The US Transportation Collection consists of documents from across all transportation modes with specific focus on research reports from US DOT, state DOTs, and other transportation organizations.
Bookmark this collection: https://rosap.ntl.bts.gov/collection_ust or https://doi.org/10.21949/1530857.
Severe winter weather poses a significant threat to road users, primarily due to slippery road surfaces, which considerably increase the risk of crashes and injuries. Additionally, such conditions can disrupt traffic flow on highways, causing speed reductions, decreased highway capacity, or even complete traffic lockdowns. Most Departments of Trans
...
Masanja, N. M., Mihayo, M. P., Kidando, E., & Owusu-Danquah, J. (2024). ODOT‘s Snow and Ice Performance Evaluation Tools - A Student Transportation Advancement Research (STAR) Project [Fact Sheet]. Ohio. Department of Transportation. https://rosap.ntl.bts.gov/view/dot/86076
Masanja, Ntemi Methusela, Meshack P Mihayo, Emmanuel Kidando, and Josiah Owusu-Danquah. ODOT‘s Snow and Ice Performance Evaluation Tools - A Student Transportation Advancement Research (STAR) Project [Fact Sheet]. Ohio. Department of Transportation, 2024. https://rosap.ntl.bts.gov/view/dot/86076.
Masanja, Ntemi Methusela, et al. ODOT‘s Snow and Ice Performance Evaluation Tools - A Student Transportation Advancement Research (STAR) Project [Fact Sheet]. Ohio. Department of Transportation, 2024, ROSA P. https://rosap.ntl.bts.gov/view/dot/86076.
The Indiana Department of Transportation (INDOT) manages over 2,000 traffic signals in the State. It is unfeasible to identify systemwide improvement opportunities by evaluating the performance of thousands of traffic signals on monitoring dashboards. This report describes how a scalable technique based on connected vehicle (CV) trajectory data sys
...
Saldivar-Carranza, E. D., Platte, T., Wills, T., Sturdevant, J. R., & Bullock, D. M. (2024). Business Processes to Prioritize Traffic Signal Retiming and Assess the Impact of Retiming Activities (Report No. FHWA/IN/JTRP-2024/33). Purdue University. Joint Transportation Research Program. https://doi.org/10.5703/1288284317807
Saldivar-Carranza, Enrique Daniel, Tom Platte, Terri Wills, James R. Sturdevant, and Darcy M. Bullock. Business Processes to Prioritize Traffic Signal Retiming and Assess the Impact of Retiming Activities. Report no. FHWA/IN/JTRP-2024/33. Purdue University. Joint Transportation Research Program, 2024. https://doi.org/10.5703/1288284317807.
Saldivar-Carranza, Enrique Daniel, et al. Business Processes to Prioritize Traffic Signal Retiming and Assess the Impact of Retiming Activities. Purdue University. Joint Transportation Research Program, 2024, Report no. FHWA/IN/JTRP-2024/33, ROSA P. https://doi.org/10.5703/1288284317807.
During the COVID pandemic, to prevent the spread of the virus, countries adopted various safety measures, including masking, social distancing, and vaccination. However, there is a lack of methods that can quantitively evaluate the effectiveness of these countermeasures. To fill the gap, this research first develops a model to quantitively evaluate
...
Qi, Y., & Zhao, Q. (2024). Countermeasures for Maintaining Safe and Effective Public Transit Service in the Post-COVID-19 Era (Report No. CAMMSE-UNCC-2022-UTC-Project-13). University of North Carolina at Charlotte. Center for Advanced Multimodal Mobility Solutions and Education. https://rosap.ntl.bts.gov/view/dot/77810
Qi, Yi and Qun Zhao. Countermeasures for Maintaining Safe and Effective Public Transit Service in the Post-COVID-19 Era. Report no. CAMMSE-UNCC-2022-UTC-Project-13. University of North Carolina at Charlotte. Center for Advanced Multimodal Mobility Solutions and Education, 2024. https://rosap.ntl.bts.gov/view/dot/77810.
Qi, Yi, and Qun Zhao Countermeasures for Maintaining Safe and Effective Public Transit Service in the Post-COVID-19 Era. University of North Carolina at Charlotte. Center for Advanced Multimodal Mobility Solutions and Education, 2024, Report no. CAMMSE-UNCC-2022-UTC-Project-13, ROSA P. https://rosap.ntl.bts.gov/view/dot/77810.
This report summarizes the impact on corridor-level energy use and emissions associated with the 2018 opening of the I-75 Northwest Corridor (NWC) and I-85 Express Lanes in Atlanta, GA. The research team tracked changes in vehicle throughput on the managed lane corridors (extracted from GDOT’s Georgia NaviGAtor machine vision system after comprehen
...
Lu, H., Liu, H., Guin, A., Rodgers, M. O., & Guensler, R. (2024). Energy and Emissions Impacts of Atlanta’s Reversible Express Toll Lanes and High-Occupancy Toll Lanes (Report No. NCST-GT-RR-24-46). National Center for Sustainable Transportation (NCST) (UTC). https://doi.org/10.7922/G2MP51NM
Lu, Hongyu, Haobing Liu, Angshuman Guin, Michael O. Rodgers, and Randall Guensler. Energy and Emissions Impacts of Atlanta’s Reversible Express Toll Lanes and High-Occupancy Toll Lanes. Report no. NCST-GT-RR-24-46. National Center for Sustainable Transportation (NCST) (UTC), 2024. https://doi.org/10.7922/G2MP51NM.
Lu, Hongyu, et al. Energy and Emissions Impacts of Atlanta’s Reversible Express Toll Lanes and High-Occupancy Toll Lanes. National Center for Sustainable Transportation (NCST) (UTC), 2024, Report no. NCST-GT-RR-24-46, ROSA P. https://doi.org/10.7922/G2MP51NM.
Texas coastal areas are prone to hurricanes, which pose a threat to life, public safety, and critical infrastructure. Mass evacuation can be ordered to relocate residents to safety areas in advance of a hurricane. Access to accurate real-time traffic information can aid public agencies with evacuation operations and evacuees with decision-making. T
...
Bathgate, K., Xu, L., Jiang, K., Sun, J., Robbennolt, J., Pan, S., Han, Z., Murphy, M., Boyles, S., Zhang, Z., & Machemehl, R. (2024). Define a Statewide Plan for a Sustainable Real-Time Travel Time Network for Texas Hurricane Evacuations and Safe Citizen Return – Final Report (Report No. FHWA/TX-24/0-7123-1;0-7123-1). University of Texas at Austin. Center for Transportation Research. https://rosap.ntl.bts.gov/view/dot/77165
Bathgate, Kyle, Lu Xu, Kangni Jiang, Jingran Sun, Jake Robbennolt, Shidong Pan, and Zhe Han, et al.. Define a Statewide Plan for a Sustainable Real-Time Travel Time Network for Texas Hurricane Evacuations and Safe Citizen Return – Final Report. Report no. FHWA/TX-24/0-7123-1;0-7123-1. University of Texas at Austin. Center for Transportation Research, 2024. https://rosap.ntl.bts.gov/view/dot/77165.
Bathgate, Kyle, et al. Define a Statewide Plan for a Sustainable Real-Time Travel Time Network for Texas Hurricane Evacuations and Safe Citizen Return – Final Report. University of Texas at Austin. Center for Transportation Research, 2024, Report no. FHWA/TX-24/0-7123-1;0-7123-1, ROSA P. https://rosap.ntl.bts.gov/view/dot/77165.
Clearly visible lane markings are important for all road users, particularly autonomous vehicles. In general, nighttime retroreflectivity is one of the most challenging marking visibility characteristics for agencies to monitor and maintain, particularly in cold weather climates when agency snowplows remove retroreflective material during winter op
...
Brinster, G. L., Hodaei, M., Eissa, A. M., DeLoach, Z., Bruno, J. E., Habib, A., & Bullock, D. M. (2024). Leveraging LiDAR Intensity to Evaluate Roadway Pavement Marking Retroreflectivity (Report No. FHWA/IN/JTRP-2024/32). Purdue University. Joint Transportation Research Program. https://doi.org/10.5703/1288284317806
Brinster, Gregory L, Mona Hodaei, Aser M Eissa, Zechariah DeLoach, Joseph E Bruno, Ayman Habib, and Darcy M. Bullock. Leveraging LiDAR Intensity to Evaluate Roadway Pavement Marking Retroreflectivity. Report no. FHWA/IN/JTRP-2024/32. Purdue University. Joint Transportation Research Program, 2024. https://doi.org/10.5703/1288284317806.
Brinster, Gregory L, et al. Leveraging LiDAR Intensity to Evaluate Roadway Pavement Marking Retroreflectivity. Purdue University. Joint Transportation Research Program, 2024, Report no. FHWA/IN/JTRP-2024/32, ROSA P. https://doi.org/10.5703/1288284317806.
The iTrain project, in collaboration with the Missouri Department of Transportation (MoDOT), aimed to enhance work zone safety training of MoDOT staff through the development and implementation of virtual reality (VR) training modules. These modules were designed to provide immersive, realistic, and interactive scenarios to enhance knowledge retent
...
Edara, P. K. (2024). iTrain – Immersive Training of Department of Transportation Work Zone Inspectors using Virtual Reality [Research Summary]. Missouri. Department of Transportation. Construction and Materials Division. https://rosap.ntl.bts.gov/view/dot/77706
Edara, Praveen K.. iTrain – Immersive Training of Department of Transportation Work Zone Inspectors using Virtual Reality [Research Summary]. Missouri. Department of Transportation. Construction and Materials Division, 2024. https://rosap.ntl.bts.gov/view/dot/77706.
Edara, Praveen K. iTrain – Immersive Training of Department of Transportation Work Zone Inspectors using Virtual Reality [Research Summary]. Missouri. Department of Transportation. Construction and Materials Division, 2024, ROSA P. https://rosap.ntl.bts.gov/view/dot/77706.
Maintaining the appropriate amount of pavement friction is critical for safe driving. Missouri Department of Transportation (MoDOT) has used high friction surface treatment (HFST) since 2013 to restore pavement surface friction where traffic has worn down pavement surface aggregates and to improve wet crash locations. Conventional HFST application
...
Roshan, A., & Abdelrahman, M. (2024). Friction Enhancements to Asphalt Pavement Surfaces (Report No. cmr 24-015). Missouri. Department of Transportation. Construction and Materials Division. https://rosap.ntl.bts.gov/view/dot/77701
Roshan, Alireza and Magdy Abdelrahman. Friction Enhancements to Asphalt Pavement Surfaces. Report no. cmr 24-015. Missouri. Department of Transportation. Construction and Materials Division, 2024. https://rosap.ntl.bts.gov/view/dot/77701.
Roshan, Alireza, and Magdy Abdelrahman Friction Enhancements to Asphalt Pavement Surfaces. Missouri. Department of Transportation. Construction and Materials Division, 2024, Report no. cmr 24-015, ROSA P. https://rosap.ntl.bts.gov/view/dot/77701.
There is growing recognition that drivers involved in fatal crashes are often engaged in multiple risky behaviors – not wearing a seat belt, speeding, and driving impaired (FARS, 2020). Research has established associations between impulsivity and multiple risky driving behaviors (Bıçaksız & Özkan, 2016b). While the association between impulsivity
...
Supporting Files
Finley, K., Hanson, B., & Green, K. (2024). Resources and Tools to Reduce Multiple Risky Driving Behaviors (Report No. FHWA/MT-24-004/888-444-20). Montana. Department of Transportation. https://doi.org/10.21949/1529562
Finley, Kari, Bridget Hanson, and Kelly Green. Resources and Tools to Reduce Multiple Risky Driving Behaviors. Report no. FHWA/MT-24-004/888-444-20. Montana. Department of Transportation, 2024. https://doi.org/10.21949/1529562.
Finley, Kari, et al. Resources and Tools to Reduce Multiple Risky Driving Behaviors. Montana. Department of Transportation, 2024, Report no. FHWA/MT-24-004/888-444-20, ROSA P. https://doi.org/10.21949/1529562.
The objective of this research was to explore the social and psychological principles that uniquely apply to face-to-face urban transportation systems and apply those to the design of the roadway.
Carver, D., Eluru, N., & Tice, P. (2024). Identifying Mental Frameworks Underlying Driver Behavior in Urban Contexts [Summary] (Report No. BDV24-977-34). Florida. Department of Transportation. Research Center. https://rosap.ntl.bts.gov/view/dot/76687
Carver, DeWayne, Naveen Eluru, and Patricia Tice. Identifying Mental Frameworks Underlying Driver Behavior in Urban Contexts [Summary]. Report no. BDV24-977-34. Florida. Department of Transportation. Research Center, 2024. https://rosap.ntl.bts.gov/view/dot/76687.
Carver, DeWayne, et al. Identifying Mental Frameworks Underlying Driver Behavior in Urban Contexts [Summary]. Florida. Department of Transportation. Research Center, 2024, Report no. BDV24-977-34, ROSA P. https://rosap.ntl.bts.gov/view/dot/76687.
To identify locally available, cost-effective, and durable crushed coarse aggregates for Stone Matrix Asphalt (SMA) and high-level Hot Mix Asphalt (HMA) mixes, multiple well-distributed aggregates have been evaluated in this study as candidate aggregates, including traprock (control), chat, gravels, steel slag, limestone, and dolomite. Aggregate sc
...
Liu, J., Kassem, E., Wang, Y. D., & Lin, B. (2024). Analysis of Asphalt Mixtures Using Alternative Aggregate in SMA and Superpave (Report No. CMR 24-014). Missouri. Department of Transportation. Construction and Materials Division. https://rosap.ntl.bts.gov/view/dot/77703
Liu, Jenny, Emad Kassem, Yizhuang David Wang, and Bo Lin. Analysis of Asphalt Mixtures Using Alternative Aggregate in SMA and Superpave. Report no. CMR 24-014. Missouri. Department of Transportation. Construction and Materials Division, 2024. https://rosap.ntl.bts.gov/view/dot/77703.
Liu, Jenny, et al. Analysis of Asphalt Mixtures Using Alternative Aggregate in SMA and Superpave. Missouri. Department of Transportation. Construction and Materials Division, 2024, Report no. CMR 24-014, ROSA P. https://rosap.ntl.bts.gov/view/dot/77703.
This report presents the development, implementation, and evaluation of Virtual Reality (VR) training modules designed to enhance work zone safety training for the Missouri Department of Transportation (MoDOT) staff. The project aimed to provide immersive, realistic, and interactive training environments that improve knowledge retention, engagement
...
Edara, P. K., Qing, Z., Sun, C., Brown, H., & Balakrishnan, B. (2024). iTrain – Immersive Training of Department of Transportation Work Zone Inspectors using Virtual Reality (Report No. cmr 24-013). Missouri. Department of Transportation. Construction and Materials Division. https://rosap.ntl.bts.gov/view/dot/77705
Edara, Praveen K., Zhu Qing, Carlos Sun, Henry Brown, and Bimal Balakrishnan. iTrain – Immersive Training of Department of Transportation Work Zone Inspectors using Virtual Reality. Report no. cmr 24-013. Missouri. Department of Transportation. Construction and Materials Division, 2024. https://rosap.ntl.bts.gov/view/dot/77705.
Edara, Praveen K., et al. iTrain – Immersive Training of Department of Transportation Work Zone Inspectors using Virtual Reality. Missouri. Department of Transportation. Construction and Materials Division, 2024, Report no. cmr 24-013, ROSA P. https://rosap.ntl.bts.gov/view/dot/77705.
This report investigates the creation and assessment of a decision-making tool developed to aid the Nebraska Department of Transportation (NDOT) in determining the suitability of the Accelerated Bridge Construction (ABC) method for bridge replacement projects. The tool utilizes the Analytic Hierarchy Process (AHP) to integrate different criteria, i
...
Barutha, P., Maguire, M., Saldana, E., & Pozo-Lora, F. F. (2024). Accelerated Bridge Construction (ABC) Decision Tool: Final Report (Report No. SPR-FY22(009);26-1122-0113-001). Nebraska. Department of Transportation. https://rosap.ntl.bts.gov/view/dot/79384
Barutha, Phil, Marc Maguire, Elio Saldana, and Fray F Pozo-Lora. Accelerated Bridge Construction (ABC) Decision Tool: Final Report. Report no. SPR-FY22(009);26-1122-0113-001. Nebraska. Department of Transportation, 2024. https://rosap.ntl.bts.gov/view/dot/79384.
Barutha, Phil, et al. Accelerated Bridge Construction (ABC) Decision Tool: Final Report. Nebraska. Department of Transportation, 2024, Report no. SPR-FY22(009);26-1122-0113-001, ROSA P. https://rosap.ntl.bts.gov/view/dot/79384.
Alkali–silica reaction (ASR), a chemical reaction occurring in concrete between reactive siliceous minerals in some aggregates and alkalis in the concrete pore solution, can produce an expansive gel that, in the presence of sufficient moisture, can lead to expansion and cracking. This not only decreases mechanical properties but also increases perm
...
Kurtis, K. E., Stewart, L. K., & Kumar, D. (2024). Recommendations for Extension in Service Life of ASR-Affected Concrete (Report No. FHWA-GA-24-2018). Georgia. Department of Transportation. Office of Performance-Based Management & Research. https://rosap.ntl.bts.gov/view/dot/77345
Kurtis, Kimberly E, Lauren K Stewart, and Devin Kumar. Recommendations for Extension in Service Life of ASR-Affected Concrete. Report no. FHWA-GA-24-2018. Georgia. Department of Transportation. Office of Performance-Based Management & Research, 2024. https://rosap.ntl.bts.gov/view/dot/77345.
Kurtis, Kimberly E, et al. Recommendations for Extension in Service Life of ASR-Affected Concrete. Georgia. Department of Transportation. Office of Performance-Based Management & Research, 2024, Report no. FHWA-GA-24-2018, ROSA P. https://rosap.ntl.bts.gov/view/dot/77345.
Minimizing pavement impact on wet weather crashes is essential to the Wet Surface Crash Reduction Program (WSCRP). Currently, the Texas Department of Transportation has two methods to evaluate pavement friction: the Safer by Design (SBD) method and the pavement surface aggregate classification selection, Form 2088. The research team developed a fra
...
Wu, L., Nyamuhokya, T., & Park, E. S. (2024). Develop Safety Scoring Tool for the Wet Surface Crash Reduction Program [Project Summary] (Report No. 0-7142). Texas. Department of Transportation. https://rosap.ntl.bts.gov/view/dot/78978
Wu, Lingtao, Tito Nyamuhokya, and Eun Sug Park. Develop Safety Scoring Tool for the Wet Surface Crash Reduction Program [Project Summary]. Report no. 0-7142. Texas. Department of Transportation, 2024. https://rosap.ntl.bts.gov/view/dot/78978.
Wu, Lingtao, et al. Develop Safety Scoring Tool for the Wet Surface Crash Reduction Program [Project Summary]. Texas. Department of Transportation, 2024, Report no. 0-7142, ROSA P. https://rosap.ntl.bts.gov/view/dot/78978.
After being in service for nearly 20 years, the Illinois Accelerated Pavement Tester (I-APT) was upgraded to provide enhanced capabilities for accelerated pavement testing. In addition to a new control system, the improvement included a newly designed load carriage, which allows for testing with a tandem half-axle, axle yaw, and shear loading (brea
...
Renshaw, G., Al-Qadi, I. L., & Kohler, E. R. (2024). Enhanced Capabilities of the Illinois Accelerated Pavement Tester (Report No. FHWA-ICT-24-017;ICT-24-020;UILU-2024-2020). Illinois Center for Transportation. https://doi.org/10.36501/0197-9191/24-020
Renshaw, Greg, Imad L. Al-Qadi, and Erwin R Kohler. Enhanced Capabilities of the Illinois Accelerated Pavement Tester. Report no. FHWA-ICT-24-017;ICT-24-020;UILU-2024-2020. Illinois Center for Transportation, 2024. https://doi.org/10.36501/0197-9191/24-020.
Renshaw, Greg, et al. Enhanced Capabilities of the Illinois Accelerated Pavement Tester. Illinois Center for Transportation, 2024, Report no. FHWA-ICT-24-017;ICT-24-020;UILU-2024-2020, ROSA P. https://doi.org/10.36501/0197-9191/24-020.
The design of J-turn intersections has gained its prevalence in Missouri due to their demonstrated safety benefits. However, with the growing number of J-turns and the availability of more crash data, there is a renewed need to deepen the understanding of the safety performance of J-turns. This study presents a comprehensive safety evaluation of J-
...
Edara, P., Qing, Z., Brown, H., Sun, C., & Baek, H. J. (2024). Safety Evaluation of J-turn Intersections in Missouri (Report No. cmr 24-011). Missouri. Department of Transportation. Construction and Materials Division. https://rosap.ntl.bts.gov/view/dot/77597
Edara, Praveen, Zhu Qing, Henry Brown, Carlos Sun, and Ho Jun Baek. Safety Evaluation of J-turn Intersections in Missouri. Report no. cmr 24-011. Missouri. Department of Transportation. Construction and Materials Division, 2024. https://rosap.ntl.bts.gov/view/dot/77597.
Edara, Praveen, et al. Safety Evaluation of J-turn Intersections in Missouri. Missouri. Department of Transportation. Construction and Materials Division, 2024, Report no. cmr 24-011, ROSA P. https://rosap.ntl.bts.gov/view/dot/77597.
Crashes related to barrier end treatments and impact attenuators generally have higher severity levels than those colliding with barrier faces. To select the most effective end treatments, the in-service safety evaluation of such end treatments under various operational conditions was needed. This study linked 7 years of crash records with the corr
...
Tarko, A. P., & Romero, M. A. (2024). In-Service Safety Evaluation of Indiana Impact Attenuators and Barrier End Treatments [Summary]. Purdue University. Joint Transportation Research Program. https://rosap.ntl.bts.gov/view/dot/80367
Tarko, Andrew P. and Mario A. Romero. In-Service Safety Evaluation of Indiana Impact Attenuators and Barrier End Treatments [Summary]. Purdue University. Joint Transportation Research Program, 2024. https://rosap.ntl.bts.gov/view/dot/80367.
Tarko, Andrew P., and Mario A. Romero In-Service Safety Evaluation of Indiana Impact Attenuators and Barrier End Treatments [Summary]. Purdue University. Joint Transportation Research Program, 2024, ROSA P. https://rosap.ntl.bts.gov/view/dot/80367.
The raw data includes one excel file (418 KB) covering measurements including time, temperature, frequency, phase angle, complex modulus, elastic modulus, viscous modulus, complex viscosity, shear stress, and strain.
DatasetSupporting Files
Abdallah, I., Montoya, M. A., & Mohajeri, Z. (2024). Investigation of Hot Mix Asphalt Aging Effect on Mechanical Properties of Mixes Based on Their Binder Performance Results [supporting dataset]. The Southern Plains Transportation Center (SPTC) Region 6 University Transportation Center (UTC). https://rosap.ntl.bts.gov/view/dot/88342
Abdallah, Imad, Miguel A. Montoya, and Zahra Mohajeri. Investigation of Hot Mix Asphalt Aging Effect on Mechanical Properties of Mixes Based on Their Binder Performance Results [supporting dataset]. The Southern Plains Transportation Center (SPTC) Region 6 University Transportation Center (UTC), 2024. https://rosap.ntl.bts.gov/view/dot/88342.
Abdallah, Imad, et al. Investigation of Hot Mix Asphalt Aging Effect on Mechanical Properties of Mixes Based on Their Binder Performance Results [supporting dataset]. The Southern Plains Transportation Center (SPTC) Region 6 University Transportation Center (UTC), 2024, ROSA P. https://rosap.ntl.bts.gov/view/dot/88342.
Motorcyclists are among the most vulnerable users of the roadway system. The appropriate design of roadside safety systems plays an important role in the severity of injuries caused by motorcycle crashes. Data show that from 2004 to 2017, the number of fatalities related to motorcycle impacts against safety barriers was greater than the number of f
...
Schulz, N. D., Bligh, R. P., Dadashova, B., Dobrovolny, C. S., & Schroeder, W. J. L. (2024). Develop a Retrofit Design for Guard Fence System To Enhance Motorcycle Safety (Report No. FHWA/TX-23/0-6994-R1). Texas A&M Transportation Institute. https://rosap.ntl.bts.gov/view/dot/77975
Schulz, Nathan D., Roger P. Bligh, Bahar Dadashova, Chiara Silvestri Dobrovolny, and William J. L Schroeder. Develop a Retrofit Design for Guard Fence System To Enhance Motorcycle Safety. Report no. FHWA/TX-23/0-6994-R1. Texas A&M Transportation Institute, 2024. https://rosap.ntl.bts.gov/view/dot/77975.
Schulz, Nathan D., et al. Develop a Retrofit Design for Guard Fence System To Enhance Motorcycle Safety. Texas A&M Transportation Institute, 2024, Report no. FHWA/TX-23/0-6994-R1, ROSA P. https://rosap.ntl.bts.gov/view/dot/77975.
Links with this icon indicate that you are leaving a Bureau of Transportation
Statistics (BTS)/National Transportation Library (NTL)
Web-based service.
Thank you for visiting.
You are about to access a non-government link outside of
the U.S. Department of Transportation's National
Transportation Library.
Please note: While links to Web sites outside of DOT are
offered for your convenience, when you exit DOT Web sites,
Federal privacy policy and Section 508 of the Rehabilitation
Act (accessibility requirements) no longer apply. In
addition, DOT does not attest to the accuracy, relevance,
timeliness or completeness of information provided by linked
sites. Linking to a Web site does not constitute an
endorsement by DOT of the sponsors of the site or the
products presented on the site. For more information, please
view DOT's Web site linking policy.
To get back to the page you were previously viewing, click
your Cancel button.