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The MD Helicopters MD Explorer is a light twin-engined utility
helicopter A helicopter is a type of rotorcraft in which Lift (force), lift and thrust are supplied by horizontally spinning Helicopter rotor, rotors. This allows the helicopter to VTOL, take off and land vertically, to hover (helicopter), hover, and ...
designed and initially produced by the American rotorcraft specialist McDonnell Douglas Helicopter Systems. On 18 December 1992, the
maiden flight The maiden flight, also known as first flight, of an aircraft is the first occasion on which it leaves the ground under its own power. The same term is also used for the first launch of rockets. In the early days of aviation it could be dange ...
was conducted, initial certification for the type followed roughly two years later. The initial model, the MD 900, was joined by an improved successor, the MD 902, during the late 1990s. The Explorer is currently produced by
MD Helicopters MD Helicopters, LLC. (formerly McDonnell Douglas Helicopter Systems) is an American aerospace manufacturer. It produces light utility helicopters for commercial and military use. The company was a subsidiary of Hughes Aircraft until 1984, when Mc ...
. The helicopter is noted for having no tail rotor, using the NOTAR technology instead, giving its tail a unique appearance and quieter sound profile than a more traditional tail rotor.


Development

In January 1989, McDonnell Douglas Helicopters officially announced the launch of the Explorer, which it initially referred to as the ''MDX''. Amongst other things, the Explorer was the first McDonnell Douglas helicopter to incorporate the
NOTAR NOTAR ("no tail rotor") is a helicopter system which avoids the use of a tail rotor. It was developed by MD Helicopters, McDonnell Douglas Helicopter Systems (through their acquisition of Hughes Helicopters). The system uses a fan inside the tail ...
system from its initial design.Frawley 2003, p. 156. McDonnell Douglas partnered with Hawker de Havilland of Australia, which handled the manufacturing of the airframes. A total of ten
prototype A prototype is an early sample, model, or release of a product built to test a concept or process. It is a term used in a variety of contexts, including semantics, design, electronics, and Software prototyping, software programming. A prototype ...
s were constructed, seven of which being used for ground-based tests. McDonnell Douglas Helicopters became a launch customer for
Pratt & Whitney Canada Pratt & Whitney Canada (PWC or P&WC) is a Canada-based aircraft engine manufacturer. PWC's headquarters are in Longueuil, Quebec, south of Montreal. It is a division of the larger US-based Pratt & Whitney (P&W), itself a business unit of RTX ...
's PW200
turboshaft A turboshaft engine is a form of gas turbine that is optimized to produce shaft horsepower rather than jet thrust. In concept, turboshaft engines are very similar to turbojets, with additional turbine expansion to extract heat energy from the ex ...
engines, for which it had an exclusive agreement to power the first 128 Explorers with pairs of PW206As. While plans had been mooted to offer the
Turbomeca Arrius The Turbomeca Arrius is one of a family of turboshaft engines for helicopter use, first produced in 1981. As of 2012, some 2,700 units had been sold. Power ranges between 357 kW (479 shp) and 530 kW (716 shp) for different versions. F ...
powerplant as an alternative option, these were subsequently discarded. On 18 December 1992, the
maiden flight The maiden flight, also known as first flight, of an aircraft is the first occasion on which it leaves the ground under its own power. The same term is also used for the first launch of rockets. In the early days of aviation it could be dange ...
of the Explorer took place, performed by ship #2 (N900MD). On 2 December 1994,
Federal Aviation Administration The Federal Aviation Administration (FAA) is a Federal government of the United States, U.S. federal government agency within the United States Department of Transportation, U.S. Department of Transportation that regulates civil aviation in t ...
(FAA) certification for the Explorer was granted, permitting its use in North America;
Joint Aviation Authorities The Joint Aviation Authorities (JAA) was an associated body of the European Civil Aviation Conference representing the civil aviation regulatory authorities of a number of European States who had agreed to co-operate in developing and implementi ...
(JAA) certification was received shortly thereafter. However, certification of the Explorer's
instrument flight rules In aviation, instrument flight rules (IFR) is one of two sets of regulations governing all aspects of civil aviation aircraft operations; the other is visual flight rules (VFR). The U.S. Federal Aviation Administration's (FAA) ''Instrument Fl ...
(IFR) capability was protracted due to technical difficulties with integration; in February 1997, FAA certification for IFR operations was finally received. On 29 May 1997, all Explorers were temporarily grounded following the discovery of a broken drive-link; during the following month, flight operations resumed after the FAA gave its approval of a redesigned component that addressed the issue. During September 1997, a range of improvements to the Explorer were introduced. These included the availability of the PW206E engine, which had a higher single engine inoperative rating, along with revised engine air inlets, improved NOTAR inlet design, and a more powerful stabiliser control system. The benefits were improvements to both range and endurance, along with an increased maximum takeoff weight. This enhanced Explorer was unofficially designated the MD 902. In May 1998, it was reported that
Bell Helicopters Bell Textron Inc. is an American aerospace manufacturer headquartered in Fort Worth, Texas. A subsidiary of Textron, Bell manufactures military rotorcraft at facilities in Fort Worth, and Amarillo, Texas, United States as well as commercial heli ...
, as part of a wider deal with
Boeing The Boeing Company, or simply Boeing (), is an American multinational corporation that designs, manufactures, and sells airplanes, rotorcraft, rockets, satellites, and missiles worldwide. The company also provides leasing and product support s ...
, had acquired the rights to support and produce spare components for the Explorer; however, this deal did not include the ability to perform final assembly or otherwise produce complete rotorcraft. Accordingly, it was speculated that the deal could impact the long-term future of the Explorer. However, these plans were terminated due to the intervention of the US
Federal Trade Commission The Federal Trade Commission (FTC) is an independent agency of the United States government whose principal mission is the enforcement of civil (non-criminal) United States antitrust law, antitrust law and the promotion of consumer protection. It ...
.Frawley 2003, p. 155. Instead, in the following year, Boeing opted to spin off its civilian line of helicopters, including the Explorer, to the newly formed ''MD Helicopter Holdings Inc.'' (MDHI). During November 1999, the JAA recommended that all 27 member nations certify the Explorer series for Category A single pilot IFR operations. In September 2000, the first Explorers had been delivered with the further improved PW207E engine, which provided improved hot and high performance, as well as when flown with only a single engine operational. During the 2000s, the company recovered from its financial woes and invested in the replenishment of its supply chain. In the 2010s, the manufacturer dedicated considerable attention to renewing the avionics of the type, such as the addition of a
glass cockpit A glass cockpit is an aircraft cockpit that features an array of electronic (digital) flight instrument display device, displays, typically large liquid-crystal display, LCD screens, rather than traditional Analog device, analog dials and gauges ...
. During 2013, it was announced that MDHI had selected Universal Avionics’ InSight display system for the MD 902 Explorer, replacing the original
cathode ray tube A cathode-ray tube (CRT) is a vacuum tube containing one or more electron guns, which emit electron beams that are manipulated to display images on a phosphorescent screen. The images may represent electrical waveforms on an oscilloscope, a ...
(CRT) displays; four years later, the company started offering an alternative arrangement with
Genesys Aerosystems Genesys may refer to: * Genesys (company), a customer experience and contact center technology company * ''Genesys'' (RPG), a tabletop role-playing game released by Fantasy Flight Games in 2017 * ''Genesys'' (video game), an educational video gam ...
. In January 2020, the company announced a new partnership with Universal Avionics, effectively switching back to the vendor, under which the latter would provide their fully-digital flight deck avionics for the MD 900/902 Explorer. In October 2015, the
Civil Aviation Authority of New Zealand The Civil Aviation Authority of New Zealand (CAA) ( Māori: ''Te Mana Rererangi Tūmatanui o Aotearoa'') is the government agency tasked with establishing civil aviation safety and security standards in New Zealand. The CAA also monitors adhere ...
(CAANZ) granted type acceptance to the MD 900/902 Explorer series, permitting the restriction-free importing of the type into the country. That same year, the
European Aviation Safety Agency The European Union Aviation Safety Agency (EASA) is an agency of the European Commission with responsibility for civil aviation safety in the European Union. It carries out certification, regulation and standardisation and also performs inve ...
(EASA) approved an increased maximum gross weight of 6,770 pounds for the MD 900/902 Explorer, increasing its maximum payload capacity by 270 pounds; this increase had been already approved by the FAA in March 2013. Reportedly, by 2015, almost 50 percent of all MD 900/902 Explorers produced were being operated in Europe in three areas of the market:
emergency medical services Emergency medical services (EMS), also known as ambulance services, pre-hospital care or paramedic services, are emergency services that provide urgent pre-hospital treatment and stabilisation for serious illness and injuries and transport to d ...
(EMS),
law enforcement Law enforcement is the activity of some members of the government or other social institutions who act in an organized manner to enforce the law by investigating, deterring, rehabilitating, or punishing people who violate the rules and norms gove ...
and military/para-military organizations. The EMS sector has been a deliberately selected focus area for MDHI; during 2011, the firm forecasted that
Middle East The Middle East (term originally coined in English language) is a geopolitical region encompassing the Arabian Peninsula, the Levant, Turkey, Egypt, Iran, and Iraq. The term came into widespread usage by the United Kingdom and western Eur ...
ern operators would require several hundred EMS rotorcraft over the coming years. During March 2015, MDHI announced that it was in the process of redesigning the MD Explorer with a higher level of in-house content with the intention of making it more affordable and thus boost sales. The redesign/modernisation of the MD902 Explorer was subsequently referred to the ''MD969''. By August 2022, while the MD Explorer series was still technically in production, some operators were facing difficulties obtaining some crucial components and the supply chain was reportedly drying up. In response, some vendors were acquiring existing airframes and stripping them for their parts.


Design

The MD Helicopters MD Explorer is a twin engined utility
helicopter A helicopter is a type of rotorcraft in which Lift (force), lift and thrust are supplied by horizontally spinning Helicopter rotor, rotors. This allows the helicopter to VTOL, take off and land vertically, to hover (helicopter), hover, and ...
; it is equipped with a fully-
articulated An articulated vehicle is a vehicle which has a permanent or semi-permanent coupling in its construction. This coupling works as a large pivot joint, allowing it to bend and turn more sharply. There are many kinds, from heavy equipment to buse ...
five-bladed main rotor system as well as bearingless composite flexbeams and rotor hub. The fuselage is composed of
composite material A composite or composite material (also composition material) is a material which is produced from two or more constituent materials. These constituent materials have notably dissimilar chemical or physical properties and are merged to create a ...
s, such as carbonfibre, that are resistant to corrosion even in hostile marine environments, it also incorporates lightning strike protection measures. The tail features similar construction. It is powered by a pair of
Pratt & Whitney Canada Pratt & Whitney Canada (PWC or P&WC) is a Canada-based aircraft engine manufacturer. PWC's headquarters are in Longueuil, Quebec, south of Montreal. It is a division of the larger US-based Pratt & Whitney (P&W), itself a business unit of RTX ...
-built PW200
turboshaft A turboshaft engine is a form of gas turbine that is optimized to produce shaft horsepower rather than jet thrust. In concept, turboshaft engines are very similar to turbojets, with additional turbine expansion to extract heat energy from the ex ...
engines. It can be flown by a single pilot, and carry up to six passengers at a time. A key feature of the MD Explorer is the
NOTAR NOTAR ("no tail rotor") is a helicopter system which avoids the use of a tail rotor. It was developed by MD Helicopters, McDonnell Douglas Helicopter Systems (through their acquisition of Hughes Helicopters). The system uses a fan inside the tail ...
anti-torque system; instead of a traditional tail rotor, a fan exhaust is directed out of slots in the tail boom, thus using the
Coandă effect The Coandă effect ( or ) is the tendency of a jet (fluid), fluid jet to stay attached to a surface of any form. ''Merriam-Webster'' describes it as "the tendency of a jet of fluid emerging from an orifice to follow an adjacent flat or curved s ...
for yaw control. The benefits of NOTAR have reportedly included reduced pilot workload, greatly minimised external noise levels, and significant improvements in safety, particularly when operating in confined areas and from
offshore platform An oil platform (also called an oil rig, offshore platform, oil production platform, etc.) is a large structure with facilities to extract and process petroleum and natural gas that lie in rock formations beneath the seabed. Many oil platforms wi ...
s, along with general performance and controllability enhancements. It is disputed which of the
fenestron A Fenestron (sometimes alternatively referred to as a fantail or a "fan-in-fin" arrangementLeishman 2006, p. 321.) is an enclosed helicopter tail rotor that operates like a ducted fan. The term ''Fenestron'' is a trademark of multinational helic ...
and NOTAR approaches produces less noises. Boeing retains the design rights to the NOTAR technology despite selling the former McDonnell Douglas civil helicopter line to MD Helicopters in early 1999.


Variants

;MD 900 Explorer :Initial Production model, powered by two Pratt & Whitney Canada PW206A (or PW206E or PW207E) turboshaft engines. ;MD 901 Explorer :Civil utility transport model, powered by two Turbomeca Arrius turboshaft engines and tri-angel landing gear. McDonnell Douglas Helicopters announced that this type was available from serial number 127 and upwards. By sale of civil helicopter variants to MD Helicopters the type was not further developed. None ordered. ;MD 902 :Marketing name for an enhanced version with Category A approval and powered by two Pratt & Whitney Canada PW206E or PW207E. Enhanced version has additional engine isolation features and changes to the Integrated Instrument Display System. Older helicopters (except for the first seven built) can be modified to the enhanced version. ;MH-90 Enforcer :Armed version for the
United States Coast Guard The United States Coast Guard (USCG) is the maritime security, search and rescue, and Admiralty law, law enforcement military branch, service branch of the armed forces of the United States. It is one of the country's eight Uniformed services ...
flown by the
Helicopter Interdiction Tactical Squadron The Helicopter Interdiction Tactical Squadron (HITRON) is an Armed helicopter, armed United States Coast Guard helicopter squadron (aviation), squadron specializing in Airborne Use of Force (AUF) and drug-interdiction missions. It is based at Ceci ...
between 1998 and 2000. ;MD 969 Combat Explorer :
Armed helicopter An armed helicopter is a military helicopter equipped with aircraft ordnance. Most commonly, it is used for attacking targets on the ground. Such a helicopter could be either purposely designed for a attack aircraft, ground-attack mission—in w ...
version. ;Swift :A high-speed compound helicopter derived from the MD 969 that was being developed for the US Army’s
Future Attack Reconnaissance Aircraft The Future Attack Reconnaissance Aircraft (FARA) program was initiated by the United States Army in 2018 to develop a successor to the Bell OH-58 Kiowa scout helicopter as part of the Future Vertical Lift program. The OH-58 was retired in 2017 ...
(FARA) program. Excluded from FARA in 2019.


Operators

; *
Federal Police A law enforcement agency (LEA) is any government agency responsible for law enforcement within a specific jurisdiction through the employment and deployment of law enforcement officers and their resources. The most common type of law enforcement ...
; *
Landespolizei ; ) is a term used to refer to the state police of any of the states of Germany. History The of today can trace its origins to the late 19th century, when Germany united into a single country in 1871, under Otto von Bismarck. Various ...
; *
Hungarian Police Hungarian may refer to: * Hungary, a country in Central Europe * Kingdom of Hungary, state of Hungary, existing between 1000 and 1946 * Hungarians/Magyars, ethnic groups in Hungary * Hungarian algorithm, a polynomial time algorithm for solving the ...
; * Heliservices ; *
Luxembourg Air Rescue Luxembourg Air Rescue (LAR) is a private, humanitarian air rescue organisation in Luxembourg, the Greater Region surrounding Luxembourg or worldwide through the operation of its helicopters and air ambulances. /www.etat.lu/memorial/2010/C/Html/1720 ...
* Luxembourg Police ; *
Mexican Navy The Mexican Navy () is one of the components of the Mexican Armed Forces. The Secretariat of the Navy is in charge of administration of the navy. The commander of the navy is the Secretary of the Navy, who is both a cabinet minister and a career ...
** 1st Shipborne Patrol Naval Air Squadron,
Mexican Naval Aviation Mexican Naval Aviation (FAN; ), is the naval air unit of the Mexican Navy. The Mexican Navy is divided into two naval fleets: Pacific Ocean and Gulf of Mexico. History Naval aviation in Mexico dates back to 1918, when a Mexican-made float bipla ...
; *
Essex & Herts Air Ambulance Essex & Herts Air Ambulance Trust (EHAAT) is a charity air ambulance service providing a free, life-saving Helicopter Emergency Medical Service (HEMS) for the critically ill and injured of Essex, Hertfordshire and surrounding areas. The ch ...
*
Wiltshire Police Wiltshire Police, formerly known as Wiltshire Constabulary, is the territorial police force responsible for policing the county of Wiltshire (including the Borough of Swindon) in South West England. The force serves 722,000 people over an area ...
; * Calstar *
Drug Enforcement Administration The Drug Enforcement Administration (DEA) is a Federal law enforcement in the United States, United States federal law enforcement agency under the U.S. Department of Justice tasked with combating illicit Illegal drug trade, drug trafficking a ...
*
National Park Service The National Park Service (NPS) is an List of federal agencies in the United States, agency of the Federal government of the United States, United States federal government, within the US Department of the Interior. The service manages all List ...
* CoxHealth ; * Doctor Heli


Former operator

; *
Cornwall Air Ambulance The Cornwall Air Ambulance Trust is a charity that provides a dedicated helicopter emergency medical service (HEMS) for Cornwall and the Isles of Scilly. The service operates a Leonardo AW169 helicopter and two critical care cars that are u ...
**
London's Air Ambulance London's Air Ambulance Charity is a registered charity that operates a helicopter emergency medical service (HEMS) dedicated to responding to serious trauma emergencies in and around London. Using a helicopter from 08:00 to sunset and rapid re ...
; *
United States Coast Guard The United States Coast Guard (USCG) is the maritime security, search and rescue, and Admiralty law, law enforcement military branch, service branch of the armed forces of the United States. It is one of the country's eight Uniformed services ...
*
Helicopter Interdiction Tactical Squadron The Helicopter Interdiction Tactical Squadron (HITRON) is an Armed helicopter, armed United States Coast Guard helicopter squadron (aviation), squadron specializing in Airborne Use of Force (AUF) and drug-interdiction missions. It is based at Ceci ...
1998-2000


Specifications


See also


References


Citations


Bibliography

* Frawley, Gerard: ''The International Directory of Civil Aircraft, 2003-2004'', Aerospace Publications Pty Ltd, 2003. . * Jackson, Paul. ''Jane's All The World's Aircraft 2003–2004''. Coulsdon, UK: Jane's Information Group, 2003. .


External links


MD Helicopters MD Explorer page

BlueSkyRotor.com- performance datasheet of MD900 Explorer
{{US helicopters 1960s United States helicopters 1960s United States civil utility aircraft
Explorer Exploration is the process of exploring, an activity which has some Expectation (epistemic), expectation of Discovery (observation), discovery. Organised exploration is largely a human activity, but exploratory activity is common to most organis ...
NOTAR helicopters Twin-turbine helicopters Aircraft first flown in 1992