View source for Finance:Aircraft maintenance

{{Short description|Performance of tasks which maintain an aircraft's airworthiness}}
[[File:Airbus A321-211Iberia EC-IGK (5567789129).jpg|thumb|An [[Engineering:Airbus A321|Airbus A321]] from Iberia having its CFM56 changed]]

'''Aircraft maintenance''' is the performance of tasks required to ensure the continuing airworthiness of an [[Engineering:Aircraft|aircraft]] or [[Engineering:Aircraft part|aircraft part]], including overhaul, inspection, replacement, defect rectification, and the embodiment of modifications, compliance with airworthiness directives and repair.<ref name="CAR101">{{cite web|url=http://www.tc.gc.ca/eng/civilaviation/regserv/cars/part1-subpart1-1104.htm |title=Canadian Aviation Regulations 2008-1, Part I - General Provisions, Subpart 1 - Interpretation |access-date=9 December 2012 |last=Transport Canada |date=May 2012 |url-status=dead |archive-url=https://web.archive.org/web/20121227092905/http://www.tc.gc.ca/eng/civilaviation/regserv/cars/part1-subpart1-1104.htm |archive-date=27 December 2012 }}</ref><ref name="CAR593">{{cite web|url=http://www.tc.gc.ca/eng/civilaviation/regserv/cars/part5-standards-593s-1829.htm |title=Canadian Aviation Regulations 2008-1, Part V - Airworthiness, Standard 593 - Airworthiness Directives |access-date=9 December 2012 |last=Transport Canada |author-link=Transport Canada |date=March 2002 |url-status=dead |archive-url=https://web.archive.org/web/20130518090436/http://www.tc.gc.ca/eng/civilaviation/regserv/cars/part5-standards-593s-1829.htm |archive-date=18 May 2013 }}</ref>

==Regulation==
The maintenance of aircraft is highly regulated, in order to ensure safe and correct functioning during flight. In civil aviation national regulations are coordinated under international standards, established by the International Civil Aviation Organization (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.<ref name=AWM/>

Major airworthiness regulatory authorities include the US Federal Aviation Administration (FAA), European Union Aviation Safety Agency (EASA), Australian Transport Safety Bureau (ATSB), Transport Canada (TC) and Indian Directorate General of Civil Aviation.

==Aircraft maintenance organization==
[[File:Bombardier Maintenance (6240614231).jpg|thumb|Technicians work on a Bombardier airplane in Dallas, Texas]]

=== Scheduled maintenance checks===
{{Main|Engineering:Aircraft 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.<ref>{{Cite web|last= Hessburg|first=Jack|title=What's This 'A' Check, 'C' Check Stuff?|url=https://www.aviationpros.com/aircraft/article/10388655/whats-this-a-check-c-check-stuff|access-date=2020-12-23|website=www.aviationpros.com|date=April 2000 }}</ref>

===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 failures.<ref>{{cite news |url= http://aviationweek.com/business-aviation/how-hourly-maintenance-provides-shelter-explosive-surprises |title= How Hourly Maintenance Provides Shelter From Explosive Surprises |date= Nov 3, 2017 |author= William Garvey |work= Aviation Week & Space Technology}}</ref> The term was coined by Bristol Siddeley in 1962 to support Vipers of the [[Engineering:British Aerospace 125|British Aerospace 125]] business jets for a fixed sum per flying hour.<ref>{{cite press release |url= https://www.rolls-royce.com/media/press-releases/yr-2012/121030-the-hour.aspx |title= Rolls-Royce celebrates 50th anniversary of Power-by-the-Hour |date= 30 October 2012 |publisher= Rolls-Royce}}</ref> 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.{{Citation needed|date=December 2020}}

In the 1980s, Rolls-Royce plc 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.<ref>{{cite web |title= 'Power by the Hour': Can Paying Only for Performance Redefine How Products Are Sold and Serviced? |url= http://knowledge.wharton.upenn.edu/article.cfm?articleid=1665 |work= Knowledge at Wharton |date= Feb 21, 2007}}</ref> It is an option for operators of several Rolls-Royce [[Engineering:Aircraft engine|aircraft engine]]s.{{Citation needed|date=December 2017}} Other aircraft engine manufacturers such as [[Company:General Electric|General Electric]] and Pratt & Whitney offer similar programs.<ref>{{cite web |last1=GE Aviation |title=GE Engine Services Introduces CF34 Maintenance Cost Per Hour Program |url=https://www.geaviation.com/press-release/services/ge-engine-services-introduces-cf34-maintenance-cost-hour-program |access-date=27 June 2022}}</ref><ref>{{cite web |last1=Pratt & Whitney |title=ESP™ Maintenance Program |url=https://www.pwc.ca/en/products-and-services/services/maintenance-programs-and-solutions/maintenance-programs/esp-maintenance-program |access-date=27 June 2022}}</ref>

Jet Support Services provides hourly cost maintenance programs independently of the manufacturers.<ref>{{cite web |title= Jet Support Services, Inc. |url= http://investing.businessweek.com/businessweek/research/stocks/private/snapshot.asp?privcapId=4663513 |archive-url= https://archive.today/20120720160138/http://investing.businessweek.com/businessweek/research/stocks/private/snapshot.asp?privcapId=4663513 |url-status= dead |archive-date= July 20, 2012 |publisher= Bloomberg Businessweek }}</ref> GEMCO also offers a similar program for piston engines in general aviation aircraft.{{Citation needed|date=December 2017}} Bombardier Aerospace offers its ''Smart Services'' program, covering parts and maintenance by the hour.{{Citation needed|date=December 2017}}

===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).<ref name=AWM>{{cite book |title=Airworthiness Manual, Doc 9760 |url=https://store.icao.int/airworthiness-manual-english-printed.html |edition=3 |location=Montreal (Canada) |publisher=International Civil Aviation Organization |date=2014 |pages= |isbn=978-92-9249-454-4 |access-date=2018-09-01 |archive-url=https://web.archive.org/web/20180901145432/https://store.icao.int/airworthiness-manual-english-printed.html |archive-date=2018-09-01 |url-status=dead }}</ref>

In the case of a [[Engineering:Type certificate|certified aircraft]] this may be a licensed [[Engineering:Aircraft Maintenance Engineer|Aircraft Maintenance Engineer]], Designated Airworthiness Representative – Maintenance (DAR-T) or holder of an EASA Part-66 Aircraft Maintenance License (AML), while for [[Engineering:Homebuilt aircraft|amateur-built aircraft]] this may be the owner or builder of the aircraft.<ref name="CAR571.10">{{cite web |url= https://www.tc.gc.ca/eng/civilaviation/regserv/cars/part5-standards-571s-1827.htm |title= Canadian Aviation Regulations (CARs)Part V - Standard 571 - Maintenance |at= 571.10 Maintenance Release |publisher= Transport Canada |date= 2010-12-01 }}</ref>

In some countries The Secretary of State may authorise a maintenance organization to grant the certification privilege to staff on their behalf.

== Maintenance personnel==
[[File:Field maintenance on a 1956 model Cessna 172.JPG|thumb|Field maintenance on a [[Engineering:Cessna 172|Cessna 172]] being conducted from a van used to carry tools and parts]]

The ICAO 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.<ref name="icao4">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.</ref> 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.{{Citation needed|date=December 2020}}

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.<ref name="icao4"/>

In Europe, licensing is governed by EASA Part-66. A person directly licensed to certify flightworthiness is a holder of a Part-66 AML (Aircraft Maintenance License).<ref>[https://www.caa.co.uk/commercial-industry/aircraft/airworthiness/engineer-licences/part-66/ Part-66]<, CAA, 2022. (retrieved 5 August 2022)</ref>

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 ([[Engineering:Aircraft Maintenance Engineer|Aircraft Maintenance Engineer]]) or Licensed AME, also written as LAME or L-AME.<ref>[https://tc.canada.ca/en/aviation/licensing-aircraft-maintenance-engineers-ame Licensing for aircraft maintenance engineers (AME)], Transport Canada, 2022.</ref> (Unlicensed mechanics or tradespersons are sometimes informally referred to as "Unlicensed AMEs"<ref>[https://www.sunsea-aviation.com/aircraft-maintenance-engineering-ame/ Aircraft Maintenance Engineering], Sunsea Aviation Services Ltd. (retrieved 5 August 2022)</ref>)

In the US and elsewhere in the Americas, a person rated for aircraft repair and maintenance is a qualified AMT (Aircraft Maintenance Technician), or colloquially Airframe and Powerplant (A&P).<ref>[https://www.faa.gov/mechanics/become Become an Aviation Mechanic], FAA, 2022. (retrieved 5 August 2022)</ref> A person directly designated to exercise the privilege of certification for the work is a DAR-T (Designated Airworthiness Representative – Maintenance).<ref>[https://www.faa.gov/other_visit/aviation_industry/designees_delegations/ Designees], Federal Aviation Administration, 2021.</ref>

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 (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==
[[File:Luftwaffe GR-4 Tornado undergoing maintenance during Cooperative Cope Thunder 2004.JPEG|thumb|A [[Engineering:Panavia Tornado|Panavia Tornado]] undergoing maintenance]]

===Aircraft===
The Maintenance, Repair, Overhaul (MRO) Market was US$135.1 billion in 2015, three quarters of the $180.3 B aircraft production market. Of this, 60% is for civil aviation: air transport 48%, business and general aviation 9%, [[Engineering:Rotorcraft|rotorcraft]] 3%; and military aviation 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 $96B.<ref>{{cite web |url= https://www.aeromontreal.ca/download/fca8adddfff353/01-MRO+Industry+Outlook_Kevin+Michaels.pdf |title= MRO Industry Outlook |author= Kevin Michaels |publisher= ICF International |date= April 28, 2016}}</ref>

Airliner MRO should reach $74.3 billion in 2017: 51% (${{#expr:74.3*.51round1}}B) single-aisles, 21% (${{#expr:74.3*.21round1}}B) long-range [[Engineering:Twin-aisle|twin-aisle]]s, 8% (${{#expr:74.3*.08round1}}B) medium-range twin-aisles, 7% (${{#expr:74.3*.07round1}}B) [[Engineering:Large aircraft|large aircraft]], 6% (${{#expr:74.3*.06round1}}B) [[Engineering:Regional jet|regional jet]]s as turboprop [[Engineering:Regional airliner|regional airliner]]s and 1% (${{#expr:74.3*.01round1}}B) short range twin-aisles.<ref>{{cite news |url= http://www.mro-network.com/maintenance-repair-overhaul/2017-mro-market-share-category |title= 2017 MRO Market Share by Category |date= July 12, 2017 |work= Aviation Week Network}}</ref>

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.<ref name="MRO16aug2017">{{cite news |url= http://www.mro-network.com/maintenance-repair-overhaul/top-10-engine-mro-demand-2017-26 |title= Top 10 Engine MRO Demand: 2017–26 |date= August 16, 2017 |work= Aviation Week Network}}</ref>

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 ([[Engineering:Airbus A320|Airbus A320]] and [[Engineering:Airbus A330|A330]], [[Engineering:Boeing 777|Boeing 777]] and [[Engineering:Boeing 737 Next Generation|737NG]]), 23% were for “sunset” aircraft ([[Engineering:McDonnell Douglas MD-80|McDonnell Douglas MD-80]], [[Engineering:Boeing 737 Classic|Boeing 737 Classic]], [[Engineering:Boeing 747|747]] or [[Engineering:Boeing 757|757]]) and 7% was spent on modern models (Boeing 787, Embraer E-Jet, Airbus A350XWB and [[Engineering:Airbus A380|A380]]).<ref>{{cite news |url= http://aviationweek.com/commercial-aviation/opinion-oems-focus-mature-aircraft-aftermarket-growth |title= Opinion: OEMs Focus On Mature Aircraft For Aftermarket Growth |date= January 16, 2018 |author= Kevin Michaels |work= Aviation Week & Space Technology}}</ref>

In 2018, the commercial aviation industry expended $88 billion for MRO, while military aircraft required $79.6 billion, including field maintenance.<ref>{{cite news |url= http://aviationweek.com/commercial-aviation/commercial-spending-will-lead-mro-field-2018 |title= Commercial Spending Will Lead MRO Field In 2018 |at= Comparing civil, helicopter, business aviation and military MRO forecasts for 2018 |date= January 2, 2018 |author= Lee Ann Shay |work= Aviation Week & Space Technology}}</ref>

Airliner MRO is forecast to reach $115 billion by 2028, a 4% [[Compound annual growth rate|compound annual growth rate]] from $77.4 billion in 2018.<ref>{{cite news |url= https://www.flightglobal.com/news/articles/global-mro-spend-to-reach-115-billion-by-2028-wym-445243/ |title= Global MRO spend to reach $115 billion by 2028 - Wyman |date= January 26, 2018 |author= Aaron Chong |work=FlightGlobal}}</ref>

Major airframe manufacturers [[Company:Airbus|Airbus]], [[Company:Boeing|Boeing]] and [[Company:Embraer|Embraer]] entered the market, increasing concerns about [[Social:Intellectual property|intellectual property]] sharing. Shared data-supported [[Engineering:Predictive maintenance|predictive maintenance]] can reduce operational disruptions. Among other factors, prognostics helped [[Company:Delta Air Lines|Delta Air Lines]] reduce maintenance cancellations by 98% from 5,600 in 2010 to 78 in 2017.<ref>{{cite news |url=https://www.flightglobal.com/news/articles/analysis-airframers-set-out-on-differing-aftermarke-448014/ |title= Airframers set out on differing aftermarket paths |date= April 25, 2018 |author= Jon Hemmerdinger |work= FlightGlobal}}</ref>

[[Finance:Insourcing|Insourced]] maintenance can be inefficient for small airlines with a fleet below 50–60 aircraft.<!--<ref name=MRO12mar2018>--> They have to either outsource it or sell its MRO services to other carriers for better resource utilization.<!--<ref name=MRO12mar2018>-->

For example, Spain's Air Nostrum operates 45 Bombardier CRJs and [[Engineering:ATR 72|ATR 72]]s and its 300-person maintenance department provides line, base maintenance and limited component repair for other airlines 20% of the time.<ref name="MRO12mar2018">{{cite news |url= http://www.mro-network.com/airlines/outsourcing-versus-sourcing-small-fleets |title= Outsourcing Versus In-Sourcing For Small Fleets |author= Henry Canaday |date= March 12, 2018 |work= Aviation Week Network - MRO}}</ref>

[[Engineering:Airframe|Airframe]] heavy maintenance is worth $6 billion in 2019: $2.9 billion for C checks and $3.1 billion for D checks, ''Aviation Week & Space Technology'' 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.<ref>{{cite news |url= http://aviationweek.com/commercial-aviation/2019-outlook-airframe-heavy-maintenance |title= 2019 Outlook For Airframe Heavy Maintenance |date= December 18, 2018 |author= Alex Derber |work= Aviation Week & Space Technology}}</ref>

===Engines===
[[File:Visual inspection of compressor blades-090108-F-9919G-746.jpg|thumb|US Air force technicians disassemble and inspects the CFM56 fan blades of a KC-135, inspected every 1,500 hours.]]

The commercial aviation engine MRO market is anticipated by ''Aviation Week & Space Technology'' to be $25.9 billion in 2018, a 2.5 billion increase from 2017, led by 21% for the Boeing 737NG' 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.<ref>{{cite news |url= http://www.mro-network.com/maintenance-repair-overhaul/life-old-dogs-yet |title= Life In The Old Dogs Yet |author=James Pozzi |date= Nov 24, 2017 |work= Aviation Week Network}}</ref>

Over the 2017–2026 decade, the largest markets for [[Engineering:Turbofan|turbofan]]s will be the B737NG's CFM56-7 with 23%, the V2500-A5 with 21%, the [[Engineering:General Electric GE90|General Electric GE90]]-115B with 13%, the A320's CFM56-5B with 13%, the PW1000G with 7%, the [[Engineering:Rolls-Royce Trent 700|Rolls-Royce Trent 700]] with 6%, the CF6-80C2 with 5%, the CFM LEAP with 5% and the [[Engineering:General Electric CF34|General Electric CF34]]-8 with 4%.<ref name=MRO16aug2017/>
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%.<ref>{{cite news |url= http://www.mro-network.com/engines-engine-systems/engine-mro-demand-top-5-engine-oem-2018-22 |title= Engine MRO Demand - Top 5 Engine OEM: 2018–22 |date= May 30, 2018 |work= MRO Network |publisher= Aviation Week Network}}</ref>

As an aircraft gets older, a greater percentage of its value is represented by its [[Engineering:Aircraft engine|engine]]s.<!--<ref name=MRO16oct2017>-->
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.<!--<ref name=MRO16oct2017>-->
Its maintenance value includes the value of [[Engineering:Aircraft part#Life limited parts|life-limited parts]] (LLPs) and the time before overhaul.<!--<ref name=MRO16oct2017>-->
The core value is the value of its data plate and non-life-limited-parts.<ref name=MRO16oct2017>{{cite news |url= http://www.mro-network.com/maintenance-repair-overhaul/keeping-eye-engine-values |title= Keeping An Eye On Engine Values |author= Alex Derber |date= Oct 16, 2017 |work= Aviation Week network}}</ref>
Engine makers deeply [[Finance:Discounts and allowances|discount]] their sales, up to 90%, to win the multi-year stream of spares and services, resembling the [[Finance:Razor and blades model|razor and blades model]].<ref>{{cite news |url= https://www.airinsight.com/the-meaningless-game-of-list-prices/ |title= The Meaningless Game of List Prices |date= January 19, 2018 |author= Ernest S. Arvai |work= AirInsight}}</ref>

Engines installed on a new aircraft are discounted by at least 40% while [[Finance:Spare part|spare]] engine values closely follow list prices.<!--<ref name=Flight21jun2018>-->
Accounting for 80% of a shop visit cost, {{abbr|LLP|life-limited part}} prices escalate to recoup the original discount, until engine availability increase with [[Engineering:Aircraft recycling|aircraft teardown]]s.<!--<ref name=Flight21jun2018>-->
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.<!--<ref name=Flight21jun2018>-->
The 777-200ER's Pratt & Whitney PW4000 and the A330-300's [[Engineering:Rolls-Royce Trent 700|Rolls-Royce Trent 700]] engines rose from a share of 18–25% in 2001 to 29–40% in 2013.<!--<ref name=Flight21jun2018>-->
For the Airbus A320neo and [[Engineering:Boeing 737 MAX|Boeing 737 MAX]], between 52% and 57% of their value lies in their engines: this could rise to 80–90% after ten years, while new [[Engineering:Airbus A350|Airbus A350]] or Boeing 787 engines are worth 36–40% of the aircraft.<!--<ref name=Flight21jun2018>-->
After some time the maintenance reserves exceed the [[Finance:Aircraft lease|aircraft lease]].<ref name=Flight21jun2018>{{cite news |url= https://www.flightglobal.com/news/articles/analysis-the-influence-of-engines-on-aircraft-value-449410/ |title= Analysis: The influence of engines on aircraft values |date= 21 June 2018 |author= David Griffin |work= FlightGlobal}}</ref>

Between 2019 and 2038, 5,200 spare airliner engines will be required with at least half leased.<ref>{{cite news |url= https://www.mro-network.com/leasing-financial-services/engine-leasing-rude-health |title= Engine Leasing In Rude Health |author= Alex Derber |date= Oct 22, 2018 |work= Aviation Week Intelligence Network}}</ref>

[[File:AFI 05 2017 Donecle drone 002.jpg|thumb|right|Autonomous [[Company:Donecle|Donecle]] UAV performing an aircraft inspection.]]

== See also ==
* Airworthiness
* Groundcrew
* [[Engineering:Line-replaceable unit|Line-replaceable unit]]
* Maintenance Resource Management
* [[Engineering:Maintenance (technical)|Maintenance (technical)]]
* Professional Aviation Maintenance Association
* [[Engineering:RAMS|RAMS]]
* [[Engineering:Shop-replaceable unit|Shop-replaceable unit]]

==References==
{{Reflist}}

==External links==
* {{cite news |url= http://www.mro-network.com/airlines/day-americans-line-operations-chicago-ohare |title= A Day In American's Line Operations At Chicago O'Hare |author= Lindsay Bjerregaard, Lee Ann Shay |date= Oct 11, 2017 |work= Aviation Week network}}
* {{cite news |url= http://www.mro-network.com/maintenance-repair-overhaul/inside-iberia-s-engine-shop |title= Inside Iberia's Engine Shop |author= James Pozzi |date= Oct 17, 2017 |work= Aviation Week network}}
* {{cite news |url= http://www.mro-network.com/maintenance-repair-overhaul/look-around-lufthansa-technik-sofias-expanded-facility/gallery?slide=1 |title= A Look Around Lufthansa Technik Sofia's Expanded Facility |author= James Pozzi |date= Nov 4, 2017 |work= Aviation Week network}}
* {{cite news |url= http://www.mro-network.com/hangars-equipment/ground-jetblue-s-jfk-hangar |title= On The Ground At JetBlue's JFK Hangar |author= Lindsay Bjerregaard |date= Nov 13, 2017 |work= Aviation Week network}}
* {{cite video |url= https://www.youtube.com/playlist?list=PLSlru5PbHgUH8AMT4PB48nlHXHqNME7TC |title= Maintenance Minute |author= GE Aviation |quote= Maintenance Minute videos are produced by GE Aviation's training team to help the aircraft maintainer with everyday engine maintenance tasks.}}


[[Category:Aircraft maintenance| ]]
[[Category:Aerospace engineering]]
[[Category:Aircraft engines]]
[[Category:Aircraft finance]]

{{Sourceattribution|Aircraft maintenance}}