{{Short description|Paris Metro train}} <!-- Note: The following pages were redirects to MF 88 before draftification: *Boa (Paris Métro) *MF88 --> {{Expand French|MF 88|date=September 2020|topic=transport}} {{Infobox EMU | background = #8FD5BB | name = MF 88 | image = MF 88 at Pré Saint-Gervais Station, Paris 19e 20140427.jpg | imagesize = 300px | caption = MF 88 trainset at Pré-Saint-Gervais station on Line 7bis. | interiorimage = Interieur MF88.jpg | interiorcaption = Interior of MF 88 trainset | stocktype = | service = 1993–present | manufacturer = GEC Alsthom, Faiveley, Renault, ANF | replaced = Sprague-Thomson | constructed = 1990–1992 | yearscrapped = 2013 | numberbuilt = 27 cars (9 trainsets) | numberscrapped = 3 cars (1 trainset) | successor = MF 19 | formation = 3 cars per trainset | capacity = 425 people per trainset | operator = RATP | lines = {{rint|paris|m}}{{nnbsp}}{{rint|paris|m|7bis}} | trainlength = {{cvt|45.44|m|ftin}} | carlength = {{cvt|15.15|m|ftin}} | maxspeed = {{Unbulleted list | Design: {{cvt|80|km/h|0}}<ref name="gatson" /> | Service: {{cvt|70|km/h|0}} (Initial)<br/>{{cvt|40|km/h|0}} (Current)<ref name="gatson" /> }} | traction = GEC Alsthom GTO-VVVF | traction motors = 3-phase AC induction motor type 4ELA 2552 | poweroutput = {{cvt|840|kW|hp|lk=on}} | electricsystem = {{750 V DC|conductor=third rail}} | collectionmethod = Contact shoe | gauge = {{RailGauge|sg|allk=on}} | deceleration = {{convert|0.9|m/s2|mph/s|abbr=on}} (Service)<br/>{{convert|1.1|m/s2|mph/s|abbr=on}} (Emergency)<ref name="gatson" /> }}
The '''MF 88''' ({{langx|fr|'''M'''étro '''F'''er appel d'offres de 19'''88'''}}; {{langx|en|Steel-wheeled metro ordered in 1988}}) is a steel-wheel variant of electric multiple units used on the Paris Metro. The RATP contracted a consortium of manufacturers, with Ateliers du Nord de la France in charge of the project.
They were built following successful tests of a prototype train-set called the "BOA", derived from the MF 77, which tested new features such as open gangway connections between cars to improve passenger distribution and special bogies to reduce friction caused by the sharp curves found in the Metro network. The MF 88 introduced a number of innovations in its time, including AC induction motors and an on-board computer system using a new standard integrated computing architecture.<ref name="computers">{{cite book |last1=Bancelin |first1=J |last2=Bordenave |first2=H |title=Control, Computers, Communications in Transportation |chapter=Test and Development Bench for an In-Borne Computing Architecture |date=10 July 1990 |page=15-18|doi=10.1016/B978-0-08-037025-5.50008-6 |isbn=978-0-08-037025-5 }}</ref><ref name="computer2">{{cite book |last1=Boullie |first1=JB |last2=Brun |first2=M |chapter=A new rolling stock architecture using safety computers and networks |title=Proceeding International Conference on Dependable Systems and Networks. DSN 2000 |date=6 August 2002 |pages=157–162 |doi=10.1109/ICDSN.2000.857529|isbn=0-7695-0707-7 }}</ref> It is planned for the MF 19 CC rolling stock to replace the MF 88 in 2026.<ref name="replacement">{{cite news |last1=Philippe-Enrico |first1=Attal |title=MF 19, le renouveau des rames fer du métro |url=https://www.railpassion.fr/materiel-actualites-rp/mf-19-renouveau-rames-fer-metro/ |access-date=17 June 2024 |work=Rail Passion (Magazine) |date=10 July 2018}}</ref>
== Design == Carrying on the features of the BOA,<ref name="janes" /> a total of nine MF 88 train-sets were built, which have only ever operated on Line 7bis in a three-car formation. It was the first model with AC motors as opposed to DC, supplied by GEC Alsthom,<ref name="janes">{{cite book |last1=Allen |first1=Geoffrey Freeman |title=Jane's World Railways 1991-92 |date=1 November 1991 |publisher=Jane's Information Group |isbn=9780710609557 |page=74 |edition=33rd }}</ref> and the first to have interconnecting gangways.<ref name="Metropole">{{cite web |url=http://www.metro-pole.net/expl/materiel/mf88/mf88.html |title=Article MétroPole - « Le MF 88 » |language=French |date=2006-01-05 |archiveurl=https://web.archive.org/web/20060716170337/http://www.metro-pole.net/expl/materiel/mf88/mf88.html |archivedate=2006-07-16 }}</ref><ref name="janes" /> The MF 88 was also the first to adopt a new computing architecture, developed by TechnicAtome, over relay-based systems used in older Paris Metro rolling stock.<ref name="computers" /><ref name="computer2" /> It was also the last model not newly built with automatic announcements and with user-activated doors (all subsequent models, as well as more recently the MF 77s on Line 13, have had all doors open at once). However, automatic announcements were later added in the mid-2020's.
The MF 88 introduced an independent-wheeled steering axle design,<ref name="janes"/> but this turned out to cause several problems for RATP and was not adopted in subsequent Paris Metro rolling stock.<ref name="Metropole" /> This design was causing excessive wear on the track<ref name="gatson">{{cite book |last1=Gaston |first1=Jacobs |title=Le métro de Paris : Un siècle de matériel roulant |date=2001 |publisher=La Vie du Rail |isbn=9782902808977 |page=167-170}}</ref> due to a flaw in the chassis, where each intermediate bogie only has one axle, similar to a typical car, bus, some rubber-tyred trains (although the rubber-tyred lines of the Paris Métro use the typical 2-axle bogies), or certain railbuses, but unusual for a more “standard” railcar, especially one powered by electricity.<ref name="technical specifications">[https://www.iledefrance-mobilites.fr/wp-content/uploads/2017/04/Deliberation_no2013-534_-_Schema_directeur_materiel_metro.pdf STIF - ''Schéma directeur du matériel métro''][https://archive.wikiwix.com/cache/index2.php?url=https%3A%2F%2Fwww.iledefrance-mobilites.fr%2Fwp-content%2Fuploads%2F2017%2F04%2FDeliberation_no2013-534_-_Schema_directeur_materiel_metro.pdf%2Findex.html Archived]</ref> The high rate of wear-and-tear of the train-sets has made maintenance much more expensive than expected.
==Technical specifications== * Manufacturers: GEC Alsthom, Faiveley, Renault, ANF * Electric source: {{750 V DC|conductor=third rail}} * Traction: Gate turn-off thyristor (GTO) * Power: 2 motors per motor coach with {{convert|210|kW|hp|abbr=on}} each, {{convert|840|kW|hp|abbr=on}} total per train * Maximum operating speed: {{convert|70|km/h|abbr=on}}, currently reduced to {{convert|40|km/h|abbr=on}} due to rolling stock's condition<ref name="gatson" /> * Bogies: Bi-directional * Length: {{convert|46.44|m|ftin|frac=32}}
thumb|Arrival of a MF 88 on Line 7bis thumb|Departure of a MF 88 on Line 7bis
== Formations == As of 1 September 2022, eight MF 88 trainsets were in service and were formed as shown below. One trainset was scrapped in 2013.<ref>{{cite journal |title=Paris : le matériel RATP du métro à fin 2022|journal=Réseaux urbains|year=2023|last=Colin|first=Pierre|issue=169|pages=41–44|url=https://www.fptu.fr/ru/sommaires.php?ru=169}}</ref>
As of 1 March 2022, eight trainsets are allocated to Pré Saint-Gervais depot for use on Line 7bis.
{| class="wikitable" |- |style="background-color:#ccc;"| | colspan="3" |<small>{{align|left|<- Louis Blanc}}/{{align|right|Pré Saint-Gervais -> }}</small> |-style="line-height: 3.3px; background-color:#{{rcr|Paris Metro|7bis}}" |colspan="7" style="padding:0; border:0;"| |-style="line-height: 6.7px; background-color:#{{rcr|Paris Metro|7bis}}" |colspan="7" style="padding:0; border:0;"| |- ! Car No. !! 1!! 2 !! 3 |- ! Type | M || T || M |- ! Designation | 88M.xxx || 88B. xxx || 88M. xxx |- ! Equipment | VVVF || CP, SIV || VVVF |}
{{Commons category|MF 88}}
== References == {{Reflist}}
{{Paris Metro rolling stock}} {{Paris transport network}}
Category:Paris Metro rolling stock Category:Paris Metro Line 7bis Category:750 V DC multiple units Category:Alstom multiple units Category:Electric multiple units of France Category:Train-related introductions in 1993