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79-589: The Lockheed P-3 Orion is a four-engined, turboprop anti-submarine and maritime surveillance aircraft developed for the United States Navy and introduced in the 1960s. Lockheed based it on the L-188 Electra commercial airliner; it is easily distinguished from the Electra by its distinctive tail stinger or "MAD" boom, used for the magnetic anomaly detection (MAD) of submarines . Over

158-583: A People's Liberation Army Navy J-8II jet fighter-interceptor resulted in an international dispute between the U.S. and the People's Republic of China (PRC). More than 40 P-3 variants have demonstrated the type's rugged reliability, commonly flying 12-hour plus missions 200 ft (61 m) over water. Versions were developed for the National Oceanic and Atmospheric Administration (NOAA) for research and hurricane hunting/hurricane wall busting, for

237-724: A P-3C which had early success when on its fifth mission detected a pirate whaler with two attack skiffs. Since 2009, the Japan Maritime Self-Defense Force has deployed P-3s to Djibouti for anti-piracy patrols, from 2011 from its own base. The German Navy has also periodically contributed a P-3 to address the piracy problem. Several P-3s have been N-registered and are operated by civilian agencies. The US Customs and Border Protection has several P-3A and P-3B aircraft that are used for aircraft intercept and maritime patrol. NOAA operates two WP-3D variants specially modified for hurricane research. One P-3, N426NA,

316-540: A Pakistani Naval station in Karachi. In June 2011, the U.S. agreed to replace the destroyed aircraft with two new ones. In February 2012, the U.S. delivered two additional P-3Cs to the Pakistan Navy. On 18 November 2016, during tensions with India, the Pakistan Navy dispatched various ASW units, including P-3Cs, in response to reports of an Indian Navy submarine that was allegedly loitering in close proximity to

395-534: A U.S. Navy P-3B of VP-26 was downed by anti-aircraft fire in the Gulf of Thailand with the loss of the entire crew. Two months earlier in February 1968, another one of VP-26's P-3Bs was operating in the same vicinity when it crashed with the loss of the entire crew. Originally attributed to a low altitude mishap, later conjecture is that this aircraft may have also fallen victim to anti-aircraft artillery (AAA) fire from

474-406: A constant-speed propeller increase their pitch as aircraft speed increases. Another benefit of this type of propeller is that it can also be used to generate reverse thrust to reduce stopping distance on the runway. Additionally, in the event of an engine failure, the propeller can be feathered , thus minimizing the drag of the non-functioning propeller. While the power turbine may be integral with

553-416: A large amount of air by a small degree than a small amount of air by a large degree, a low disc loading (thrust per unit disc area) increases the aircraft's energy efficiency , and this reduces the fuel use. Propellers work well until the flight speed of the aircraft is high enough that the airflow past the blade tips reaches the speed of sound. Beyond that speed, the proportion of the power that drives

632-465: A more advanced aircraft to conduct maritime patrol and antisubmarine warfare. Modifying an existing aircraft should save on cost and to allow rapid introduction into the fleet. Lockheed suggested a military version of its L-188 Electra , then still in development and yet to fly. In April 1958, Lockheed won the competition and was awarded an initial research-and-development contract in May. Lockheed modified

711-411: A more pointed nose radome , a distinctive tail "stinger" for detection of submarines by MAD, wing hardpoints, and other internal, external, and airframe-production technique enhancements. The Orion has four Allison T56 turboprops , which give it a top speed of 411 knots (761  km/h ; 473  mph ) comparable to the fastest propeller fighters, or even to slow high-bypass turbofan jets such as

790-1008: A test center in California, an oceanographic development squadron in Maryland, and two active duty "special projects" units in Maine and Hawaii, the latter being slightly smaller than a typical squadron. In fiscal year 1995, the U.S. Navy planned to reduce active-duty patrol squadrons from sixteen to thirteen—seven on the East Coast, six on the West. The patrol squadrons planned to survive were VP-8, 10, 11, and 26 at NAS Brunswick , Maine, and VP-5 , 16, and 45 at NAS Jacksonville , Florida. The Pacific squadrons that were to be retained were VP-1, 4, 9, and 47 at Barbers' Point, Hawaii, and 40 and VP-46 at NAS Whidbey Island , Washington. Thus Patrol Squadrons 17, 23, 24, and 49 were to be disestablished, and

869-591: A test-bed not intended for production. It first flew on 20 September 1945. From their experience with the Trent, Rolls-Royce developed the Rolls-Royce Clyde , the first turboprop engine to receive a type certificate for military and civil use, and the Dart , which became one of the most reliable turboprop engines ever built. Dart production continued for more than fifty years. The Dart-powered Vickers Viscount

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948-429: Is a turbine engine that drives an aircraft propeller . A turboprop consists of an intake , reduction gearbox , compressor , combustor , turbine , and a propelling nozzle . Air enters the intake and is compressed by the compressor. Fuel is then added to the compressed air in the combustor, where the fuel-air mixture then combusts . The hot combustion gases expand through the turbine stages, generating power at

1027-482: Is normally a constant-speed (variable pitch) propeller type similar to that used with larger aircraft reciprocating engines , except that the propeller-control requirements are very different. Due to the turbine engine's slow response to power inputs, particularly at low speeds, the propeller has a greater range of selected travel in order to make rapid thrust changes, notably for taxi, reverse, and other ground operations. The propeller has 2 modes, Alpha and Beta. Alpha

1106-448: Is primarily used for pinpointing the location of a submarine immediately prior to a torpedo or depth bomb attack. Due to the sensitivity of the detector, electromagnetic noise can interfere with it, so the detector is placed in P-3's fiberglass tail stinger (MAD boom), far from other electronics and ferrous metals on the aircraft. The crew complement varies depending on the role being flown,

1185-494: Is sacrificed in favor of shaft power, which is obtained by extracting additional power (beyond that necessary to drive the compressor) from turbine expansion. Owing to the additional expansion in the turbine system, the residual energy in the exhaust jet is low. Consequently, the exhaust jet produces about 10% of the total thrust. A higher proportion of the thrust comes from the propeller at low speeds and less at higher speeds. Turboprops have bypass ratios of 50–100, although

1264-404: Is the mode for all flight operations including takeoff. Beta, a mode typically consisting of zero to negative thrust, is used for all ground operations aside from takeoff. The Beta mode is further broken down into 2 additional modes, Beta for taxi and Beta plus power. Beta for taxi as the name implies is used for taxi operations and consists of all pitch ranges from the lowest alpha range pitch, all

1343-486: Is used by National Aeronautics and Space Administration (NASA) as an Earth science research platform, primarily for the NASA Science Mission Directorate 's Airborne Science Program; it is based at Goddard Space Flight Center 's Wallops Flight Facility , Virginia . Aero Union, Inc. operated eight secondhand P-3As configured as air tankers, which were leased to the U.S. Forest Service ,

1422-684: The Boeing P-8 Poseidon , a Boeing 737 variant, which entered service in 2013. The P-3 has an internal bomb bay under the front fuselage , which can house conventional Mark 50 torpedoes or Mark 46 torpedoes and/or special ( nuclear ) weapons. Additional underwing stations, or pylons, can carry other armament configurations, including the AGM-84 Harpoon , AGM-84E SLAM , AGM-84H/K SLAM-ER, AGM-65 Maverick , 127 millimetres (5.0 in) Zuni rockets , and various other sea mines , missiles, and gravity bombs. The aircraft also had

1501-621: The California Department of Forestry and Fire Protection and other agencies for firefighting use. Several of these aircraft were involved in the U.S. Forest Service airtanker scandal but have not been involved in any catastrophic aircraft mishaps. Aero Union has since gone bankrupt, and their P-3s have been put up for auction. Over the years, numerous variants of the P-3 have been created. A few notable examples are: [REDACTED]   United States [REDACTED]   Pahlavi Iran Turboprop A turboprop

1580-531: The EP-3 Aries signals intelligence (SIGINT) variant at Naval Air Station Whidbey Island, Washington. In January 2011, the U.S. Navy revealed that P-3s have been used to hunt down "third generation" narco-submarines . This is significant because as recently as July 2009, fully submersible submarines have been used in smuggling operations. As of November 2013, the US Navy began phasing out the P-3 in favor of

1659-961: The Fairchild Republic A-10 Thunderbolt II or the Lockheed S-3 Viking . Similar patrol aircraft include the Soviet Ilyushin Il-38 , the French Breguet Atlantique and the British jet-powered Hawker Siddeley Nimrod (based on the de Havilland Comet ). The first production version, designated P3V-1, was launched on 15 April 1961. Initial squadron deliveries to Patrol Squadron Eight ( VP-8 ) and Patrol Squadron Forty-Four (VP-44) at Naval Air Station Patuxent River , Maryland, began in August 1962. On 18 September 1962,

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1738-634: The P-3 Orion , and the C-130 Hercules military transport aircraft. The first turbine-powered, shaft-driven helicopter was the Kaman K-225 , a development of Charles Kaman 's K-125 synchropter , which used a Boeing T50 turboshaft engine to power it on 11 December 1951. December 1963 saw the first delivery of Pratt & Whitney Canada's PT6 turboprop engine for the then Beechcraft 87, soon to become Beechcraft King Air . 1964 saw

1817-841: The Piper Meridian , Socata TBM , Pilatus PC-12 , Piaggio P.180 Avanti , Beechcraft King Air and Super King Air . In April 2017, there were 14,311 business turboprops in the worldwide fleet. Between 2012 and 2016, the ATSB observed 417 events with turboprop aircraft, 83 per year, over 1.4 million flight hours: 2.2 per 10,000 hours. Three were "high risk" involving engine malfunction and unplanned landing in single‑engine Cessna 208 Caravans , four "medium risk" and 96% "low risk". Two occurrences resulted in minor injuries due to engine malfunction and terrain collision in agricultural aircraft and five accidents involved aerial work: four in agriculture and one in an air ambulance . Jane's All

1896-614: The Tupolev Tu-114 can reach 470 kn (870 km/h; 540 mph). Large military aircraft , like the Tupolev Tu-95 , and civil aircraft , such as the Lockheed L-188 Electra , were also turboprop powered. The Airbus A400M is powered by four Europrop TP400 engines, which are the second most powerful turboprop engines ever produced, after the 11 MW (15,000 hp) Kuznetsov NK-12 . In 2017,

1975-1089: The U.S. Customs Service (now U.S. Customs and Border Protection ) for drug interdiction and aerial surveillance mission with a rotodome adapted from the Grumman E-2 Hawkeye or an AN/APG-66 radar adapted from the General Dynamics F-16 Fighting Falcon , and for NASA for research and development. The U.S. Navy remains the largest P-3 operator, currently distributed between a single fleet replacement (i.e., "training") patrol squadron in Florida (VP-30), 12 active duty patrol squadrons distributed between bases in Florida, Washington and Hawaii, two Navy Reserve patrol squadrons in Florida and Washington, one active duty special projects patrol squadron (VPU-2) in Hawaii, and two active duty test and evaluation squadrons. One additional active duty fleet reconnaissance squadron (VQ-1) operates

2054-797: The "Decade in the Desert", Navy P-3Cs patrolled combat zones in the Middle East and Southwest Asia. From the start of the war in Afghanistan, U.S. Navy P-3s operated from Kandahar in that role. Royal Australian Air Force AP-3Cs operated out of Minhad Air Base in the UAE from 2003 until their withdrawal in November 2012. Between 2008 and 2012, AP-3Cs conducted overland intelligence, surveillance and reconnaissance tasks in support of coalition troops across Afghanistan. The United States Geological Survey used

2133-517: The 7 January 1991 commencement of Operation Desert Storm , a P-3C equipped with an APS-137 Inverse Synthetic Aperture Radar (ISAR) conducted coastal surveillance along Iraq and Kuwait to provide pre-strike reconnaissance on enemy military installations. A total of 55 of the 108 Iraqi vessels destroyed during the conflict were targeted by P-3Cs. The P-3's mission expanded in the late 1990s and early 2000s to include battlespace surveillance both at sea and over land. The long range and long loiter time of

2212-820: The IIAF was renamed the Islamic Republic of Iran Air Force (IRIAF). They were used in the Tanker War phase of the Iran–Iraq War . A total of four P-3Fs remain in service. Three P-3C Orions, delivered to the Pakistan Navy in 1996 and 1997 were operated extensively during the Kargil conflict . After the crash of one with the loss of an entire crew, the type was grounded; nonetheless, the aircraft were maintained in an armed state and airworthy condition throughout

2291-562: The Orion to survey parts of southern and eastern Afghanistan for lithium, copper, and other mineral deposits. Several U.S. Navy P-3Cs, and two Canadian CP-140 Auroras , a variant of the Orion, participated in maritime surveillance missions over Libyan waters in the framework of enforcement of the 2011 no-fly zone over Libya. A U.S. Navy P-3C supporting Operation Odyssey Dawn engaged the Libyan coast guard vessel Vittoria on 28 March 2011 after

2370-783: The P-3 Orion. Project A-NEW was the engineering system, which after several early trials, produced the engineering prototype, the CP-823/U , Univac 1830 , Serial A-1, A-NEW MOD3 Computing System. Univac delivered the CP-823/U to the Naval Air Development Center at Johnsville, Pennsylvania, in 1965; this directly led to the production computers later equipped on the P-3C. Three civilian Electras were lost in fatal accidents between February 1959 and March 1960. Following

2449-532: The P-3 proved to be an invaluable asset during Operation Iraqi Freedom and Operation Enduring Freedom , being able to instantaneously provide the gathered battlespace information to ground troops, particularly the U.S. Marines. Although the P-3 is a MPA, armament and sensor upgrades in the Anti-surface Warfare Improvement Program (AIP) have made it suitable for sustained combat air support over land. In what became known as

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2528-511: The P-3C. By July 2023, only VQ-1 and VXS-1 continued to operate variants of the P-3C, with the retirement of VQ-1's EP-3E Aries II fleet expected in 2025. In October 1962, P-3As flew several blockade patrols in the vicinity of Cuba. Having only joined the operational Fleet earlier that year, this event marked the first employment of the P-3 in a real world "heightened threat" situation. Beginning in 1964, forward deployed P-3s began flying various missions under Operation Market Time from bases in

2607-520: The PPC or TACCO will be designated as the aircraft Mission Commander (MC). Once on station, one engine is often shut down (usually the No. 1 engine – the left outer engine) to conserve fuel and extend the time aloft and/or range when at low level. It is the primary candidate for loiter shutdown because it has no generator. Eliminating the exhaust from engine 1 also improves visibility from the aft observer station on

2686-545: The Philippines and Vietnam. The primary focus of these coastal patrols was to stem the supply of materials to the Viet Cong by sea, although several of these missions also became overland "feet dry" sorties. During one such mission, a small caliber artillery shell passed through a P-3 without rendering it mission incapable. The only confirmed combat loss of a P-3 also occurred during Operation Market Time. In April 1968,

2765-700: The Southern territorial waters of Pakistan in the Arabian Sea . This submarine was swiftly intercepted by the Navy Orions and forced away from the territorial boundaries. The Spanish Air Force deployed P-3s to assist the international effort against piracy in Somalia . On 29 October 2008, a Spanish P-3 patrolling Somalia's coast reacted to a distress call from an oil tanker in the Gulf of Aden ; it overflew

2844-533: The Soviet Union had the technology to create the airframe for a jet-powered strategic bomber comparable to Boeing's B-52 Stratofortress , they instead produced the Tupolev Tu-95 Bear, powered with four Kuznetsov NK-12 turboprops, mated to eight contra-rotating propellers (two per nacelle) with supersonic tip speeds to achieve maximum cruise speeds in excess of 575 mph, faster than many of

2923-430: The U.S. military transitioned to a unified designation system for all services, with the aircraft being renamed the P-3 Orion. Paint schemes have changed from early 1960s, gloss seaplane gray and white to mid-1960s/1970s/1980s/early 1990s gloss white and gray, to mid-1990s flat-finish low-visibility gray with fewer and smaller markings. In the early 2000s, the paint scheme changed to its current overall gloss gray finish with

3002-526: The United States military has been using for more than 50 years. In the twenty-first century, the turbofan-powered Boeing P-8 Poseidon began to supplement, and will eventually replace, the U.S. Navy's P-3s. In August 1957, the U.S. Navy called for proposals for replacement of the piston-engined Lockheed P2V Neptune (later redesignated P-2) and Martin P5M Marlin (later redesignated P-5) with

3081-550: The World's Aircraft . 2005–2006. Bureau of Naval Weapons As aviation technology became increasingly complex after World War II , the Navy increasingly realized the need for better integration between its aircraft and aerial weapons. This was also to end the conflict between bureaus due to technological convergence; BuOrd's work in guided missiles , for example, was overlapping with BuAer's work on unmanned aircraft . BuWeps

3160-605: The aircraft's poor reputation in an era in which turboprop-powered aircraft were being replaced by faster jets. In military roles that valued fuel efficiency more than speed, the Orion remained in service for over 50 years after its 1962 introduction. Although surpassed in production longevity by the Lockheed C-130 Hercules , 734 P-3s were produced through 1990. Lockheed Martin opened a new P-3 wing production-line in 2008 as part of its Service Life Extension Program (ASLEP) for delivery in 2010. A complete ASLEP replaces

3239-516: The capability to carry the AGM-12 Bullpup guided missile until that weapon was withdrawn from U.S./ NATO /Allied service. The P-3 is equipped with a MAD in the extended tail. This instrument is able to detect the magnetic anomaly of a submarine in the Earth's magnetic field. The limited range of this instrument requires the aircraft to be near the submarine at low altitude. Because of this, it

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3318-514: The coalition air campaign's start, "Outlaw Hunter" detected a large number of Iraqi patrol boats and naval vessels attempting to move from Basra and Umm Qasr to Iranian waters. "Outlaw Hunter" vectored in strike elements which attacked the flotilla near Bubiyan Island , destroying 11 vessels and damaging scores more. During Desert Shield, a P-3 using infrared imaging detected a ship with Iraqi markings beneath freshly-painted bogus Egyptian markings trying to avoid detection. Several days before

3397-417: The compressor intake is at the aft of the engine, and the exhaust is situated forward, reducing the distance between the turbine and the propeller. Unlike the small-diameter fans used in turbofan engines, the propeller has a large diameter that lets it accelerate a large volume of air. This permits a lower airstream velocity for a given amount of thrust. Since it is more efficient at low speeds to accelerate

3476-459: The control system. The turboprop system consists of 3 propeller governors , a governor, and overspeed governor, and a fuel-topping governor. The governor works in much the same way a reciprocating engine propeller governor works, though a turboprop governor may incorporate beta control valve or beta lift rod for beta operation and is typically located in the 12 o'clock position. There are also other governors that are included in addition depending on

3555-514: The escalation period of 2001 and 2002. During 2007, they were used by the navy to conduct signals intelligence, airborne and bombing operations in a Swat offensive and Operation Rah-e-Nijat . Precision and strategic bombing missions were carried out by the P-3Cs; intelligence management operations were also conducted against Taliban and al-Qaeda operatives. On 22 May 2011, two out of the four Pakistani P-3Cs were destroyed in an attack on PNS Mehran ,

3634-499: The first jet aircraft and comparable to jet cruising speeds for most missions. The Bear would serve as their most successful long-range combat and surveillance aircraft and symbol of Soviet power projection through to the end of the 20th century. The USA used turboprop engines with contra-rotating propellers, such as the Allison T40 , on some experimental aircraft during the 1950s. The T40-powered Convair R3Y Tradewind flying-boat

3713-564: The first deliveries of the Garrett AiResearch TPE331 , (now owned by Honeywell Aerospace ) on the Mitsubishi MU-2 , making it the fastest turboprop aircraft for that year. In contrast to turbofans , turboprops are most efficient at flight speeds below 725 km/h (450 mph; 390 knots) because the jet velocity of the propeller (and exhaust) is relatively low. Modern turboprop airliners operate at nearly

3792-570: The gas generator section, many turboprops today feature a free power turbine on a separate coaxial shaft. This enables the propeller to rotate freely, independent of compressor speed. Alan Arnold Griffith had published a paper on compressor design in 1926. Subsequent work at the Royal Aircraft Establishment investigated axial compressor-based designs that would drive a propeller. From 1929, Frank Whittle began work on centrifugal compressor-based designs that would use all

3871-460: The gas power produced by the engine for jet thrust. The world's first turboprop was designed by the Hungarian mechanical engineer György Jendrassik . Jendrassik published a turboprop idea in 1928, and on 12 March 1929 he patented his invention. In 1938, he built a small-scale (100 Hp; 74.6 kW) experimental gas turbine. The larger Jendrassik Cs-1 , with a predicted output of 1,000 bhp,

3950-623: The historic "Replacement Air Group" nomenclature) were located in California and Florida. The since-deactivated VP-31 in California provided P-3 training for the Pacific Fleet, while VP-30 in Florida performed the task for the Atlantic Fleet. These squadrons were also augmented by a test and evaluation squadron in Maryland, two additional test and evaluation units that were part of an air development center in Pennsylvania and

4029-546: The left side of the aircraft. On occasion, both outboard engines can be shut down, weight, weather, and fuel permitting. Long, deep-water, coastal, or border-patrol missions can last over 10 hours and may include extra crew. The record time aloft for a P-3 is 21.5 hours, undertaken by the Royal New Zealand Air Force 's No. 5 Squadron in 1972. Developed during the Cold War , the P-3's primary mission

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4108-406: The model, such as an overspeed and fuel topping governor on a Pratt & Whitney Canada PT6 , and an under-speed governor on a Honeywell TPE331 . The turboprop is also distinguished from other kinds of turbine engine in that the fuel control unit is connected to the governor to help dictate power. To make the engine more compact, reverse airflow can be used. On a reverse-flow turboprop engine,

4187-671: The most widespread turboprop airliners in service were the ATR 42 / 72 (950 aircraft), Bombardier Q400 (506), De Havilland Canada Dash 8 -100/200/300 (374), Beechcraft 1900 (328), de Havilland Canada DHC-6 Twin Otter (270), Saab 340 (225). Less widespread and older airliners include the BAe Jetstream 31 , Embraer EMB 120 Brasilia , Fairchild Swearingen Metroliner , Dornier 328 , Saab 2000 , Xian MA60 , MA600 and MA700 , Fokker 27 and 50 . Turboprop business aircraft include

4266-617: The newer and more advanced Boeing P-8 Poseidon. In May 2020, Patrol Squadron 40 completed the transition to the P-8, marking the retirement of the P-3C from U.S. Navy active duty service. The last of the active-duty P-3Cs, aircraft 162776, was also delivered to the Naval Aviation Museum in Pensacola, Florida . Two Navy Reserve squadrons, Air Test and Evaluation Squadron 30 and One Active duty Squadron ( VQ-1 ) continued to fly

4345-431: The original full-sized color markings. However, large-sized BuNos on the vertical stabilizer and squadron designations on the fuselage remained largely omitted. In 1963, the U.S. Navy's Bureau of Naval Weapons contracted Univac Defense Systems Division of Sperry Rand to engineer, build, and test a digital computer (a device then in its infancy) to interface with the many sensors and newly developing display units of

4424-507: The outer wings, center-wing lower section, and horizontal stabilizers with newly built parts. In the 1990s, the U.S. Navy attempted to procure a successor aircraft to the P-3, and selected the improved P-7 over a naval-specific variant of the twin turbofan-powered Boeing 757 , but this program was subsequently cancelled. In a second program to select a replacement, the advanced Lockheed Martin Orion 21, another P-3-derived aircraft, lost out to

4503-416: The pilot not being able to see out of the rear of the aircraft for backing and the amount of debris reverse stirs up, manufacturers will often limit the speeds beta plus power may be used and restrict its use on unimproved runways. Feathering of these propellers is performed by the propeller control lever. The constant-speed propeller is distinguished from the reciprocating engine constant-speed propeller by

4582-532: The pirate vessels three times, dropping a smoke bomb on each pass, as they attempted to board the tanker. After the third pass, the pirates broke off their attack. On 29 March 2009, the same P-3 pursued the assailants of the German navy tanker Spessart  (A1442) , resulting in the pirate's capture. In April 2011, the Portuguese Air Force also contributed to Operation Ocean Shield by sending

4661-403: The point of exhaust. Some of the power generated by the turbine is used to drive the compressor and electric generator . The gases are then exhausted from the turbine. In contrast to a turbojet or turbofan , the engine's exhaust gases do not provide enough power to create significant thrust, since almost all of the engine's power is used to drive the propeller. Exhaust thrust in a turboprop

4740-494: The propeller that is converted to propeller thrust falls dramatically. For this reason turboprop engines are not commonly used on aircraft that fly faster than 0.6–0.7 Mach , with some exceptions such as the Tupolev Tu-95 . However, propfan engines, which are very similar to turboprop engines, can cruise at flight speeds approaching 0.75 Mach. To maintain propeller efficiency across a wide range of airspeeds, turboprops use constant-speed (variable-pitch) propellers. The blades of

4819-419: The propeller. This allows for propeller strike or similar damage to occur without damaging the gas generator and allowing for only the power section (turbine and gearbox) to be removed and replaced in such an event, and also allows for less stress on the start during engine ground starts. Whereas a fixed shaft has the gearbox and gas generator connected, such as on the Honeywell TPE331 . The propeller itself

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4898-399: The propulsion airflow is less clearly defined for propellers than for fans. The propeller is coupled to the turbine through a reduction gear that converts the high RPM /low torque output to low RPM/high torque. This can be of two primary designs, free-turbine and fixed. A free-turbine turboshaft found on the Pratt & Whitney Canada PT6 , where the gas generator is not connected to

4977-404: The prototype YP3V-1/YP-3A, Bureau Number (BuNo) 148276 from the third Electra airframe c/n 1003. The first flight of the aircraft's aerodynamic prototype, originally designated YP3V-1, took place on 19 August 1958. While based on the same design philosophy as the Electra, the aircraft differed structurally; it had 7 feet (2.1 m) less fuselage forward of the wings with an opening bomb bay, and

5056-449: The remaining units were to operate nine aircraft instead of eight, augmented by VP-30 and the nine-at-the-time USNR P-3 squadrons. Reconnaissance missions in international waters led to occasions where Soviet fighters would "bump" a P-3, either operated by the U.S. Navy or other operators such as the Royal Norwegian Air Force . On 1 April 2001, a midair collision between a United States Navy EP-3E ARIES II signals surveillance aircraft and

5135-500: The same source as the April incident. On 2 August 1990, Iraq invaded Kuwait and was poised to strike Saudi Arabia. Within 48 hours of the initial invasion, U.S. Navy P-3Cs were among the first American forces to arrive in the area. One was a modified platform with a prototype over-the-horizon targeting (OTH-T) system package known as "Outlaw Hunter"; it had been undergoing trials in the Pacific after being developed by Tiburon Systems, Inc. for NAVAIR's PMA-290 Program Office. Within hours of

5214-529: The same speed as small regional jet airliners but burn two-thirds of the fuel per passenger. Compared to piston engines, their greater power-to-weight ratio (which allows for shorter takeoffs) and reliability can offset their higher initial cost, maintenance and fuel consumption. As jet fuel can be easier to obtain than avgas in remote areas, turboprop-powered aircraft like the Cessna Caravan and Quest Kodiak are used as bush airplanes . Turboprop engines are generally used on small subsonic aircraft, but

5293-434: The third crash, the FAA restricted the maximum speed of Electras pending determination of the causes. After an extensive investigation, two of the crashes (those of September 1959 and March 1960) were identified as due to insufficiently strong engine mounts, unable to damp a whirling motion that could affect the outboard engines. When the oscillation was transmitted to the wings, a severe vertical vibration escalated, tearing off

5372-550: The variant being operated, and the country that is operating the type. In U.S. Navy service, the normal crew complement was 12 until it was reduced to its current complement of 11 in the early 2000s when the in-flight ordnanceman position was eliminated as a cost-savings measure and the ORD duties assumed by the in-flight technician. Data for U.S. Navy P-3C only. Officers: NOTE: NAVCOM on P-3C only; USN P-3A and P-3B series had an NFO Navigator (TACNAV) and an enlisted Airborne Radio Operator (RO) Enlisted aircrew: The senior of either

5451-436: The vessel and eight smaller craft fired on merchant ships in the port of Misrata , Libya. The Orion fired AGM-65 Maverick missiles on Vittoria , which was subsequently beached. Lockheed produced the P-3F variant of the P-3 Orion for Pahlavi Iran . Six examples were delivered to the former Imperial Iranian Air Force (IIAF) in 1975 and 1976. Following the Iranian Revolution in 1979, the Orions continued in service, after

5530-410: The way down to zero pitch, producing very little to zero-thrust and is typically accessed by moving the power lever to a beta for taxi range. Beta plus power is a reverse range and produces negative thrust, often used for landing on short runways where the aircraft would need to rapidly slow down, as well as backing operations and is accessed by moving the power lever below the beta for taxi range. Due to

5609-555: The wings. The company implemented a costly modification program, labelled the Lockheed Electra Achievement Program, which strengthened the engine mounts and the wing structures supporting the mounts, and replaced some wing skins with thicker material. At its own expense, Lockheed modified all surviving Electras of the 145 built at that time, the process taking 20 days for each aircraft. These changes were incorporated into subsequent aircraft as they were built. The Electra's sales were limited as Lockheed's technical fix did not completely erase

5688-551: The years, the P-3 has seen numerous design developments, most notably in its electronics packages. Numerous navies and air forces around the world continue to use the type primarily for maritime patrol , reconnaissance , anti-surface warfare and anti-submarine warfare. A total of 757 P-3s have been built. In 2012, it joined the handful of military aircraft including the Boeing B-52 Stratofortress , Boeing KC-135 Stratotanker , and Lockheed C-130 Hercules that

5767-403: Was destroyed in a bombing raid. In 1941, the engine was abandoned due to war, and the factory converted to conventional engine production. The first mention of turboprop engines in the general public press was in the February 1944 issue of the British aviation publication Flight , which included a detailed cutaway drawing of what a possible future turboprop engine could look like. The drawing

5846-714: Was operated by the U.S. Navy for a short time. The first American turboprop engine was the General Electric XT31 , first used in the experimental Consolidated Vultee XP-81 . The XP-81 first flew in December 1945, the first aircraft to use a combination of turboprop and turbojet power. The technology of Allison's earlier T38 design evolved into the Allison T56 , used to power the Lockheed Electra airliner, its military maritime patrol derivative

5925-647: Was produced and tested at the Ganz Works in Budapest between 1937 and 1941. It was of axial-flow design with 15 compressor and 7 turbine stages, annular combustion chamber. First run in 1940, combustion problems limited its output to 400 bhp. Two Jendrassik Cs-1s were the engines for the world's first turboprop aircraft – the Varga RMI-1 X/H . This was a Hungarian fighter-bomber of WWII which had one model completed, but before its first flight it

6004-603: Was the first turboprop aircraft of any kind to go into production and sold in large numbers. It was also the first four-engined turboprop. Its first flight was on 16 July 1948. The world's first single engined turboprop aircraft was the Armstrong Siddeley Mamba -powered Boulton Paul Balliol , which first flew on 24 March 1948. The Soviet Union built on German World War II turboprop preliminary design work by Junkers Motorenwerke, while BMW, Heinkel-Hirth and Daimler-Benz also worked on projected designs. While

6083-804: Was to localize Soviet Navy ballistic missile and fast attack submarines detected by undersea surveillance systems and eliminate them in the event of full-scale war. At its height, the U.S. Navy's P-3 community consisted of twenty-four active duty "Fleet" patrol squadrons home based at air stations in the states of Florida and Hawaii as well as bases which formerly had P-3 operations in Maryland, Maine, and California. There were also thirteen Naval Reserve patrol squadrons identical to their active duty "Fleet" counterparts, said Reserve "Fleet" squadrons being based in Florida, Pennsylvania, Maryland, Michigan, Massachusetts (later relocated to Maine), Illinois, Tennessee, Louisiana, California and Washington. Two Fleet Replacement Squadrons (FRS), also called "RAG" squadrons (from

6162-455: Was under the command of a two-star admiral known as the Chief, BuWeps. Four individuals served in this position: The establishment of BuWeps represented only a temporary solution to the Navy's needs. In the mid-1960s, the Navy completely revised its material organization, replacing the bureau system with "Systems Commands" ( SYSCOMs ). BuWeps was disestablished May 1, 1966 and replaced with

6241-488: Was very close to what the future Rolls-Royce Trent would look like. The first British turboprop engine was the Rolls-Royce RB.50 Trent , a converted Derwent II fitted with reduction gear and a Rotol 7 ft 11 in (2.41 m) five-bladed propeller. Two Trents were fitted to Gloster Meteor EE227 — the sole "Trent-Meteor" — which thus became the world's first turboprop-powered aircraft to fly, albeit as

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