Misplaced Pages

#880119

95-828: Highlights of the museum included a collection of over 40 aircraft including military fighters, bombers, rescue, recon, and cargo aircraft. Many of these were used for training purposes at Chanute, and most were on loan from the United States Air Force Museum . Other exhibits of note included a replica of the Wright 1903 Flyer, a large collection of Frasca Flight Simulators, and tributes to the veterans who have served in America's conflicts and wars. The museum closed on November 1, 2015. Chanute Air Force Base operated in Rantoul from 1917-1993. After decommission,

190-570: A honeycomb-shaped foil core. Expensive titanium would be used only in high-temperature areas like the leading edge of the horizontal stabilizer, and the nose. To cool the interior, the XB-70 pumped fuel en route to the engines through heat exchangers. On 30 August 1957, the Air Force decided that enough data were available on the NAA and Boeing designs that a competition could begin. On 18 September,

285-442: A chemical-fuel bomber with Mach 0.9 cruising speed and "maximum possible" speed during a 1,000-nautical-mile (1,200 mi; 1,900 km) entrance and exit from the target. The requirement also called for a 50,000-pound (23,000 kg) payload and a combat radius of 4,000 nautical miles (4,600 mi; 7,400 km). The Air Force formed similar requirements for a WS-110L intercontinental reconnaissance system in 1955, but this

380-428: A concept was technically feasible, but by March 1957, engine development and wind tunnel testing had progressed enough to suggest that it was. WS-110 was redesigned to fly at Mach 3 for the entire mission. Zip fuel was retained for the engine's afterburner to increase range. Both North American and Boeing returned new designs with very long fuselages and large delta wings. They differed primarily in engine layout;

475-455: A conventional jet engine, thrust is provided by heating air using jet fuel and accelerating it out a nozzle. In a nuclear engine, heat is supplied by a reactor, whose consumables last for months instead of hours. Most designs also carried a small amount of jet fuel for high-power portions of flight, such as takeoffs and high-speed dashes. Another possibility being explored at the time was the use of boron -enriched " zip fuels ", which increase

570-635: A cost of $ 40.8 million (equivalent to $ 50.8 million in 2023 ). On 28 February 2024, a tornado touched down in the Riverside area in Montgomery County, Ohio. The museum was struck by the tornado causing damage. The base commander, Col. Travis Pond, said that "the damage was isolated to the southern side of Area B. Damaged buildings included the Museum’s Restoration Hangar 4, Gate 22B, and other nearby facilities." The museum

665-556: A four-volume report on the B-70 that was published by NASA in April 1972. On 7 May 1965, a 3-foot (1 m) piece of the apex of the wing broke off in flight and caused extensive damage to five of the six engines. They were sent to GE and repaired. The sixth engine was inspected and re-installed in the aircraft. On 14 October 1965, AV-1 surpassed Mach 3, but heat and stress damaged the honeycomb panels, leaving 2 ft (60 cm) of

760-749: A laboratory building. In 1932, the collection was named the Army Aeronautical Museum and placed in a WPA building from 1935 until World War II. In 1948, the collection remained private as the Air Force Technical Museum. In 1954, the Air Force Museum became public and was housed in its first permanent facility, Building 89 of the former Patterson Field in Fairborn , which had been an engine overhaul hangar. Many of its aircraft were parked outside and exposed to

855-523: A lower altitude, the reflection of the ground would overwhelm the signal returned from a target. An interceptor flying at normal altitudes would be effectively blind to bombers far below it. The interceptor could descend to lower altitudes to increase the amount of visible sky, but doing so would limit its radar range in the same way as the missile sites, as well as greatly increasing fuel use and thus reducing mission time. The Soviet Union would not introduce an interceptor with look-down capability until 1972 with

950-492: A mid-air collision with an F-104 while flying in a multi-aircraft formation. Sonic boom and later testing continued with XB-70A #1. The second flight research program (NASA NAS4-1174) investigated "control of structural dynamics" from 25 April 1967 through the XB-70's last flight in 1969. At high altitude and high speed, the XB-70A experienced unwanted changes in altitude. NASA testing from June 1968 included two small vanes on

1045-406: A new stage, theater seats, and a new theater screen to support a broader range of programming—including educational presentations, live broadcasts and expanded documentary choices. It also included a 7.1 surround-sound system, audio devices for the hearing or visually impaired, and personal closed captioning systems. The Air Force Museum Foundation is a private, non-profit organization that supports

SECTION 10

#1732773208881

1140-473: A period of time before the radar systems were able to track the missile and start sending it guidance signals. With the SA-2 missile, this minimum altitude was roughly 2,000 feet (600 m). Flying at low level provided protection against fighters as well. Radars of the era did not have the ability to look down (see look-down/shoot-down ); if a higher altitude aircraft's radar was aimed down to detect targets at

1235-597: A smaller aircraft while flying in close formation; the remaining Valkyrie bomber is in the National Museum of the United States Air Force near Dayton, Ohio. In an offshoot of Boeing 's MX-2145 crewed boost-glide bomber project, Boeing hired RAND Corporation in January 1954 to explore what sort of bomber aircraft would be needed to deliver the various nuclear weapons under development. At

1330-428: A speed of Mach 3.05 while flying at 72,000 ft (22,000 m). AV-2 reached a top speed of Mach 3.08 and maintained it for 20 minutes on 12 April 1966. On 19 May 1966, AV-2 reached Mach 3.06 and flew at Mach 3 for 32 minutes, covering 2,400 mi (3,900 km) in 91 minutes of total flight. A joint NASA/USAF research program was conducted from 3 November 1966 to 31 January 1967 for measuring

1425-498: A time of gunpowder when we spoke of bombers in the missile age". In December 1959 the Air Force announced the B-70 project would be cut to a single prototype, and most of the planned B-70 subsystems would no longer be developed. Then interest increased due to the politics of presidential campaign of 1960 . A central plank of John F. Kennedy 's campaign was that Eisenhower and the Republicans were weak on defense, and pointed to

1520-507: Is SAM 26000 , a modified Boeing 707 known as a VC-137C , used regularly by presidents John F. Kennedy , Lyndon B. Johnson , and Richard Nixon . This aircraft took President and Mrs. Kennedy to Dallas on 22 November 1963—the day of the President's assassination. Vice President Johnson was sworn in as president aboard it shortly after the assassination, and the aircraft then carried Kennedy's body back to Washington, D.C. It became

1615-400: Is divided into galleries that cover broad historic trends in military aviation. These are further broken down into exhibits that detail specific historical periods and display aircraft in historical context. The museum's collection contains many rare aircraft of historical or technological importance, and various memorabilia and artifacts from the history and development of aviation. Among them

1710-507: Is line-of-sight, so aircraft could dramatically shorten detection distances by flying close to the Earth and hiding behind terrain. Missile sites spaced to overlap in range when attacking bombers at high altitudes would leave large gaps between their coverage for bombers flying at lower levels. With an appropriate map of the missile sites, the bombers could fly between and around the defenses. Additionally, early missiles generally flew unguided for

1805-698: Is the Apollo 15 Command Module Endeavour which orbited the Moon 74 times in 1971, one of four surviving Convair B-36 Peacemakers , the only surviving North American XB-70 Valkyrie and Bockscar —the Boeing B-29 Superfortress that dropped the Fat Man atomic bomb on Nagasaki during the last days of World War II . In 2010, the museum launched its 360-degree Virtual Tour , allowing most aircraft and exhibits to be viewed online. In 2018,

1900-719: Is the oldest and largest military aviation museum in the world, with more than 360 aircraft and missiles on display. The museum is a central component of the National Aviation Heritage Area . The museum draws about a million visitors each year, making it one of the most frequently visited tourist attractions in Ohio. The museum dates to 1923, when the Engineering Division at Dayton's McCook Field first collected technical artifacts for preservation. In 1927, it moved to then- Wright Field in

1995-595: The B-52 with the Mach ;2 top speed of the Convair B-58 Hustler . The new bomber was expected to enter service in 1963. Nuclear and conventional designs were considered. The nuclear-powered bomber was organized as " Weapon System 125A " and pursued simultaneously with the jet-powered version, "Weapon System 110A". The USAF Air Research and Development Command's (ARDC) requirement for WS-110A asked for

SECTION 20

#1732773208881

2090-583: The Boeing B-17F Memphis Belle was placed on permanent public display in the World War II Gallery. The aircraft and its crew became iconic symbols of the heavy bomber crews and support personnel who helped defeat Nazi Germany. The museum has several Presidential aircraft , including those used by Franklin D. Roosevelt , Harry Truman , and Dwight D. Eisenhower . The centerpiece of the presidential aircraft collection

2185-601: The Boeing B-47 Stratojet in the medium-range role. The Hustler was expensive to develop and purchase, and required enormous amounts of fuel and maintenance in comparison to the B-47. It was estimated that it cost three times as much to operate as the much larger and longer-ranged B-52. The B-70, designed for even higher speeds, altitudes and range than the B-58, suffered even more in relative terms. At high altitudes,

2280-569: The F-108 supersonic interceptor. To reduce program costs, the F-108 would share two of the engines, the escape capsule, and some smaller systems with the B-70. In early 1960, North American and the USAF released the first drawing of the XB-70 to the public. The B-70 was planned to use a high-speed, high-altitude bombing approach that followed a trend of bombers flying progressively faster and higher since

2375-719: The House Armed Services Committee (HASC) on 24 January 1962 that the B-70 was unjustifiable, LeMay subsequently argued for the B-70 to both the House and Senate committees—and was chastised by McNamara on 1 March. By 7 March 1962, the HASC, 21 of whose members had B-70 work in their districts, had written an appropriations bill to "direct"—by law—the Executive Branch to use all of the nearly $ 500 million (equivalent to $ 5 billion today) appropriated for

2470-748: The Northrop Grumman B-2 Spirit stealth bomber (test aircraft), the Lockheed F-117 Nighthawk stealth ground attack aircraft and others. The fourth building has four galleries,Presidential, Research and Development, Space and Global Reach, housing more than 70 aircraft, missiles, and space vehicles. Also in the fourth building is an enlarged educational outreach area with three science, technology, engineering and math (STEM) Learning Nodes. Previously these collections were housed in an annex facility on Area B of Wright-Patterson Air Force Base (the former Wright Field). Because

2565-583: The Soviet Union 's Tupolev Tu-144 SST program. The development of the Lockheed U-2 and the SR-71 Blackbird reconnaissance aircraft , as well as the XB-70, prompted Soviet aerospace engineers to design and develop their high-altitude and high-speed MiG-25 interceptor . The Valkyrie was designed to be a high-altitude Mach 3 bomber with six engines. Harrison Storms shaped

2660-410: The controllers could position their fighters in a suitable location for an interception. Its high speed made the aircraft difficult to see on radar displays and its high-altitude and high-speed capabilities could not be matched by any contemporaneous Soviet interceptor or fighter aircraft. The introduction of the first Soviet surface-to-air missiles in the late 1950s put the near-invulnerability of

2755-423: The energy density of jet fuel by about 40 percent, and could be used in modified versions of existing jet engine designs. Zip fuels appeared to offer sufficient performance improvement to produce a strategic bomber with supersonic speed. The Air Force followed these developments closely, and in 1955 issued General Operational Requirement No. 38 for a new bomber, combining the payload and intercontinental range of

2850-457: The Air Force issued operational requirements that called for a cruising speed of Mach 3.0 to 3.2, an over-target altitude of 70,000–75,000 ft (21,000–23,000 m), a range of up to 10,500 miles (16,900 km), and a gross weight not to exceed 490,000 pounds (220,000 kg). The aircraft would have to use the hangars, runways and handling procedures used by the B-52. On 23 December 1957,

2945-523: The Air Force's plan for the B-70 to reconnoiter and strike rail-mobile Soviet ICBMs, but the Chief of Staff of the Air Force , General Thomas White , admitted the Soviets would "be able to hit the B-70 with rockets" and requested the B-70 be downgraded to "a bare minimum research and development program" at $ 200 million for fiscal year 1960 (equivalent to $ 2.1 billion today). President Eisenhower responded that

Octave Chanute Aerospace Museum - Misplaced Pages Continue

3040-631: The B-70 as an example. He told a San Diego audience near NAA facilities, "I endorse wholeheartedly the B-70 manned aircraft." Kennedy also made similar campaign claims regarding other aircraft: near the Seattle Boeing plant he affirmed the need for B-52s and in Fort Worth he praised the B-58. The Air Force changed the program to full weapon development and awarded a contract for an XB-70 prototype and 11 YB-70s in August 1960. In November 1960,

3135-473: The B-70 in doubt. In response, the US Air Force (USAF) began flying its missions at low level, where the missile radar's line of sight was limited by terrain. In this low-level penetration role, the B-70 offered little additional performance over the B-52 it was meant to replace, while being far more expensive with shorter range. Alternative missions were proposed, but these were of limited scope. With

3230-473: The B-70 program received a $ 265 million (equivalent to $ 2.7 billion today) appropriation from Congress for FY 1961. Nixon, trailing in his home state of California, also publicly endorsed the B-70, and on 30 October Eisenhower helped the Republican campaign with a pledge of an additional $ 155 million ($ 1.6 billion today) for the B-70 development program. On taking office in January 1961, Kennedy

3325-478: The B-70 was as much as four times as fast as the B-52, but at low altitudes it was limited to only Mach 0.95, only modestly faster than the B-52 at the same altitudes. It also had a smaller bomb load and shorter range. Its only major advantage would be its ability to use high speed in areas without missile cover, especially on the long journey from the US to USSR. The value was limited; the USAF's doctrine stressed that

3420-588: The B-70 would add little performance for the high cost. After becoming the new Air Force Chief of Staff in July 1961, Curtis LeMay increased his B-70 advocacy, including interviews for August Reader's Digest and November Aviation Week articles, and allowing a 25 February General Electric tour at which the press was provided artist conceptions of, and other info about, the B-70. Congress had also continued B-70 appropriations to resurrect bomber development. After Secretary of Defense Robert McNamara explained again to

3515-621: The Champaign County Historical Archives for public access and research. Some aircraft remained onsite until 2018, when they were scrapped. United States Air Force Museum The National Museum of the United States Air Force (formerly the United States Air Force Museum ) is the official museum of the United States Air Force located at Wright-Patterson Air Force Base , six miles (9.7 km) northeast of Dayton, Ohio . The NMUSAF

3610-597: The High Lark radar in the MiG-23M , and even this model had very limited capability. Strategic Air Command found itself in an uncomfortable position; bombers had been tuned for efficiency at high speeds and altitudes, performance that had been purchased at great cost in both engineering and financial terms. Before the B-70 was to replace the B-52 in the long-range role, SAC had introduced the B-58 Hustler to replace

3705-623: The NAA design arranged its six engines in a semi-circular duct under the rear fuselage, while the Boeing design used separate podded engines located individually on pylons below the wing, like the Hustler. North American scoured available literature to find any additional advantage. This led them to an obscure report by two NACA wind tunnel experts, who wrote a report in 1956 titled "Aircraft Configurations Developing High Lift-Drag Ratios at High Supersonic Speeds". Known today as compression lift ,

3800-615: The North American proposal was declared the winner of the competition, and on 24 January 1958, a contract was issued for Phase 1 development. In February 1958, the proposed bomber was designated B-70 , with the prototypes receiving the "X" experimental prototype designation . The name " Valkyrie " was the winning submission in early 1958, selected from 20,000 entries in a USAF "Name the B-70" contest. The Air Force approved an 18-month program acceleration in March 1958 that rescheduled

3895-490: The RS-70 (see Variants ). McNamara was unsuccessful with an address to the HASC on 14 March, but a 19 March 1962 11th hour White House Rose Garden agreement between Kennedy and HASC chairman Carl Vinson retracted the bill's language and the bomber remained canceled. The XB-70s were intended to be used for the advanced study of aerodynamics , propulsion , and other subjects related to large supersonic transports. The crew

Octave Chanute Aerospace Museum - Misplaced Pages Continue

3990-576: The Space Gallery, Presidential Aircraft Gallery, and Global Reach Gallery. With the additional space, more than 70 aircraft that were in storage have been put back on display, such as the XB-70 Valkyrie . The Presidential Aircraft collection is also back on site, having been moved to an outside location for some time. The Air Force Museum Foundation funded the construction entirely with private donations from several different sources at

4085-620: The United States. Most of these loaned aircraft duplicate aircraft exhibited by the museum. These other aircraft remain the property of the Department of the Air Force and are typically identified at these locations as being "On Loan from the National Museum of the U.S. Air Force." The museum's staff has very high standards for the restoration and quality of care of loaned assets and has, in the past, revoked these loans when it

4180-610: The Wrights' 1909 Military Flyer is on display, as well as other Wright brothers artifacts. The building also hosts the National Aviation Hall of Fame , which includes several educational exhibits. The museum has many pieces of U.S. Army Air Forces and U.S. Air Force clothing and uniforms. At any time, more than 50 World War II-vintage A-2 leather flying jackets are on display, many of which belonged to famous figures in Air Force history. Others are painted to depict

4275-547: The advent of intercontinental ballistic missiles (ICBMs) during the late 1950s, crewed nuclear bombers were increasingly seen as obsolete. The USAF eventually gave up fighting for its production and the B-70 program was cancelled in 1961. Development was then turned over to a research program to study the effects of long-duration high-speed flight. As a result, two prototype aircraft, designated XB-70A, were built; these aircraft were used for supersonic test-flights from 1964 to 1969. In 1966, one prototype crashed after colliding with

4370-460: The aircraft with a canard surface and a delta wing , which was built largely of stainless steel , sandwiched honeycomb panels, and titanium . The XB-70 was designed to use supersonic technologies developed for the Mach 3 SM-64 Navaho , as well as a modified form of the Navaho's inertial guidance system. The XB-70 used compression lift , which resulted from a shock wave generated by

4465-446: The aircraft to maintain directional stability at high speeds. NAA's solution had an additional advantage, as it decreased the surface area of the rear of the wing when the panels were moved into their high-speed position. This helped offset the natural rearward shift of the center of pressure , or "average lift point", with increasing speeds. Under normal conditions this caused an increasing nose-down trim, which had to be offset by moving

4560-537: The airplane to a base in Alabama . On 23 April 2015, it was announced that the museum would be closing due to lack of funds on December 30 of that year. However, the closing date was later moved up and the museum closed on November 1. Some of the exhibits went to other museums in the state of Illinois. In 2016, the museum’s archival records, including blueprints, maps, publications, oral histories, photographs, scrapbooks, videotapes, and administrative records, were sent to

4655-470: The airplanes and missions flown by their former owners. The displays include the jacket worn by Brigadier General James Stewart , P-38 ace Major Richard I. Bong 's sheepskin B-3 jacket and boots, an A-2 jacket worn by one of the few USAAF pilots to leave the ground during the attack on Pearl Harbor , and President Ronald Reagan 's USAAF peacoat . The third building houses post- Cold War era planes such as

4750-541: The annex was physically located on the base itself, museum guests were required to go through additional security checks before taking museum buses to the hangar. The museum owns other USAF aircraft, including former U.S. Army Air Service , USAAC or USAAF aircraft, that are on loan to other aerospace museums in the United States and overseas, as well as those on permanent static display at various U.S. Air Force installations and tenant activities worldwide, and at Air Force Reserve and Air National Guard installations across

4845-603: The backup presidential aircraft after Nixon's first term. It was temporarily removed from display on 5 December 2009, repainted and returned to display on President's Day in 2010. All presidential aircraft are now displayed in the Presidential Gallery, in the fourth building. A large section of the museum is dedicated to pioneers of flight, especially the Wright Brothers , who conducted some of their experiments at nearby Huffman Prairie . A replica of

SECTION 50

#1732773208881

4940-407: The cleanup and conversion of the 2,125-acre (8.60 km) grounds began. Economic redevelopment of the former base was a paramount concern to the surrounding community. As of 2008, portions of the site are still unoccupied, due in part to environmental concerns including asbestos contamination. Nevertheless, much has been repurposed into civilian concerns. The Octave Chanute Aerospace Museum was one of

5035-639: The control surfaces, increasing drag . When the wing tips were drooped, the lifting area of the wings was lessened, moving the lift forward and reducing trim drag . The buildup of heat due to skin friction during sustained supersonic flight had to be addressed. During a Mach 3 cruise, the aircraft would reach an average of 450 °F (230 °C), with leading edges reaching 630 °F (330 °C), and up to 1,000 °F (540 °C) in engine compartments. NAA proposed building their design out of sandwich panels , with each panel consisting of two thin sheets of stainless steel brazed to opposite faces of

5130-549: The designs, and in September 1956 deemed them too large and complicated for operations. General Curtis LeMay was dismissive, declaiming, "This is not an airplane, it's a three-ship formation." The USAF ended Phase 1 development in October 1956 and instructed the two contractors to continue design studies. While the original proposals were being studied, advances in supersonic flight were proceeding rapidly. The narrow delta

5225-597: The difference. Most of the range lost in the change from zip fuel was restored by filling one of the two bomb bays with a fuel tank. Another problem arose when the XF-108 program was canceled in September 1959, which ended the shared development that benefited the B-70 program. At two secret meetings on 16 and 18 November 1959, the Chairman of the Joint Chiefs of Staff , Air Force General Nathan Twining , recommended

5320-508: The earliest efforts, opening in 1994. The museum was located in Grissom Hall, which functioned as the missile maintenance training facility during active Air Force operations. Until base closure in 1993, all Air Force Minuteman missile maintenance training was provided at Chanute. The building has largely been preserved and was restored to its condition at the time of base closure; four authentic Minuteman training silos were displayed at

5415-423: The engines, better positioning the shock in relation to the wing. The six individually-podded engines were repositioned, three in each of two separate ducts, under the fuselage. North American improved on the basic concept by adding a set of drooping wing-tip panels that were lowered at high speed. This helped trap the shock wave under the wing between the downturned wing tips. It also added more vertical surface to

5510-562: The engines. To reduce the likelihood of autoignition , nitrogen was injected into the JP-6 during refueling, and the "fuel pressurization and inerting system " vaporized a 700-pound (320 kg) supply of liquid nitrogen to fill the fuel tank vent space and maintain tank pressure. The XB-70's maiden flight was on 21 September 1964. In the first flight test, between Palmdale and Edwards AFB, one engine had to be shut down shortly after take-off, and an undercarriage malfunction warning meant that

5605-400: The first flight to December 1961. But in late 1958 the service announced that this acceleration would not be possible due to lack of funding. In December 1958, a Phase II contract was issued. The mockup of the B-70 was reviewed by the Air Force in March 1959. Provisions for air-to-surface missiles and external fuel tanks were requested afterward. At the same time, North American was developing

5700-420: The fixed cockpit windshield. With the ramp raised into its high-speed position, the forebody was more streamlined. Rain removal and windshield anti-ice was accomplished by utilizing 600 °F (320 °C) bleed air from the engines. The lower forward section included a radar bay, and production machines were to be equipped with a refueling receptacle on the upper surface of the forward fuselage. The XB-70

5795-617: The flight was flown with the undercarriage down as a precaution, limiting speed to 390 mph (630 km/h) – about half that planned. During landing, the rear wheels of the port side main gear locked, the tires ruptured, and a fire started. The Valkyrie first became supersonic (Mach 1.1) on the third test flight on 12 October 1964, and flew above Mach 1 for 40 minutes during the following flight on 24 October. The wing tips were also lowered partially in this flight. XB-70 No. 1 surpassed Mach 3 on 14 October 1965 by reaching Mach 3.02 at 70,000 ft (21,000 m). The first aircraft

SECTION 60

#1732773208881

5890-786: The formation. After the photoshoot, the F-104 drifted into the XB-70's right wingtip, flipped and rolled inverted over the top of the Valkyrie, before striking the bomber's vertical stabilizers and left wing. The F-104 then exploded, destroying the Valkyrie's vertical stabilizers and damaging its left wing. Despite the loss of both vertical stabilizers and damage to the wings, the Valkyrie flew straight for 16 seconds before it entered an uncontrollable spin and crashed north of Barstow, California . NASA Chief Test Pilot Joe Walker (F-104 pilot) and Carl Cross (XB-70 co-pilot) were killed. Al White (XB-70 pilot) ejected, sustaining serious injuries, including

5985-465: The fuel turned into caustic and abrasive liquids and solids that increased wear on moving turbine engine components and were toxic, making servicing difficult. Although the B-70 was intended to use zip only in the afterburners, and thus avoid this problem, the enormous cost of the zip program for such limited gains led to its cancellation. This by itself was not a fatal problem as newly developed high-energy fuels like JP-6 were available to make up some of

6080-437: The idea was to use the shock wave generated off the nose or other sharp points on the aircraft as a source of high-pressure air. By carefully positioning the wing in relation to the shock, the shock's high pressure could be captured on the bottom of the wing and generate additional lift. To take maximum advantage of this effect, they redesigned the underside of the aircraft to feature a large triangular intake area far forward of

6175-561: The intensity and signature of sonic booms for the National Sonic Boom Program. Testing was planned to cover a range of sonic boom overpressures on the ground similar to but higher than those anticipated from the proposed American SST . In 1966, AV-2 was selected for the program and was outfitted with test sensors. It flew the first sonic boom test on 6 June 1966, attaining a speed of Mach 3.05 at 72,000 ft (22,000 m). Two days later, AV-2 crashed following

6270-399: The leading edge of the engine intake splitter below the apex of the wing. At Mach 3 cruising speed, the shock wave is bent back about 65 degrees and the wing is superimposed on the shock system which has a pressure 40 pounds per square foot (1.9 kPa) higher under the aircraft than in front of the shock. The compression lift provided five percent of the total lift. Camber was added to

6365-445: The leading edge of the left wing missing. The first aircraft was limited to Mach 2.5 afterwards. On 8 June 1966, XB-70A No. 2 was in close formation with four other aircraft (an F-4 Phantom , an F-5 , a T-38 Talon , and an F-104 Starfighter ) for a photoshoot at the behest of General Electric, manufacturer of the engines of all five aircraft. A sixth aircraft, a Learjet 23 , had been contracted by General Electric to photograph

6460-617: The mission and goals of the National Museum of the U.S. Air Force. XB-70 Valkyrie The North American Aviation XB-70 Valkyrie is a retired prototype version of the planned B-70 nuclear -armed, deep-penetration supersonic strategic bomber for the United States Air Force Strategic Air Command . Designed in the late 1950s by North American Aviation (NAA) to replace the B-52 Stratofortress and B-58 Hustler ,

6555-488: The museum has more than tripled in square footage since 1971, with the addition of a second hangar in 1988, a third in 2003, and a fourth in 2016. In October 2004, the name changed from United States Air Force Museum to National Museum of the United States Air Force. In June 2016, the museum open its 224,000-square-foot (20,800 m ) fourth building that expanded the museum to the current 1,120,000 square feet (104,000 m ) of exhibit space. The fourth building houses

6650-416: The museum. The museum was administered under the direction of a private foundation. Efforts to found a museum started as early as 1991, after it was recognized that the closure of the base would cause the dispersal of the aircraft on display there. A few months before it opened on 8 October 1994, the museum was involved in a dispute over the display of a B-25 . The United States Air Force wanted to transfer

6745-445: The nose of AV-1 for measuring the response of the aircraft's stability augmentation system. AV-1 flew a total of 83 flights. The XB-70's last supersonic flight took place on 17 December 1968. On 4 February 1969, AV-1 took its final flight to Wright-Patterson Air Force Base for museum display (now the National Museum of the United States Air Force ). Flight data was collected on this subsonic trip. North American Rockwell completed

6840-453: The primary reason for maintaining the bomber force in an era of ICBMs was that the bombers could remain in the air at long ranges from their bases and were thus immune to sneak attack. In this case, the higher speed would be used for only a short period of time between the staging areas and the Soviet coastline. Adding to the problems, the zip fuel program was canceled in 1959. After burning,

6935-489: The problem of flying at three times the speed of sound with an airframe potentially useful as a bomber." After Congress approved $ 290 million ($ 3 billion today) of B-70 "add-on" funds to the President's 12 May 1960 modified FY 1961 budget, the Administration decided on a "Planned Usage" of only $ 100 million ($ 1,020 million today) of these funds. The Department of Defense subsequently presented data to Congress that

7030-473: The reconnaissance and strike mission was "crazy" since the nuclear mission was to attack known production and military complexes, and emphasized that he saw no need for the B-70 since the ICBM is "a cheaper, more effective way of doing the same thing". Eisenhower also identified that the B-70 would not be in manufacturing until "eight to ten years from now" and "said he thought we were talking about bows and arrows at

7125-426: The shock originating at the intake splitter to reflect from the vertical tip surface giving additional compression lift. Like a number of other delta-wing aircraft designed for supersonic speeds (Concorde, Tu-144, FD2), the Valkyrie needed a feature to improve the pilot's view during nose-high low-speed flight and on the ground. An outer windshield and ramp, which could be lowered, was provided enabling viewing through

7220-408: The six-engine, delta-winged Valkyrie could cruise for thousands of miles at Mach 3+ while flying at 70,000 feet (21,000 m). At these speeds, it was expected that the B-70 would be practically immune to interceptor aircraft , the only effective weapon against bomber aircraft at the time. The bomber would spend only a brief time over a particular radar station, flying out of its range before

7315-459: The size of the AAA weapons needed to reach those altitudes. As early as 1942, German flak commanders had already concluded that AAA would be essentially useless against jet aircraft, and began development of guided missiles to fill this role. Most forces reached the same conclusion soon afterwards, with both the US and UK starting missile development programs before the war ended. The UK's Green Mace

7410-414: The start of crewed bomber use. Through that same period, only two weapons proved effective against bombers: fighter aircraft and anti-aircraft artillery (AAA). Flying higher and faster made it more difficult for both; higher speeds allowed the bomber to fly out of range of the weapons more quickly, while higher altitudes increased the time needed for fighters to climb to the bombers, and greatly increased

7505-406: The time needed to get the pilot into the cockpit of a fighter. Guidance did not require wide-area tracking or calculation of an intercept course: a simple comparison of the time needed to fly to the altitude of the target returned the required deflection . Missiles also had greater altitude capability than any aircraft and improving this to adapt to new aircraft was a low-cost development path. The US

7600-459: The time, nuclear weapons weighed several tons, and the need to carry enough fuel to fly that payload from the continental United States to the Soviet Union demanded large bombers. Boeing and RAND also concluded that the aircraft would need supersonic speed to escape the blast of its bombs. The aviation industry had been studying this problem for some time. From the mid-1940s, there was interest in using nuclear-powered aircraft as bombers. In

7695-541: The weather. Through the 1960s, Eugene Kettering, son of Charles F. Kettering , led the project to build a permanent structure to house the collections and became the first chairman of the board of the Air Force Museum Foundation. When he died in 1969, his widow Virginia took over the project. Her "determination, logic and meticulous attention" kept it on track, and the current facility opened in 1971. Not including its annex on Wright Field proper,

7790-404: The wing leading edge inboard of the folding tips to improve subsonic handling and reduce supersonic drag. The outer portions of the wings were hinged to pivot downward by 65 degrees, acting as a type of variable-geometry wingtip device . This increased the aircraft's directional stability at supersonic speeds, shifted the center of pressure to a more favorable position at high speeds, and caused

7885-683: Was aware of Soviet work in the field, and had reduced the expected operational lifetime of the U-2, knowing that it would become vulnerable to these missiles as they were improved. In 1960, a U-2 flown by Gary Powers was shot down by one of the earliest Soviet guided air-defence missiles, the S-75 Dvina , known in the west as the SA-2 Guideline. Faced with this problem, military doctrine had already started shifting away from high-altitude supersonic bombing toward low-altitude penetration . Radar

7980-473: Was completed on 15 October 1964. The manufacture of the third prototype (AV-3) was canceled in July 1964 before completion. The first XB-70 carried out its maiden flight in September 1964 and many more test flights followed. The data from the XB-70 test flights and aerospace materials development were used in the later B-1 bomber program , the American supersonic transport (SST) program, and via espionage,

8075-514: Was deemed that these other museums did not have the resources to properly care for an artifact. This happened in the case of the famous Boeing B-17 Flying Fortress , Memphis Belle . For an additional fee, guests can view aviation- and space-oriented films in a large format theater interspersed primarily with other documentaries. In 2013, the Air Force Museum Theater was upgraded from IMAX to digital 3D. The renovation included

8170-554: Was depleted before a supersonic dash to the target. The tanks also included the outer portions of the wing, which would also be jettisoned to produce a smaller wing suitable for supersonic speeds. Both became trapezoidal wings after ejection, at that time the highest performance planform known. They also featured flush cockpits to maintain the highest fineness ratio possible in spite of its effects on visibility. The two designs had takeoff weights of about 750,000 pounds (340,000 kg) with large fuel loads. The Air Force evaluated

8265-423: Was equipped with six General Electric YJ93 -GE-3 turbojet engines, which used JP-6 jet fuel, specially formulated for the mission requirements. The engine was stated to be in the "30,000-pound class", but actually produced 28,000 lbf (120 kN) with afterburner and 19,900 lbf (89 kN) without afterburner. The Valkyrie used fuel for cooling; it was pumped through heat exchangers before reaching

8360-484: Was establishing itself as a preferred planform for supersonic flight, replacing earlier designs like the swept-wing and trapezoidal layouts seen on designs like the Lockheed F-104 Starfighter and the earlier WS-110 concepts. Engines able to cope with higher temperatures were also under development, allowing for sustained supersonic speeds. This work led to an interesting discovery: when an engine

8455-461: Was found to suffer from weaknesses in the honeycomb panels, primarily due to inexperience with fabrication and quality control of this new material. On two occasions, honeycomb panels failed and were torn off during supersonic flight, necessitating a Mach 2.5 limit being placed on the aircraft. The deficiencies discovered on AV-1 were almost completely solved on the second XB-70, which first flew on 17 July 1965. On 3 January 1966, XB-70 No. 2 attained

8550-413: Was informed that the missile gap was an illusion. On 28 March 1961, after $ 800 million (equivalent to $ 8.2 billion today) had been spent on the B-70 program, Kennedy canceled the project as "unnecessary and economically unjustifiable" because it "stood little chance of penetrating enemy defenses successfully." Instead, Kennedy recommended "the B-70 program be carried forward essentially to explore

8645-513: Was later canceled in 1958 due to better options. In July 1955, six contractors were selected to bid on WS-110A studies. Boeing and North American Aviation submitted proposals, and on 8 November 1955 were awarded contracts for Phase 1 development. In mid-1956, initial designs were presented by the two companies. Zip fuel was to be used in the afterburners to improve range by 10 to 15 percent over conventional fuel. Both designs had huge wing-tip fuel tanks that could be jettisoned when their fuel

8740-452: Was later discovered that flying faster also made radar detection much more difficult due to an effect known as the blip-to-scan ratio , and any reduction in tracking efficiency would further interfere with the operation and guidance of fighters. The introduction of the first effective anti-aircraft missiles by the late 1950s changed this picture dramatically. Missiles could stand ready for immediate launch, eliminating operational delays like

8835-457: Was one of the last attempts to develop a useful high-altitude AAA weapon, but its development ended in 1957. Interceptor aircraft with ever-improving performance remained the only effective anti-bomber weapons by the early 1950s, and even these were having problems keeping up with the latest designs; Soviet interceptors during the late 1950s could not intercept the high-altitude U-2 reconnaissance aircraft, despite its relatively low speeds. It

8930-517: Was optimized specifically for high speed, it burned perhaps twice as much fuel at that speed than when it was running at subsonic speeds. However, the aircraft would be flying as much as four times as fast. Thus its most economical cruise speed, in terms of fuel per mile, was its maximum speed. This was entirely unexpected and implied that there was no point in the dash concept; if the aircraft was able to reach Mach 3, it may as well fly its entire mission at that speed. The question remained whether such

9025-539: Was reduced to only the two pilots, as a navigator and a bombardier were not needed for this research role. The production order was reduced to three prototypes in March 1961 with the third aircraft to incorporate improvements from the previous prototype. The order was later reduced to two experimental XB-70As, named Air Vehicle 1 and 2 (AV-1 and AV-2). XB-70 No. 1 was completed on 7   May 1964, and rolled out on 11   May 1964 at Palmdale, California . One report stated "nothing like it existed anywhere". AV-2

#880119