What is Pacer?
{{Use dmy dates|date=March 2016}} {{Infobox train | background = #cc9966 | name = ''Pacer'' | image = Exeter St Davids - FGW 142064 and 143611.jpg | imagealt = | imagesize = 300px | caption = A [[British Rail Class 142|Class 142]] and [[British Rail Class 143|Class 143]] at {{rws|Exeter St Davids}} in 2011 | interiorimage = | interiorimagealt = | interiorcaption = | service = 1984– 2021 (production units) | manufacturer = | factory = | family = ''Pacer'' | replaced = | yearconstruction = 1980–1987 | yearservice = | refurbishment = | yearscrapped = 2020-2022 | numberconstruction = | numberbuilt = 165 sets | numberservice = 15 sets (National Rail) | numberpreserved = | numberscrapped = 37 sets (142/143/144) | formation = | fleetnumbers = | capacity = | operator = [[Great Western Railway (train operating company)|Great Western Railway]] [[Transport for Wales Rail Services|Transport for Wales]] [[Regional Railways]] [[Arriva Trains Northern]] [[Arriva Trains Wales]] [[Arriva Rail North]] [[Northern Rail]] [[Northern Trains]] [[Valley Lines (train operating company)|Valley Lines]] [[Wales & Borders]] [[Wessex Trains]] [[Islamic Republic of Iran Railways]] (1997–2005) | depots = | lines = | carbody = | trainlength = | carlength = | width = | height = | floorheight = | platformheight = | entrylevelorstep = | art-sections = | doors = | maxspeed = 75 MPH | weight = | acceleration = | deceleration = | traction = | engine = | poweroutput = | transmission = | aux = | powersupply = | hvac = | electricsystem = | collectionmethod = | uicclass = | aarwheels = | bogies = | brakes = | safety = | coupling = | multipleworking = | gauge = {{RailGauge|uksg|allk=on}} }} '''Pacer''' trains were [[railbus]]es built by [[British Rail]] between 1980 and 1987. There were several classes of them: [[British Rail Class 140|140]], [[British Rail Class 141|141]], [[British Rail Class 142|142]], [[British Rail Class 143|143]] and [[British Rail Class 144|144]]. They were [[diesel multiple unit]] train