The MF 88 (French: Métro Fer appel d'offres de 1988; English: Steel-wheeled metro ordered in 1988) is a steel-wheel variant of electric multiple units used on Paris's Métro system. RATP contracted a consortium of manufacturers, with Ateliers du Nord de la France in charge of the project.

MF 88
MF 88 trainset at Louis Blanc station on Line 7bis.
Interior of MF 88 trainset
In service1993–present
ManufacturerGEC Alsthom, Faiveley, Renault, ANF
ReplacedSprague-Thomson
Constructed1990–1992
Scrapped2013
Number built27 cars (9 trainsets)
Number scrapped3 cars (1 trainset)
SuccessorMF 19
Formation3 cars per trainset
Capacity425 people per trainset
OperatorsRATP
Lines servedParis MétroParis Métro Line 7bis
Specifications
Train length45.44 m (149 ft 1 in)
Car length15.15 m (49 ft 8 in)
Maximum speed
  • Design: 80 km/h (50 mph)[1]
  • Service: 70 km/h (43 mph) (Initial)
    40 km/h (25 mph) (Current)[1]
Traction systemGEC Alshtom GTO-VVVF
Traction motors3-phase AC induction motor type 4ELA 2552
Power output840 kW (1,130 hp)
Deceleration0.9 m/s2 (2.0 mph/s) (Service)
1.1 m/s2 (2.5 mph/s) (Emergency)[1]
Electric system(s)Third rail750 V DC
Current collector(s)Contact shoe
UIC classificationBo'Bo'+2'2'+Bo'Bo'
Track gauge1,435 mm (4 ft 8+12 in) standard gauge

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 Métro 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.[2][3] It is planned for the MF 19 rolling stock to replace the MF 88 in 2025.[4]

Design

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Carrying on the features of the BOA,[5] 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, supplied by GEC Alsthom,[5] as opposed to DC and with interconnecting gangways.[6][5] 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.[2][3] It also introduced an independent-wheeled steering axle design,[5] but this turned out to cause several problems for RATP and was not adopted in subsequent Paris Metro rolling stock.[6]

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). The high rate of wear-and-tear of the train-sets has made maintenance much more expensive than expected. The independent-wheeled steering axle design was found to be problematic and was causing excessive wear on the track.[1] This is because of the design flaw in the chassis, 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.[7]

Technical specifications

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  • Manufacturers: GEC Alsthom, Faiveley, Renault, ANF
  • Electric source: Third rail750 V DC
  • Traction: Gate turn-off thyristor (GTO)
  • Power: 2 motors per motor coach with 210 kW (280 hp) each, 840 kW (1,130 hp) total per train
  • Maximum operating speed: 70 km/h (43 mph), currently reduced to 40 km/h (25 mph) due to rolling stock's condition[1]
  • Bogies: Bi-directional
  • Length: 46.44 metres (152 ft 4+1132 in)
Arrival of a MF 88 on Line 7bis
Departure of a MF 88 on Line 7bis

Formations

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As of 1 September 2022, eight MF 88 trainsets were in service and were formed as shown below. One trainset was scrapped in 2013.[8]

As of 1 March 2022, eight trainsets are allocated to Pré Saint-Gervais depot for use on Line 7bis.

 
<- Louis Blanc
/
Pré Saint-Gervais ->
 
 
Car No. 1 2 3
Type M T M
Designation 88M.xxx 88B. xxx 88M. xxx
Equipment VVVF CP, SIV VVVF

References

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  1. ^ a b c d e Gaston, Jacobs (2001). Le métro de Paris : Un siècle de matériel roulant. La Vie du Rail. p. 167-170. ISBN 9782902808977.
  2. ^ a b Bancelin, J; Bordenave, H (10 July 1990). "Test and Development Bench for an In-Borne Computing Architecture". Control, Computers, Communications in Transportation. p. 15-18. doi:10.1016/B978-0-08-037025-5.50008-6. ISBN 978-0-08-037025-5.
  3. ^ a b Boullie, JB; Brun, M (6 August 2002). "A new rolling stock architecture using safety computers and networks". Proceeding International Conference on Dependable Systems and Networks. DSN 2000. pp. 157–162. doi:10.1109/ICDSN.2000.857529. ISBN 0-7695-0707-7.
  4. ^ Philippe-Enrico, Attal (10 July 2018). "MF 19, le renouveau des rames fer du métro". Rail Passion (Magazine). Retrieved 17 June 2024.
  5. ^ a b c d Allen, Geoffrey Freeman (1 November 1991). Jane's World Railways 1991-92 (33rd ed.). Jane's Information Group. p. 74. ISBN 9780710609557.
  6. ^ a b "Article MétroPole - « Le MF 88 »" (in French). 2006-01-05. Archived from the original on 2006-07-16.
  7. ^ STIF - Schéma directeur du matériel métroArchived
  8. ^ Colin, Pierre (2023). "Paris : le matériel RATP du métro à fin 2022". Réseaux urbains (169): 41–44.