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141-408: The original SDB is equipped with a GPS-aided inertial navigation system to attack fixed/stationary targets such as fuel depots , bunkers , etc. The second variant, Raytheon's GBU-53/B SDB II , will include a thermal seeker and radar with automatic target recognition features for striking mobile targets such as tanks , vehicles , and mobile command posts. The small size of the bomb allows

282-687: A Lockheed F-117 Nighthawk . In order to strike from increased distances, the F-15E was equipped with the AGM-130, which provided a stand-off strike capability. Weeks after the September 11 attacks in 2001, the 391st Fighter Squadron deployed to Ahmad al-Jaber air base , Kuwait, to support Operation Enduring Freedom during the War in Afghanistan . F-15Es met little resistance during initial missions. On

423-448: A laser gyroscope to continuously monitor the aircraft's position and provide information to the central computer and other systems, including a digital moving map in both cockpits. The LANTIRN system is mounted externally under the engine intakes; it allows the aircraft to fly at low altitudes, at night, and in any weather conditions, to attack ground targets with a variety of precision-guided and unguided weapons. The LANTIRN system gives

564-408: A moving map display , or recorded or used by some other system, such as a vehicle guidance system. Although usually not formed explicitly in the receiver processing, the conceptual time differences of arrival (TDOAs) define the measurement geometry. Each TDOA corresponds to a hyperboloid of revolution (see Multilateration ). The line connecting the two satellites involved (and its extensions) forms

705-607: A $ 450 million contract for engineering and development. Although unit costs were somewhat uncertain as of 2006, the estimated cost for the INS/GPS version was around US$ 70,000. Boeing and the Italian firm Oto Melara signed a contract covering the license production of 500 GBU-39/B (INS/GPS) and 50 BRU-61/A racks for the Aeronautica Militare , at a cost of nearly US$ 34 million. The GBU-39/B began separation tests on

846-458: A 36-year-old Tunisian jihadist linked to the 2015 Sousse attacks . Sources said that 49 people were killed and 6 wounded; two Serbians kidnapped by IS in 2015 were also reportedly killed. On 8 June 2017, an F-15E shot down a pro-Syrian Regime UAV near Al Tanf, Syria ; according to OIR officials, it was downed after deploying "one of several weapons it was carrying near a position occupied by Coalition personnel... [It was] similar in size to

987-626: A 500 lb (230 kg) laser-guided bomb, killing three and wounding five others. On 7 April 2003, an F-15E, crewed by Captain Eric Das and Major William Watkins, performed a key interdiction mission in support of special forces, but crashed near Tikrit , Iraq. Das and Watkins were posthumously awarded the Distinguished Flying Cross and the Purple Heart . During the war, F-15Es were credited with destroying 60% of

1128-770: A GBU-39/B SDB in a strike at the gate of the Al-Mutanabbi school complex near Khan Younis in Southern Gaza, which was being used to house displaced people. The IDF stated that the strike was targeted against a Hamas operative, while the Palestinian Ministry of Health reported at least 27 killed and 53 injured in the strike. In August 2024, CNN reported that Israel used the GBU/39 again in the Al-Tabaeen school attack , killing over 90 people according to

1269-711: A U.S. MQ-1 Predator ". The drone may have been a Shahed 129 ; on 20 June 2017, a second Shahed-129 was downed by an F-15E near the 50 mile exclusion zone around Al-Tanf. On 21 August 2021, a USAF F-15E shot down an unidentified drone with an AIM-9X Sidewinder missile as the drone approached US forces in Eastern Syria. USAF F-15Es were deployed on 2 February 2024, during the airstrikes against Iranian backed militias in Iraq and Syria . USAF F-15Es helped blunt an Iranian attack against Israel on 13 April 2024 by shooting down over 70 Iranian one-way attack UAVs. The F-15I

1410-508: A close collaboration on the development of the F-15E's air-to-ground capabilities. To assist in the F-15E's development, McDonnell Douglas modified the second TF-15A prototype, AF serial number 71-0291 , as a demonstrator. The aircraft, known as the Advanced Fighter Capability Demonstrator, first flew on 8 July 1980. It was previously used to test conformal fuel tanks (CFTs), initially designed for

1551-552: A contract awarded in September 2006, Boeing developed a version of the SDB I that replaces the steel casing with a lightweight composite casing and the warhead with a focused-blast explosive such as dense inert metal explosive (DIME). This should further reduce collateral damage when using the weapon for pinpoint strikes in urban areas. The USAF intends to use the same FLM casing on a weapon of 500 pounds (227 kg). Boeing celebrated

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1692-479: A correlation station at the theatre Air Operations Center . The corrections are then transmitted by Link 16 to SDB-equipped aircraft. In November 2014, the U.S. Air Force began the development of a version of the SDB I intended to track and attack sources of electronic warfare jamming directed to disrupt the munitions' guidance. The home-on-GPS jam (HOG-J) seeker works similar to the AGM-88 HARM to follow

1833-705: A deliberate error introduced into the GPS data that military receivers could correct for. As civilian GPS usage grew, there was increasing pressure to remove this error. The SA system was temporarily disabled during the Gulf War , as a shortage of military GPS units meant that many US soldiers were using civilian GPS units sent from home. In the 1990s, Differential GPS systems from the US Coast Guard , Federal Aviation Administration , and similar agencies in other countries began to broadcast local GPS corrections, reducing

1974-450: A directive making GPS freely available for civilian use, once it was sufficiently developed, as a common good. The first Block II satellite was launched on February 14, 1989, and the 24th satellite was launched in 1994. The GPS program cost at this point, not including the cost of the user equipment but including the costs of the satellite launches, has been estimated at US$ 5 billion (equivalent to $ 10 billion in 2023). Initially,

2115-501: A fraction of the cost; "As we think about the fiscal constraints that we’re under and DoD is under, it’s the right kind of answer where you get an 80 percent solution at a fraction of the cost.” In June 2013, Boeing secured a contract for the development and testing of the LSDB. Under the contract Boeing was to provide engineering, integration test, and production support, plus the development of an LSDB Weapon Simulator. According to Boeing,

2256-517: A full complement of 24 satellites in 2027. The GPS project was launched in the United States in 1973 to overcome the limitations of previous navigation systems, combining ideas from several predecessors, including classified engineering design studies from the 1960s. The U.S. Department of Defense developed the system, which originally used 24 satellites, for use by the United States military, and became fully operational in 1993. Civilian use

2397-596: A house where Saddam Hussein was believed to be; F-15Es dropped GBU-28s around the H3 airfield. On 20 March, the effective start of the war, F-15Es fired AGM-130s against communication, command and control buildings, and other key targets in Baghdad; some weapons missed their intended targets, possibly due to jamming by EA-6B Prowlers in the vicinity. On 3 April 2003, an F-15E mistook a USA M270 Multiple Launch Rocket System (MLRS) for an Iraqi surface-to-air missile site and dropped

2538-592: A later time. Another choice is the F-35 Lightning II , set to replace other aircraft such as the F-16 Falcon ; a F-35E variant was studied. Adding a second seat to the F-35 is complex and costly, especially to preserve its stealth profile; providing for greater range and payload would also be difficult tasks. Alternatively, the role could be covered by a combination of fighter and bomber aircraft, such as

2679-429: A liaison. The U.S. Department of Defense is required by law to "maintain a Standard Positioning Service (as defined in the federal radio navigation plan and the standard positioning service signal specification) that will be available on a continuous, worldwide basis" and "develop measures to prevent hostile use of GPS and its augmentations without unduly disrupting or degrading civilian uses". USA-203 from Block IIR-M

2820-413: A low-threat environment for air operations. Aircraft commonly flew on-call support missions for allied ground forces, F-15Es usually carried MK-82 and GBU-12 bombs in this role, other weapons were sometimes carried, during one mission a GBU-28, two GBU-24s and six GBU-12s were released. Frequent targets during the rest of the war were individual insurgents, light vehicles and supply convoys; cannon fire

2961-563: A manageable level to permit accurate navigation. During Labor Day weekend in 1973, a meeting of about twelve military officers at the Pentagon discussed the creation of a Defense Navigation Satellite System (DNSS) . It was at this meeting that the real synthesis that became GPS was created. Later that year, the DNSS program was named Navstar. Navstar is often erroneously considered an acronym for "NAVigation System using Timing And Ranging" but

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3102-816: A menu of display options. Unlike previous two-place jets (e.g. the F-14 Tomcat and Navy variants of the F-4), whose back seat omitted flying controls , the F-15E's back seat is equipped with its own stick and throttle so the WSO can take over flying, albeit with reduced visibility. For extended range, the F-15E is fitted with two conformal fuel tanks (CFTs) that hug the fuselage to produce lower drag than conventional underwing/underbelly drop tanks . They carry 750 U.S. gallons (2,800 L) of fuel, and house six weapons hardpoints in two rows of three in tandem. Unlike conventional drop tanks, CFTs cannot be jettisoned, thus increased range

3243-461: A minimum, four satellites must be in view of the receiver for it to compute four unknown quantities (three position coordinates and the deviation of its own clock from satellite time). Each GPS satellite continually broadcasts a signal ( carrier wave with modulation ) that includes: Conceptually, the receiver measures the TOAs (according to its own clock) of four satellite signals. From the TOAs and

3384-679: A payload capability up to 100 lb (45 kg). An ALASA vehicle is to be fitted under an F-15E, which will climb to 40,000 ft, then be released and fire its four engines to reach low-Earth orbit. Awarding the contract to Boeing would make use of the F-15E as the carriage vehicle, as previous design contracts had been given to Lockheed Martin to use the F-22 Raptor and Virgin Galactic to use their SpaceShip Two aircraft. DARPA had previously insisted they wanted to select an aircraft they would not need to modify heavily to carry and launch

3525-431: A receiver start-up situation. Most receivers have a track algorithm , sometimes called a tracker , that combines sets of satellite measurements collected at different times—in effect, taking advantage of the fact that successive receiver positions are usually close to each other. After a set of measurements are processed, the tracker predicts the receiver location corresponding to the next set of satellite measurements. When

3666-490: A repetition. F-15Es of the 391st Fighter Squadron , 492d Fighter Squadron , and 494th Fighter Squadron regularly deployed to Turkey throughout the 1990s. In January 1993, in breach of the ceasefire agreement, Iraqi targets below the 32nd parallel north were attacked; 10 F-15Es conducted a punitive strike days later . Most missions were of a defensive nature, the Strike Eagles carried a flexible range of weapons on

3807-466: A second and final F-15E was downed by an Iraqi SA-2 ; the crew survived and evaded capture for several days and made contact with coalition aircraft, but a rescue was not launched due to security issues over an airman who failed to identify himself with proper codes. The Iraqis later captured both airmen. F-15Es destroyed 18 Iraqi jets on the ground at Tallil air base using GBU-12s and CBU-87s . On 14 February, an F-15E scored its only air-to-air kill of

3948-455: A second strike of 21 F-15Es. At night-time, F-15Es flew hunter missions over western Iraq, searching for mobile SCUD launchers. By conducting random bombings in suspected areas, it was hoped to deter the Iraqis from setting up for a Scud launch. On the war's opening night, an F-15E failed to hit a MiG-29 with an AIM-9 Sidewinder; other F-15Es also unsuccessfully engaged this lone MiG-29, which

4089-427: A single-strike aircraft to carry more of them than previously available bombs, and thus strike more targets. The SDB carries approximately 36 lb (16 kg) of AFX-757 high explosive . It has integrated "DiamondBack" type wings which deploy after release, increasing the glide time and therefore the maximum range. Its size and accuracy allow for an effective munition with less collateral damage . Warhead penetration

4230-573: A tracking system that mark an enemy for destruction as far away as 10 mi (16 km). Once tracking has started, targeting information is automatically handed off to infrared homing air-to-surface missiles or laser-guided bombs . The targeting pod is mounted beneath the left engine intake; configurations may be either the AN/AAQ-14 , AN/AAQ-28(V) Litening , or the AN/AAQ-33 Sniper . The F-15E carries most air-to-ground weapons in

4371-490: A typical mission. AWACS aircraft were in close contact with F-15E crews, who would receive new taskings while airborne and thus could fly unplanned attacks on Iraqi targets. After 1993, no-fly zone violations were minimal as Iraq staged a minor withdrawal; in 1997, Turkey approved the creation of Operation Northern Watch (ONW) and permitted US forces to use the Incirlik air base. In December 1998, Operation Desert Fox

GBU-39 Small Diameter Bomb - Misplaced Pages Continue

4512-661: A version of the F-16 Fighting Falcon , while McDonnell Douglas offered both the F/A-18 Hornet and the F-15E. On 27 January 1994, the Israeli government announced their intention to buy 21 modified F-15Es, designated F-15I . On 12 May 1994, the US Government authorized the purchase of up to 25 F-15Is by Israel. In November 1995, Israel ordered four extra F-15Is; 25 were built from 1996 to 1998. Some of

4653-457: A very low altitude following cues displayed on a HUD; it also can be coupled to the autopilot to provide "hands off" terrain-following capability. This pod also contains a forward-looking infrared system which is projected on the HUD, typically used during nighttime or low-visibility operations. The nav pod is installed beneath the right engine intake. The targeting pod contains a laser designator and

4794-550: Is 3 ft (1 m) of steel reinforced concrete under 3 ft (1 m) of earth and the fuze has electronic safe and fire (ESAF) cockpit selectable functions, including air burst and delayed options. The SDB I has a circular error probable (CEP) precision of 3 ft (1 m). CEP is reduced by updating differential GPS offsets prior to weapon release. These offsets are calculated using an SDB Accuracy Support Infrastructure, consisting of three or more GPS receivers at fixed locations transmitting calculated location to

4935-456: Is a trade-off for increased drag and weight compared to a "clean" configuration. The tactical electronic warfare system (TEWS) integrates all countermeasures on the craft: radar warning receivers, radar jammer, radar and chaff / flare dispensers are all tied to the TEWS to provide comprehensive defense against detection and tracking. This system includes an externally mounted ALQ-131 ECM pod which

5076-622: Is carried on the centerline pylon when required. The MIDS Fighter Data Link Terminal, produced by BAE Systems , improves situational awareness and communications capabilities via the Link 16 datalink. The TEWS was replaced by the AN/ALQ-250 EPAWSS digital electronic warfare suite beginning in 2022; EPAWSS replaces all TEWS components with lighter and more capable digital ones for increased performance. The APG-70 radar allows crews to detect ground targets from longer ranges; one feature

5217-464: Is equipped for a weapon systems officer (WSO, pronounced "wizzo") to work the air-to-ground avionics via multiple screens; these view the radar , electronic warfare , or thermographic cameras , monitor aircraft or weapons status and possible threats, select targets, and use an electronic moving map to navigate. Two hand controls are used to select new displays and to refine targeting information; displays can be moved from one screen to another using

5358-641: Is involved in the design and manufacture of the Conformal Weapons Bay (CWB) for the F-15 Silent Eagle . The engines used on early aircraft are Pratt & Whitney F100 -PW-220. Later batches feature the more powerful P&W F100-PW-229 engines. Saudi Arabian and Israeli aircraft originally used P&W F100-229 engines. In 2008, Saudi Arabia decided to re-engine their F-15S and F-15SA fleets with General Electric F110 -GE-129 engines. The South Korean F-15K had two different engines;

5499-462: Is one of the global navigation satellite systems (GNSS) that provide geolocation and time information to a GPS receiver anywhere on or near the Earth where there is an unobstructed line of sight to four or more GPS satellites. It does not require the user to transmit any data, and operates independently of any telephone or Internet reception, though these technologies can enhance the usefulness of

5640-598: Is operated by the Israeli Defense Force / Air Force No 69 Squadron , succeeding the F-4 Phantom II. It is used akin to a strategic bomber due to its long range, high munition capacity and advanced systems. After the Gulf War in 1991, in which Israeli towns were attacked by SCUD missiles based in Iraq, the Israeli government decided a long range strike aircraft was needed, issuing a Request for Information (RFI). In response, Lockheed Martin offered

5781-527: Is owned and operated by the United States government as a national resource. The Department of Defense is the steward of GPS. The Interagency GPS Executive Board (IGEB) oversaw GPS policy matters from 1996 to 2004. After that, the National Space-Based Positioning, Navigation and Timing Executive Committee was established by presidential directive in 2004 to advise and coordinate federal departments and agencies on matters concerning

GBU-39 Small Diameter Bomb - Misplaced Pages Continue

5922-615: Is that, after a sweep of a target area, the crew may freeze the air-to-ground map then switch to air-to-air mode to scan for aerial threats. During air-to-surface weapon delivery, the pilot is capable of detecting, targeting, and engaging air-to-air targets while the WSO designates ground targets. The APG-70 was replaced by the AN/APG-82(V)1 AESA radar, which began flight tests in January 2010 and achieved initial operational capability in 2014. Its inertial navigation system uses

6063-808: Is unhealthy For a more complete list, see List of GPS satellites On February 10, 1993, the National Aeronautic Association selected the GPS Team as winners of the 1992 Robert J. Collier Trophy , the US's most prestigious aviation award. This team combines researchers from the Naval Research Laboratory, the U.S. Air Force, the Aerospace Corporation , Rockwell International Corporation, and IBM Federal Systems Company. The citation honors them "for

6204-624: The B-21 Raider . The F-15E may also be replaced by a clean-sheet sixth-generation aircraft design. On 24 March 2014, Boeing won a $ 30.6 million contract from DARPA as part of the Airborne Launch Assist Space Access (ALASA) program. The goal of the program is to cut the cost of putting microsatellites into orbit by 66% through advances in launch systems. Under the 11-month contract, Boeing will build twelve 24 ft (7.3 m) launch vehicles, each with

6345-503: The Doppler effect , they could pinpoint where the satellite was along its orbit. The Director of the APL gave them access to their UNIVAC I computer to perform the heavy calculations required. Early the next year, Frank McClure, the deputy director of the APL, asked Guier and Weiffenbach to investigate the inverse problem: pinpointing the user's location, given the satellite's. (At the time,

6486-676: The F-15 Advanced Eagle family that began with the F-15SA (Saudi Advanced) for the Royal Saudi Air Force , which first flew in 2013. It replaces the older hybrid electronic/mechanical system with a digital fly-by-wire control system that opens up two additional wing pylons and a revised wing structure for increased service life. The Advanced Eagle would have further developed variants with the F-15QA (Qatari Advanced) for

6627-587: The F-22 Raptor in early September 2007, after more than a year of sometimes difficult work to integrate the weapon in the weapons bay and carry out airborne captive carry tests. The SDB is integrated on the F-15E Strike Eagle , Panavia Tornado , JAS-39 Gripen , F-16 Fighting Falcon , F-22 Raptor and AC-130W . Future integration is planned for the F-35 Lightning II , A-10 Thunderbolt II , B-1 Lancer , B-2 Spirit , B-52 Stratofortress and AC-130J . Other aircraft, including UCAVs , may also receive

6768-808: The F/A-18E/F Super Hornet with the antenna of the APG-63(V)3 AESA being fitted on the F-15C; it was named APG-63(V)4 until it received the APG-82 designation in 2009. The new radar is to be part of the F-15E Radar Modernization Program, which also includes a wideband radome (enabling operation on more radar frequencies) and environment control and electronic warfare improvements. In 2015, Boeing and BAE Systems were awarded contracts to comprehensively upgrade of

6909-543: The GLSDB ground-launched version of the Small Diameter Bomb, which was regarded "ineffective" due to Russian jamming. They are also harder to intercept due to their small size. This small size, combined with being air-launched, means that the SDB might hit a target before Russian electronic warfare can jam the weapon. The GLSDB has a "parabolic flight path" of artillery fire that can be detected on radar. Under

7050-628: The Iraqi Republican Guard / Baath Party HQ in Basrah while another flight of four destroyed a nearby Air Defense Sector HQ with six GBU-10s. In late February, the 336th received additional aircrews, many drafted from the two non-deployable squadrons at Seymour Johnson (the 333d and 334th Fighter Squadrons ) and 391st Fighter Squadron at Mountain Home Air Force Base , for a total of four aircrews per F-15E. In March,

7191-705: The Libyan no-fly zone as part of Operation Odyssey Dawn . On 21 March 2011, an F-15E from the 492d Fighter Squadron crashed near Bengazi, Libya. Both crew members parachuted into territory held by resistance elements of the Libyan population and were eventually rescued by US Marines. Equipment problems caused a weight imbalance and contributed to the crash when leaving the target area. USAF F-15Es have participated in Operation Inherent Resolve against Islamic State (IS) militants in Iraq and Syria. On

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7332-908: The Persian Gulf . During January 2003, the 336th was deployed to Al Udeid Air Base , Qatar, in coordination with planners of the Combined Air Operations Center at Prince Sultan Air Base, Saudi Arabia. In late January, F-15Es began flying in Operation Southern Watch, typically performing surveillance and reconnaissance missions. Additional roles included simulated combat against potential Iraqi targets and regional familiarization with local procedures and rules of engagement . During OSW, F-15Es struck targets in southern and western Iraq, including radars, radio stations, command and control sites, and air defences. On one night, four F-15Es released multiple GBU-24s on

7473-644: The Qatari Emiri Air Force and the F-15EX Eagle II for the USAF. In FY 2020, USAF began procuring the F-15EX to replace the aging fleet of F-15C/D and supplement the F-22 Raptor to maintain air superiority fighter numbers, taking advantage of the existing export production line to quickly and affordably bring additional fighters into service; the F-15EX is also an option to replace the F-15E at

7614-504: The navigation equations gives the position of the receiver along with the difference between the time kept by the receiver's on-board clock and the true time-of-day, thereby eliminating the need for a more precise and possibly impractical receiver based clock. Applications for GPS such as time transfer , traffic signal timing, and synchronization of cell phone base stations , make use of this cheap and highly accurate timing. Some GPS applications use this time for display, or, other than for

7755-543: The 335th Fighter Squadron's personnel and aircraft joined the 336th at Al Udeid. One objective was the destruction of Iraq's air defenses and Early Warning radar network near the Jordanian border, allowing F-16s and helicopters to operate from Jordan from the war's outset. Several radar sites and radio relay stations were hit in western Iraq near the "H3" airfield, encountering heavy anti-aircraft fire. On 19 March, as F-117 Nighthawks dropped bombs over Baghdad , targeting

7896-510: The ALASA payload. The project was terminated in late 2015. The F-15E's deep-strike mission is a radical departure from the original intent of the F-15 since it was designed as an air-superiority fighter under the mantra "not a pound for air-to-ground." The basic airframe, however, proved versatile enough to produce a very capable strike fighter. The F-15E, while designed for ground attack, retains

8037-577: The Alternative Warhead (AW), designed for the M270 's GMLRS to achieve area effects without leaving behind unexploded ordnance , had been successfully tested on the SDB. In 2002, while Boeing and Lockheed Martin were competing to develop the Small Diameter Bomb, Darleen A. Druyun – at that time Principal Deputy Assistant Secretary of the Air Force for Acquisition and Management – deleted

8178-576: The Bosnian capital, Sarajevo . On 9 September, an F-15E deployed the type's first GBU-15 bomb; dropping nine on Bosnian-Serb ground forces and air defense targets near Banja Luka . In response to the displacement of Kosovars and the Serbian government's rejection of a NATO ultimatum, Operation Allied Force was launched in March 1999. A total of 26 F-15Es flew the first strikes of Allied Force against Serb surface-to-air-missile sites, anti-aircraft batteries and early warning radar stations. Strike Eagles were deployed to Aviano as well as RAF Lakenheath in

8319-473: The Earth's center) and the offset of the receiver clock relative to the GPS time are computed simultaneously, using the navigation equations to process the TOFs. The receiver's Earth-centered solution location is usually converted to latitude , longitude and height relative to an ellipsoidal Earth model. The height may then be further converted to height relative to the geoid , which is essentially mean sea level. These coordinates may be displayed, such as on

8460-409: The F-15 under the designation "FAST Pack", with FAST standing for "Fuel and Sensor, Tactical. It was subsequently fitted with a Pave Tack laser designator targeting pod to allow the independent delivery of guided bombs . The demonstrator was displayed at the 1980 Farnborough Airshow . In March 1981, the USAF announced the Enhanced Tactical Fighter program to replace the F-111. The program

8601-466: The F-15's Head-up display; a total number of 150 HUDs were delivered by 2011. LIG Nex1 had been a participant in the F-15K program as a subcontractor to Rockwell Collins . LIG Nex1 is also preparing to manufacture F-15's new multi-function display and flight control computer. Also since 2004, Korea Aerospace Industries (KAI) has produced the F-15's wings and forward fuselages; in 2008, KAI established another production line for Singapore's F-15SG. KAI

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8742-417: The F-15E design through the Advanced Eagle family, including the F-15EX Eagle II . The McDonnell Douglas F-15 Eagle was introduced by the USAF to replace its fleet of McDonnell Douglas F-4 Phantom IIs . Unlike the F-4, the F-15 was designed for air superiority with little consideration for a ground-attack role; the F-15 Special Project Office opposed the idea of F-15s performing interdiction, giving rise to

8883-400: The F-15E exceptional accuracy in weapons delivery day or night and in poor weather, and consists of two pods attached to the exterior of the aircraft. At night, the video picture from the LANTIRN can be projected on the head-up display (HUD), producing an infrared image of the ground. The AN/AAQ-13 navigation pod contains a terrain-following radar which allows the pilot to safely fly at

9024-450: The F-15E's lower development costs compared to the F-16XL (US$ 270 million versus US$ 470 million), a belief that the F-15E had future growth potential, and possessing twin-engine redundancy. The USAF was initially expected to procure 400 aircraft, a figure later revised to 392. Construction of the first three F-15Es started in July 1985. The first of these, 86-0183 , made its maiden flight on 11 December 1986. Piloted by Gary Jennings,

9165-426: The GPS and related systems. The executive committee is chaired jointly by the Deputy Secretaries of Defense and Transportation. Its membership includes equivalent-level officials from the Departments of State, Commerce, and Homeland Security, the Joint Chiefs of Staff and NASA . Components of the executive office of the president participate as observers to the executive committee, and the FCC chairman participates as

9306-411: The GPS positioning information. It provides critical positioning capabilities to military, civil, and commercial users around the world. Although the United States government created, controls, and maintains the GPS system, it is freely accessible to anyone with a GPS receiver. The GPS project was started by the U.S. Department of Defense in 1973. The first prototype spacecraft was launched in 1978 and

9447-668: The GPS service, including new signals for civil use and increased accuracy and integrity for all users, all the while maintaining compatibility with existing GPS equipment. Modernization of the satellite system has been an ongoing initiative by the U.S. Department of Defense through a series of satellite acquisitions to meet the growing needs of the military, civilians, and the commercial market. As of early 2015, high-quality Standard Positioning Service (SPS) GPS receivers provided horizontal accuracy of better than 3.5 meters (11 ft), although many factors such as receiver and antenna quality and atmospheric issues can affect this accuracy. GPS

9588-416: The Gaza Civil Defense. The IDF stated that it was a precision strike against a Hamas command and control center that killed at least 19 Hamas and Islamic Jihad terrorists. Global Positioning System The Global Positioning System ( GPS ), originally Navstar GPS , is a satellite-based radio navigation system owned by the United States Space Force and operated by Mission Delta 31 . It

9729-527: The Global Positioning System (GPS) its 60th Anniversary Award, nominated by IAF member, the American Institute for Aeronautics and Astronautics (AIAA). The IAF Honors and Awards Committee recognized the uniqueness of the GPS program and the exemplary role it has played in building international collaboration for the benefit of humanity. On December 6, 2018, Gladys West was inducted into the Air Force Space and Missile Pioneers Hall of Fame in recognition of her work on an extremely accurate geodetic Earth model, which

9870-463: The Hind was roughly 800 feet (240 m) over the ground when the 2,000 lb (910 kg) bomb hit its target. As another Coalition bombing operation had commenced, the F-15Es disengaged from combat with the remaining helicopters. F-15Es struck heavily defended targets throughout Iraq, prioritizing SCUD missile sites. Missions aimed at killing Iraqi President Saddam Hussein were undertaken by F-15Es, bombing several suspected locations. Prior to

10011-479: The Iraqi Medina Republican Guard's total force; they also struck 65 MiGs on the ground, and destroyed key air defense and command buildings in Baghdad. F-15Es worked with other jets deployed to Al Udeid, including RAAF F/A-18s , USAF F-16s and F-117s, RAF Panavia Tornados and US Navy F-14s. Following the adoption of United Nations Security Council Resolution 1973 on 17 March 2011, 18 USAF F-15Es were amongst other NATO and allied aircraft were deployed to enforce

10152-550: The LSDB can be constructed at a more economical cost compared to the planned Raytheon GBU-53/B SDB II, leveraging the same semi-active laser sensor as the JDAM to effectively target moving and maritime targets. However, Boeing admitted to a capability gap in the ability to engage targets in zero-visibility weather, lacking the millimeter wave radar of the GBU-53/B SDB II. In 2014, U.S. Special Operations Command began fielding

10293-460: The Laser SDB. It was reported that Israel used a GBU-39/B SDB during the strike that killed 45 civilians in a Rafah refugee tent camp on May 26, 2024. Its usage in a densely-populated civilian area was criticized by munitions experts. The size of the debris field indicated that the bombs may have been timed to detonate in air to maximize the area of damage. According to CNN, Israel also used

10434-480: The Navy TRANSIT system were too slow for the high speeds of Air Force operation. The Naval Research Laboratory (NRL) continued making advances with their Timation (Time Navigation) satellites, first launched in 1967, second launched in 1969, with the third in 1974 carrying the first atomic clock into orbit and the fourth launched in 1977. Another important predecessor to GPS came from a different branch of

10575-582: The Navy was developing the submarine-launched Polaris missile, which required them to know the submarine's location.) This led them and APL to develop the TRANSIT system. In 1959, ARPA (renamed DARPA in 1972) also played a role in TRANSIT. TRANSIT was first successfully tested in 1960. It used a constellation of five satellites and could provide a navigational fix approximately once per hour. In 1967,

10716-547: The SLBM situation. In 1960, the Air Force proposed a radio-navigation system called MOSAIC (MObile System for Accurate ICBM Control) that was essentially a 3-D LORAN System. A follow-on study, Project 57, was performed in 1963 and it was "in this study that the GPS concept was born". That same year, the concept was pursued as Project 621B, which had "many of the attributes that you now see in GPS" and promised increased accuracy for U.S. Air Force bombers as well as ICBMs. Updates from

10857-524: The TOTs, the receiver forms four time of flight (TOF) values, which are (given the speed of light) approximately equivalent to receiver-satellite ranges plus time difference between the receiver and GPS satellites multiplied by speed of light, which are called pseudo-ranges. The receiver then computes its three-dimensional position and clock deviation from the four TOFs. In practice the receiver position (in three dimensional Cartesian coordinates with origin at

10998-607: The U.S. Navy developed the Timation satellite, which proved the feasibility of placing accurate clocks in space, a technology required for GPS. In the 1970s, the ground-based OMEGA navigation system, based on phase comparison of signal transmission from pairs of stations, became the first worldwide radio navigation system. Limitations of these systems drove the need for a more universal navigation solution with greater accuracy. Although there were wide needs for accurate navigation in military and civilian sectors, almost none of those

11139-442: The U.S. Secretary of Defense, William Perry , in view of the widespread growth of differential GPS services by private industry to improve civilian accuracy. Moreover, the U.S. military was developing technologies to deny GPS service to potential adversaries on a regional basis. Selective Availability was removed from the GPS architecture beginning with GPS-III. Since its deployment, the U.S. has implemented several improvements to

11280-531: The U.S. Senate recommended zeroing out funding for the GBU-53/B SDB II due to fielding delays with the F-35 Lightning II. Commenting on the delay of the SDB II, Debbie Rub, Boeing 's VP & GM of Missiles and Unmanned Airborne Systems said, “Until that [SDB II] comes online … this is a nice gap filler to take care of an important warfighting need," stating that Boeing could fill the gap in capability at

11421-515: The UK. In-theater, F-15Es conducted close air support (CAS) missions, a popular concept within the USAF. Missions typically lasted around 7.5 hours, included two aerial refuelings; F-15Es would carry a mix of air-to-air and air-to-ground munitions to perform both combat air patrol duties as well as strike missions in the same mission. Mobile SAM launchers posed a considerable threat to NATO aircraft and had made successful shoot-downs, most notably of

11562-416: The US government announced that the next generation of GPS satellites would not include the feature at all. Advances in technology and new demands on the existing system have now led to efforts to modernize the GPS and implement the next generation of GPS Block III satellites and Next Generation Operational Control System (OCX) which was authorized by the U.S. Congress in 2000. When Selective Availability

11703-453: The USAF inventory. It is also armed with AIM-9 Sidewinders and AIM-120 AMRAAMs , retaining the counter-air capabilities of its Eagle lineage, being fully capable of Offensive-Counter-Air operations. Like the F-15C, it also carries an internally mounted General Electric M61A1 20 mm cannon with 500 rounds, which is effective against enemy aircraft and "soft" ground targets. Since 2004, South Korean firm LIG Nex1 has been manufacturing

11844-407: The USAF's F-15E fleet had an average age of 21 years and an average airframe flying time of 6,000 hours. In 2012, the USAF was reportedly considering future options, with no replacement for the F-15E being slated at that time. The F-15E design would see some export success and Boeing continued developing upgrades for international customers. More radical upgrades to the air vehicle design resulted in

11985-663: The United Kingdom performed several long range strikes against IS camps and prominent figures in Libya. On 13 November 2015, a pair of F-15Es killed Abu Nabil al-Anbari , the leader of the Islamic State of Iraq and the Levant in Libya , in a strike near Darnah , Eastern Libya. On 20 February 2016, USAF F-15Es hit an IS training camp near Sabratha where foreign fighters were based, reportedly killing Noureddine Chouchane,

12126-512: The United States military. In 1964, the United States Army orbited its first Sequential Collation of Range ( SECOR ) satellite used for geodetic surveying. The SECOR system included three ground-based transmitters at known locations that would send signals to the satellite transponder in orbit. A fourth ground-based station, at an undetermined position, could then use those signals to fix its location precisely. The last SECOR satellite

12267-455: The air-to-air lethality of the F-15, and can defend itself against enemy aircraft. The F-15E prototype was a modification of the two-seat F-15B. Despite its origins, it includes significant structural changes as well as more powerful engines. The aft fuselage was designed to incorporate the more powerful engines with advanced engine bay structures and doors, which incorporate Superplastic forming and diffusion bonding technologies. The back seat

12408-590: The aircraft as a replacement for the General Dynamics F-111 and the remaining F-4s, as well as to augment the existing F-15s. In 1978, the USAF initiated the Tactical All-Weather Requirement Study, which looked at McDonnell Douglas's proposal and other options such as the purchase of further F-111Fs. The study recommended the F-15E as the USAF's future strike platform. In 1979, McDonnell Douglas and Hughes began

12549-486: The aircraft reached a maximum speed of Mach 0.9 and an altitude of 40,000 feet (12,000 m) during the 75-minute flight. This aircraft had the full F-15E avionics suite and the redesigned front fuselage, but not the aft fuselage and the common engine bay. The latter was featured on 86-0184 , while 86-0185 incorporated all the changes of the F-15E from the F-15. On 31 March 1987, the first officially completed F-15E made its first flight. The first production F-15E

12690-521: The aircrew using incorrect coordinates. An MH-47 carrying a rescue team was downed by an RPG while attempting to support the SEALs. Following refueling, the F-15Es dropped a further 11 GBU-12s in coordination with ground forces, and fired their cannons on Taliban forces in close proximity to the survivors of the downed MH-47. F-16s of 18th Fighter Squadron also made strafing passes until cannon ammunition

12831-451: The axis of the hyperboloid. The receiver is located at the point where three hyperboloids intersect. It is sometimes incorrectly said that the user location is at the intersection of three spheres. While simpler to visualize, this is the case only if the receiver has a clock synchronized with the satellite clocks (i.e., the receiver measures true ranges to the satellites rather than range differences). There are marked performance benefits to

12972-681: The basic position calculations, do not use it at all. McDonnell Douglas F-15E Strike Eagle The McDonnell Douglas (now Boeing ) F-15E Strike Eagle is an American all-weather multirole strike fighter derived from the McDonnell Douglas F-15 Eagle . The F-15E was designed in the 1980s for long-range, high-speed interdiction without relying on escort or electronic-warfare aircraft . United States Air Force (USAF) F-15E Strike Eagles can be generally distinguished from other US Eagle variants by darker aircraft camouflage , conformal fuel tanks (CFTs) mounted along

13113-648: The clocks on GPS satellites, as observed by those on Earth, run 38 microseconds faster per day than those on the Earth. The design of GPS corrects for this difference; because without doing so, GPS calculated positions would accumulate errors of up to 10 kilometers per day (6 mi/d). When the Soviet Union launched its first artificial satellite ( Sputnik 1 ) in 1957, two American physicists, William Guier and George Weiffenbach, at Johns Hopkins University 's Applied Physics Laboratory (APL) monitored its radio transmissions. Within hours they realized that, because of

13254-545: The delivery of the first 50 FLM weapons on 28 February 2008 and delivered the last of the 500 FLMs under contract in December 2013. In 2011 Boeing began testing on a laser-guided version of the baseline SDB, integrating the same Semi Active Laser (SAL) from the GBU-54 Laser JDAM. Boeing claimed to have successfully hit targets moving at 30 mph (48.3 km/h) and 50 mph (80.5 km/h). In mid-2012,

13395-496: The distance from the satellite to the ground station. With the distance information collected from multiple ground stations, the location coordinates of any satellite at any time can be calculated with great precision. Each GPS satellite carries an accurate record of its own position and time, and broadcasts that data continuously. Based on data received from multiple GPS satellites , an end user's GPS receiver can calculate its own four-dimensional position in spacetime ; However, at

13536-451: The distance traveled between two position measurements drops below or near the random error of position measurement. GPS units can use measurements of the Doppler shift of the signals received to compute velocity accurately. More advanced navigation systems use additional sensors like a compass or an inertial navigation system to complement GPS. GPS requires four or more satellites to be visible for accurate navigation. The solution of

13677-407: The effect of both SA degradation and atmospheric effects (that military receivers also corrected for). The U.S. military had also developed methods to perform local GPS jamming, meaning that the ability to globally degrade the system was no longer necessary. As a result, United States President Bill Clinton signed a bill ordering that Selective Availability be disabled on May 1, 2000; and, in 2007 ,

13818-591: The electronic warfare system of all USAF F-15s, including the F-15E, with the AN/ALQ-250 Eagle Passive/Active Warning Survivability System (EPAWSS). The first F-15E retrofitted with EPAWSS was delivered in 2022. Having a sturdier airframe rated for 8,000 hours of service life or up to 16,000 hours with proper depot maintenance programs, twice the lifetime of earlier variants, the F-15E is expected to remain in service past 2025. As of December 2012 ,

13959-535: The engine intake ramps (although CFTs can also be mounted on earlier F-15 variants) and a tandem-seat cockpit. The Strike Eagle has been deployed for military operations in Iraq , Afghanistan , Syria , and Libya , among others. During these operations, the strike fighter has carried out deep strikes against high-value targets and combat air patrols , and provided close air support for coalition troops. It has also been exported to several countries. Boeing enhanced

14100-415: The evaluation, added to the program other F-15s, designated 78-0468 , 80-0055 , and 81-0063 . The single-engined F-16XL was a promising design, which with its radically redesigned cranked-delta wing , greatly boosted performance; if selected, the single- and two-seat versions were to be designated F-16E and F-16F, respectively. On 24 February 1984, the USAF chose the F-15E; key factors in the decision were

14241-424: The fact that it was not American-made, it was not seriously considered. The DRF evaluation team, under the direction of Brigadier General Ronald W. Yates , ran from 1981 through 30 April 1983, during which the F-15E logged more than 200 flights, demonstrated takeoff weight of more than 75,000 pounds (34 t), and validated 16 different weapons-carrying configurations. McDonnell Douglas, to assist 71-0291 in

14382-542: The first batch are powered by GE F110 engines, while the second batch are powered by P&W F100 engines. The Singapore Air Force equipped their F-15SG fleet with GE F110 engines. The F-15E was first delivered to the U.S. Air Force operational units in 1988. The F-15E reached initial operational capability on 30 September 1989 at Seymour Johnson Air Force Base in North Carolina with the 4th Tactical Fighter Wing , 336th Tactical Fighter Squadron . The F-15E

14523-484: The first night, the main targets were Taliban military structures, supply depots, and al-Qaeda training camps and caves. Both the AGM-130 and GBU-15 2,000 lb (910 kg) bombs were expended; this was the GBU-15's first combat usage. GBU-24s and GBU-28s were used against reinforced targets, command and control centers and cave entrances. F-15Es often operated in pairs alongside pairs of F-16Cs. Within weeks of

14664-428: The full constellation of 24 satellites became operational in 1993. After Korean Air Lines Flight 007 was shot down when it mistakenly entered Soviet airspace, President Ronald Reagan announced that the GPS system would be made available for civilian use as of September 16, 1983; however, initially this civilian use was limited to an average accuracy of 100 meters (330 ft) by use of Selective Availability (SA),

14805-511: The ground war, F-15Es flew tank plinking missions against Iraqi vehicles in Kuwait. After 42 days of combat, a cease fire came into effect on 1 March 1991, leading to the creation of Northern and Southern no-fly zones over Iraq . Following Desert Storm, two no-fly zones over Iraq were set up, and enforced typically by US and UK aircraft. In one incident, an attack on up to 600 Kurdish refugees by Iraqi helicopters at Chamchamal , northern Iraq,

14946-407: The highest-quality signal was reserved for military use, and the signal available for civilian use was intentionally degraded, in a policy known as Selective Availability . This changed on May 1, 2000, with U.S. President Bill Clinton signing a policy directive to turn off Selective Availability to provide the same accuracy to civilians that was afforded to the military. The directive was proposed by

15087-517: The mission was cancelled mid-flight over the application of stringent Rules of Engagement. In December 1993, F-15Es launched to destroy a pair of SA-2s which had fired upon two Royal Navy Sea Harrier FRS 1s. In August 1995, F-15Es of 90th Fighter Squadron were also deployed. The 492d and 494th flew over 2,500 sorties since starting Deny Flight, 2,000 of these by 492d. In August 1995, in support of NATO's Operation Deliberate Force , F-15Es flew strike missions against Serbian armor and logistics around

15228-572: The mission. On 4 March, another incident known as the Battle of Roberts' Ridge involved several F-15Es performing a CAS mission. Aircraft destroyed a Taliban observation post and responded to nearby enemy mortar fire upon Navy SEAL forces searching for an ambushed MH-47E Chinook in the Shah-i-Kot Valley . Several bombs were dropped as the SEAL team took fire, however one bomb missed due to

15369-565: The morning of 23 September 2014, numerous American and Arab aircraft conducted air strikes in Syria against IS fighters, training compounds, headquarters and command and control facilities, storage facilities, a finance center, supply trucks, and armed vehicles. The Pentagon released videos of targets hit by ordnance deployed by F-15Es, taken by their AN/AAQ-33 Sniper targeting pods. Between August 2014 and January 2015, F-15Es flew 37 percent of all USAF sorties. USAF F-15Es based at RAF Lakenheath in

15510-543: The most significant development for safe and efficient navigation and surveillance of air and spacecraft since the introduction of radio navigation 50 years ago". Two GPS developers received the National Academy of Engineering Charles Stark Draper Prize for 2003: GPS developer Roger L. Easton received the National Medal of Technology on February 13, 2006. Francis X. Kane (Col. USAF, ret.)

15651-484: The necessary upgrades. The General Atomics MQ-20 Avenger is also planned to carry the weapon. Evidence appeared in May 2024 that Ukraine has modified MiG-29 AS fighters to carry eight GBU-39/B. The Ukrainian Air Force has used air-dropped Small Diameter Bombs since November 2023. The air-dropped Small Diameter Bomb "has proved resilient to jamming” and has a “nearly 90 percent" accuracy rate. Previously Ukraine had operated

15792-440: The new measurements are collected, the receiver uses a weighting scheme to combine the new measurements with the tracker prediction. In general, a tracker can (a) improve receiver position and time accuracy, (b) reject bad measurements, and (c) estimate receiver speed and direction. The disadvantage of a tracker is that changes in speed or direction can be computed only with a delay, and that derived direction becomes inaccurate when

15933-487: The nuclear triad, also had requirements for a more accurate and reliable navigation system. The U.S. Navy and U.S. Air Force were developing their own technologies in parallel to solve what was essentially the same problem. To increase the survivability of ICBMs, there was a proposal to use mobile launch platforms (comparable to the Soviet SS-24 and SS-25 ) and so the need to fix the launch position had similarity to

16074-422: The phrase "Not a pound for air to ground." In service, the F-15 has been a successful fighter, scoring over 100 aerial combat victories and zero losses in air-to-air combat as of 2007. Despite a lack of official interest, McDonnell Douglas had quietly included a basic secondary ground attack capability in the F-15's design since the beginning and worked on an F-15-derived interdictor fighter. The company envisaged

16215-524: The precision needed for GPS. The design of GPS is based partly on similar ground-based radio-navigation systems, such as LORAN and the Decca Navigator System , developed in the early 1940s. In 1955, Friedwardt Winterberg proposed a test of general relativity —detecting time slowing in a strong gravitational field using accurate atomic clocks placed in orbit inside artificial satellites. Special and general relativity predicted that

16356-652: The reason for the ultra-secrecy at that time. The nuclear triad consisted of the United States Navy's submarine-launched ballistic missiles (SLBMs) along with United States Air Force (USAF) strategic bombers and intercontinental ballistic missiles (ICBMs). Considered vital to the nuclear deterrence posture, accurate determination of the SLBM launch position was a force multiplier . Precise navigation would enable United States ballistic missile submarines to get an accurate fix of their positions before they launched their SLBMs. The USAF, with two thirds of

16497-408: The reference atomic clocks at the ground control stations; any drift of the clocks aboard the satellites from the reference time maintained on the ground stations is corrected regularly. Since the speed of radio waves ( speed of light ) is constant and independent of the satellite speed, the time delay between when the satellite transmits a signal and the ground station receives it is proportional to

16638-574: The requirement for moving target engagement, which favored Boeing. She was later convicted of violating a conflict of interest statute. In May 2009, Raytheon announced that it had completed its first test flight of the GBU-53/B Small Diameter Bomb II, which has a data link and a tri-mode seeker built with technology developed for the Precision Attack Missile . In August 2010 the U.S. Air Force awarded

16779-491: The source of a radio-frequency jammer to destroy it. In January 2016, the Air Force awarded a contract to Scientific Systems Co. Inc. to demonstrate the company's ImageNav technology, a vision-based navigation and precision targeting system that compares a terrain database with the host platform's sensor to make course corrections. ImageNav technology has demonstrated target geo-location and navigation precision within three meters. In January 2016, Orbital ATK revealed that

16920-407: The start of combat operations, there was a lack of targets to strike as nearly all targets had been already destroyed. The Taliban had access to SA-7 and FIM-92 Stinger portable surface-to-air missiles , posing no threat to most aircraft flying above 7,000 feet (2,100 m). Additionally, fixed SAM sites near cities as Mazar-i-Sharif and Bagram were struck early on; Afghanistan had rapidly become

17061-463: The stated cause was confusion between the air controller and the F-15E on the bombing coordinates. On 13 September 2009, an F-15E shot down a non-responsive MQ-9 Reaper drone over Northern Afghanistan to prevent it entering foreign airspace. In late 2002, during tension over suspected Iraqi possession of weapons of mass destruction , the 4th Fighter Wing at Seymour Johnson Air Force Base was ordered to maintain at least one squadron ready to deploy to

17202-403: The user carrying a clock synchronized with the satellites. Foremost is that only three satellites are needed to compute a position solution. If it were an essential part of the GPS concept that all users needed to carry a synchronized clock, a smaller number of satellites could be deployed, but the cost and complexity of the user equipment would increase. The description above is representative of

17343-432: The war: a Mil Mi-24 helicopter. While responding to a request for help by US Special Forces, five Iraqi helicopters were spotted. The lead F-15E of two, via its FLIR, acquired a helicopter in the process of unloading Iraqi soldiers, and released a GBU-10 bomb. The F-15E crew thought the bomb had missed its target and were preparing to use a Sidewinder when the helicopter was destroyed. The Special Forces team estimated that

17484-469: Was a United Nations -enforced no-fly zone over Bosnia and Herzegovina due to the deteriorating situation in the Balkans . In August 1993, F-15Es from 492nd and 494th FS deployed to Aviano , Italy . In late 1993, NATO ordered a limited F-15E strike at Udbina airfield, targeting Serbian forces in neighboring Croatia . Eight F-15Es armed with GBU-12s took off to attack an SA-6 anti-aircraft vehicle;

17625-579: Was allowed from the 1980s. Roger L. Easton of the Naval Research Laboratory , Ivan A. Getting of The Aerospace Corporation , and Bradford Parkinson of the Applied Physics Laboratory are credited with inventing it. The work of Gladys West on the creation of the mathematical geodetic Earth model is credited as instrumental in the development of computational techniques for detecting satellite positions with

17766-420: Was concerned with the curving of the paths of radio waves ( atmospheric refraction ) traversing the ionosphere from NavSTAR satellites. After Korean Air Lines Flight 007 , a Boeing 747 carrying 269 people, was shot down by a Soviet interceptor aircraft after straying in prohibited airspace because of navigational errors, in the vicinity of Sakhalin and Moneron Islands , President Ronald Reagan issued

17907-691: Was conducted when Iraq refused UNSCOM inspections. On 28 December 1998, three F-15Es struck an SA-3 tracking radar and optical guidance unit, each dropping two GBU-12 500-pound precision-guided munitions (PGMs). After Desert Fox, Iraq frequently violated the no-fly zones, thus F-15Es conducted several pre-planned retaliatory strikes; in ONW alone, weapons were expended on at least 105 days. Between 24 and 26 January 1999, F-15Es expended several AGM-130s and GBU-12s against SAM sites near Mosul , northern Iraq. They also flew in support of Operation Provide Comfort and Operation Provide Comfort II. Operation Deny Flight

18048-640: Was delivered to the 405th Tactical Training Wing , Luke Air Force Base , Arizona, in April 1988. Production continued into the 2000s with 236 produced for the USAF through 2001. The F-15E was upgraded with the Raytheon AN/APG-82(V)1 Active Electronically Scanned Array (AESA) radar after 2007, and the first test radar was delivered to Boeing in 2010. It combines the processor of the APG-79 used on

18189-403: Was depleted, then resorting to further bomb drops. The F-15Es suffered technical issues involving both radio and weapon failures, several GBU-12s were dropped before returning to Al Jaber in Kuwait. Years later, several incidents occurred. On 23 August 2007, a friendly fire incident involved an F-15E mistakenly dropping a 500 lb (230 kg) bomb on British forces, killing three soldiers;

18330-746: Was deployed in response to Iraq's invasion of Kuwait in August 1990 for Operation Desert Shield . The 336th Tactical Fighter Squadron flew to Seeb Air Base in Oman to begin training exercises in anticipation of an Iraqi attack on Saudi Arabia ; in December, the 335th and 336th squadrons relocated to Prince Sultan Air Base in Saudi Arabia, closer to Iraq's border. At the start of Operation Desert Storm , 24 F-15Es launched an attack on five fixed Scud installations in western Iraq on 17 January 1991. Missions against Scud sites continued through that night with

18471-490: Was destroyed in a launch failure). The effect of the ionosphere on radio transmission was investigated in a geophysics laboratory of Air Force Cambridge Research Laboratory , renamed to Air Force Geophysical Research Lab (AFGRL) in 1974. AFGRL developed the Klobuchar model for computing ionospheric corrections to GPS location. Of note is work done by Australian space scientist Elizabeth Essex-Cohen at AFGRL in 1974. She

18612-703: Was discontinued, GPS was accurate to about 5 meters (16 ft). GPS receivers that use the L5 band have much higher accuracy of 30 centimeters (12 in), while those for high-end applications such as engineering and land surveying are accurate to within 2 cm ( 3 ⁄ 4  in) and can even provide sub-millimeter accuracy with long-term measurements. Consumer devices such as smartphones can be accurate to 4.9 m (16 ft) or better when used with assistive services like Wi-Fi positioning . As of July 2023 , 18 GPS satellites broadcast L5 signals, which are considered pre-operational prior to being broadcast by

18753-418: Was eventually brought down by a missile of unknown origin. On 18 January, during a strike against a petrol oil and lubricant plant near Basrah , an F-15E was lost to enemy fire, killing both pilot and WSO. F-15E crews described this mission as the most difficult and dangerous of the war as it was heavily defended by SA-3s , SA-6s , SA-8s and Rolands as well as by anti-aircraft artillery. Two nights later,

18894-625: Was inducted into the U.S. Air Force Space and Missile Pioneers Hall of Fame at Lackland A.F.B., San Antonio, Texas, March 2, 2010, for his role in space technology development and the engineering design concept of GPS conducted as part of Project 621B. In 1998, GPS technology was inducted into the Space Foundation Space Technology Hall of Fame . On October 4, 2011, the International Astronautical Federation (IAF) awarded

19035-563: Was later renamed the Dual-Role Fighter (DRF) competition. The concept envisioned an aircraft capable of launching deep air interdiction missions without requiring additional support by fighter escort or jamming . General Dynamics submitted the F-16XL , while McDonnell Douglas submitted the F-15E. The Panavia Tornado was also a candidate, but since the aircraft lacked a credible air-superiority fighter capability, coupled with

19176-626: Was launched in 1969. With these parallel developments in the 1960s, it was realized that a superior system could be developed by synthesizing the best technologies from 621B, Transit, Timation, and SECOR in a multi-service program. Satellite orbital position errors, induced by variations in the gravity field and radar refraction among others, had to be resolved. A team led by Harold L. Jury of Pan Am Aerospace Division in Florida from 1970 to 1973, used real-time data assimilation and recursive estimation to do so, reducing systematic and residual errors to

19317-549: Was never considered as such by the GPS Joint Program Office (TRW may have once advocated for a different navigational system that used that acronym). With the individual satellites being associated with the name Navstar (as with the predecessors Transit and Timation), a more fully encompassing name was used to identify the constellation of Navstar satellites, Navstar-GPS . Ten " Block I " prototype satellites were launched between 1978 and 1985 (an additional unit

19458-474: Was observed by a flight of F-15Es. As they were not allowed to open fire, the F-15Es instead conducted several high speed passes as close as possible to the Iraqi helicopters to create severe wake-turbulence, while aiming lasers at the helicopter's cockpits to attempt to blind their crews; this caused the crash of one Hind. Afterwards, USAF leadership ordered F-15Es not to fly below 10,000 feet (3,000 m) to deter

19599-427: Was often expended as well as bombs from F-15Es. It was during combat over Afghanistan that four 391st crews conducted the longest fighter mission in history; lasting a total of 15.5 hours, nine of those hours spent flying over the target area. Two F-15Es attacked two Taliban command and control facilities, two buildings suspected of being used by Taliban fighters, and a road block; the F-15Es refueled 12 times during

19740-530: Was seen as justification for the billions of dollars it would cost in research, development, deployment, and operation of a constellation of navigation satellites. During the Cold War arms race , the nuclear threat to the existence of the United States was the one need that did justify this cost in the view of the United States Congress. This deterrent effect is why GPS was funded. It is also

19881-529: Was ultimately used to determine the orbit of the GPS constellation. On February 12, 2019, four founding members of the project were awarded the Queen Elizabeth Prize for Engineering with the chair of the awarding board stating: "Engineering is the foundation of civilisation; ...They've re-written, in a major way, the infrastructure of our world." The GPS satellites carry very stable atomic clocks that are synchronized with one another and with

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