Maintenance, Repair And Overhaul
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Aircraft maintenance is the performance of tasks required to ensure the continuing
airworthiness In aviation, airworthiness is the measure of an aircraft's suitability for Air safety, safe flight. Initial airworthiness is demonstrated by a certificate of airworthiness issued by the civil aviation authority in the state in which the aircraft ...
of an
aircraft An aircraft ( aircraft) is a vehicle that is able to flight, fly by gaining support from the Atmosphere of Earth, air. It counters the force of gravity by using either Buoyancy, static lift or the Lift (force), dynamic lift of an airfoil, or, i ...
or aircraft part, including overhaul, inspection, replacement, defect rectification, and the embodiment of modifications, compliance with airworthiness directives and
repair The technical meaning of maintenance involves functional checks, servicing, repairing or replacing of necessary devices, equipment, machinery, building infrastructure and supporting utilities in industrial, business, and residential installat ...
.


Regulation

The
maintenance The technical meaning of maintenance involves functional checks, servicing, repairing or replacing of necessary devices, equipment, machinery, building infrastructure and supporting utilities in industrial, business, and residential installa ...
of aircraft is highly regulated, in order to ensure safe and correct functioning during flight. In
civil aviation Civil aviation is one of two major categories of flying, representing all non-military and non-state aviation, which can be both private and commercial. Most countries in the world are members of the International Civil Aviation Organization and ...
national regulations are coordinated under international standards, established by the
International Civil Aviation Organization The International Civil Aviation Organization (ICAO ) is a specialized agency of the United Nations that coordinates the principles and techniques of international air navigation, and fosters the planning and development of international sch ...
(ICAO). The ICAO standards have to be implemented by local airworthiness authorities to regulate the maintenance tasks, personnel and inspection system. Maintenance staff must be licensed for the tasks they carry out. Major airworthiness regulatory authorities include the US
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), European Union Aviation Safety Agency (EASA),
Australian Transport Safety Bureau The Australian Transport Safety Bureau (ATSB) is Australia's national transport safety investigator. The ATSB is the federal government body responsible for investigating transport-related accidents and incidents within Australia. It covers ai ...
(ATSB),
Transport Canada Transport Canada () is the Ministry (government department), department within the Government of Canada responsible for developing regulations, Policy, policies and Public services, services of road, rail, marine and air Transport in Canada, tra ...
(TC) and Indian Directorate General of Civil Aviation.


Aircraft maintenance organization


Scheduled maintenance checks

Aircraft maintenance in civil aviation generally organized using a maintenance checks or blocks which are packages of maintenance tasks that have to be done on an aircraft after a certain amount of time or usage. Packages are constructed by dividing the maintenance tasks into convenient, bite-size chunks to minimize the time the aircraft is out of service, to keep the maintenance workload level, and to maximize the use of maintenance facilities.


Pre-emptive engine change

An engine failure can significantly impact operations and revenue. A programme of calculated pre-emptive engine changes, sometimes referred to as "power by the hour", provides budget predictability, avoids installing a loan unit during repairs when an aircraft part fails and enrolled aircraft may have a better value and liquidity. This concept of unscheduled maintenance was initially introduced for aircraft engines to mitigate
engine failure A turbine engine failure occurs when a Gas turbine, gas turbine engine unexpectedly stops producing Power (physics), power due to a malfunction other than fuel exhaustion. It often applies for aircraft, but other turbine engines can also fail, ...
s. The term was coined by Bristol Siddeley in 1962 to support
Viper Vipers are snakes in the family Viperidae, found in most parts of the world, except for Antarctica, Australia, Hawaii, Madagascar, New Zealand, Ireland, and various other isolated islands. They are venomous and have long (relative to non-vipe ...
s of the British Aerospace 125 business jets for a fixed sum per flying hour. A complete engine and accessory replacement service was provided, allowing the operator to accurately forecast this cost, and relieving him from purchasing stocks of engines and accessories. In the 1980s,
Rolls-Royce plc Rolls-Royce Holdings plc is a British multinational aerospace and defence company incorporated in February 2011. The company owns Rolls-Royce, a business established in 1904 which today designs, manufactures and distributes power systems for ...
reinstated the program to provide the operator with a fixed engine maintenance cost over an extended period of time. Operators are assured of an accurate cost projection and avoid the breakdowns costs; the term is trademarked by Rolls-Royce but is the common name in the industry. It is an option for operators of several Rolls-Royce
aircraft engine An aircraft engine, often referred to as an aero engine, is the power component of an aircraft propulsion system. Aircraft using power components are referred to as powered flight. Most aircraft engines are either piston engines or gas turbin ...
s. Other aircraft engine manufacturers such as
General Electric General Electric Company (GE) was an American Multinational corporation, multinational Conglomerate (company), conglomerate founded in 1892, incorporated in the New York (state), state of New York and headquartered in Boston. Over the year ...
and
Pratt & Whitney Pratt & Whitney is an American aerospace manufacturer with global service operations. It is a subsidiary of RTX Corporation (formerly Raytheon Technologies). Pratt & Whitney's aircraft engines are widely used in both civil aviation (especially ...
offer similar programs. Jet Support Services provides hourly cost maintenance programs independently of the manufacturers.
GEMCO The Groote Eylandt Mining Company, known by its acronym GEMCO, is an Australian company that was commissioned to mine high grade manganese ore. GEMCO is majority owned by South32. It runs its operation on 84 square kilometres (32 sq. mi.) of the Ar ...
also offers a similar program for piston engines in general aviation aircraft. Bombardier Aerospace offers its Smart Services program, covering parts and maintenance by the hour.


Maintenance release

At the completion of any maintenance task a person authorized by the national airworthiness authority or delegated organization signs a maintenance release stating that maintenance has been performed in accordance with the applicable airworthiness requirements. A maintenance release is sometimes called a certificate of release to service (CRS). In the case of a certified aircraft this may be a licensed aircraft maintenance engineer, Designated Airworthiness Representative – Maintenance (DAR-T) or holder of an EASA Part-66 Aircraft Maintenance License (AML), while for amateur-built aircraft this may be the owner or builder of the aircraft. In some countries the Secretary of State may authorise a maintenance organization to grant the certification privilege to staff on their behalf.


Maintenance personnel

The
ICAO The International Civil Aviation Organization (ICAO ) is a specialized agency of the United Nations that coordinates the principles and techniques of international air navigation, and fosters the planning and development of international sch ...
defines the licensed or rated role of aircraft maintenance by a technician, engineer or mechanic), allowing that each contracting state may use whichever of these terms it prefers.ICAO; Doc 7300, ''Convention on International Civil Aviation'' (also referred to as the ''Chicago Convention''), 18th Edn. (2018), Annex 1, Chapter 4: Licenses and Ratings for Personnel Other than Flight Crew Members. Although aircraft maintenance technicians, engineers and mechanics all perform essentially the same role, different countries may use these terms in different ways to define their individual levels of qualification and responsibilities. Most national and international licensing bodies make a division between the roles of carrying out repair and maintenance on the one hand, and certifying the vehicle or subsystem or component as flightworthy, on the other. ICAO requires that the certification privilege be a delegated function of the nation's responsible Secretary of State. The Secretary of State may authorize another organization to grant the certification privilege to staff on their behalf. In Europe, licensing is governed by
EASA 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 ...
Part-66. A person directly licensed to certify flightworthiness is a holder of a Part-66 AML (Aircraft Maintenance License). In many other countries, including Australia, Bangla Desh, Canada, India, New Zealand and South Africa, a person directly granted the privilege of certification is a qualified AME ( Aircraft Maintenance Engineer) or Licensed AME, also written as LAME or L-AME. (Unlicensed mechanics or tradespersons are sometimes informally referred to as "Unlicensed AMEs") In the US and elsewhere in the Americas, a person rated for aircraft repair and maintenance is a qualified AMT (
aircraft maintenance technician An aircraft mechanic, aviation mechanic or aircraft maintenance technician (AMT) is a tradesperson who carries out aircraft maintenance and repairs. AMTs inspect and perform or supervise maintenance, repairs and alteration of aircraft and aircr ...
), or, colloquially, Airframe and Powerplant (A&P). A person directly designated to exercise the privilege of certification for the work is a DAR-T (Designated Airworthiness Representative – Maintenance). Roles may be further divided up. In Europe aircraft maintenance personnel must comply with Part 66, Certifying Staff, issued by 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). This regulation establishes four levels of authorization: *Level 1: General Familiarisation, Unlicensed *Level 2: Ramp and Transit, Category A **can only certify own work performed for tasks which he/she has received documented training *Level 3: Line Certifying Staff and Base Maintenance Supporting Staff, Category B1 (electromechanic) and/or B2(Avionics) **can certify all work performed on an aircraft/engine for which he/she is type rated excluding base maintenance (generally up to and including A-Check) *Level 4: Base Maintenance Certifying Staff, Category C **can certify all work performed on an aircraft/engine for which he/she is type rated, but only if it is base maintenance (additional level-3 staff necessary) **this authorization does not automatically include any level 2 or level 3 license.


Market


Aircraft

The maintenance, repair, overhaul (MRO) market was US$135.1 billion in 2015, three quarters of the $180.3 billion aircraft production market. Of this, 60% is for
civil aviation Civil aviation is one of two major categories of flying, representing all non-military and non-state aviation, which can be both private and commercial. Most countries in the world are members of the International Civil Aviation Organization and ...
: air transport 48%, business and
general aviation General aviation (GA) is defined by the International Civil Aviation Organization (ICAO) as all civil aviation aircraft operations except for commercial air transport or aerial work, which is defined as specialized aviation services for other ...
9%,
rotorcraft A rotary-wing aircraft, rotorwing aircraft or rotorcraft is a heavier-than-air aircraft with rotor wing, rotary wings that spin around a vertical mast to generate lift (force), lift. Part 1 (Definitions and Abbreviations) of Subchapter A of Chapt ...
3%; and
military aviation Military aviation is the design, development and use of military aircraft and other flying machines for the purposes of conducting or enabling aerial warfare, including national airlift (air cargo) capacity to provide military logistics, logist ...
is 40%: fixed wing 27% and rotary 13%. Of the $64.3 billion air transport MRO market, 40% is for engines, 22% for components, 17% for line, 14% for airframe and 7% for modifications. It is projected to grow at 4.1% per annum until 2025 to $96 billion. Airliner MRO should reach $74.3 billion in 2017: 51% ($B) single-aisles, 21% ($B) long-range twin-aisles, 8% ($B) medium-range twin-aisles, 7% ($B) large aircraft, 6% ($B)
regional jet A regional jet (RJ) is a jet airliner, jet-powered regional airliner usually defined by having fewer than 100 seats. The first aircraft considered part of this category was the Sud-Aviation Caravelle in 1959, followed by Douglas DC-9, BAC O ...
s as turboprop
regional airliner A regional airliner, commuter airliner or feeder liner is a small airliner that is designed to fly up to 100 passengers on short-haul flights, usually feeding larger carriers' airline hubs from small markets. This class of airliners is typically ...
s and 1% ($B) short range twin-aisles. Over the 2017–2026 decade, the worldwide market should reach over $900 billion, led by 23% in North America, 22% in Western Europe, and 19% in Asia Pacific. In 2017, of the $70 billion spent by airlines on maintenance, repair and overhaul (MRO), 31% were for engines, 27% for components, 24% for line maintenance, 10% for modifications and 8% for the airframe; 70% were for mature airliners (
Airbus A320 The Airbus A320 family is a series of narrow-body airliners developed and produced by Airbus. The A320 was launched in March 1984, Maiden flight, first flew on 22 February 1987, and was introduced in April 1988 by Air France. The first membe ...
and A330,
Boeing 777 The Boeing 777, commonly referred to as the Triple Seven, is an American long-range wide-body airliner developed and manufactured by Boeing Commercial Airplanes. The 777 is the world's largest twinjet and the most-built wide-body airliner. ...
and 737NG), 23% were for “sunset” aircraft (
McDonnell Douglas MD-80 The McDonnell Douglas MD-80 is a series of five-abreast single-aisle airliners developed by McDonnell Douglas. It was produced by the developer company until August 1997 and then by Boeing Commercial Airplanes. The MD-80 was the second gener ...
,
Boeing 737 Classic The Boeing 737 Classic is a series of narrow-body aircraft, narrow-body airliners produced by Boeing Commercial Airplanes, the second generation of the Boeing 737 series of aircraft. Development began in 1979 and the first variant, the 737-300 ...
,
747 747 may refer to: * 747 (number), a composite number * AD 747, a year of the Julian calendar * 747 BC, a year in the 8th century BC * Boeing 747, a large commercial plane Arts and media * 747s (band), an indie band * ''747'' (album), by country m ...
or
757 757 may refer to:575 * Boeing 757, a narrow-body airliner * AD 757, a year * 757 BC, a year * 757 (number), a number * Area code 757, a North American telephone dialling code * "757", a song by 100 gecs from ''10,000 gecs'' * The 757, a nickname fo ...
) and 7% was spent on modern models (
Boeing 787 The Boeing 787 Dreamliner is an American wide-body airliner developed and manufactured by Boeing Commercial Airplanes. After dropping its unconventional Sonic Cruiser project, Boeing announced the conventional 7E7 on January 29, 2003, wh ...
,
Embraer E-Jet The Embraer E-Jet family is a series of four-abreast, narrow-body, short- to medium-range, twin-engined jet airliners designed and produced by Brazilian aerospace manufacturer Embraer. The E-Jet was designed to complement Embraer’s earlier ...
, Airbus A350XWB and A380). In 2018, the commercial aviation industry expended $88 billion for MRO, while military aircraft required $79.6 billion, including field maintenance. Airliner MRO is forecast to reach $115 billion by 2028, a 4%
compound annual growth rate Compound annual growth rate (CAGR) is a business, economics and investing term representing the mean annualized growth rate for compounding values over a given time period. CAGR smoothes the effect of volatility of periodic values that can render ...
from $77.4 billion in 2018. Major airframe manufacturers
Airbus Airbus SE ( ; ; ; ) is a Pan-European aerospace corporation. The company's primary business is the design and manufacturing of commercial aircraft but it also has separate Airbus Defence and Space, defence and space and Airbus Helicopters, he ...
,
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 ...
and
Embraer Embraer S.A. () is a Brazilian multinational aerospace corporation. It develops and manufactures aircraft and aviation systems, and provides leasing, equipment, and technical support services. Embraer is the third largest producer of civil air ...
entered the market, increasing concerns about
intellectual property Intellectual property (IP) is a category of property that includes intangible creations of the human intellect. There are many types of intellectual property, and some countries recognize more than others. The best-known types are patents, co ...
sharing. Shared data-supported
predictive maintenance Predictive maintenance techniques are designed to help determine the condition of in-service equipment in order to estimate when maintenance should be performed. This approach claims more cost savings over routine or time-based preventive maint ...
can reduce operational disruptions. Among other factors, prognostics helped
Delta Air Lines Delta Air Lines, Inc. is a Major airlines of the United States, major airline in the United States headquartered in Atlanta, Georgia (U.S. state), Georgia, operating nine hubs, with Hartsfield–Jackson Atlanta International Airport being its ...
reduce maintenance cancellations by 98% from 5,600 in 2010 to 78 in 2017. Insourced maintenance can be inefficient for small airlines with a fleet below 50–60 aircraft. They have to either
outsource Outsourcing is a business practice in which company, companies use external providers to carry out business processes that would otherwise be handled internally. Outsourcing sometimes involves transferring employees and assets from one firm to ...
it or sell its MRO services to other carriers for better resource utilization. For example, Spain's
Air Nostrum Air Nostrum (doing business as Iberia Regional) is a Spanish regional airline based in Valencia that merged with CityJet in 2023, forming the region's largest aviation holding company, Strategic Alliance of Regional Airlines (SARA). An affiliate ...
operates 45
Bombardier CRJ The Bombardier CRJ/Mitsubishi CRJ or CRJ Series (for Canadair Regional Jet) is a family of regional jets introduced in 1991 by Bombardier Aerospace. The CRJ was manufactured by Bombardier Aerospace with the manufacturing of the first CRJ gene ...
s and
ATR 72 The ATR 72 is a twin-engine turboprop, short-haul regional airliner developed and produced in France and Italy by aircraft manufacturer ATR. The number "72" in its name is derived from the aircraft's typical standard seating capacity of 72 pa ...
s and its 300-person maintenance department provides line, base maintenance and limited component repair for other airlines 20% of the time.
Airframe The mechanical structure of an aircraft is known as the airframe. This structure is typically considered to include the fuselage, undercarriage, empennage and wings, and excludes the propulsion system. Airframe design is a field of aeros ...
heavy maintenance is worth $6 billion in 2019: $2.9 billion for C checks and $3.1 billion for
D check Aircraft maintenance checks are periodic inspections that have to be done on all commercial and civil aircraft after a certain amount of time or usage. Military aircraft normally follow specific maintenance programmes which may, or may not, be si ...
s, ''
Aviation Week & Space Technology ''Aviation Week & Space Technology'', often abbreviated ''Aviation Week'' or ''AW&ST'', is the flagship magazine of the Aviation Week Network, a division of Informa. The weekly magazine is available in print and online, reporting on the aeros ...
'' forecasts a growth to $7.5 billion in 2028 — $3.1 billion C and $4.2 billion D — for $70 billion over 10 years, 10% of the overall market compared to 40% for the engines.


Engines

The commercial aviation engine MRO market is anticipated by ''
Aviation Week & Space Technology ''Aviation Week & Space Technology'', often abbreviated ''Aviation Week'' or ''AW&ST'', is the flagship magazine of the Aviation Week Network, a division of Informa. The weekly magazine is available in print and online, reporting on the aeros ...
'' to be $25.9 billion in 2018, a 2.5 billion increase from 2017, led by 21% for the
Boeing 737NG The Boeing 737 Next Generation, commonly abbreviated as 737NG, or 737 Next Gen, is a twin-engine narrow-body aircraft produced by Boeing Commercial Airplanes. Launched in 1993 as the third-generation derivative of the Boeing 737, it has been ...
' CFM56-7B and the A320's CFM56-5B and IAE V2500 (also on the MD-90) tied for second, followed by the mature widebody engines: the GE90 then the Trent 700. Over the 2017–2026 decade, the largest markets for
turbofan A turbofan or fanjet is a type of airbreathing jet engine that is widely used in aircraft engine, aircraft propulsion. The word "turbofan" is a combination of references to the preceding generation engine technology of the turbojet and the add ...
s will be the B737NG's CFM56-7 with 23%, the
V2500 The IAE V2500 is a two-shaft high-bypass turbofan engine built by International Aero Engines (IAE) which powers the Airbus A320 family, the McDonnell Douglas MD-90, and the Embraer C-390 Millennium. The engine's name is a combination of the ...
-A5 with 21%, the
General Electric GE90 The General Electric GE90 is a family of High-bypass turbofan engine, high-bypass turbofan aircraft engines built by GE Aerospace for the Boeing 777, with thrust ratings from . It entered service with British Airways in November 1995. It is one ...
-115B with 13%, the A320's CFM56-5B with 13%, the
PW1000G The Pratt & Whitney PW1000G family, also marketed as the Pratt & Whitney GTF (geared turbofan), is a family of high-bypass geared turbofan engines produced by Pratt & Whitney. The various models can generate 15,000 to 33,000 Pound (force), pounds ...
with 7%, the
Rolls-Royce Trent 700 The Rolls-Royce Trent 700 is a high-bypass turbofan aircraft engine produced by Rolls-Royce plc to power the Airbus A330. Rolls-Royce was studying a RB211 development for the A330 at its launch in June 1987. It was first selected by Cathay P ...
with 6%, the
CF6 The General Electric CF6, US military designations F103 and F138, is a family of high-bypass turbofan engines produced by GE Aviation. Based on the TF39, the first high-power high-bypass jet engine, the CF6 powers a wide variety of civilian a ...
-80C2 with 5%, the
CFM LEAP The CFM International LEAP ("Leading Edge Aviation Propulsion") is a high-bypass turbofan engine produced by CFM International, a 50–50 joint venture between the American GE Aerospace and the French Safran Aircraft Engines. As the successor ...
with 5% and the
General Electric CF34 The General Electric CF34 is a civilian high-bypass turbofan developed by GE Aviation from its TF34 military engine. The CF34 is used on a number of business and regional jets, including the Bombardier CRJ series, the Embraer E-Jets, and ...
-8 with 4%. Between 2018 and 2022, the largest MRO demand will be for CFM engines with 36%, followed by GE with 24%, Rolls with 13%, IAE with 12% and Pratt with 7%. As an aircraft gets older, a greater percentage of its value is represented by its
engine An engine or motor is a machine designed to convert one or more forms of energy into mechanical energy. Available energy sources include potential energy (e.g. energy of the Earth's gravitational field as exploited in hydroelectric power ge ...
s. Over the course of the engine life it is possible to put value back in by repair and overhaul, to sell it for its remaining useful time, or to disassemble it and sell the used parts, to extract its remaining value. Its maintenance value includes the value of life-limited parts (LLPs) and the time before overhaul. The core value is the value of its data plate and non-life-limited-parts. Engine makers deeply discount their sales, up to 90%, to win the multi-year stream of spares and services, resembling the
razor and blades model The razor and blades business model is a business model in which one item is sold at a low price (or given away) in order to increase sales of a complementary good, such as consumable supplies. It is different from loss leader marketing and pro ...
. Engines installed on a new aircraft are discounted by at least 40% while spare engine values closely follow list prices. Accounting for 80% of a shop visit cost, prices escalate to recoup the original discount, until engine availability increase with aircraft teardowns. Between 2001 and 2018 for the Airbus A320 or the Boeing 737-800, their CFM56 value increased from 27–29% to 48–52% of the aircraft value. The 777-200ER's
Pratt & Whitney PW4000 The Pratt & Whitney PW4000 is a family of dual-spool, axial-flow, high-bypass turbofan aircraft engines produced by Pratt & Whitney as the successor to the JT9D. It was first run in April 1984, was FAA certified in July 1986, and was introduce ...
and the A330-300's
Rolls-Royce Trent 700 The Rolls-Royce Trent 700 is a high-bypass turbofan aircraft engine produced by Rolls-Royce plc to power the Airbus A330. Rolls-Royce was studying a RB211 development for the A330 at its launch in June 1987. It was first selected by Cathay P ...
engines rose from a share of 18–25% in 2001 to 29–40% in 2013. For the
Airbus A320neo The Airbus A320neo family is an incremental development of the A320 family of narrow-body airliners produced by Airbus. The A320neo family (''neo'' being Greek for "new", as well as an acronym for "new engine option") is based on the Airbus A3 ...
and
Boeing 737 MAX The Boeing 737 MAX is a series of narrow-body aircraft developed by Boeing Commercial Airplanes as the fourth generation of the Boeing 737. It succeeds the Boeing 737 Next Generation and incorporates more efficient CFM International LEAP engin ...
, between 52% and 57% of their value lies in their engines: this could rise to 80–90% after ten years, while new
Airbus A350 The Airbus A350 is a flight length, long-range, wide-body twin-engine airliner developed and produced by Airbus. The initial A350 design proposed in 2004, in response to the Boeing 787 Dreamliner, would have been a development of the Airbu ...
or
Boeing 787 The Boeing 787 Dreamliner is an American wide-body airliner developed and manufactured by Boeing Commercial Airplanes. After dropping its unconventional Sonic Cruiser project, Boeing announced the conventional 7E7 on January 29, 2003, wh ...
engines are worth 36–40% of the aircraft. After some time the maintenance reserves exceed the
aircraft lease Aircraft leases are leases used by airlines and other aircraft operators. Airlines lease aircraft from other airlines or leasing companies for two main reasons: to operate aircraft without the financial burden of buying them, as well as to provide ...
. Between 2019 and 2038, 5,200 spare airliner engines will be required with at least half leased.


See also

*
Groundcrew In all forms of aviation, ground crew (also known as ground operations in civilian aviation) are personnel that service aircraft while on the ground, during routine turn-around; as opposed to aircrew, who operate all aspects of an aircraft whi ...
*
Line-replaceable unit A line-replaceable unit (LRU), lower line-replaceable unit (LLRU), line-replaceable component (LRC), or line-replaceable item (LRI) is a modular component of an airplane, ship or spacecraft (or any other manufactured device) that is designed to b ...
* Maintenance Resource Management *
Professional Aviation Maintenance Association The Professional Aviation Maintenance Association (PAMA) is a professional organization for aviation maintenance technicians. History On August 19, 1972, PAMA held its first annual convention in Pittsburgh, Pennsylvania. William Collister was ...
*
RAMS In engineering, reliability, availability, maintainability and safety (RAMS)Shop-replaceable unit A shop-replaceable unit (SRU) or shop-replaceable component (SRC) is a modular component of an airplane, ship or spacecraft that is designed to be replaced by a technician at a backshop. Repair at backshops is known as field-level maintenance or ...


References


External links

* * * * * {{Authority control Aerospace engineering Aircraft engines Aircraft finance Maintenance