Which railcar is considered obsolete?

• A. Tank car
• B. Boxcar
• C. High pressure tube car
• D. Covered hopper

Answer: (C)

Understanding which railcar designs are still in service helps you see how safety standards have evolved. A high-pressure tube car was an older design used for compressed gases, but its tubular construction creates many potential leak points and weaker protection in crashes or fires. That design doesn’t meet current safety margins and has largely been retired in favor of safer, more robust tank cars and other configurations. The other types—tank cars, boxcars, and covered hoppers—remain in common use because they fit modern loading, unloading, and regulatory requirements for their respective cargoes. So the high-pressure tube car is the one considered obsolete.