89-465: The Boeing CIM-10 Bomarc ("Boeing Michigan Aeronautical Research Center") ( IM-99 Weapon System prior to September 1962) was a supersonic ramjet powered long-range surface-to-air missile (SAM) used during the Cold War for the air defense of North America. In addition to being the first operational long-range SAM and the first operational pulse doppler aviation radar, it was the only SAM deployed by
178-400: A convergent–divergent nozzle . Although ramjets have been run as slow as 45 metres per second (160 km/h; 100 mph), below about Mach 0.5 (170 m/s; 610 km/h; 380 mph) they give little thrust and are highly inefficient due to their low pressure ratios. Above this speed, given sufficient initial flight velocity, a ramjet is self-sustaining. Unless the vehicle drag
267-763: A long-range antipodal bomber , similar to the Sänger-Bredt bomber , but powered by ramjet instead of rocket. In 1954, NPO Lavochkin and the Keldysh Institute began development of a Mach 3 ramjet-powered cruise missile, Burya . This project competed with the R-7 ICBM developed by Sergei Korolev , but was cancelled in 1957. Several ram jets were designed, built, and ground-tested at the Kawasaki Aircraft Company's facility in Gifu during
356-434: A pitot -type opening for the inlet. This is followed by a widening internal passage (subsonic diffuser) to achieve a lower subsonic velocity that is required at the combustor. At low supersonic speeds a normal (planar) shock wave forms in front of the inlet. For higher supersonic speeds the pressure loss through the shock wave becomes prohibitive and a protruding spike or cone is used to produce oblique shock waves in front of
445-409: A turbine , which generates its own compressed air (i.e. ram air in a ramjet) in order to generate thrust. The diffuser converts the high velocity of the air approaching the intake into high (static) pressure required for combustion. High combustion pressures minimise entropy rise during heat addition, this minimising wasted thermal energy in the exhaust gases Subsonic and low-supersonic ramjets use
534-477: A Bomarc B successfully intercepted a Regulus II cruise missile flying at 100,000 ft (30,000 m), thus achieving the highest interception in the world up to that date. Boeing built 570 Bomarc missiles between 1957 and 1964, 269 CIM-10A, 301 CIM-10B. In September 1958 Air Research & Development Command decided to transfer the Bomarc program from its testing at Cape Canaveral Air Force Station to
623-510: A combustor exit stagnation temperature of the order of 2,400 K (2,130 °C; 3,860 °F) for kerosene . Normally, the combustor must be capable of operating over a wide range of throttle settings, matching flight speeds and altitudes. Usually, a sheltered pilot region enables combustion to continue when the vehicle intake undergoes high yaw/pitch during turns. Other flame stabilization techniques make use of flame holders, which vary in design from combustor cans to flat plates, to shelter
712-429: A compact mechanism for high-speed, such as missiles . Weapons designers are investigating ramjet technology for use in artillery shells to increase range; a 120 mm ramjet-assisted mortar shell is thought to be able to travel 35 km (22 mi). They have been used, though not efficiently, as tip jets on the ends of helicopter rotors. L'Autre Monde: ou les États et Empires de la Lune ( Comical History of
801-416: A cruising altitude of 60,000 feet (18,000 m). It was 46.6 ft (14.2 m) long and weighed 15,500 pounds (7,000 kg). Its armament was either a 1,000-pound (450 kg) conventional warhead or a W40 nuclear warhead (7–10 kiloton yield). A liquid-fuel rocket engine boosted the Bomarc to Mach 2, when its Marquardt RJ43-MA-3 ramjet engines, fueled by 80-octane gasoline, would take over for
890-548: A few remain on display today. During World War II , the US Army Air Force (USAAF) concluded that existing anti-aircraft guns , only marginally effective against existing generations of propeller-driven aircraft, would not be effective at all against the emerging jet-powered designs. Like the Germans and British before them, they concluded the only successful defence would be to use guided weapons. As early as 1944
979-414: A final normal shock that occurs at the inlet entrance lip. The diffuser in this case consists of two parts, the supersonic diffuser, with shock waves external to the inlet, followed by the internal subsonic diffuser. At higher speeds still, part of the supersonic diffusion has to take place internally, requiring external and internal oblique shock waves. The final normal shock has to occur in the vicinity of
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#17327875537121068-462: A hot fuel-rich gas which is burnt in the ramcombustor with the compressed air supplied by the intake(s). The flow of gas improves the mixing of the fuel and air and increases total pressure recovery. In a throttleable ducted rocket, also known as a variable flow ducted rocket, a valve allows the gas generator exhaust to be throttled allowing thrust control. Unlike an LFRJ, solid propellant ramjets cannot flame out . The ducted rocket sits somewhere between
1157-462: A minimum flow area known as the throat, which is followed by the subsonic diffuser. As with other jet engines, the combustor raises the air temperature by burning fuel. This takes place with a small pressure loss. The air velocity entering the combustor has to be low enough such that continuous combustion can take place in sheltered zones provided by flame holders . A ramjet combustor can safely operate at stoichiometric fuel:air ratios. This implies
1246-502: A moderately successful Canadian pop group, The Beau Marks . Aircraft of comparable role, configuration, and era Ramjet A ramjet is a form of airbreathing jet engine that requires forward motion of the engine to provide air for combustion. Ramjets work most efficiently at supersonic speeds around Mach 3 (2,300 mph; 3,700 km/h) and can operate up to Mach 6 (4,600 mph; 7,400 km/h). Ramjets can be particularly appropriate in uses requiring
1335-529: A modified Polikarpov I-15 . Merkulov designed a ramjet fighter "Samolet D" in 1941, which was never completed. Two of his DM-4 engines were installed on the Yak-7 PVRD fighter during World War II. In 1940, the Kostikov-302 experimental plane was designed, powered by a liquid fuel rocket for take-off and ramjet engines for flight. That project was cancelled in 1944. In 1947, Mstislav Keldysh proposed
1424-575: A new facility on Santa Rosa Island , south of Eglin AFB Hurlburt Field on the Gulf of Mexico . To operate the facility and to provide training and operational evaluation in the missile program, Air Defense Command established the 4751st Air Defense Wing (Missile) (4751st ADW) on 15 January 1958. The first launch from Santa Rosa took place on 15 January 1959. In 1955, to support a program which called for 40 squadrons of BOMARC (120 missiles to
1513-410: A nozzle to accelerate it to supersonic speeds and generate forward thrust . Ramjets are much less complex than turbojets or turbofans , requiring only an air intake, a combustor, and a nozzle to be built. Additionally, ramjets have little to no moving parts - liquid-fuel ramjets have only a fuel pump, whilst solid-fuel ramjets lack even this. By comparison, a turbojet uses a compressor driven by
1602-572: A range of about 105 kilometres (65 miles). It was also used as a surface-to-surface weapon and was modified to destroy land-based radars. Using technology proven by the AQM-60, In the late 1950s and early 1960s the US produced a widespread defense system called the CIM-10 Bomarc , which was equipped with hundreds of nuclear armed ramjet missiles with a range of several hundred miles. It was powered by
1691-647: A reality in the mid-1950s, the USAF began to develop a new solid-fueled Bomarc variant, the IM-99B Bomarc ;B. It used a Thiokol XM51 booster, and also had improved Marquardt RJ43-MA-7 (and finally the RJ43-MA-11) ramjets. The first IM-99B was launched in May 1959, but problems with the new propulsion system delayed the first fully successful flight until July 1960, when a supersonic MQM-15A Regulus II drone
1780-525: A solid fuel ramjet (SFRJ) vehicle test in August 2022. In 2023, General Electric demonstrated a ramjet with rotating detonation combustion. It is a turbine-based combined-cycle engine that incorporates a In the late 1950s, 1960s, and early 1970s, the UK developed several ramjet missiles. The Blue Envoy project was supposed to equip the country with a long range ramjet powered air defense against bombers, but
1869-593: A special test rig on a Dornier Do 17 Z at flight speeds of up to 200 metres per second (720 km/h). Later, as petrol became scarce in Germany, tests were carried out with blocks of pressed coal dust as a fuel (see e.g. Lippisch P.13a ), which were not successful due to slow combustion. Stovepipe (flying/flaming/supersonic) was a popular name for the ramjet during the 1950s in trade magazines such as Aviation Week & Space Technology and other publications such as The Cornell Engineer. The simplicity implied by
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#17327875537121958-488: A speed of Mach 3. It was used successfully in combat against multiple types of aircraft during the Falklands War . Eminent Swiss astrophysicist Fritz Zwicky was research director at Aerojet and holds many patents in jet propulsion. Patents US 5121670 and US 4722261 are for ram accelerators . The U.S. Navy would not allow Zwicky to publicly discuss his invention, US 2461797
2047-408: A squadron for a total of 4,800 missiles), ADC reached a decision on the location of these 40 squadrons and suggested operational dates for each. The sequence was as follows: ... l. McGuire 1/60 2. Suffolk 2/60 3. Otis 3/60 4. Dow 4/60 5. Niagara Falls 1/61 6. Plattsburgh 1/61 7. Kinross 2/61 8. K.I. Sawyer 2/61 9. Langley 2/61 10. Truax 3/61 11. Paine 3/61 12. Portland 3/61 ... At
2136-633: A supersonic manned interceptor aircraft, arguing that the missile program made the Arrow unnecessary. Initially, it was unclear whether the missiles would be equipped with nuclear warheads. By 1960 it became known that the missiles were to have a nuclear payload, and a debate ensued about whether Canada should accept nuclear weapons. Ultimately, the Diefenbaker government decided that the Bomarcs should not be equipped with nuclear warheads. The dispute split
2225-439: A tandem arrangement. Integrated boosters provide a more efficient packaging option, since the booster propellant is cast inside the otherwise empty combustor. This approach has been used on solid-fuel ramjets (SFRJ), for example 2K12 Kub , liquid, for example ASMP , and ducted rocket, for example Meteor , designs. Integrated designs are complicated by the different nozzle requirements of the boost and ramjet flight phases. Due to
2314-543: Is extremely high, the engine/airframe combination tends to accelerate to higher and higher flight speeds, substantially increasing the air intake temperature. As this could damage the engine and/or airframe integrity, the fuel control system must reduce fuel flow to stabilize speed and, thereby, air intake temperature. Due to the stoichiometric combustion temperature, efficiency is usually good at high speeds (around Mach 2 – Mach 3, 680–1,000 m/s, 2,500–3,700 km/h, 1,500–2,300 mph), whereas at low speeds
2403-557: Is for the Underwater Jet, a ram jet that performs in a fluid medium. Time magazine reported on Zwicky's work. The first part of a ramjet is its diffuser (compressor) in which the forward motion of the ramjet is used to raise the pressure of its working fluid (air) as required for combustion. Air is compressed, heated by combustion and expanded in a thermodynamic cycle known as the Brayton cycle , before being passed through
2492-412: Is through ablation of the propellant by the hot compressed air from the intake(s). An aft mixer may be used to improve combustion efficiency . SFIRRs are preferred over LFRJs for some applications because of the simplicity of the fuel supply, but only when the throttling requirements are minimal, i.e. when variations in altitude or speed are limited. In a ducted rocket, a solid fuel gas generator produces
2581-500: The Atomic Energy Commission cleaned up the site and covered it with concrete. This was the only major incident involving the weapon system. The site remained in operation for several years following the fire. Since its closure in 1972, the area has remained off limits, primarily due to low levels of plutonium contamination. Between 2002 and 2004, 21,998 cubic yards of contaminated debris and soils were shipped to what
2670-485: The Austro-Hungarian Army , but the proposal was rejected. After World War I, Fonó returned to the subject. In May 1928 he described an "air-jet engine" which he described as suitable for high-altitude supersonic aircraft, in a German patent application. In an additional patent application, he adapted the engine for subsonic speed. The patent was granted in 1932 (German Patent No. 554,906, 1932-11-02). In
2759-562: The Leduc 0.10 was one of the first ramjet-powered aircraft to fly, in 1949. The Nord 1500 Griffon reached Mach 2.19 (745 m/s; 2,680 km/h) in 1958. In 1915, Hungarian inventor Albert Fonó devised a solution for increasing the range of artillery , comprising a gun-launched projectile united with a ramjet propulsion unit, thus giving a long range from relatively low muzzle velocities, allowing heavy shells to be fired from relatively lightweight guns. Fonó submitted his invention to
CIM-10 Bomarc - Misplaced Pages Continue
2848-640: The Lockheed D-21 spy drone. In the late 1950s the US Navy introduced a system called the RIM-8 Talos , which was a long range surface-to-air missile fired from ships. It successfully shot down enemy fighters during the Vietnam War , and was the first ship-launched missile to destroy an enemy aircraft in combat. On 23 May 1968, a Talos fired from USS Long Beach shot down a Vietnamese MiG at
2937-517: The United States Air Force . Stored horizontally in a launcher shelter with a movable roof, the missile was erected, fired vertically using rocket boosters to high altitude, and then tipped over into a horizontal Mach 2.5 cruise powered by ramjet engines. This lofted trajectory allowed the missile to operate at a maximum range as great as 430 mi (690 km). Controlled from the ground for most of its flight, when it reached
3026-516: The United States Army started exploring anti-aircraft missiles, examining a variety of concepts. At the time, two basic concepts appeared possible; one would use a short-range rocket that flew directly at the target from below following a course close to the line-of-sight, and the other would fly up to the target's altitude and then tip over and fly horizontally towards the target like a fighter aircraft . As both concepts seemed promising,
3115-623: The 1960s, in spite of Air Force claims to the contrary. As testing continued, the Air Force reduced its plans to sixteen sites, and then again to eight with an additional two sites in Canada. The first US site was declared operational in 1959, but with only a single working missile. Bringing the rest of the missiles into service took years, by which time the system was obsolete. Deactivations began in 1969 and by 1972 all Bomarc sites had been shut down. A small number were used as target drones, and only
3204-513: The 4751st Air Defense Squadron (Missile) remained at Hurlburt and Santa Rosa Island for training purposes. In 1964, the liquid-fueled Bomarc-A sites and squadrons began to be deactivated. The sites at Dow and Suffolk County closed first. The remainder continued to be operational for several more years while the government started dismantling the air defense missile network. Niagara Falls was the first BOMARC B installation to close, in December 1969;
3293-534: The Air Force to begin a lengthy series of attacks on the Army in the press, a common occurrence at the time known as " policy by press release ". When the Army released its first official information on Ajax to the press, the Air Force responded by leaking information on BOMARC to Aviation Week , and continued to denigrate Nike in the press over the next few years, in one case showing a graphic of Washington being destroyed by nuclear bombs that Ajax failed to stop. Tests of
3382-607: The Army Air Force was given the task of developing the airplane-like design, while the Army Ordnance Department was given the more ballistic collision-course concept. Official requirements were published in 1945. Official requirements were published in 1945; Bell Laboratories won the Ordnance contract for a short-range line-of-sight weapon under Project Nike, while a team of players led by Boeing won
3471-472: The Army was beginning to develop its much more powerful successor, Nike Hercules . Hercules was an existential threat to BOMARC, as its much greater range and nuclear warhead filled many of the roles that BOMARC was designed for. A new round of fighting in the press broke out, capped by an article in The New York Times entitled "Air Force Calls Army Nike Unfit To Guard Nation". In October 1957,
3560-556: The Bomarc missiles, which were housed in a constant combat-ready basis in individual launch shelters in remote areas. At the height of the program, there were 14 Bomarc sites located in the US and two in Canada. The liquid-fuel booster of the Bomarc A had several drawbacks. It took two minutes to fuel before launch, which could be a long time in high-speed intercepts, and its hypergolic propellants (hydrazine and nitric acid) were very dangerous to handle, leading to several serious accidents. As soon as high-thrust solid-fuel rockets became
3649-676: The Bomarc was within 10 mi (16 km) of the target, its own Westinghouse AN/DPN-34 radar guided the missile to the interception point. The maximum range of the IM-99A was 250 mi (400 km), and it was fitted with either a conventional high-explosive or a 10 kiloton W-40 nuclear fission warhead. The Bomarc relied on the Semi-Automatic Ground Environment (SAGE), an automated control system used by NORAD for detecting, tracking and intercepting enemy bomber aircraft . SAGE allowed for remote launching of
CIM-10 Bomarc - Misplaced Pages Continue
3738-490: The Diefenbaker Cabinet , and led to the collapse of the government in 1963. The Official Opposition and Liberal Party leader Lester B. Pearson originally was against nuclear missiles, but reversed his personal position and argued in favour of accepting nuclear warheads. He won the 1963 election , largely on the basis of this issue, and his new Liberal government proceeded to accept nuclear-armed Bomarcs, with
3827-584: The IM-99B. However, in March 1960, HQ USAF cut deployment to eight sites in the United States and two in Canada. Within a year of operations, a Bomarc A with a nuclear warhead caught fire at McGuire AFB on 7 June 1960 after its on-board helium tank exploded. While the missile's explosives did not detonate, the heat melted the warhead and released plutonium, which the fire crews spread. The Air Force and
3916-539: The Second World War. Company officials claimed, in December 1945, that these domestic initiatives were uninfluenced by parallel German developments. One post-war U.S. intelligence assessment described the Kawasaki ram jet's centrifugal fuel disperser as the company's "most outstanding accomplishment ... eliminat[ing] a large amount of the fuel injection system normally employed." Because of excessive vibration,
4005-567: The Soviet Union, a theory of supersonic ramjet engines was presented in 1928 by Boris Stechkin . Yuri Pobedonostsev, chief of GIRD 's 3rd Brigade, carried out research. The first engine, the GIRD-04, was designed by I.A. Merkulov and tested in April 1933. To simulate supersonic flight, it was fed by air compressed to 200 bar , and was fueled with hydrogen. The GIRD-08 phosphorus-fueled ramjet
4094-574: The States and Empires of the Moon ) (1657) was the first of three satirical novels written by Cyrano de Bergerac that are considered among the first science fiction stories. Arthur C Clarke credited this book with conceiving the ramjet, and as the first fictional example of rocket-powered space flight. The ramjet was designed in 1913 by French inventor René Lorin , who was granted a patent (FR290356) for his device. He could not test his invention due to
4183-514: The USAF 425th Munitions Maintenance Squadron at Stewart Air Force Base . During operational service, the Bomarcs were maintained on stand-by, on a 24-hour basis, but were never fired, although the squadron test-fired the missiles at Eglin AFB, Florida on annual winter retreats. No. 447 SAM Squadron operating out of RCAF Station La Macaza, Quebec , was activated on 15 September 1962 although warheads were not delivered until late 1963. The squadron followed
4272-507: The USAF discontinued the use of aircraft-like type designators for missiles, and the XF-99A and YF-99A became XIM-99A and YIM-99A, respectively. Originally the USAF had allocated the designation IM-69, but this was changed (possibly at Boeing's request to keep number 99) to IM-99 in October 1955. By this time, Ajax was widely deployed around the United States and some overseas locations, and
4361-408: The United States with 120 missiles each but as defense budgets decreased during the 1950s the number of sites dropped substantially. Ongoing development and reliability problems didn't help, nor did Congressional debate over the missile's usefulness and necessity. In June 1959, the Air Force authorized 16 Bomarc sites with 56 missiles each; the initial five would get the IM-99A with the remainder getting
4450-543: The XF-99 test vehicles began in September 1952 and continued through early 1955. The XF-99 tested only the liquid-fueled booster rocket, which would accelerate the missile to ramjet ignition speed. In February 1955, tests of the XF-99A propulsion test vehicles began. These included live ramjets, but still had no guidance system or warhead. The designation YF-99A had been reserved for the operational test vehicles. In August 1955,
4539-541: The accident, the McGuire complex has never been sold or converted to other uses and remains in Air Force ownership, making it the most intact site of the eight in the US. It has been nominated to the National Register of Historic Sites. Although a number of IM-99/CIM-10 Bomarcs have been placed on public display, because of concerns about the possible environmental hazards of the thoriated magnesium structure of
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#17327875537124628-619: The airframe several have been removed from public view. Russ Sneddon, director of the Air Force Armament Museum , Eglin Air Force Base, Florida provided information about missing CIM-10 exhibit airframe serial 59–2016, one of the museum's original artifacts from its founding in 1975 and donated by the 4751st Air Defense Squadron at Hurlburt Field , Eglin Auxiliary Field 9, Eglin AFB. As of December 2006,
4717-421: The booster is mounted immediately aft of the ramjet, e.g. Sea Dart , or wraparound where multiple boosters are attached around the outside of the ramjet, e.g. 2K11 Krug . The choice of booster arrangement is usually driven by the size of the launch platform. A tandem booster increases the length of the system, whereas wraparound boosters increase the diameter. Wraparound boosters typically generate higher drag than
4806-496: The booster's higher thrust levels, a differently shaped nozzle is required for optimum thrust compared to that required for the lower thrust ramjet sustainer. This is usually achieved via a separate nozzle, which is ejected after booster burnout. However, designs such as Meteor feature nozzleless boosters. This offers the advantages of elimination of the hazard to launch aircraft from the boost debris, simplicity, reliability, and reduced mass and cost, although this must be traded against
4895-457: The compressed air bottle from which it is inflated, which is mounted lengthwise in the tank. This offers a lower-cost approach than a regulated LFRJ requiring a pump system to supply the fuel. A ramjet generates no static thrust and needs a booster to achieve a forward velocity high enough for efficient operation of the intake system. The first ramjet-powered missiles used external boosters, usually solid-propellant rockets, either in tandem, where
4984-580: The contract for a long-range design known as Ground-to-Air Pilotless Aircraft , or GAPA. GAPA moved to the United States Air Force when that branch was formed in 1947. In 1946, the USAAF also started two early research projects into anti-missile systems in Project Thumper (MX-795) and Project Wizard (MX-794). Formally organized in 1946 under USAAF project MX-606, by 1950 Boeing had launched more than 100 test rockets in various configurations, all under
5073-504: The designator XSAM-A-1 GAPA. The tests were very promising, and Boeing received a USAF contract in 1949 to develop a production design under project MX-1599. The MX-1599 missile was to be a ramjet-powered, nuclear-armed long-range surface-to-air missile to defend the Continental United States from high-flying bombers. The Michigan Aerospace Research Center (MARC) was added to the project soon afterward, and this gave
5162-557: The end of 1958, ADC plans called for construction of the following BOMARC bases in the following order: l. McGuire 2. Suffolk 3. Otis 4. Dow 5. Langley 6. Truax 7. Kinross 8. Duluth 9. Ethan Allen 10. Niagara Falls 11. Paine 12. Adair 13. Travis 14. Vandenberg 15. San Diego 16. Malmstrom 17. Grand Forks 18. Minot 19. Youngstown 20. Seymour-Johnson 21. Bunker Hill 22. Sioux Falls 23. Charleston 24. McConnell 25. Holloman 26. McCoy 27. Amarillo 28. Barksdale 29. Williams . The first USAF operational Bomarc squadron
5251-635: The engine was only intended for use in rocket, or catapult-launched pilotless aircraft. Preparations for flight testing ended with the Japanese surrender in August 1945. In 1936, Hellmuth Walter constructed a test engine powered by natural gas . Theoretical work was carried out at BMW , Junkers , and DFL . In 1941, Eugen Sänger of DFL proposed a ramjet engine with a high combustion chamber temperature. He constructed large ramjet pipes with 500 millimetres (20 in) and 1,000 millimetres (39 in) diameter and carried out combustion tests on lorries and on
5340-464: The first YIM-99A production-representative prototype flew with full guidance, and succeeded to pass the target within destructive range. In late 1957, Boeing received the production contract for the IM-99A Bomarc A, and in September 1959, the first IM-99A squadron became operational. The IM-99A had an operational radius of 200 miles (320 km) and was designed to fly at Mach 2.5–2.8 at
5429-405: The first being deployed on 31 December 1963. When the nuclear warheads were deployed, Pearson's wife, Maryon, resigned her honorary membership in the anti-nuclear weapons group, Voice of Women. Canadian operational deployment of the Bomarc involved the formation of two specialized Surface/Air Missile squadrons. The first to begin operations was No. 446 SAM Squadron at RCAF Station North Bay , which
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#17327875537125518-427: The flame and improve fuel mixing. Over-fuelling the combustor can cause the final (normal) shock in the diffuser to be pushed forward beyond the intake lip, resulting in a substantial drop in airflow and thrust. The propelling nozzle is a critical part of a ramjet design, since it accelerates exhaust flow to produce thrust. Subsonic ramjets accelerate exhaust flow with a nozzle . Supersonic flight typically requires
5607-418: The fuel to the ramcombustor is required, which can be complicated and expensive. This propulsion system was first perfected by Yvonne Brill during her work at Marquardt Corporation . Aérospatiale-Celerg designed an LFRJ where the fuel is forced into the injectors by an elastomer bladder that inflates progressively along the length of the fuel tank. Initially, the bladder forms a close-fitting sheath around
5696-425: The incoming air is slowed to subsonic velocities for combustion. In addition, the combustion chamber's inlet temperature increases to very high values, approaching the dissociation limit at some limiting Mach number. Ramjet diffusers slow the incoming air to a subsonic velocity before it enters the combustor. Scramjets are similar to ramjets, but the air flows through the combustor at supersonic speed. This increases
5785-521: The launch of an unarmed missile at Eglin. In September 1959 the squadron assembled at their permanent station, the Bomarc site near McGuire AFB, and trained for operational readiness. The first Bomarc-A were used at McGuire on 19 September 1959 with Kincheloe AFB getting the first operational IM-99Bs. While several of the squadrons replicated earlier fighter interceptor unit numbers, they were all new organizations with no previous historical counterpart. ADC's initial plans called for some 52 Bomarc sites around
5874-572: The launch order, the shelter's roof would slide open, and the missile raised to the vertical. After the missile was supplied with fuel for the booster rocket, it would be launched by the Aerojet General LR59-AJ-13 booster. After sufficient speed was reached, the Marquardt RJ43-MA-3 ramjets would ignite and propel the missile to its cruise speed of Mach 2.8 at an altitude of 66,000 ft (20,000 m). When
5963-479: The name came from a comparison with the turbojet engine which employs relatively complex and expensive spinning turbomachinery. The US Navy developed a series of air-to-air missiles under the name of " Gorgon " using different propulsion mechanisms, including ramjet propulsion on the Gorgon IV. The ramjet Gorgon IVs, made by Glenn Martin , were tested in 1948 and 1949 at Naval Air Station Point Mugu . The ramjet
6052-485: The new missile its name Bomarc (for Boeing and MARC). In 1951, the USAF decided to emphasize its point of view that missiles were nothing else than pilotless aircraft by assigning aircraft designators to its missile projects, and anti-aircraft missiles received F-for-Fighter designations. The Bomarc became the F-99 . By this time, the Army's Nike project was progressing well and would enter operational service in 1953. This led
6141-565: The others remained on alert through 1972. In April 1972, the last Bomarc B in U.S. Air Force service was retired at McGuire and the 46th ADMS inactivated and the base was deactivated. In the era of the intercontinental ballistic missiles the Bomarc, designed to intercept relatively slow manned bombers, had become a useless asset. The remaining Bomarc missiles were used by all armed services as high-speed target drones for tests of other air-defense missiles. The Bomarc A and Bomarc B targets were designated as CQM-10A and CQM-10B, respectively. Following
6230-585: The pressure recovered from the streaming air and improves net thrust. Thermal choking of the exhaust is avoided by having a relatively high supersonic air velocity at combustor entry. Fuel injection is often into a sheltered region below a step in the combustor wall. The Boeing X-43 was a small experimental ramjet that achieved Mach 5 (1,700 m/s; 6,100 km/h) for 200 seconds on the X-51A Waverider . Michigan Aeronautical Research Center The Michigan Aeronautical Research Center (MARC)
6319-437: The reduction in performance of a dedicated booster nozzle. A slight variation on the ramjet uses the supersonic exhaust from a rocket combustion process to compress and react with the incoming air in the main combustion chamber. This has the advantage of giving thrust even at zero speed. In a solid fuel integrated rocket ramjet (SFIRR), the solid fuel is cast along the outer wall of the ramcombustor. In this case, fuel injection
6408-430: The relatively low pressure means the ramjets are outperformed by turbojets and rockets . Ramjets can be classified according to the type of fuel, either liquid or solid; and the booster. In a liquid fuel ramjet (LFRJ), hydrocarbon fuel (typically) is injected into the combustor ahead of a flameholder. The flameholder stabilises the flame with the compressed air from the intake(s). A means of pressurizing and supplying
6497-587: The remainder of the flight. This was the same model of engine used to power the Lockheed X-7 , the Lockheed AQM-60 Kingfisher drone used to test air defenses, and the Lockheed D-21 launched from the back of an M-21 , although the Bomarc and Kingfisher engines used different materials due to the longer duration of their flights. The operational IM-99A missiles were based horizontally in semi-hardened shelters, nicknamed "coffins". After
6586-539: The same engines as the AQM-60, but with improved materials to endure longer flight times. The system was withdrawn in the 1970s as the threat from bombers subsided. In April 2020, the U.S. Department of Defense and the Norwegian Ministry of Defense jointly announced their partnership to develop advanced technologies applicable to long range high-speed and hypersonic weapons. The Tactical High-speed Offensive Ramjet for Extended Range (THOR-ER) program completed
6675-567: The same operational procedures as No. 446, its sister squadron. With the passage of time the operational capability of the 1950s-era Bomarc system no longer met modern requirements; the Department of National Defence deemed that the Bomarc missile defense was no longer a viable system, and ordered both squadrons to be stood down in 1972. The bunkers and ancillary facilities remain at both former sites. Download coordinates as: Locations under construction but not activated. Each site
6764-423: The same time, and the two services fought constantly both in political circles and in the press. Development dragged on, and by the time it was ready for deployment in the late 1950s, the nuclear threat had moved from manned bombers to the intercontinental ballistic missile (ICBM). By this time the Army had successfully deployed the much shorter range Nike Hercules that they claimed filled any possible need through
6853-1081: The simplicity of the SFRJ and LFRJ's unlimited speed control. Ramjets generally give little or no thrust below about half the speed of sound , and they are inefficient ( specific impulse of less than 600 seconds) until the airspeed exceeds 1,000 kilometres per hour (280 m/s; 620 mph) due to low compression ratios. Even above the minimum speed, a wide flight envelope (range of flight conditions), such as low to high speeds and low to high altitudes, can force significant design compromises, and they tend to work best optimised for one designed speed and altitude (point designs). However, ramjets generally outperform gas turbine-based jet engine designs and work best at supersonic speeds (Mach 2–4). Although inefficient at slower speeds, they are more fuel-efficient than rockets over their entire useful working range up to at least Mach 6 (2,000 m/s; 7,400 km/h). The performance of conventional ramjets falls off above Mach 6 due to dissociation and pressure loss caused by shock as
6942-535: The suspect missile was stored in a secure compound behind the Armaments Museum. In December 2010, the airframe was still on premises, but partly dismantled. The Bomarc Missile Program was highly controversial in Canada. The Progressive Conservative government of Prime Minister John Diefenbaker initially agreed to deploy the missiles, and shortly thereafter controversially scrapped the Avro Arrow ,
7031-613: The system was cancelled. It was replaced by a shorter range ramjet missile system called the Bloodhound . The system was designed as a second line of defense in case attackers were able to bypass the fleet of defending English Electric Lightning fighters. In the 1960s the Royal Navy developed and deployed a ramjet powered surface to air missile for ships called the Sea Dart . It had a range of 65–130 kilometres (40–80 mi) and
7120-476: The target area it was commanded to begin a dive, activating an onboard active radar homing seeker for terminal guidance . A radar proximity fuse detonated the warhead, either a large conventional explosive or the W40 nuclear warhead . The Air Force originally planned for a total of 52 sites covering most of the major cities and industrial regions in the US. The United States Army was deploying their own systems at
7209-428: The unavailability of adequate equipment since there was no way at the time for an aircraft to go fast enough for a ramjet to function properly. His patent showed a piston internal combustion engine with added 'trumpets' as exhaust nozzles, expressing the idea that the exhaust from internal combustion engines could be directed into nozzles to create jet propulsion. The works of René Leduc were notable. Leduc's Model,
7298-550: Was designed at the University of Southern California and manufactured by the Marquardt Aircraft Company . The engine was 2.1 metres (7 ft) long and 510 millimetres (20 in) in diameter and was positioned below the missile. In the early 1950s the US developed a Mach 4+ ramjet under the Lockheed X-7 program. This was developed into the Lockheed AQM-60 Kingfisher . Further development resulted in
7387-627: Was intercepted. Because the new booster required less space in the missile, more ramjet fuel could be carried, thus increasing the range to 430 mi (700 km). The terminal homing system was also improved, using the world's first pulse Doppler search radar , the Westinghouse AN/DPN-53. All Bomarc Bs were equipped with the W-40 nuclear warhead. In June 1961, the first IM-99B squadron became operational, and Bomarc B quickly replaced most Bomarc A missiles. On 23 March 1961,
7476-548: Was one of America 's leading air research organizations, run by the University of Michigan at Willow Run Airport . It played a leading role in the creation of the Bomarc Missile Program , alongside Boeing . Willow Run Laboratories was created in 1946, and in 1950, in recognition of an expanded research program, its name was changed to Willow Run Research Center , which would eventually be spun off from
7565-489: Was programmed for 28 IM-99B missiles: Reference for BOMARC units and locations: Below is a list of museums or sites which have a Bomarc missile on display: The Bomarc missile captured the imagination of the American and Canadian popular music industry, giving rise to a pop music group, the Bomarcs (composed mainly of servicemen stationed on a Florida radar site that tracked Bomarcs), a record label, Bomarc Records, and
7654-520: Was tested by firing it from an artillery cannon. These shells may have been the first jet-powered projectiles to break the speed of sound . In 1939, Merkulov did further ramjet tests using a two-stage rocket , the R-3. He developed the first ramjet engine for use as an auxiliary motor of an aircraft, the DM-1. The world's first ramjet-powered airplane flight took place in December 1940, using two DM-2 engines on
7743-523: Was the 46th Air Defense Missile Squadron (ADMS), organized on 1 January 1959 and activated on 25 March. The 46th ADMS was assigned to the New York Air Defense Sector at McGuire Air Force Base , New Jersey. The training program, under the 4751st Air Defense Wing used technicians acting as instructors and was established for a four-month duration. Training included missile maintenance; SAGE operations and launch procedures, including
7832-407: Was the command and control center for both squadrons. With construction of the compound and related facilities completed in 1961, the squadron received its Bomarcs in 1961, without nuclear warheads. The squadron became fully operational from 31 December 1963, when the nuclear warheads arrived, until disbanding on 31 March 1972. All the warheads were stored separately and under control of Detachment 1 of
7921-619: Was then known as Envirocare , located in Utah. In 1962, the US Air Force started using modified A-models as drones; following the October 1962 tri-service redesignation of aircraft and weapons systems they became CQM-10As. Otherwise the air defense missile squadrons maintained alert while making regular trips to Santa Rosa Island for training and firing practice. After the inactivation of the 4751st ADW(M) on 1 July 1962 and transfer of Hurlburt to Tactical Air Command for air commando operations
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