Annotation page

FRA regulations and safety concept

The Federal Railroad Administration seems to rely on strong, heavy carbodies for passenger safety. This is an amazing concept for several reasons:

  1. Best practice, regarding the safety of passenger railroad operation, is shown by Japanese companies. Some of them outperform any airline in safety, by a huge margin, and they do this with the lightest trains on the planet, lighter than USA streetcars or LRVs.
  2. For decades, the USA have pioneered those safety features, that are used by railroads in Europe or Japan today. The Interstate Commerce Commission (ICC) began pushing for Automatic Train Control and cab signaling nearly 100 years ago, and in 1922, issued an order, that required the first installations.
  3. In the late 1940s, safety improvements by cab signaling or Automatic Train Stop were still considered important enough, for trying to armstrong the railroads into usage on trunk routes by the 79mph rule. (US railroads may not operate at >79 mph without such signaling improvements.)

Cab signaling device in an E unit
European or Japanese readers need to note, that US cab signaling is just that: A signal in the cab. Its first generation was a contemporary development to the French Crocodile and the German Indusi. In the 1920s and a long time thereafter, the USA cab signaling has set the standard for best practice.

The approach towards safety shifted in the 1950s, when the railroads started their transformation into freight railroads. In those years, huge public investments went into the road system, but the railroads would have had to pay for the signaling upgrades on their own. Instead of giving in to the ICC rule, they gave up to compete for passenger traffic, slowed the trains down to 79 mph, and this way, avoided to compete with additional infrastructure costs against the deep pockets of the taxpayers.

Taking the view of the industry, today's US approach to safety - no automatic train stop systems, but heavier coaches - has considerable advantages:

  1. Additional signal requirements cause additional infrastructure costs, and add cost to any freight locomotive. Freight trains are already safer than trucking, and it does not make sense to punish the safer mode with additional requirements. While trucks operate on public infrastructure, the railroads would have to pay the full costs of the upgrade. In contrast, providing high strength with a 200 ton freight loco, that is designed to pull 20000 ton trains, is almost for free.
  2. The additional carbody strength is very costly for passenger railroads, as soon as these want to achieve a competitive average speed. But passenger railroads are subsidized in the USA, with much higher amounts per train mile than in Europe. In the view of an industry, which is a freight business plus just a tiny bit of passenger traffic, concentrating additional costs on the subsidized operations is a good idea.
  3. Thanks to the low density of traffic, the net result in passenger safety is comparable to safety results of European railroads. The risk of vehicle-vehicle crashes is a function of the number of conflicts, in any mode of transport, and this number is much lower in the US network with its long, heavy freighttrains, operating in low density. As an exercise for the reader, I recommend to calculate the number of siding meets on singletrack in 24 hours, if 300000 tons of freight, 150000 per direction, are transported by
    • US-style 15000 ton trains.
    • 10000 ton trains
    • 5000 ton trains
    • 2500 ton trains
    • 1250 ton trains
    • 625 ton trains
    While the operation of very long trains has been chosen for economic reasons, this decision also reduces the number of conflicts to a minimum, and is the central safety feature of the US network.
  4. Safety of railroad operation depends on the quality of the ruleset and the strictness of its enforcement, on crew training, on law enforcement at grade crossings, and on the signaling system with its built-in safety features. None of these issues is easily explained to journalists or politicians. In contrast, the concept of "passive safety by weight" is familiar to many cardrivers, and easy to communicate. Even if its effectiveness might score low in a thorough risk assessment study, it is therefore well suited, to avoid other measures with higher costs to the freight railroads.

One function of the safety authority FRA is: To promote the industry. While this might sound irritating, the FRA shouldn't get the blame for it: Its responsibilities were set up by political decision. If the decisions of the FRA shift costs from the industry in general to its tiny subsidized passenger section, this is in line with the tasks given to this agency.

The consequences for passenger rail

  1. High-speed rail is unfeasible under FRA regulation. Precision requirements for the track rise sharply with speed, raising maintenance costs to unacceptable levels, unless the problem is counterbalanced by lower axleload. More than 19 tons of axleload are unacceptable in high-speed service. While the Japanese and French did it right from the beginning, the Germans learned it the hard way, and have since lowered the weight of ICE trains by a major amount. Accomodating the weight of FRA-legal trains within 19 tons might be technically possible, but needs a new one-of-kind design with a very high number of wheels. More than twice the costs per seat have to be expected, in comparison to off-the-shelf high-speed trains.
  2. Active tilting trains are unfeasible, at least if supposed to operate at tilting train speed. Running fast through curves with steel wheels on steel rails creates tremendous forces at the wheels, making axleload the most safety critical value. At 11.8 inches of cant deficiency, as used in several European countries, FRA-legal trains are beyond the limits of safe operation. Thanks to their construction's inherent strength, Talgos are the best solution for US conditions at the moment, offering 9 inches of cant deficiency at least.
  3. Lowfloor level boarding, compatible with freight, is unfeasible with normal rail vehicles rolling on bogies. The unavoidable stress risers at the transition from low floor to the second level above the bogies cause too much weight gain at FRA strength level. If a highfloor car gains 10 tons within FRA jurisdiction, such car would easily gain more than 20 tons of fat.
  4. Sufficient door capacity for urban transit is impossible under FRA regulation, because several big holes in the structure and FRA strength requirements don't mix. This means about double the dwell time, in comparison to separated heavy rail systems regulated by the FTA.
  5. Modern urban rail transit, serving many stops at high average speed, is unfeasible, due to the dwell time, and because the overweight trains accelerate too slowly.
  6. Small-scale rail transit is unfeasible, because the incremental costs of such train service may not be much higher than for a bus. This is impossible with the obese vehicles prescribed by the FRA, and their high fuel consumption figures. As well, there is not enough speed gain over bus systems.
  7. After most elements of modern passenger rail have been regulated out of feasibility this way, the brightest heads will look for jobs in other industries.

Unit conversion for text on this page.
79 mph 127 km/h  
200 tons 181437 kg  
20000 tons 18144 metric tons  
300000 tons 272155 metric tons  
150000 tons 136078 metric tons  
15000 tons 13608 metric tons  
10000 tons 9072 metric tons  
5000 tons 4536 metric tons  
2500 tons 2268 metric tons  
1250 tons 1134 metric tons  
625 tons 567 metric tons  
19 tons 17237 kg  
11.8 inches of cant deficiency 300 mm of cant deficiency 2 m/s2 unbalanced lateral acceleration
9 inches of cant deficiency 229 mm of cant deficiency 1.51 m/s2 unbalanced lateral acceleration
10 tons 9072 kg  
20 tons 18144 kg  

about this document            Hans-Joachim Zierke            © notice            Thank you

Page posted: 2003-11-04        Last modified: 2005-10-23