Last revised: June 21, 2023
By: Adam Burns
The SD35 was one of the builder's first second-generation models, released during the mid-1960s. While the locomotive was not as successful as some of its other designs it did sell a
few hundred examples during an era when railroads were only starting to realize the benefits of six-axle power.
New features of the SD35, which dated back to the SD28 of 1965 was a redesigned frame and new Spartan Cab, commonly known as the standard cab.
While EMD was experiencing growing competition from General Electric it was still in its prime and would make another run of phenomenal success during this time with models like the GP35, GP38 series, SD40 series, and others.
About a dozen major railroads purchased the SD35 and a number of these remain in service. One example is known to be formally preserved, Baltimore & Ohio #7402 at the Baltimore & Ohio Railroad Museum, as well as the variant SDP35, Seaboard Air Line #1114 in Hamlet, North Carolina.
The SD35 began production in the early summer of 1964. It followed six-axle designs like the SD18, SD28, and SD24 which which saw relatively few sales.
The locomotive utilized General Motors' tried and proven 16-cylinder model 567D3A prime mover, which could produce 2,500 horsepower featuring GM's D67 traction motors that could achieve a starting tractive effort of 90,000 pounds and 50,000 pounds continuous (the continuous rating was actually quite a bit less than what the SD24 offered). Perhaps the most noticeable trait of the SD35 was its carbody.
Beginning with the 35 series, EMD used a "simplified" design, which became standard on virtually all new models until the FRA-mandated safety cab went into effect during the late 1980s/early 1990s.
The long hood was not significantly different from earlier models but the cab, which EMD referred to as the Spartan (otherwise known as the Standard Cab) became an industry classic with a low, short nose and front windshield. While the SD35 was designed for freight service railroads could purchase one with a steam boiler for passenger/commuter operations this option, classified as an SDP35.
Only 35 of this variant were built between July of 1964 and September of 1965 by the Seaboard Air Line (20), Atlantic Coast Line (1), Louisville & Nashville (4), and Union Pacific (10).
They remained the same length as the SD35 but included the above mentioned boiler for passenger use (the boiler used the open, rear porch space).
While not wildly successful, the locomotive sold relatively well and paved the way for the venerable SD40 series. When production had ended in early 1966 eleven different Class I railroads purchased the model with Southern Railway owning the most, 100.
Entered Production | 6/1964 (Demonstrator #7715) |
Years Produced (SD35) | 6/1964 - 1/1966 |
Years Produced (SDP35) | 7/1964 - 9/1965 |
Engine | 567D3A |
Engine Builder | GM |
Horsepower | 2500 |
RPM | 900 |
Cylinders | 16 |
Length (SD35) | 60' 8" |
Height (Top Of Rail To Top Of Cab) | 15' 8 ½" |
Width | 10' 3" |
Weight | 360,000 Lbs |
Fuel Capacity | 3000 Gallons |
Air Compressor | Gardner-Denver |
Air Compressor Model | WBO |
Air Brake Manufacturer | Westinghouse |
Air Brake Schedule | 26L |
Trucks | C-C |
Truck Type | Flexicoil |
Truck Wheelbase | 13' 7" |
Wheel Size | 40" |
Traction Motors | D67 (6), GM |
Primary Generator | D32, GM |
Auxiliary Generator | Delco (A8102) |
Steam Generator (SDP35) | Vapor-Clarkson (model AR4125) |
Alternator | D14 |
MU (Multiple-Unit) | Yes |
Dynamic Brakes | Yes |
Gear Ratio | 62:15 (71 mph), 61:16 (77 mph), 60:17 (83 mph), 59:18 (89 mph) |
Tractive Effort (Starting) | 90,000 Lbs at 25% |
Tractive Effort (Continuous) | 50,000 Lbs at 12 mph (SD35) |
Tractive Effort (Continuous) | 82,100 Lbs at 6.6 mph (SDP35) |
Top Speed | 71 mph - 89 mph |
Total Built = 360
Owner | Road Number(s) | Serial Number(s) | Order Number | Completion Date |
---|---|---|---|---|
Electro-Motive (Demonstrator) | 7715 (became Atlantic Coast Line #1000) | 29035 | 7715 | 6/1964 |
Atlantic Coast Line | 1001-1003 | 29036-29038 | 7715 | 6/1964 |
Baltimore & Ohio | 7400-7419 | 29408-29427 | 7738 | 7/1964-10/1964 |
Chesapeake & Ohio | 7420-7431 | 29428-29439 | 7739 | 9/1964-11/1964 |
Atlantic Coast Line | 1004-1010 | 29594-29600 | 7752 | 11/1964-12/1964 |
Southern Pacific | 4816-4844 | 29830-29858 | 7761 | 12/1964-4/1965 |
Western Maryland | 7432-7436 | 29890-29894 | 5675 | 12/1964 |
Central Railroad of New Jersey | 2501-2510 | 29974-29983 | 7777 | 5/1965 |
Central Railroad of New Jersey | 2511-2512 | 30298-30299 | 7777 | 6/1965 |
Pennsylvania | 6000-6039 | 30388-30427 | 7795 | 2/1965-6/1965 |
Louisville & Nashville | 1200-1210 | 30432-30442 | 7805 | 4/1965-6/1965 |
Louisville & Nashville | 1211-1221 | 30443-30453 | 5690 | 7/1965-8/1965 |
Atlantic Coast Line | 1011-1023 | 30518-30530 | 7815 | 9/1965 |
Baltimore & Ohio | 7437-7440 | 30706-30709 | 7828 | 9/1965 |
Chesapeake & Ohio | 7428 | 30740 | 7830 | 8/1965 |
Chesapeake & Ohio | 7425 | 30741 | 7841 | 8/1965 |
Norfolk & Western | 1500-1520 | 30761-30781 | 7819 | 6/1965-8/1965 |
Norfolk & Western | 1521-1529 | 30782-30790 | 7820 | 8/1965 |
Central of Georgia | 215-224 | 30796-30805 | 7837 | 1/1966 |
Southern | 3000-3060 | 30806-30866 | 7833 | 9/1965-12/1965 |
Southern | 3061-3099 | 30867-30905 | 7838 | 12/1965-1/1966 |
Norfolk & Western | 1554-1559 | 31136-31141 | 7853 | 11/1965 |
Norfolk & Western | 1560-1579 | 31142-31161 | 7854 | 11/1965-12/1965 |
Norfolk & Western | 1530-1553 | 31162-31185 | 5698 | 10/1965-11/1965 |
Total Built = 15
Owner | Road Number(s) | Serial Number(s) | Order Number | Completion Date |
---|---|---|---|---|
Louisville & Nashville | 1700-1703 | 30454-30457 | 5691 | |
Atlantic Coast Line | 550 | 30531 | 7816 | 9/1965 |
Union Pacific | 1400-1409 | 30671-3068 | 7824 | 8/1965-9/1965 |
Others who purchased the locomotive included the Atlantic Coast Line (24, numbered 1000-1023), Baltimore & Ohio (24, numbered 7400-7419, 7437-7440 the railroad employed them in West Virginia for use in coal drag service), Central of Georgia (10, numbered 215-224), Jersey Central (12, numbered 2501-2512), Chesapeake & Ohio (12, numbered 7420-7431, L&N (22, numbered 1200-1221), Norfolk & Western (80, numbered 1500-1579 also used in coal drag service), Pennsylvania (40, numbered 6000-6039), Southern (100, numbered 3000-3099), Southern Pacific (29, numbered 4816-4844), and Western Maryland (5, numbered 7432-7436).
Of note, EMD's demonstrator #7715 was picked up by the ACL. Today, places you can find SD35s in regular service include Montana Rail Link, Squaw Creek Southern Railroad, and Norfolk Southern has converted former N&W #1530 into a test locomotive.
Dec 04, 23 11:45 AM
Dec 03, 23 10:23 PM
Dec 03, 23 10:51 AM
Wes Barris's SteamLocomotive.com is simply the best web resource on the study of steam locomotives.
It is difficult to truly articulate just how much material can be found at this website.
It is quite staggering and a must visit!