MBTA Kinki Sharyo Type 7
| Industry | Rail vehicle manufacturing |
|---|---|
| Headquarters | Japan |
| Products | Light rail vehicles |
MBTA Kinki Sharyo Type 7 is a light rail vehicle utilized by the Massachusetts Bay Transportation Authority (MBTA) on its Green Line since 1986. This model represents the first railcar manufactured in the United States by the Japanese company Kinki Sharyo. Built during two production runs, from 1986 to 1988 and again in 1997, the fleet consists of 120 cars, with 93 units still active. These high-floor, two-section articulated vehicles have a maximum capacity of 269 passengers, including 46 seated. They operate on a 600 V DC overhead electrical supply collected via pantograph. Early models incorporated electrical systems from Westinghouse, while later versions employed components from Adtranz. The Type 7 supports multiple-unit operation both within its own series and with AnsaldoBreda Type 8 vehicles, providing enhanced operational versatility across the Green Line.
Background
The MBTA’s Green Line is a light rail transit system featuring an underground segment in Boston. To replace the outdated PCC cars, the MBTA introduced the US Standard Light Rail Vehicle (USSLRV) manufactured by Boeing Vertol in 1976. However, these vehicles suffered from persistent problems related to doors, air conditioning, and battery systems. As a result, many were removed from service; out of 175 ordered units, 55 were canceled, and legal action was taken against the manufacturer.
Following this setback, funds from the canceled USSLRV order were redirected toward acquiring new vehicles. The MBTA briefly leased and evaluated the Canadian Light Rail Vehicle from Toronto’s transit system for three months in 1980 but ultimately decided against adopting it due to compatibility issues.
After a competitive bidding process, Japan’s Kinki Sharyo secured the contract in December 1983, marking its debut in the American railcar market. The resulting "Type 7" trains began operating in 1986 under this agreement.
Development
During the 1980s, Kinki Sharyo had exported streetcars to cities such as Cairo and Alexandria in Egypt; however, these models still employed older technologies like suspended electric motors, air brakes, and resistance control systems that did not meet MBTA standards. To overcome these limitations, Kinki Sharyo collaborated with Swiss company SIG, adapting their articulated electric train design used in Utrecht, Netherlands for the Type 7.
Because part of the manufacturing budget came from the Urban Mass Transportation Administration (UMTA), adherence to the Buy American Act was mandatory. This required that over half of all components be produced domestically within the United States and that final assembly take place on the U.S. mainland.
Car body
Similar to the USSLRV design, the Type 7 consists of two articulated sections with driver cabs at both ends. Its frame is constructed from weather-resistant high-tensile steel engineered to endure compressive forces up to approximately 65 tons. The exterior is covered with sound-absorbing materials to minimize noise pollution and insulated with dense glass wool for thermal regulation. Interior wall panels are made of lightweight acrylic resin.
Passenger seating features box-style seats arranged transverse to travel direction on fiberglass-reinforced plastic (FRP) frames with cushioning. Stainless steel handrails are positioned near doorways for standing passengers’ support. An onboard display indicates route destinations, while a stop request device alerts the operator. Passenger doors comprise four panels that fold outward; two internal steps lead to a floor height of 889 mm. Wheelchair access is limited to stations equipped with ramps or lifts due to this elevated floor level.
The vehicle’s driving controls include foot pedals similar to those found in automobiles for both acceleration and braking, with pedal force directly influencing speed modulation. The driver’s cab layout is streamlined with key-type lever switches and function controls for simplified operation.
Equipment
Each vehicle is equipped with two powered bogies located on the cab end and one auxiliary bogie at the articulation joint. These bogies incorporate steel plate frames joined by press welding, conical roller bearings on the wheelsets, and centrally positioned disc brakes. Noise reduction is achieved through V-shaped elastic wheels. The air springs feature automatic height regulation to ensure a stable floor level. Power transmission is facilitated by a two-stage reduction gearbox supported by rubber anti-vibration mounts. Additionally, a bolster anchor fitted with cushioning rubber between the bogie frame and sway pillow minimizes longitudinal vibrations, improving ride smoothness and overall performance compared to the USSLRV.
The control system utilizes a Westinghouse Electric armature chopper control operated via computer, combined with an electric command brake capable of both regenerative and conventional braking functions. Each powered bogie contains two 103 kW electric motors wired in series, each motor independently managed. Redundancy is built into the dual control circuits so that if one fails, the other continues to function.
Climate regulation is provided by a rooftop air conditioning unit offering both heating and cooling, complemented by underfloor heaters. Conditioned air is delivered through side vents, maintaining the desired temperature by mixing recirculated interior air with fresh external air.
Operation
The prototype was finalized in 1985, followed by performance and braking tests at Kinki Sharyo’s factory starting that October. Subsequent evaluations on the MBTA system took place in 1986, including maximum speed trials and radio system verification. After successful validation, commercial service commenced that same year, with mass production units introduced from May onward.
The Type 7 series supplanted the USSLRV fleet, which had been retired due to frequent mechanical failures. The new vehicles earned acclaim for their reliability and operational efficiency. An initial procurement of 50 second-generation cars was succeeded in 1996 by an additional 20 third-generation units equipped with electrical components supplied by Adtranz. These contracts solidified Kinki Sharyo’s reputation as a prominent supplier of light rail vehicles throughout the United States. The first two production runs maintained the USSLRV’s original green and white livery, whereas the third batch adopted a silver metallic and emerald green color scheme before reverting to white and green during later refurbishment efforts. The details regarding vehicle numbering, order dates, delivery periods, and electrical equipment suppliers are outlined below:
| Numbers | Year of order | Year of delivery | Electrical equipment manufacturers | |
|---|---|---|---|---|
| First batch | 3600–3649 | 1983 | 1986 | Westinghouse |
| Second batch | 3650–3699 | 1986 | 1987–88 | Westinghouse |
| Third batch | 3700–3719 | 1995 | 1996 | Adtranz |
In 1999, AnsaldoBreda’s partially low-floor Type 8 vehicles entered service; Type 7 units are capable of multiple-unit operation alongside these trains. To meet requirements set forth by the Americans with Disabilities Act of 1990, the raised-floor Type 7 cars operate in conjunction with low-floor Type 8 vehicles. Commercial use of three-car trains—comprising two Type 7s plus one Type 8—continued until 2016 but was scaled back to two-car sets due to inefficiencies in capacity and occurrences of derailments.
A refurbishment contract was awarded in 2012 to Alstom’s New York facility over 25 years after initial production for upgrades to interiors and control systems. Six units (3665, 3690, 3703, 3711, and 3719) were excluded from this program because of damage or mechanical failure and were subsequently dismantled.
Future Developments
Starting in the 2020s, the entire fleet of Type 7 and Type 8 vehicles will be phased out and succeeded by the Type 10, a fully low-floor light rail vehicle produced by Construcciones y Auxiliar de Ferrocarriles (CAF).