The ALCO DL-202-2 and DL-203-2diesel-electric locomotive (known informally as the Black Maria) was an experimental freight locomotive produced by ALCO of Schenectady, New York. The primary diesel builders Alco, Baldwin and EMD pushed the War Production Board (WPB) for more opportunities to build more diesels. The Transportation Equipment Division of the WPB announced a production schedule on December 10, 1943 that allowed Alco to build one 4500 horsepower experimental diesel locomotive. This experimental diesel locomotive was to be built in the fourth quarter of 1944. The two A units were built in January 1945 and the B unit at a later date in 1945. The two A units were put on test at Building No. 37 at Schenectady to work out problems with the connecting rods and turbocharger in the Alco 241 engine. The total production run included 2 cab DL202-2 A units, and a single DL203-2 B cabless booster) unit. The locomotives were powered by a V12ALCO 241diesel engine, rated at 1,500 hp (1.1 MW). The units were released for test in September 1945. The locomotive could attain a top speed of 80 km/h (50 mph) (Freight) and 125 km/h (78 mph) (Passenger). With the B-Bwheel arrangement and carbody construction, equipment layout and electrical gear these experimental units were the immediate predecessors of the FA units to come in early 1946. Outwardly, the bodies strongly resembled those on the DL-109, some of which were still under construction at Schenectady in early 1945.
Pre-FA (Black Maria) by W. A. Cuisinier (Preston Cook) Extra 2200 South Issue #34 pp. 17–18 includes line drawings and equipment layouts by Cuisinier.
Kirkland, John F. (Winter 1989). The Diesel Builders Volume 2: American Locomotive Company and Montreal Locomotive Works. Interurban Press. ISBN0-916374-81-5.
Steinbrenner, Richard T. (2003). The American Locomotive Company: A Centennial Remembrance. On Track Publishers LLC, New Brunswick, NJ. ISBN0-911122-07-9. Chapter VII ALCO and World War II pp. 221–230.