RSD 7 - MagnumMacKivler/RLCPT2 GitHub Wiki
Image Copyright ATSF, Rika's personal collection
Introduced in early 1954, the RSD-7 was Alco's response to Fairbanks Morse's iconic H24-66 "Train Master". Pioneering a new full height carbody, the RSD-7 could be equipped with dynamic brakes and a steam generator simultaneously without sacrificing capacity on either, something that hadn't been available before on Alco's road switchers such as the RS-3. Initially, two 2250 horsepower demonstrators (DL600 and DL601) with 16-244G engines were built with the specification DL-600, they went on a tour of the United States for the majority of 1954, eventually being sold to ATSF in mid-1955. Shortly after the demonstrators were sold, the DL-600 specification was revised slightly, the new DL-600A had an increased length to fit clasp brake trucks and an improved 16-244H engine rated at 2400 horsepower, ATSF 602 being the first production unit, rolling off the line in October 1955. The RSD-7 was the only freight locomotive to be powered by a 16-244, adding to that it was one of the few locomotives to be built with the much-improved 244G and 244H, two variations which turned the 244 into a very solid engine. Despite being a pioneer of its time, the RSD-7 sold considerably awful, especially when compared to EMD's SD24 and FM's H24-66. The RSD-7's replacement, the RSD-15, was much improved and was powered by Alco's now notorious 251 engine, boosting reliability and performance significantly. Unfortunately, due to many factors such as the time peirod they were built and what they were as a locomotive, none are known to exist today.
PT-Specific Information
| General Info | - |
|---|---|
| Prime Mover | ALCO 16-244H (1) |
| Horsepower | 2400 (1) |
| Truck Type | Alco Trimount C |
| Axles | 6 |
| Traction Motors | 6 |
| Minimum Weight | 325,000 lbs |
| Maximum Weight | 390,000 lbs (2) |
| Model Base Speed | 65 MPH |
| Top Speed | 65, 75, or 80 |
| Electrical System | - |
|---|---|
| Generator Max Current | 5400 Amps (1) |
| Max Traction Motor (TM) Current | 1800 Amps (1) |
| Max Continuous TM Current | 1085 Amps |
| Traction Motor Type | DC |
| Factor of Adhesion | 25% |
| Transition Mode | Automatic with Selector |
| Transition Groups | 2, 2, 1, 1 |
| Transition Shunts | 1, 0.75, 1, 0.75 |
| Generator Transition | No |
| Traction Control | APR |
| Dynamic Braking (DB) Mode (if used) | Mechanical Blowers @ 50% |
| DB Max Current | 1800 Amps (1) |
| DB Max Continuous Current | 830 Amps |
| Blended Braking | No |
| Miscellaneous | - |
|---|---|
| Head-End Power (HEP) | No |
| HEP Power Consumption | N/A |
| HEP Standby/Run Mode | N/A |
| Load Ramp Speed | 10 Amps/Tick |
| TM Overload Protection | No |
| Starter Mode | Latched Primer, Manual Start |
| Air Brake Schedule | 24-RL |
| Compressor CFM | 307 (Wabco 3CDB @ 1000 RPM) |
| Main Reservoir Volume | 35.24 Cubic Feet |
Notes
(1): The first two demonstrators were powered by 16-244G engines and had earlier GE 752 motors changing the horsepower to 2250, the Max TM Current and DB Max Current to 1500 Amps, and Gen Max Current 4500 Amps.
(2): This is Alco's listed weight from an RSD-7 operators manual, however, if requested you could get the RSD-7 ballasted up to 400,000lb; ATSF's ordered units (602-611) exercised this option and were ballasted at 398,000lbs, a side effect of this was fitting anything other than the base fuel tank was impossible due to the ballasting block under the frame.