Train Makeup
Railroads define various restrictions on train makeup. These can be attributes of the entire train - length, weight, HP per Ton - or on the arrangement of locomotives and cars within a train.
BNSF
Length
| Description | Length (ft) | Distance (ft) between DP consists |
|---|---|---|
| Non-DPU | 10,000 | |
| One DPU consist, Intermodal | 10,000 | |
| One DPU consist, other | 8,500 | |
| Multiple DPU consists | 13,000 | 6,500 between each consist |
Locomotives
Trains are limited in power by Rated Powered Axles (RPA). BNSF system instructions (as of 2010) allow for two possible DPU configurations:
- One DPU consist, at least halfway through the train (including placement at the rear-end)
- Two DPU consists, with one mid-train consist (within 20 cars of the middle of the train), and one rear-end consist.
When using DPU, the total Rated Powered Axles of the leading consist cannot exceed the RPA of remote consists by more than 16.
Empty bulk trains are limited to a maximum of 9000 HP, and at least one locomotive must be active in each DP consist, meaning that empty bulk trains running with DP must have one locomotive active at the head end, and one active at the rear.
| Description | Head end RPA | Mid train RPA | Rear end RPA |
|---|---|---|---|
| Intermodal | 48 | 24 | 16 |
| Manifest | 42 | 24 | 16 |
| Empty Bulk | 16 | 8 | 8 |
| Loaded Bulk | 32 | 40 | 24 |
Rated Powered Axle listing
| Locomotive | RPA |
|---|---|
| All SW/GP units not otherwise listed | 4 |
| GP60M / GP60B | 5 |
| All SD units not otherwise listed | 6 |
| SD60 / SD60M | 7 |
| SD70M | 7 |
| SD75M | 7 |
| C40-8 | 7 |
| C44-9W | 8 |
| ES44DC | 8 |
| AC440CW | 8 |
| ES44AC | 8 |
| ES44C4 | 8? |
| SD70MAC | 8 |
| SD70ACe | 8 |
HP per Ton
Southern Transcon, East
On the Southern Transcon, trains east of Clovis, NM should be regulated to (i.e. must not exceed) the following maximum HP/Ton limits:
| Train Symbol | HP/T |
|---|---|
| Z, section numbers 7-9 | 3.0 |
| Z, section numbers 1-6 | 2.5 |
| Q, S, H, or M | 2.0 |
On most sections of line, these limits are very generous, and trains can run at much lower HP/T ratings - although high priority Z trains do often run at or near these limits.
Additional units are routinely carried UIT on westbound trains in preparation for steeper grades west of Clovis, or having been set UIT after passing Clovis eastbound.
Southern Transcon, West
West of Clovis, trains must meet a minimum of 1.4 HP per Ton.
Cajon Pass
Trains proceeding over Cajon Pass must meet the following restrictions:
| Train Description | HP/T Cajon Westbound | HP/T Cajon Eastbound | Tons Cajon Westbound | Tons Cajon Eastbound |
|---|---|---|---|---|
| DP Intermodal | 1.8 | 2.3 | ||
| DP Coal | 1.8 | 2.3 | ||
| DP Other | 1.8 | 2.3 | ||
| Intermodal | 2.0 | 2.5 | 11,500 | 8,500 |
| Coal | 2.0 | 2.5 | 11,500 | 8,500 |
| Other | 2.0 | 2.5 | 8,500 | 6,500 |
CN
HP per Ton
CN appears to target 1.0 HP/T for intermodal trains to/from Western Canada - note that CN has a very lightly graded route to both Vancouver and Prince Rupert, in contrast to other transcontinental routes.
CSX
Train Length and Weight
Network-wide restrictions for train length and weight are as follows:
Non-DPU
| Attribute | Intermodal | Manifest | Bulk | Automotive |
|---|---|---|---|---|
| Length (ft) | 12,000 | 10,000 | 10,000 | 10,000 |
| Weight (tons) | 14,000 | 14,000 | 18,000 | 10,000 |
DPU
| Attribute | Intermodal | Manifest | Bulk | Automotive |
|---|---|---|---|---|
| Length (ft) | 14,000 | 12,000 | 12,000 | 14,000 |
| Weight (tons) | 16,000 | 20,000 | 24,000 | 14,000 |
DP units must be no further than 7,000 feet from the head end of the train.
These limits may be further reduced on a local basis by siding infrastructure or other local restrictions, and may be exceeded by specially designated trains or with special approval.
UP
Length
East
Restrictions for train makeup east of Picacho AZ, Cheyenne WY, and Denver CO are as follows:
| Description | Length (ft) | Distance (ft) between DP consists |
|---|---|---|
| Non-DPU | 10,000 | |
| One DPU consist, Intermodal | 15,000 | 10,000 |
| One DPU consist, other | 15,000 | 10,000 |
| Multiple DPU consists | 18,000 (15,000 if no rear DPU) | 6,000 |
| Autorack | 10,000 |
Trains exceeding 60 loaded autoracks must place all autoracks at the rear of the train. Trains exceeding 80 loaded autoracks cannot contain more than 5 non-autorack cars.
West
Restrictions for train makeup west of Picacho AZ, Cheyenne WY, and Denver CO are as follows:
| Description | Length (ft) | Distance (ft) between DP consists |
|---|---|---|
| Non-DPU | 10,000 | |
| One DPU consist, Intermodal | 15,000 | 10,000 |
| One DPU consist, other | 15,000 | 8,500 |
| Multiple DPU consists | 18,000 (15,000 if no rear DPU) | 6,000 between each consist |
| Autorack | 10,000 |
Trains containing 60 or more autoracks are limited to 80 cars.
Weight
West
West of North Platte, Denver, and El Paso, the following trailing tonnage/car placement restrictions apply:
Empty intermodal cars cannot have more than 4,500 tons of weight behind them in the train.
Loaded spine cars cannot have more than 5,500 tons of weight behind them in the train.
Locomotives
Trains are limited in power by equivalent powered axles (EPA). Where multiple mid-train DPU consists exist, each is limited separately. A table of EPA ratings is given underneath the EPA limits table, along with an approximate conversion for six-axle AC locomotives (AC4400CW, ES44AC, ES44AH, SD70MAC, SD70ACe, SD70AH, etc.) in the table itself.
| Description | Head end EPA | Mid train EPA | Rear end EPA | Head end AC locomotives | Mid train AC locomotives | Rear end AC locomotives |
|---|---|---|---|---|---|---|
| Intermodal | 62 | 48 | 24 | 5 | 4 | 2 |
| Manifest | 52 (36 if grade exceeds 1.9%) | 48 | 24 | 4 (3) | 4 | 2 |
| Empty Bulk | 52 (36 if grade exceeds 1.9%) | 36 | 24 | 4 (3) | 3 | 2 |
| Loaded Bulk | 52 (36 if grade exceeds 1.9%) | 55 | 28 | 4 (3) | 4 | 2 |
Local Restrictions
All trains processing over Cajon Pass are limited to 36 EPA.
Equivalent Powered Axle listing
Note that non-UP-owned ES44AC and ES44AH units may not be capable of CTE mode.
| Locomotive | EPA | EPA, 5/6 traction motors | EPA, 4/6 traction motors | EPA, 3/6 traction motors | EPA, remote consist in CTE mode | EPA, remote CTE, 5/6 traction motors | EPA, remote CTE, 4/6 traction motors | EPA, remote CTE, 3/6 traction motors |
|---|---|---|---|---|---|---|---|---|
| C40-8, C40-8W | 7.8 | |||||||
| C41-8, C41-8W | 10.1 | |||||||
| C44-9, C44-9W | 11.5 | |||||||
| ES40DC | 10.1 | |||||||
| ES44DC | 11.5 | |||||||
| SW1500 | 3.7 | |||||||
| MP15 | 4.0 | |||||||
| GP9 | 4.0 | |||||||
| GP15-1 | 3.9 | |||||||
| GP22 | 5.1 | |||||||
| GP38-2 | 4.5 | |||||||
| GP39-2 | 4.5 | |||||||
| GP40-2 | 5.0 | |||||||
| GP50 | 6.5 | |||||||
| GP60 | 8.0 | |||||||
| SD38-2 | 5.4 | |||||||
| SD40-2, SD40N, SD30Eco | 7.1 | |||||||
| SD45 | 7.0 | |||||||
| SD50 | 9.2 | |||||||
| SD59MX | 7.1 | |||||||
| SD60, SD60M | 9.9 | |||||||
| SD70, SD70M | 10.4 | |||||||
| SD75 | 10.3 | |||||||
| C44AC, C44/60AC, C44ACCCA, C6044AC | 12.1 | 11.0 | 8.0 | 6.0 | ||||
| C44ACCTE, C45ACCTE, C45AH, C44ACM, ES44AC, ES44AH | 12.1 | 11.0 | 11.0 | 8.0 | 6.0 | |||
| CW60AC | 12.1 | 12.0 | 11.0 | 8.0 | ||||
| SD70MAC | 10.4 | 6.0 | ||||||
| SD70ACe, SD70AH | 12.0 | 7.0 | 11.0 | |||||
| SD70AH-T4 | 12.0 | 12.0 | 12.0 | 9.0 | 11.0 | |||
| SD9043AC | 11.6 | 7.0 |
Horsepower per Ton
UP expresses train limits as TPA, or Tons per Powered Axle. These can be approximately translated to HP/Ton limits.
| Location | Minimum TPA | Minimum HP/T |
|---|---|---|
| Cascade Subdivision (Eugene OR - Klamath Falls OR) | 170 | 2.1 (summer), 2.4 (winter) |
| Donner Pass, west slope | 165 | 2.2 |
| Tehachapi Pass, west slope | 188 | 1.9 |
Trains over Cajon Pass must meet BNSF HP/T minimums.
