Why did Asiana flight 214, packed with passengers, suddenly crash land and cartwheel across San Francisco International Airport’s runway? Three families of the dead want answers. And, what triggered a massive explosion at a chemical plant outside Wichita, Kansas? Chemical engineers and investigators hunt for clues, and find the same danger exists throughout the entire country. Then, dangerous sinkholes exist in 20 percent of the United States. Isn’t there anything that geotechnical engineers can do to protect property and lives? Also, next time you’re on a cruise vacation, it helps to know what could go wrong, based on a disastrous fire at sea on the Carnival Triumph. But can mega-ship engineering be fixed to avoid another cruise from hell? Finally, throughout the country, crucial infrastructure is falling apart. A mega-tunnel in Seattle is just one of the big fixes, but how can engineers finish their work when the world’s largest tunneling tool is stuck underground?