Incheon Airport Maglev

The Incheon Airport Maglev was a maglev line in South Korea that opened on 3 February 2016 and closed on 1 September 2023. It was the world's second commercially operating unmanned urban maglev line after Japan's Linimo. The trains were lighter, cutting construction costs in half. The majority of construction was completed by November 2012.

The maglev linked Incheon International Airport Terminal 1 to Long Term Parking, Incheon Airport Administration Complex, Paradise City entertainment precinct, and Yongyu station and Leisure Complex while crossing Yeongjong Island. The line is not part of the Seoul Metropolitan Subway System. It was free of charge for all riders. It initially operated between 09:00 and 18:00. Hours had been extended to between 07:30 and 20:00. Departures were every 15 minutes from all stations. It offered a transfer to Incheon International Airport Terminal 1 station of AREX.

This maglev line specifically utilized electromagnetic suspension (EMS) and linear induction motor (LIM) propulsion. The train was one of the first commercial maglev trains since the 1980s. Two more stages were planned of 9.7 km and 37.4 km. Once completed it would have become a circular line. These lines make up a core project that the Korea Rail Network Authority managed.

Stations
All stations are located in Jung District, Incheon.

Origins
The maglev train, nicknamed ECOBEE, was co-developed by the Korea Institute of Machinery and Materials (known as the KIMM which is part of the Korea University of Science and Technology) and Hyundai Rotem. It is 6.1 km long, with six stations and a 80 km/h operating speed (the design maximum speed is 110 km/h).

This train was part of Korea's Urban Maglev Program (UMP) which started in December 2006. This program reached out to prominent companies and organizations in the railway concentrations previously mentioned. The UMP represents Korea's push for R&D in maglev systems in order to engender a magnetic levitation transportation system to replace Korea's current urban transportation means. This train system is the result of a development project started in 1989 within the Korea Institute of Machinery and Materials (KIMM).

The Ministry of Land, Infrastructure and Transport contributed 59% of the funds, around, with Incheon Airport Corporation spending amounting to 25%, and Incheon City paying  which comes to 6%. Additionally, was spent on research. This totals over of taxpayer money spent on the shortlived project.

Response to the Coronavirus Pandemic
During the COVID pandemic the line was reduced to operate during the am & pm Rush Hours only - departing Airport Terminal 1 Station every 15 minutes from 07:30 to 09:00 and 18:00-1900. The reduced service was still operating in May 2022 but was expected to return to full-time service shortly after.

Closure
At its height in 2019, the Incheon Maglev saw just 4000 passengers each day. This is only 11% of expected usage levels. During the coronavirus pandemic, this number reduced by over 90% to just 300 daily passengers on average.

The line was temporarily closed from 14 July 2022 due to maintenance and repair of the carriages not being completed on time (required every 3 years) as per the Railroad Safety Act.

Changes and potential reopening
At the National Assembly Land, Infrastructure and Transport Committee meeting on 22 August 2022, Rep. Heo Jong-sik (of Dong-gu, Incheon) called for a “plan to reduce operating costs”, as annual maintenance fees hit.

On 17 October 2022, the National Assembly Transportation Committee held an inspection of the Incheon International Airport Corporation. They received stern critiques regarding the cost; it was revealed that Incheon Maglev required of investment over the next 10 years. This is more than the cost of its initial construction.

On 16 June 2023, the Construction and Transportation Committee of Incheon City Council approved plans to convert the track from Maglev to orbital tram tracks. The City Council argued that maintenance costs could be cut by up to 35% due to the difficulty and high cost in purchasing parts for the rare Maglev trains.

A proposal to cut costs was passed at the Incheon City Planning Committee on 26 July 2023. The new plan would reduce the operating time from 13 hours to 6 hours and decrease the number of trains from 103 to 25. It was projected that these changes would cut down annual operating costs from to.

On 3 January 2024, Incheon International Airport Corporation announced that operations are expected to resume from March 2024.

Rolling stock
Hyundai Rotem manufactured the rolling stock for this line and is the entity that managed its development. The 4 trains consist of 2 carriages, namely A and B. Each carriage is 6 m long, 2.7 m wide and 3.45 m high, they weigh 19 tonnes and have a starting acceleration and service brake of 1.1 m/s2.

Past research


Train systems such as the Incheon Airport Maglev use air brakes and electric brakes. However, magnetic levitation trains use regenerative braking and plugging braking as opposed to normal trains using regenerative braking and air braking. Regenerative braking is used when the speed of the motor exceeds the synchronous speed. When this happens, the motor changes current flow so that the motor brakes. After this happens, the excess power is converted to power for the motor. Plugging braking is used when the supply terminals are switched, but it is criticized as a wasteful practice, because in order to switch the terminals, an external resistor needs to be implemented as a stopper for the current flow. As a result, a lot of power is squandered.

With the Urban Transit Maglev (now referred to as the "Incheon Airport Maglev") in South Korea as a test model, a study was conducted on exploring the relationship between the variation of slip frequency and energy efficiency of regenerative braking. The slip frequency decreases the limit for the regenerative extinction point. After testing, researchers noticed that this decrease of the frequency led to a decrease in the conversion time of the phase current back into the system. This decreased the required energy to brake, thus accumulating more regenerated power.