the NACA Muroc Flight Test Unit in April 1949 after 101 flights had been completed by the Navy, Air Force, and Douglas. This aircraft was never flown by the NACA. The D-558-1 #1 is located at the National Naval Aviation Museum at Naval Air Station Pensacola , Florida . Following 27 flights by

1517-431: Was completed in January 1947. The fuselage used lightweight, high strength HK31 magnesium alloy extensively, while the wings were fabricated from more conventional aluminum alloys. The airframe was designed to withstand unusually high loads of up to 18 times gravity due to the uncertainties of transonic flight. The forward fuselage, including the cockpit, could be jettisoned from the aircraft in an emergency. The aircraft

1558-457: Was configured to carry more than 500 pounds (230 kg) of test equipment, including sensors (such as strain gauges and accelerometers) in 400 locations throughout the aircraft. One wing was pierced by 400 small holes for the pressure measurements required for calculating airloads. The Skystreaks were powered by one Allison J-35-A-11 engine (developed by General Electric as the TG-180) — one of

1599-435: Was delivered to the NACA Muroc Flight Test Unit in 1949 after three Douglas test pilots and Howard Lilly had flown it. The number three aircraft took over the planned flight program of the D-558-1 #2. From the first flight in 1949 through 1953 the third Skystreak was flown in an intensive flight-research program by seven NACA test pilots, with a great deal of useful data collected on high-subsonic handling. The D-558-1 #3 made

1640-769: Was quickly overshadowed by Chuck Yeager and the supersonic Bell X-1 rocket plane. However, the Skystreak performed an important role in aeronautical research by flying for extended periods of time at transonic speeds, which freed the X-1 to fly for limited periods at supersonic speeds. Data from McDonnell Douglas aircraft since 1920 : Volume I, Jane's all the World's Aircraft 1949-50 General characteristics Performance Related development Aircraft of comparable role, configuration, and era Related lists Transonic Transonic (or transsonic ) flow

1681-585: Was recognised as an official world air speed record , as the World War II German Me 163B V18 Komet rocket fighter prototype that was claimed to have reached 1,130 km/h (702 mph; 610 kn) in July 1944 did so in secrecy and not under the strict conditions that regulate official records (presence of FIA officials as observers, timed runs in two directions to cancel out wind speed, etc). The D-558-1 #1 Skystreak's record lasted 5 days, and

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