| ALCO HH series | |
| Powertype: | Diesel-electric |
| Builder: | ALCO |
| Wheeldiameter: | 400NaN0 |
| Primemover: | Alco HH600/900: McIntosh & Seymour 531; HH660/1000: McIntosh & Seymour 538 |
| Enginetype: | Inline-6 Four stroke diesel |
| Aspiration: | HH600/660: Naturally aspirated HH900/1000: Turbocharged |
| Cylindercount: | 6 |
| Cylindersize: | 12.5x |
| Displacement: | 9572cuin |
| Length: | 45feet |
| Poweroutput: | 6000NaN0, 6600NaN0, 9000NaN0, or 10000NaN0 |
| Aarwheels: | B-B |
| Totalproduction: | HH600: 79 HH660: 43 HH900: 21 HH1000: 34 |
The ALCO HH series was an early set of diesel switcher locomotives built by the American Locomotive Company (ALCO) of Schenectady, New York between 1931 and 1940, when they were replaced by the S series: the 660hp S-1 and 1000hp S-2. They were ALCO's first diesel switchers to enter true series production, and among the first land vehicles anywhere to use the revolutionary diesel-electric power transmission.
The "HH" name stood for "High Hood", a name ALCO came eventually to use in an official context, but originally an unofficial name. Model designations such as HH600 are only semi-official. Original ALCO designations were either descriptive or based on the internal order/design number.
A total of 177 of the HH series was produced; comprising one prototype and four production models of varying power outputs.
The first HH series locomotive, ALCO demonstrator #600, was mechanically almost identical to later designs, but the appearance differed. The sides of the locomotive's hood sloped outward from top to bottom, and brake equipment was exposed beneath the cab. It rode on a unique pattern of trucks. After a period of demonstration on a number of railroads, the unit was sold to the New York, New Haven and Hartford Railroad as #0900. This number often was used to describe the locomotive, although the classification on the builder's data card was "404-OE-200". This first unit was built in July 1931.
The locomotive was equipped with a four-stroke McIntosh & Seymour 531 straight-6 diesel engine, powering a General Electric GT551A1 main generator. Four nose-suspended GE-287-D traction motors in the trucks were geared at a ratio of 4.25:1 to the wheels; the motors were cooled by electrically driven traction motor blowers.[1]
The HH600 was nearly identical to the previous #0900 of the New Haven internally and mechanically, but it was clad in new bodywork, with a straight-sided hood and cab sides that came all the way to the frame. The HH600's were powered by 6-cylinder McIntosh & Seymour 531 engines of 600hp. They were built from July 1932 through May 1939; in all, 78 HH600s were constructed. The first-built units had sharp-edged front hood corners, but in 1934 ALCO employed industrial designer Otto Kuhler to clean up the appearance; he curved the corners and recessed the headlight, and all subsequent HH series units were of this style until another restyling in 1938 where the nose was further rounded. Late versions of this locomotive used the 6-cylinder 538 engine.
| Railroad | Quantity | Road numbers | Notes |
|---|---|---|---|
| American Locomotive Company (prototype) | 1 | 600 (1st) | to New Haven 0900 |
| American Locomotive Company (demonstrators) | 5 | 1, 600 (2nd) | 1 to ATSF 2300 |
| 601 | to Lehigh Valley Railroad 105 | ||
| 602 | to Boston and Maine 1102 | ||
| 603 | to Delaware, Lackawanna and Western 401 | ||
| 2 | 2301–2302 |
| |
| 2 | 302–303 | ||
| 1 | 1101 | ||
| 4 | 1020–1023 | 1021 to Houdaille Construction Materials Co. | |
| 1 | 102 | ||
| 1 | 1 | ||
| 1 | 1 | ||
| 7 | 402–408 | 405–406 to Erie Lackawanna as 322-323 | |
| 1 | 209 | ||
| 1 | 601 | ||
| 8 | 9006–9013 | Scrapped 1951 | |
| 1 | 7 | ||
| 2 | 101–102 | ||
| 6 | 614–619 | ||
| New York Central (Boston and Albany Railroad) | 5 | 680–684 | Renumbered 806–810 |
| 10 | 0911–0920 | ||
| 7 | 54–60 | ||
| 1 | 100 | ||
| Portland Terminal Company [Maine] | 4 | 1001–1004 | |
| 6 | 54–59 | ||
| 1 | 31 | ||
| Universal Atlas Cement | 1 | 4 | |
| Total | 79 | ||
The HH900 was a 900 hp (670 kW) version of the HH series using a turbocharged version of the McIntosh & Seymour 531 engine. Both turbocharged models (HH900 and HH1000) needed a greater cooling capacity, and this was reflected in the larger bodyside radiator space of both models, which distinguishes them from the lower-powered HH600 and HH660. The 21 HH900 units were produced between March 1937 and January 1939, after which they were supplanted by the McIntosh & Seymour 538T-engined HH1000. Several HH900s were built with the 538T engine.
| Railroad | Quantity | Road numbers | Notes |
|---|---|---|---|
| American Locomotive Company (demonstrator unit) | 1 | 101 | to CRI&P 730 |
| 8 | 81–88 | ||
| 1 | 402 | ||
| 1 | 50 | ||
| 3 | 90–92 | ||
| 1 | 207 | to South Buffalo Railway 70 | |
| 2 | 40–41 | ||
| 2 | 50–51 | ||
| 2 | 211–212 | ||
| Total | 21 | ||
The HH660 started production in ALCO's lineup in October 1938; 43 examples were built until April 1940. It used a naturally aspirated version of the 6-cylinder McIntosh and Seymour 538 engine, producing 660hp. Externally, HH660s were indistinguishable from late HH600s.
| Railroad | Quantity | Road numbers | Notes |
|---|---|---|---|
| American Locomotive Company (plant switcher) | 1 | 4 | |
| 1 | 1900 | ||
| 1 | 1162 | ||
| 1 | 43 | To Relco - 1966, to WNYRHS - 2000 | |
| Chicago, Milwaukee, St. Paul and Pacific Railroad (“Milwaukee Road”) | 4 | 1600–1603 | Renumbered 980–983
|
| 3 | 409–411 | 409–410 to Erie-Lackawanna Railway 324–325 | |
| 3 | 210–212 | 211 to Gopher State Scrap and Metal | |
| 4 | 302–305 | 305 to Erie-Lackawanna Railway, same number | |
| 1 | 101 | ||
| Inland Steel | 1 | 50 | |
| 1 | 10 | ||
| 2 | 951–952 | ||
| 1 | D939 | To Glacier Sand & Gravel | |
| 10 | 0921–0930 | 0924 to Penn Central 9411 in 1969 | |
| 3 | 125–127 | 125–126 to Walla Walla Valley Railway 770, 775;
| |
| 3 | 1001–1003 | ||
| 1 | 50 | ||
| 2 | 100, 150 | ||
| Total | 43 | ||
The HH1000 replaced the HH900, with the new McIntosh and Seymour 538T engine, turbocharged to produce 1000 hp (750 kW), a 100 hp (75 kW) increase from the previous model. They were produced between May 1939 and December 1940; 34 were built.M&STL D539 was the only HH1000 built with the 531T engine.
| Railroad | Quantity | Road numbers | Notes |
|---|---|---|---|
| American Locomotive Company (demonstrator unit) | 1 | 1000 | |
| 12 | 2310–2321 | ||
| 1 | 600 | ||
| 1 | 89 | ||
| Chicago, Milwaukee, St. Paul and Pacific Railroad (“Milwaukee Road”) | 1 | 1671 | |
| 3 | 202–203 | ||
| 4 | 103–106 | ||
| 1 | D-539 | Renumbered 92; to Chicago and North Western Railway | |
| 1 | 9102 | ||
| 2 | 1–2 | ||
| 7 | 900–906 | ||
| Total | 34 | ||
| Overall length | 45 ft 2.75 in | 13.79 m | |
| Between bolster centers: | 21 ft 3 in | 6.48 m | |
| Truck wheelbase: | 8 ft 0 in | 2.44 m | |
| Width over grabirons: | 9 ft 10 in | 3.00 m | |
| Height above rails: | 14 ft 3 in | 4.34 m | |
| Wheel diameter: | 40 in | 1.02 m | |
| Fuel capacity: | |||
| Engine (HH600): | McIntosh & Seymour 531 | ||
| Power (HH600): | 600 hp | 450 kW | |
| Engine (HH900): | McIntosh & Seymour 531T (turbocharged) | ||
| Power (HH900): | 900 hp | 670 kW | |
| Engine (HH660): | McIntosh & Seymour 538 | ||
| Power (HH660): | 660 hp | 500 kW | |
| Engine (HH1000): | McIntosh & Seymour 538T (turbocharged) | ||
| Power (HH1000): | 1000 hp | 750 kW | |
| Main generator: | |||
| Traction motors: | |||
| Standard gearing: | |||
| Weight: | |||
A few HH series switchers still survive in revenue service, and more are in museums. Working HH locomotives include an HH660 at Gopher Scrap in Mankato, Minnesota, one owned by the Western New York Railway Historical Society, and one from the Delaware-Lackawanna Railroad owned by Genesee Valley Transportation Company at Scranton, Pennsylvania.[2]
Among the preserved locomotives are an HH600, four HH660s and an HH1000. Birmingham Southern #82, the sole surviving HH900, is on static display at the Heart of Dixie Railroad Museum in Calera, Alabama.
