TTC OPERATED BY ENSCO, RAILWAY AGE APRIL 2025 ISSUE: Every day, trains collide with people or vehicles an average of eight times across the U.S. According to the Federal Railroad Administration (FRA), incidents at grade crossings and trespassing account for 96% of rail-related fatalities. For these reasons, improving grade crossing safety is a top priority for communities, railroads and government agencies [1].
At the Transportation Technology Center (TTC) in Pueblo, Colo., researchers are working to reduce these risks through full-scale grade crossing collision testing. TTC is one of the few places in the country where real-life crash scenarios can be safely recreated, providing valuable data to improve rail safety.
Real-World Crash Testing
In the early 2000s, TTC conducted several full-scale crash tests to study how different vehicles and rail equipment withstand high-impact collisions at grade crossings. These tests helped engineers design safer locomotives, improve computer simulation models and better understand crash dynamics.
The first test involved a three-car consist led by an SD-45 locomotive, modified to meet Association of American Railroads (AAR) Specification S-580, impacting a stationary log truck at a grade crossing at 50.4 mph. The impact caused significant damage to the sheet steel covering the locomotive’s short hood, but the locomotive broke through the logs and continued down the track without derailing. The anti-climber and collision posts of the locomotive remained undamaged. All the logs were broken in two, and the rear axles of the log trailer were thrown clear of both the roadway and the railway track. The locomotive’s fuel tank struck the frame extension of the tractor-trailer, bending it by approximately six inches at the end. The rear axle of the tractor slid about six feet along the railway track, while the front axle remained in its original position. Despite the impact, the semi-truck remained upright throughout the collision [2].
The second full-scale impact test involved a locomotive crashing into a highway tractor and trailer loaded with two steel coils. This test was conducted at a grade crossing at the TTC on Dec. 18, 2002. The rear steel coil was aligned with the locomotive’s right-side collision post. An anthropomorphic test device (ATD) was seated on the floor in the nose of the locomotive. The impact occurred at approximately 58 mph. Upon impact, the trucking rig was thrown clear of the track and destroyed. The chains securing the coils to the trailer broke, causing the rear coil to strike the collision post, shearing it just above the weld connecting it to the underframe. The coil then continued into the cab, destroying the windshield, control console, and cab floor. The ATD sustained severe damage, including injuries to the head, neck, left shoulder attachment and skin [3].
Similar grade crossing tests were conducted using passenger rail equipment. In two tests, a cab car traveling on tangent (straight) tracks collided at an angle with a 41,300-pound steel coil, which was raised about four feet above the top of the rail, at a speed of approximately 14 mph. The first test featured a cab car built to pre-1999 safety standards, while the second test used a cab car designed to meet modern requirements. The goal was to compare the crashworthiness performance of the older and newer corner post designs and to validate computer models developed to simulate the structural and dynamic conditions.
One of the more spectacular tests conducted at the TTC involved a full-scale grade crossing collision between an LNG (liquefied natural gas) tender and an 80,000-pound truck at 40 mph, replicating a scenario outlined in AAR M-1004 safety guidelines. As a result of the impact, the track structure supporting the tender and locomotives experienced tie shift and rail rollover, resulting in the derailment of both tender trucks and one truck of each locomotive. However, no puncture or damage resulting in the commodity release occurred. Additionally, the safety shutoff valve successfully activated, cutting off the fuel supply of the locomotives, demonstrating that even under extreme impact conditions, the fuel tenders remained secure.
Public Awareness Demo
Beyond controlled research tests, TTC also conducts public safety demonstrations to highlight the risks of grade crossing collisions. In the past year, ENSCO conducted two full-scale grade crossing impact demonstrations. The first involved a locomotive colliding with a parked bus at 35 mph—simulating a real-life scenario where a stranded vehicle is struck at a crossing. The bus sustained severe damage, but the locomotive remained on track.
The second demonstration involved a locomotive hitting a highway tanker trailer, demonstrating what happens when a large truck gets stuck on a high-profile crossing. This demonstration was part of the 2nd Annual TTC Conference held in October 2024. Upon impact, the tanker was pushed off the road, rolled over in the dirt and came to rest beside the track. The locomotive did not derail, and no significant damage to the locomotive or track was observed. This demonstration also highlighted the use of in-situ high-speed video collection for video analytics and measurements [4].
Safer Grade Crossings
Looking ahead, TTC is expanding its role in multimodal transportation safety. The upcoming Grade Crossing (GX) Testbed will serve as a research hub where cross-modal transportation safety challenges can be addressed in a controlled environment.
Unlike real-world scenarios, where regulatory and safety concerns limit testing, the GX Testbed will allow for hands-on experiments including 1) engineering solutions to prevent collisions; 2) human-factor studies to understand driver and pedestrian behavior; and 3) training programs for emergency responders.
By creating a safe and flexible space for cross-modal testing, the GX Testbed will play a key role in advancing rail and road safety nationwide.
Conclusion
Grade crossing safety is a major public concern, but through cutting-edge research and full-scale testing, TTC is helping reduce risks and improve safety measures for both rail passengers and roadway users. By combining past crash data, real-world testing, and new research initiatives, TTC continues to lead the way in making transportation safer for all.
To learn more about the TTC and full-scale testing, visit ttc-ensco.com.
References
[1] www.railroads.dot.gov.
[2] Russell Walker, Barrie Brickie “Locomotive Crashworthiness Impact Test No. 3: Test Procedures, Instrumentation, and Data,” Report No. DTFR53-93-C-00001, February 2003.
[3] Russell Walker “Locomotive Crashworthiness Impact Test No. 2: Test Procedures, Instrumentation, and Data,” Report No. DTFR53-93-C-00001, February 2003.
[4] Karina Jacobsen, David Tyrell “Railcar Impact Tests with Steel Coil: Collision Dynamics,” Proceedings of ASME/IEEE Joint Railroad Conference, JRC2003-1655, April 22-24, 2003.
