That's actually not too bad. Though I must say the pencil sketches look a lot better than the more polished CGI.

I think it's too busy, esp. at night. The "space between" at ground level seems like it would be lost in shadow -- instead of two simple towers, you're replacing it with three complex ones.

It works great from overhead -- but the people in the city don't see it from there.

My gut feeling? Give Skidmore Owen Merrill (SOM) the project, and tell them to go for the skies. But that's Chicago talking.

A really nice idea, but as Erik suggests I think the ground-level parks would simply be overwhelmed. Dark little grottos.
The whole What To Put There question is incredibly tough and intriguing. The same towers? No way. Timid mid-sized towers? Nah.

I like the direction of the design published in the New York Times Magazine. Towers, yes, but gently twisted and vaguely organic. A ramp running from the Battery to a memorial site. A lattice-ish transmission tower that happens to be the world's tallest structure.

Either that, or build the Brain Pan building from _Metropolis_.

It does work best with the sketched-in ghosts of the original towers there to make it clear what's going on.

I think it could still work if the new towers were transparent enough, but American office plans (and the air-conditioning costs) would probably nix that.

It would be nice if a massive new structure in lower Manhattan could be reasonably energy efficient and lead the way to what Bill Clinton referred to as "simplifying decisions" about American relations with oil-rich nations that are supporters of terrorism. (Observed on the Letterman show on the evening of 9/11/2002.)

Having spent some time visiting in the WTC in the early 1980s, I also have to hope that whatever replaces it will be much more to human scale, easier to clean, and provided with significantly more "overhead" space for health and safety requirements than the old buildings.

Is there some way of seeing this thing that doesn't involve at least 13 megs of download?

There are some drawings at the CNN site.

Sorry, Avram. I tried freezing the animation and doing screen snaps (on a PC), and learned something interesting and not at all useful about screen snaps from Flash animation. Maybe someone more technically knowledgeable could do the same, and capture the five or six frames out of that long presentation that convey an idea of how it looks.

Much of what they have in the MPEG is nothing more than the words that preceded the link, slowly and lingeringly fading in and out. If they wanted to just show the proposal, they could do it with a handful of small JPEGs.

I like the idea of negative space memorials. I thought of submitting one when they had a contest here for a memorial arch, years ago. Negative sculptures inside the arch would have the illusionistic effect of seeming to turn their heads to keep facing the observer.

My favorite part of the presentation is the use of the theme from THE PIANO. But really, looking at the footprint, there is no reason whatsoever for the "space between" memorial parks to be dark or shadowy spaces. The gaps between the buildings are *huge*, and if the axis of orientation running between opposite gaps is East-West, then the space between the buildings should open South and North. South is significant because that's where the arc of the sun should lie, casting light into that space for most of the day. What you don't want is one of the towers on the south side of each space. That *would* be dark.

They're nothing like so tall, but there's a set of hotels in San Diego, near the convention center, whose footprints define a broken ring, and there isn't anything dark in feeling or fact about the space in the middle. I don't see that as a problem, here. And I really like the idea of the footprint of the original buildings not being built upon, but left as a memorial park.

But, really, I'm not a New Yorker, so I'm not sure my opinion matters that much.

South is significant because that's where the arc of the sun should lie, casting light into that space for most of the day. What you don't want is one of the towers on the south side of each space. That *would* be dark.

There's a large collection of buildings to the South-east, a couple tall (20+ floors) due south, and 1 WFC to the South West -- the only really clear lane to the South is along a major road/highway.

The only real light you have at the WTC site is from above. This is one reason the WFC works better that WTC did -- it gets a clear shot from the west, and it's not nearly as dense, so light gets in.

I like it too. Te idea of negative space is perfectly appropiate.

If buildings south of the structure really block that much light, use mirrors. It worked for the Egyptians, so I have to think this is a solved problem.

"If buildings south of the structure really block that much light, use mirrors. It worked for the Egyptians, so I have to think this is a solved problem."

I think this is a different problem; I'd be concerned about glare (one wouldn't want to reflect direct sunlight into someone's window), and the quality of the light in the central spaces.

But response to that issue might take the surrounding buildings from "architectural greeking" to material objects.

Randolph, since you're an architecture dude and all, are there any changes in the design of large buildings to accommodate the fact that every crazy son of a bitch in the world now has the idea of flying a plane into a big building prefabricated for him?

I suspect that this question might overstep the bounds of polite discourse, and apologize to any of my friends who might be distressed by it.

However, if memory serves there are a number of large buildings on the other side of the Pacific Rim in countries not entirely free from political strife and cultural repression. Some even already have heroic suicide themes in their national narratives. The US is capable of breeding terrorists domestically, like maggots arising spontaneously from the rotten parts of the country. The meme of flying an airplane loaded with fuel into a building full of people is completely out in the open, now, not just in technothrillers. Nobody has to invent the idea from scratch.

So, is architecture responding to this? The meme's loose in the architects too, so surely it must be?

I certainly hope that architecture and civil engineering are responding, because terrorist engineers will surely learn from the mistakes of the criminals on 11 September, 2001.

Well, remember that I'm a student, not a professional. That said, the subject is much debated.

The WTC was designed to withstand aircraft impacts and did withstand the actual impact, as far I can tell; it took those tons of burning fuel to weaken the frame sufficiently to bring on collapse. So the code authorities, fire experts, and so on are studying the attack and I expect changes. We can probably design buildings that will resist the sort of attack undertaken on 9/11. But such an attack is unlikely to occur again and no structure is going to be resistant to every attack.

On what basis does one form the conclusion that such an attack is unikely to occur again? I put it to you that now that the idea is out there, further attempts will be made, and there is a finite possibility that at least some of them will succeed.

Also, from some of the descriptions of the consequences of the airplane impacts, it seems that "surviving the initial impact" didn't include the emergency staircases still being useful for escape from the burning buildings shortly after the impact.

Bob: You ask, "On what basis does one form the conclusion that such an attack is unikely to occur again?"

I would say the evidence is already before us: The attempt to use Flight 93 failed only 40 minutes after the other attacks had succeeded. No one will, in the future, respond to hijackers in such a way as to allow what happened to flight 11 to happen again.

Now, a determined terrorist could fly a small plane packed with explosives into a tall building, but that's much less likely to topple a tall building than a jumbo jet packed with fuel was.

Kevin, I take your point, but I don't think that it fully addresses the issue, for several reasons. For example, a more heavily armed team of hijackers, or differences in the occupancy of the passenger cabin, might make the difference to the success of the terrorists. Or the weak link to break might be the flight safety arrangements for the pilots. Or the approach might be to get an operative into position to take over a cargo plane heading out on a Transpacific run.

For another thing, actually toppling a building is not the only outcome that could be a goal for a terrorism ring. Death and destruction are the goal: the complete destruction of those towers and the complex beneath them was spectacular, but even killing a few hundred people in the upper floors would have been a noteworthy slaughter and a dislocation of society of the kind terrorists seem to aim to achieve.

My main point, though, is that with this evil idea out in the open, clever evil people will undoubtedly seek ways to "improve" upon it. It's damn hard to retroactively add security even to a a simple, bounded artifact like a computer system, and as an engineer I'm sure that the attempt to add security to the world's air transport system is sure to leave exploitable weak points.

I am not interested in spending mental energy on improving anybody's terror plots for them, so I won't dig up and present vulnerabilities and exploits. But I think we shouldn't be complacent about attacks on tall buildings with airplanes being a thing of the past in the United States or, even more so, elsewhere in the world (and the scope of my questions to Randolph was intended to be global).

I don't think there are any places where the local air force will allow this kind of attack, now that there is awareness of the possibility. The 9/11 attack would have failed if the USA was flying domestic air patrols; the USA was, in my view, overconfident. Bob, I think you are also focused too much on tall buildings; if this kind of attack can succeed at all there are many possible targets.

Okay, Randolph, let's suppose that a large airplane, fully loaded with fuel, is under the control of terrorists when, or shortly after, it takes of from Newark. What is going to be under it when it's shot down, and how does having the USAF kill American civilians in the airplane and on the ground NOT serve terrorist interests?

But leaving aside the moral, ethical, and political dimensions of shooting down your own citizens over one of your own cities, this is my main point:

Saying that the structures might have survived the impact of an airplane is misleading. Exit stairways did not survive the initial impact, and people on upper floors of the WTC buildings were trapped and would likely have died of smoke inhalation or actual fire. Many died because they could not escape from the upper floors. I don't expect any building to withstand every attack, but I'd like to see some acceptance of the fact that having the structure survive isn't the ultimate goal: the structure has to survive in such a way that the occupants have a chance to escape.

If a successor to the WTC can't do better in the face of a terrorist attack, or even a bad accident, we will show that we have learned nothing from the experience. There are an infinite number of ways we can be caught off guard, and your reaction makes me think that overconfidence is still a problem.

As Bruce Schneier sometimes say, "Security is a `weakest link' matter." When other links on the chain had broken off and a tower was on fire, people died because the link in the chain that should have allowed them to escape with their lives was too weak to serve them.

Even if we strengthen all the other links which failed on that day, they will not be unbreakable, and one day people will again be faced with the outcome of decisions by architects, builders, engineers, owners, and construction workers as their route to life or to death. Saying, "It won't happen again," just doesn't cut it as a rational basis for planning.

That would be like the Bloomberg administration continuing to find reasons not to address the failures of communication for the Fire Department and Police and Ambulance that the Giuliani administration decided not to spend money on. It was a weak link, it cost lives last time, and if it's not changed, it will certainly cost lives in the future.

I can focus on plenty of other subjects besides tall buildings. I live in a part of greater Boston pretty close to the LPG tank farms and the waterways the LPG freight ships traverse to make their deliveries, and how financial interests are put ahead of public safety such that this problem is not redressed.

But this was a specific question in a specific thread, so I'm focusing on the habit of builders of tall buildings to cut corners on escape routes and other "overhead" items that only benefit the inhabitants of the buildings, not the buildings' owners.

...and then my life got busy and I had to drop this discussion. Um, sorry.