ED4 (Electric trainset)

ED4 (Electric train Demikhovskiy 4-th modification) are a series of Russian electric trainsets, in production since 1996. The trains are produced by DMZ and currently in service on RZD lines in almost every part of the country and former USSR states.

Production history
The ED4 was designed to accommodate Russia's need for a domestically produced electric train-set. Russia's most widely exploited electric trains, the ER1 and ER2 series, were produced by the Rīgas Vagonbūves Rūpnīca (RVR) plant in Latvia before the collapse of the USSR.

Design work began in 1996 on the basis of the earlier ED2 series, which were largely equipped with RVR components. Electronic equipment for the new train was manufactured by The Novocherkassk Electric Locomotive Plant, while the drive-train was built in Novosibirsk. ED4 train-cars are nearly identical to those used by both the ER29, and ED2T trains, differing mainly in having notably wider doors.

After successfully completing testing, the first train entered service at the Mineralnye Vody Depot of the North Caucasus Railway.

Only 5 trains carry the early ED4 identification, as the second variant, ED4M, began exclusive production thereafter. The main difference between the two trains is the equipment and shape of the operator's compartment.

Four of the early ED4 trains are in currently in service on the Moscow Railway, one on the North Caucasian Railway, and one in Belgorod.

ED4MKM-AERO
Mechanically almost identical to the ED4MKM, these trains have an updated interior, modified for the needs of airport commuters. The AERO trains are in service in Moscow and St.Petersburg, serving the Domodedovo, Vnukovo, Sheremtyevo and Pulkovo airports, respectively. The modified door mechanisms of the AERO were used on all later ED4M trains.