> "Professor, let me understand this," Loge said. "You are talking about having 800 people wearing orange vests, sitting on camping stools, holding thermoses filled with coffee, and shouting into their cell phones, 'Open the fire door'?" Loge refused the airport an operating license. Schwarz stood up and walked out without another word.
Yeah, some politician got some "duh, stupid engineers" points out of that sentence. Completely ignoring the fact that the original design also pulled smoke down and was considered to be fine. Since these systems are active and suck the smoke out up or down doesn't matter all that much.
From the third paragraph: "Smoke evacuation canals designed to suck out smoke and replace it with fresh air failed to do either. In an actual fire, the inspectors determined, the main smoke vent might well implode." Assuming the inspectors were correct, the original design, at least as implemented, didn't work.
While the "in accordance with the laws of physics" may be overly catty, a bit of searching around suggests that smoke evacuation dampers are generally placed on the ceiling, and it's not unreasonable to think that's because, well, smoke rises, isn't it?
AFAIK the smoke was pulled in at the ceiling of the floors. And then sent downwards and vented out somewhere on the side instead of on top of the building.
The original design was never tested, because the building as originally designed never existed.
Each addition ordered up by Schwarz required shifting passenger flows through the terminal. That meant rebuilding walls, exits, emergency lights, ventilation systems, windows, elevators, and staircases. At one point, in 2009, outside controllers urged Schwarz and his engineering chief to shut down construction for half a year to give the architects and contractors time to coordinate efforts.
That never happened, so there never was a complete design for the changed building, and the fire system wasn't properly replanned for the new situation. Which lead to issues like the collapsing pipes: They fitted stronger fans, but no-one realized that the pipes can't hold the higher pressure difference.
IDKSAS, but wouldn't a system like this (electrically powered venting) be prone to failure in an actual fire? If power fails with side/down venting, the smoke would have no where to go.
Yes it would. My assumption is that they were planning on it only needing to hold out long enough to evacuate everyone. Still, it's indeed the better design to fail safely, and still let some smoke waft out the chimneys, than the actual fail mode, which is to burst into shrapnel.
It does sound like a situation where "excessive cleverness" is being applied to an engineering problem, where a simple/robust/passive/failsafe solution may be available.
Having owned several German sports cars, I must say that "excessive cleverness" just might be a German trademark. When compared to the Corvette, the only American sports car I had, excessive, and largely unnecessary cleverness is very much prevalent in german designs.
>> "You are talking about having 800 people wearing orange vests, sitting on camping stools, holding thermoses filled with coffee, and shouting into their cell phones, 'Open the fire door'?"
Funny thing is, if they had allowed that there would never be an opportunity to fix it correctly. It would require shutting down the airport for quite some time.
The parallels with software and other areas of engineering are a bit disturbing.
Easily the best part of the article.