Failure Files

In May 2026, GM recalled 2,464 full-size SUVs — Escalades, Tahoes, Suburbans, and Yukons — because dealers had been installing the wrong wheel hub bolts on vehicles with 24-inch wheels. The NHTSA filing confirmed the root cause: the parts catalog didn't distinguish between wheel sizes. Here's what the physics of a bigger wheel have to do with bolt selection.

In 1985, a concrete ceiling collapsed onto a swimming pool in Uster, Switzerland, killing 12 people. The confirmed cause: the wrong grade of stainless steel — V2A (Type 304) without molybdenum — was used for load-bearing suspension rods in a chloride-rich pool environment, leading to silent, catastrophic stress corrosion cracking.

On April 22, 2021, one undertorqued connecting rod bolt destroyed a Washington State Ferry's diesel engine, started a fire, and caused $3.8 million in damage. The NTSB's confirmed finding is a masterclass in why torque specifications aren't suggestions.

On January 5, 2024, a Boeing 737 MAX 9 door plug blew out mid-flight because four retention bolts were never reinstalled after a factory rework procedure. The NTSB published its final report in June 2025. Here is what every maintenance professional and fleet manager should take away from this incident.

In 2013, 32 anchor bolts on the newly opened San Francisco-Oakland Bay Bridge snapped — despite meeting every spec they were given. Here's what hydrogen embrittlement, sustained load, and saltwater exposure taught the engineering world about fastener selection and the environment.

On July 17, 1981, two elevated walkways collapsed at the Hyatt Regency Hotel in Kansas City, killing 114 people. The cause traces back to a single design change involving threaded rods — and a load that nobody recalculated. Here's what it still teaches us about fastener selection today.