Korail Class 1000

When Seoul Subway Line 1 first opened, the Class 1000 cars were arranged in six-car trains, and were expanded to eight-car trains between 1980-1981 before being expanded to 10 cars by the 1990s. A six-car formation was as following (where YY is one integer greater than XX):

• 10XX - Tc (trailer driving car)
• 13XX - M (air compressor, battery, main resistor and controller)
• 16XX - M' (transformer, SIV, pantograph)
• 13YY - M
• 16YY - M'
• 10YY - Tc

An eight-car formation was as following (where YY is one integer greater than XX, and ZZ is one integer greater than YY):

• 10XX or 11XX - Tc (trailer driving car)
• 13XX or 14XX - M (air compressor, battery, main resistor and controller)
• 16XX or 17XX - M' (transformer, SIV, pantograph)
• 13YY or 14YY - M
• 16YY or 17YY - M'
• 13ZZ or 14ZZ - M
• 16ZZ or 17ZZ - M'
• 10ZZ or 11ZZ - Tc

First batch car 1115 preserved at the Korean Railroad Museum.

Trains 1-01~1-41 were 1st generation trains and were introduced from 1974 to 1979. Their general appearance was similar to Japanese EMUs built around their time; the earliest cars were even assembled by various Japanese railcar manufacturers. All other cars were built by Korean companies including Daewoo Heavy Industries under license. All trains were assigned to Guro Depot and had the old Korean National Railroad (KNR) livery up to their retirement. The cars were nicknamed the initial rheostat cars (초저항).

The first generation of Seoul Metro 1000-series trains are identical to these trains, and other Seoul Metro trains had their designs derived from these trains.

The first batch of 1st generation trains consisted of 126 cars that were originally linked as 21 six-car trains. The cars were manufactured in 1974 under Kawasaki Heavy Industries, Kinki Sharyo, Tokyu Car Corporation (now JTEC), and Nippon Sharyo.

As ridership increased on Line 1, the trains were rearranged into eight-car trains in the 1980s. As this rearrangement occurred, seven of the trains lost their four motor cars, which were given to the other 14 cars. In place, 42 motor cars were manufactured in Korea between 1980 and 1981 for the seven donor trains. Finally, the trains were extended to ten cars from 1984 to 1985 with two unpowered cars each manufactured in Korea during that time.

In the 1990s, the trains received their current numbers. The 14 trains that utilized eight Japanese-made cars were numbered as trains 1-01~1-14, while the seven that lost their original motor cars were renumbered to 1-29~1-35.

The train that became train 1-02 was involved in an accident at the Hankuk University of Foreign Studies station on October 2, 1984, that led to two damaged cars (a driving car and a motor car) being scrapped and the rest of the train being placed out of service. The train that became train 1-14 experienced a similar accident at Incheon station and received the driving car that survived from the 1984 accident to replace the one driving car that was heavily damaged. In turn, the two driving cars in the out-of-service train were eventually replaced by second batch driving cars, and the motor car was replaced by a new car built in 1986.

The trains were replaced by the Class 311000 trains. They were retired between 1998 and 1999, except for train 1-02, which was kept in service until June 2004. After trains 1-29~1-35 were retired, their motor cars were linked with other trains until 2006, and their unpowered cars (1829-1835 and 1929-1935) were rebuilt into driving cars by Rotem in 2002 and received new front ends. They were renumbered to cars 1088-1094 and 1188-1194 and were linked with newer first generation cars. The cars were replaced with 3rd generation Class 311000 trains and taken out of service in 2006 when they finally reached their 25-year lifespans, and were stored at the Byeongjeom Car Depot until 2011, when they were finally taken off property to be scrapped or repurposed.

The second batch of 1st generation trains consisted of 126 cars that were originally linked as 21 six-car trains. The cars were manufactured from 1976 to 1979 under Daewoo Heavy Industries.

As ridership increased on Line 1, the trains were rearranged into eight-car trains in the 1980s. As this rearrangement occurred, seven of the trains lost their four motor cars, which were given to the other 14 cars. In place, 26 motor cars were manufactured in Korea between 1980 and 1981 for four of the seven donor trains; one received only two motor cars and ran as a four-car train on the Yongsan-Seongbuk shuttle line, and the other two (four driving cars) were held out of service. From 1984 to 1986, the 18 eight-car trains were extended to ten cars, the four-car train was extended to eight cars, a new four-car train was formed, and the remaining two driving cars were donated to the train that would become train 1-02. Finally, in 1989, the two eight-car trains and the four-car train were extended to ten cars with second generation cars built then.

In the 1990s, the trains received their current numbers. The 14 trains that utilized eight original cars were numbered as trains 1-15~1-28, while the remaining six that lost their original motor cars were renumbered to 1-36~1-41.

The trains were replaced by the Class 311000 trains. They were gradually retired between 2000 and 2004; the last trains, trains 1-26~1-28 and 1-41, were retired in June 2004. However, due to their less advanced age, the powered cars in trains 1-36~1-41 and all unpowered cars were saved from retirement and linked with other trains until at least 2006. Many of the cars built from 1984 to 1986 were even refurbished in 2006-2007 and were not retired until September 2014, when the final unpowered cars in 2nd generation train 1-55 were retired with the rest of train 1-55, marking the end of service life of the first generation trains.

Second batch train 1-62 departing Noryangjin.

Refurbished 2nd batch car 1182 (ex-1942) at Yeongdeungpo Station as a Yongsan-Dongincheon express train.

Trains 1-42~1-73 were 2nd generation trains and were introduced from 1986 to 1992. The 2nd batch trains were introduced to supply more trains to Line 1. Several additional 2nd generation cars were built to lengthen first generation trains to ten cars.

The 2nd generation featured a redesigned car body. The front end of the train was changed completely, and a train event recorder was introduced. Unlike the 1st generation trains, the 2nd generation trains were delivered with air-conditioning; thus SIV systems were introduced to power the air conditioners. All trains had the old Korean National Railroad (KNR) livery, but received the new livery following overhaul. Trains 1-42~1-63 were built from 1986 to 1989 with long, rectangular-windowed doors while trains 1-64~1-73 were built from 1991 to 1992 with short, square-windowed doors. However, many cars with rectangular-windowed doors have been refitted with 1st batch trains' doors; car 1162 was the last car with rectangular-windowed doors until its retirement in July 2016. The cars were nicknamed the middle rheostat cars (중저항).

The first batch of 2nd generation trains consisted of train 1-42~1-63. The cars were manufactured from 1986 to 1991. As built, trains 1-42~1-49 were ten cars long, trains 1-50~1-56 were six cars long and ran on the Ansan Line, and trains 1-57~1-63 were four cars long and ran on the Yongsan-Seongbuk shuttle line. Ten additional cars were built to lengthen first generation trains 1-39~1-41 to ten cars.

As ridership increased on Line 1, trains 1-50~1-53 and 1-57~1-63 were lengthened with third generation cars from 1994 to 1997. As this rearrangement occurred, trains 1-50~1-53 and 1-59~1-61 were lengthened to ten cars, and trains 1-57~1-58 and 1-62~1-63 were lengthened to six cars for Ansan Line service.

In 1999, three unpowered cars (two from train 1-42 and one from train 1-43) were rebuilt into driving cars by Daewoo Heavy Industries. They were renumbered to cars 1082, 1182, and 1087 (former trailer car 1842, 1942, and 1943 respectively),[1] and were linked with 1st generation cars. Because no car numbered 1187 was built, car 1087 ran with 3rd generation car 1186 and was retired in 2001.[2] Meanwhile, 1082 and 1182 lasted until 2006, when they were pulled from service due to structural integrity issues, stored at the Byeongjeom Car Depot until the end of 2011, and then scrapped.

All but four trains were overhauled between 2007 and 2008. Trains 1-53, 1-57, 1-63, and 1-65 were prematurely retired in 2006, because they were coupled with eight aging 1st generation cars each, so it was found to be easier to retire the trains instead of overhauling them to be fire-resistant. They were stored at the Byeongjeom and Guro train depots and taken off property before the end of 2015.

On May 1, 2010, train 1-58 was wrecked in a collision with Class 311000 train 311-74 (which was known as Class 5000 train 5-75 at the time of the collision). Car 1158 suffered significant damage while other cars behind it received minor damage.[3] The whole train was retired and most cars were scrapped shortly after.[4]

Both unpowered cars of 1-39~1-40 and one car in train 1-41 were converted into unpowered cars and could be found in Class 311000 trains 311-39~311-41 until 2018, when they were replaced with other Class 311000 cars or Class 341000 cars.[5] Meanwhile, cars 1441, 1541, 1641, and 1741 were used in 2nd batch trains after the retirement of train 1-41, but all cars were retired with train 1-58 on May 1, 2010 when the whole train was damaged in an accident.[6]

The overhauled trains were replaced by the Class 311000 trains. They were retired between 2012 and 2015. 3rd generation cars built in 1996 that were used to extend the trains were retained for use in other trains.

The second batch of 2nd generation trains consisted of train 1-64~1-73. The cars were manufactured from 1991 to 1992. As built, trains 1-67~1-73 were ten cars long and trains 1-64~1-66 were six cars long and ran on the Ansan Line. Additional cars were built to lengthen first generation trains to 10 cars.

All but one train were overhauled between 2007 and 2008. Train 1-65 was prematurely retired in 2006, because it was coupled with eight aging 1st generation cars, so it was found to be easier to retire the train instead of overhauling it to be fire-resistant. It was stored around the system before being taken off property in 2011 or 2012.

The overhauled trains were replaced by the Class 311000 trains. They were retired between 2015 and March 30, 2017, when the last train, train 1-73, made its final run. After retirement, parts of trains 1-72 and 1-73 were used on the Yeongdong Line for testing in mid-2017 before being stored out of service again. In a surprise move, cars 1673 and 1773 were brought back into service in March 2019, when they replaced two powered cars in train 1-79. The cars were retired again in mid-November 2019 when train 1-79 was retired, marking the end of service life of the second generation trains.

3rd batch train 1-83 leaving Singil Station

Trains 1-74~1-81 and 1-83~1-86 were third generation trains and were introduced from 1994 to 1997. They were introduced to supply more trains to Line 1. Many additional 3rd generation cars were built to lengthen second generation trains.

The trains share a similar front end design with the Class 341000 and 351000 trains (as their front ends were derived from those trains' designs), but are otherwise identical to the other Class 1000 trains, especially the second generation. Therefore, they only operate with other Class 1000 cars. All trains were delivered in the old Korean National Railroad (KNR) livery but they have received new livery following overhaul. The cars were nicknamed the new rheostat cars (신저항).

The first batch of 3rd generation trains consisted of train 1-74~1-79. The cars were manufactured from 1994 to 1995 by Daewoo Heavy Industries under model "DEC-13". All new trains are ten cars long; six additional cars were built to lengthen second generation trains 1-59~1-61 from four to six cars for Ansan Line service.

All of train 1-74 sans the driving cars (made excessive when 2nd generation train 1-62 was retired) and the additional cars for trains 1-59~1-61 were retired between 2015 and 2016. Two powered cars from train 1-79 were retired in March 2019 because of mechanical issues; as a result, two 2nd generation powered cars were temporarily brought back into service to replace those cars. Trains 1-75~1-79 were retired in mid-November 2019, and the driving cars in 1-74 were retired in May 2020.

The second batch of 3rd generation trains consisted of train 1-80, 1-81, and 1-83~1-86. The cars were manufactured from 1996 to 1997 by Hyundai Precision. Train 1-80 has always been ten cars long, trains 1-81 and 1-83 were originally eight cars long, and trains 1-85 and 1-86 utilized older trains as only two driving cars for each train were manufactured. Many additional cars were built to lengthen second generation trains 1-50~1-53 and 1-57~1-63, along with rebuilt train 1-82; trains 1-50~1-53 and 1-59~1-61 were lengthened to ten cars, while trains 1-57, 1-58, 1-62, and 1-63 were lengthened from four to six cars.

Eight of the additional cars were retired in 2017 when second generation train 1-64 was retired, and eight more were retired in May 2020 when third generation train 1-74 was retired. All the other 2nd batch of third generation trains were expected to be retired in 2021, but after a derailment involving train 1-83 in April 2020,[7] the remaining trains were taken out of service by June 2020 due to perceived safety issues.