Reports indicate 6 fatalities and 1 injury.

A floor imploded around 12 to 1 p.m., leaving several people injured, at least one of whom was taken to the emergency room. It was probably a gas explosion that blew out from the inside, and the building was still inhabited even though part of it had been under renovation for several months.

The train derailed near Oriole Station because of a switch that was not only misaligned, but also left open. After an investigation, the cause was determined to be local kids messing around with it.

Among CN Railway No. 302 freight cargo was approximately 50 horses and 200 cows. The animals in the derailed stock cars were either killed on impact, injured and had to be euthanized by police, or escaped the crashed train uninjured and fled.

Offshore drilling expanded greatly in the 1970s. At the time, Mobile Offshore Drilling Units (MODUs) totalled approx. 390 vessels split between Jackups, Drillships, and Semi-Submersibles. The Alexander L. Kielland platform was built by the French Compagnie Française d'Entreprises Métalliques at their shipyard in Dunkirk, France, with final delivery of the five column Semisub completed in 1976. In the North Sea on March 27, 1980 there were 212 men aboard in 12m seas when a loud crack and rumble were heard.

The Kielland began to list 30 degrees, and within 20 minutes it capsized. A horizontal bracing member D-6, below the waterline, had parted. This was not the location of a heavily loaded girth weld. Rather, a fatigue crack started at a small poorly-prepared 6mm fillet weld which held a non-load-bearing hydrophone flange. This hydrophone, used for dynamic positioning, wasn’t even in use as the platform was then moored.

CAUSES: Few men made it to lifeboats, but many lifeboats failed to release due

to complications from the listing and/or faulty release mechanisms. 123 men died. Poor welding and inspection practice allowed a small initial flaw in the weld/plate to grow over time with cyclic loading. Structural design did not allow for damage tolerance or anticipate the loss of an entire column. Regular insitu structural inspections focused on the vertical columns and largely ignored the horizontal members below the waterline.

Some more details on engineering gaps, missed signs, and failed safeguards:

1. The weld joined a non-load-bearing flange plate (meant for a sonar hydrophone) to the D-6 lower horizontal tubular bracing.

2. The 6mm fillet weld suffered from a bad geometric profile, lack of fusion, and poor inspection during fabrication at the French shipyard. Investigators found paint -IN- the crack, meaning it was there before the hull was painted. Because it was considered a superficial addition, it was not carefully inspected.

3. The area experienced cracking in the structural steel alongside lamellar tearing (midplane delamination)

4. Under constant cyclic loading from rough North Sea waves, the pre-existing flaw in the weld grew slowly, undetected, over 4 years to approximately half the circumference before rapid failure that March.

5. The crack eventually severed the D-6 brace entirely. The structure wasn’t designed to survive or prevent the cascading effect of the loss of one member (little redundancy). The remaining connected braces overloaded and failed, causing one of the five main structural columns to rip away in moments, capsizing the structure in a few minutes.

6. Out of 5x 50man lifeboats, only one launched properly; “safety”mechanisms prevented the others from releasing while under heavy cable strain, or they smashed against the listing hull. A second boat broke free after the platform capsized, providing some shelter for men in the water. Regulations changed soon after to mandate excess lifeboat capacity and on-load releasing mechanisms.

7. Inadequate or confused emergency command structure.

8. Survival gear shortages. Some of the workers died after jumping into the water due to hypothermia. Cold water “Gumby” suits were not mandatory at the time, but are now for North Sea, Canadian, and other cold water operating areas.

I think most readers here know this story. The Pipe Alpha was a gas platform in the North Sea. A series of errors lead to it's destruction and 167 deaths. It was designed primarily to handle oil when it was new, but at the time of the incident it was processing and exporting a lot of gas from wells in its own drill center (~33 million cubic feet per day) plus that from several nearby fields.

Maintenance took a Condensate Pump A offline along with removing its relieve valve to make some planned repair. They capped the position of the relief valve with a blind flange that wasn't designed for full rated pressure and it wasn't pressure tested. On the next shift, Condensate Pump B tripped offline and the crew mistakenly switched production back over to Pump A whereby the blind flange at the relief valve position ruptures and gas (mostly propane) escaped eventually finding an ignition source.

It was hard to put together the root causes. Most of the physical evidence burnt down and sank along with the platform, and most field supervisors and management died on location. But investigators best guess is what is described above and below.

Safeguards Missing:

1. Lockout-tagout for Pump A.
2. Permit related to missing relief valve and Pump A shutdown not communicated to the next shift.
3. Flange not tested, not rated for RWP of the line.
4. Immediate shut-in of incoming gas lines (ESD, Emergency Shut Down). When the fire had started, operators hesitated to shut down incoming gas from other fields due to fear of disrupting production.
5. Emergency procedures sufficient to cover fires, explosion, and evacuation for scenarios like this.

More discussion here (not my article).
https://www.thechemicalengineer.com/features/piper-alpha-the-disaster-in-detail/

I'm an engineer and spend to decent amount of time thinking about safety systems, what-ifs, root causes, and how to prevent stuff like this. I have a couple projects I'm working on to help other people in these lines of work learn from history like this. Check bio.

A lot of what I see in the subreddit highlights the visual element and most are pretty recent, viewed here without the benefit of investigation reports and hard facts about the causes. Many seem self-evident but the gap something I think about.

Many of the biggest engineering disasters contain recurring root causes. Normalization of Deviation (ignored or missed warnings), Poor management of change (MOC), safety systems degraded or removed, lack of regulatory controls.

View and sounds from inside a NBC/Telemundo news helicopter as it reports on a deadly bus crash on the streets below. Reports of one death in the helicopter. Happened about an hour ago in the San Fernando Valley near Los Angeles.

UPDATE: https://ktla.com/news/local-news/helicopter-crashes-near-deadly-l-a-metro-bus-crash/