The Comeng ( ) is a class of electric multiple unit (EMU) operating on the suburban railway network of Melbourne. Built by their namesake Commonwealth Engineering (abbreviated as Comeng), the trains were introduced in 1981 as a replacement for the Tait and Harris trains. In total, 190 three-car trainsets were built, although 100 three-car sets remain in service and are expected to be retired by 2032.
The fleet underwent two major refurbishments. The first, a mid-life refurbishment, was carried out from 2000 to 2003 by Alstom and EDi Rail. The second, named the Comeng Life Extension Project, completed between 2017 and 2021, aimed to extend the trains' lifespan to at the very least meet their successors entry to service High Capacity Metro Trains and the X'Trapolis 2.0 trains. Alongside these upgrades, a number of minor improvement programs were also conducted on the trains to further enhance their efficiency, safety, and reliability.
With the withdrawal of the Hitachi trains in 2014, the Comeng trains are currently the oldest active in the Melbourne suburban fleet.
Description Comeng trains are single deck and are semi-permanently coupled as M-T-M (motor-trailer-motor) sets. Most frequently, they are coupled as M-T-M-M-T-M (six-car) sets. Comeng trains have power operated doors that must be pulled open manually by hand but are closed by the driver. The trains were the first suburban trains in Melbourne to have air-conditioning in the passenger saloon.Newsrail November 1981 p3 (The older Hitachi trains had driver only air-conditioning fitted more recently.) The design of Melbourne's Comeng trains is closely related to that of Adelaide Metro's diesel-electric 3000 class railcars.
They operate in larger numbers on the Northern, Cross City and Frankston group lines. Since 2017, the Comeng trains have discontinued regular operations on the Burnley and Clifton Hill group lines which are now served exclusively by newer X'Trapolis 100 trains most of the time. The Comeng trains had previously served on the Cranbourne and Pakenham lines until December 2022 and the Sunbury line until February 2026. Since then, the Cranbourne, Pakenham and Sunbury lines were replaced and exclusively served by the High Capacity Metro Trains due to the opening of the Metro Tunnel. As of 10 March 2026, those lines are now operated exclusively by High Capacity Metro Trains.
The Comeng fleet has begun retirement, with many sets being transferred to North Shore and Tottenham to be stored. The stored sets eventually being transferred to Laverton, North Bendigo or McIntyre for scrapping. The fleet will eventually be replaced by the High Capacity Metro Trains (HCMT) and X'Trapolis 2.0 fleet.
History
In late 1977 the Victorian Railways, trading as VicRail, called tenders for 300 new suburban carriages to operate on the Melbourne metropolitan network, arranged as 100 sets of motor-trailer-motor sets, forming the largest passenger rolling stock contract called for an Australian railway at the time. The intent was to replace the remaining timber-bodied Tait and a significant proportion of the Harris sets, particularly in the lead up to the opening of Melbourne's City Loop. The Dandenong factory employed about 450 people during the contract.
Design Experience with the previous Hitachi sets had shown their electrical equipment was reliable, but the combination of a stainless steel car-body combined with a carbon steel framework had caused serious corrosion issues, so an all-stainless steel design was preferred. This placed Commonwealth Engineering, and their Dandenong rolling stock factory, in a prime position to tender, as they held the Australian license for the Budd Company's stainless steel rolling stock construction techniques. Comeng submitted their tender on 10 April 1978, and the contract was awarded in April 1979.
The original carriage design used a stainless steel structure with glass-reinforced plastic (GRP) trimmings, but manufacturing constraints resulted in a whole front panel for each motor car being made with the GRP material, hiding the stainless steel structure.
A full-size, half-length mock-up of a Comeng motor car was constructed at the Dandenong factory to help VicRail staff visualise the final concept. Photos of the mock-up show a dark blue outline around the front of the carriage, stretching down to a pilot just above the rails, and fittings on the exposed stainless steel motor car front including the final marker lights, but also a taildisc on the centre pillar and a destination disc below the driver's window. This design originally included luggage racks above the windows, but these were not provided in the final model. The window surrounds were also GRP, and the internal ceilings were formed with pressed aluminium sheets with recesses for light fittings, derived from a previous Comeng contract for the Hong Kong MTA.
The underframes followed the normal Budd/Comeng technique of 350-grade carbon steel end units, combined with stainless steel side sills and transoms, but with Corten-steel corrugated floor sheets spot-welded to the underframe structure along the whole length of each carriage. This was necessary to achieve VicRail's stated requirement for end-loading strength, which was specified at three times that of the existing rolling stock. The first body shell was railed from Dandenong to Comeng's Granville plant for testing, and passed all tests.
Electrical systems were all centralised to a common control panel, rather than being located with each piece of equipment spread around the carriage underframes.
From a passenger comfort perspective, the carriage design was the extremely large window panes. Previously, all suburban air conditioned rolling stock in Australia had been designed as carriages first, and then handed to air conditioning manufacturers to design and provide the necessary equipment to achieve specified climate control requirements. The Comeng design flipped that script, instead bringing the air conditioning manufacturers onboard much earlier and this allowed a design with a lower profile, avoiding significant projection above the carriage roofs. The air conditioning units were designed to be lowered onto the carbody, automatically connecting to the air ducts and with only a single electrical connection, isolated from the drainage system. This design principle allowed the modules to be exchanged in as little as ten minutes.
Cast-steel bogies were provided by Bradford-Kendall, which led to some internal political issues between them, Comeng, and Australian National Industries.
An unusual but useful feature of the trains was a switch provided in the guard's compartment, which would enable single car operation. When in use, this system would switch off the lights and lock the doors of the leading and middle carriage, leaving only the trailing carriage for passenger use under observation of the guard. This feature was rendered obsolete when two-person crews were abolished on the Melbourne suburban system, and abandoned when the early 2000s refurbishments of the Comeng fleet introduced inter-carriage walkways.
Construction and delivery Stainless steel sheets were seam-welded together, then placed in jigs and rolled to shape to form the carriage bodies, while underframes were inverted for equipment and piping attachment then flipped and mated to the car shells before final fit-out.
A limited 1,500V power supply was provided at the Comeng factory to allow testing of the trains' internal systems before leaving the compound, then as each set of carriages was completed they were tested on a short siding parallel to what is now the Cranbourne railway line, running south-east from the Comeng factory.
Entry to service The first Comeng set, 301M-1001T-302M, entered service on 28 September 1981. By the middle of 1984, 76 sets had been delivered, and some of the older trains, including the last of the Tait rolling stock, had begun to be phased out. Following the operational problems and subsequent failed refurbishment of the Harris fleet, the initial order was increased from 100 to 190 3-car sets, with the aim of completely replacing both the Tait and Harris sets by 1988.
The first sets experienced issues with the GEC traction equipment that had originally been suggested by VicRail, as it had proven successful in Ireland and Hong Kong but was not suited to Melbourne's climate, including higher ambient temperatures and dust issues, particularly affecting the camshafts. These issues were magnified by late component delivery from GEC's factory in England, and discussions between the Comeng team and GEC's chairman led to some sets of equipment being airfreighted over to Dandenong to avoid production line delays.
Electric train drivers were rostered and trained en-masse for use of the new trains, which led to some drivers being taught how to operate the new equipment but then not using that knowledge for months; to overcome the issue Comeng provided electricians in the driving cabins to remind the train drivers how to operate the new equipment.
Set 381M-1041T-382M was the first delivered in the Metropolitan Transit green and yellow scheme, though the sets including 27T and 28T had been repainted (with those cars renumbered 1027T and 1028T respectively) before then.Newsrail April 1984 p.120 Notably, when the 41st set was delivered the front panels of the motor carriages were grey or silver-framed rather than the earlier orange or later yellow.
Due to the ongoing issues with GEC's traction equipment, set 469M-1085T-470M was fitted with AEG camshaft control equipment instead. It performed admirably but due to no further decisions being made, it remained an orphan set.
In parallel with the development of the Comeng fleet, a separate contract had been won by Comeng in early 1981 to refurbish the Harris fleet. This project ended up being more costly and less successful than originally anticipated, and Comeng and the Railways eventually agreed to terminate that project with the fourth four-carriage set and use those resources to extend the new train contract in lieu. The contract extension signed in late 1982 for the Comeng trains saw the total number increase from 100 to 190 three-car trains. The additional trains provided an opportunity for Comeng to introduce a new fabricated bolsterless type of bogie, manufactured by Salzgitter in Germany to the design of Linke-Hoffman Busch (LHB), and fitted with Chopper equipment, which overcame the weight issues of the cast steel Bradford-Kendall bogies and the electrical issues with the GEC traction equipment, while also allowing recycling of the Mitsubishi traction gear originally intended for the Refurbished Harris train project. The new bogies also use Knorr disc brakes rather than traditional tread brakes. The first batch of bogies were provided from Germany, with the balance of manufacturing work split between Comeng and the Railways' Newport Workshops. The disc brake equipment was tested on set 433M-1067T-434M-435M-1068T-436M in the workshops, before that set was converted to the normal configuration on release to VicRail.
As of 15 July 1985, all sets in service except 321M-11T-322M, 317M-9T-318M, and 339M-20T-340M, were converted from the orange livery to the green livery.
The 45th set delivered had custom decals applied to the sides celebrating the halfway point through the order. On the side (above each door) was the quote "45th Super Train from The Met", and the sides also displayed the number 45 in large Numerals below the windows. This was found on two sets, 477M-1089T-478M and 479M-1090T-480M. These had been removed by 1 February 1991. 477M-1089T-478M still remains in service, but 479M-1090T-480M was stored at North Shore before being scrapped in early 2022.Newsrail April 1991 p121