Located in NY, it was the world's 7th tallest building but had a big structural flaw: a very strong storm wind could knock it over.
The expert architects had no idea, until an anonymous Princeton undergrad cold called them.
Here’s the story🧵
Today, the 59-story structure is called 601 Lexington Avenue.
The tower was originally built to house Citibank's headquarters and construction ran from 1974 to 1977 (it cost $175m and was later called Citigroup Center).
The 45-degree roof is a stand out in Manhattan's skyline.
The Citicorp engineering flaw starts at the base: the first 9 floors are built on stilts.
Why? St. Peter's Lutheran Church sits on the corner of the lot. The church refused to leave but agreed to renovations.
So architects used stilts to build Citi over a newly designed church.
The stilts were built in the middle of the building (to avoid the church), which created instability.
A team lead by famed structural engineer William LeMessurier had a solution: V-shaped chevrons (8-storys high) on the building frame that transferred floor loads to the centre.
However, the V-shaped chevrons created another issue: Citi's structure was very light vs. a normal skyscraper.
And strong winds made the building sway.
LeMessurier's 2nd solution: a 400-ton tuned mass damper that vibrates to reduce sway (it requires electricity, though).
In skyscraper construction, there are two types of wind to account for:
◻️PERPENDICULAR: Wind hits the face of a building
◻️QUARTERING: Wind hits the corners of a building
"Normal" skyscrapers are strongest at the corners. Citi was not normal and vulnerable to quartering winds.
LeMessurier modelled for perpendicular but *not* quartering winds...until an anonymous Princeton undergraduate called his firm's office in 1978.
The architecture student was researching Citi for a thesis paper and flagged the quartering wind issue.
The analysis was spot on.
With the info, LeMessurier and his team calculated that a storm with quartering winds strong enough to knock Citi over happens once every 55yrs.
BUT, that's only if the 400-ton damper works. If a storm cuts power, than a weaker storm -- that happens every 16yr -- could hit Citi.
There was a fix.
The tower's joints were originally bolted together. A process that is fine for a "normal" building but a big problem for Citicorp.
LeMessurier proposed welding steel plates over the bolted joints. It would cost $8m but insurance only covered $2m.
The fix needed to happen ASAP.
The hypothetical of a storm turned into a reality when a Category 4 hurricane (Ella) began forming on the East Coast in August 1978.
If it made landfall on New York and toppled Citi Tower, tens of thousands of lives were at risk.
LeMessurier pushed Citi to act fast and found an ally: one Citi EVP was MIT-trained engineer (John S. Reed).
Together they convinced the Board to take action and made a plan to covertly execute the welding.
NYPD and 2.5k Red Cross volunteers were put on standby for evacuation.
Over many weeks, a team of engineers welded in the evenings and throughout the early AMs.
The covert operation was never uncovered in large part because a number of newspapers (including the NYT) were dealing with worker strikes.
Luckily, Hurricane Ella never came.
For years, the public was oblivious to the Citicorp story.
That changed in 1995 when a New Yorker writer overheard the tale at a dinner party and interviewed LeMessurier for the piece.
One mystery remained: who was the Princeton student that contact LeMessurier's office?
In the early 2000s, BBC aired a show on Citicorp. A woman named Diane Hartley watched and realized the Princeton student that cracked the case was...her.
She never spoke directly w/ LeMessurier but the insight when she was a 21-year old student saved countless lives. Incredible.
If you enjoyed that, I write interesting threads like this 1-2x a week.
◻️The first tweet should read "architects AND engineers" (I didn't mean to call out only architects as everyone involved with building Citicorp missed the quartering issue)
◻️Here is the cover of @DianeHartley thesis paper
The amount of work Hayao Miyazaki and Studio Ghibli team put into a film is mind-boggling.
Each typically has 60k-70k frames, all hand-drawn and painted with water color.
This 4-second clip (“The Wind Rises”) took one animator 15 months to do. Insane.
The docu “10 Years with Hayao Miyazaki” shows him talking to the animator (Eiji Yamamori) after its done.
It’s so good:
Miyazaki: “Good job.”
Yamamori: “It’s so short, though”
Miyazaki: “But it was worth it.”
The animator gets a second of joy (he’s pumped) but on to the next.
Miyazaki doesn’t use digital FX or computer graphics. He believes “that the tool of an animator is the pencil.”
On a related note, here’s something I wrote about another Japanese legend dedicated to the craft (Ichiro Suzuki) and the art of mastery: readtrung.com/p/jerry-seinfe…
New York City paid Mckinsey $4m to conduct a feasibility study on whether trash bins are better than leaving garbage on the street.
The deck is 95-slides long and titled “The Future of Trash”.
Some highlights:
▫️The official term is “containerization”, which is the “storage of waste in sealed, rodent-proof receptacles rather than in plastic bags placed directly on the curb.”
▫️Two main types of containerization: 1) individual bins for low density locales; 2) shared containers for high-density.
▫️NYC needs to clean up 24,000,000lbs of garbage a day
▫️Containerization has only become the norm worldwide in major cities in the past 15 years.
▫️New York City first considered containerization in the 1970s but never conducted a feasibility study until now (Mckinsey’s sales team has been dropping the ball)
▫️Key considerations for container viability:
• POPULATION DENSITY: NYC has 30k residents per square mile (more dense than comparable big cities)
• BUILT ENVIRONMENT: Few places to “hide” containers due to history of infrastructure development.
• WEATHER: Snow creates challenges for “mechanized collection” in the winter.
• CURB SPACE: Mostly taken up by bus stops, bike lanes, outdoor dining and fire hydrants.
• COLLECTION FREQUENCY: NYC needs to double frequency of pick-up for estimated speed of trash that bins would accumulate.
• FLEET: A new garbage truck will needs to be designed to collect rolling bins at scale.
▫️ The proposed solution (literally garbage bins and shared containers) covers 89% of NYC streets and 77% of residential tonnage.
▫️The three case studies — because you gotta have solid case studies — are Amsterdam, Paris and Barcelona.
▫️There is a slide called “Why containerization matters” and three reasons are “rats”, “pedestrian obstruction” and “dirty streets” (the 21-year intern that did this slide billed at prob $10k an hour is my hero).
The study is actually pretty interesting.
I have no idea if $4m is a rip-off to learn that “yeah, we should put garbage in bins so rats don’t eat it” but I would have happily done it for 10-20% of that budget (and come to a similar conclusion).
It is actually an interesting deck. Just the thought of a 20-year old newly grad getting billed at an obscene rate to say”rats get to garbage” is kinda funny
Four more solid slides:
— By the numbers (daily garbage = 140 Statue of Liberty a day!!)
— City comparison
— Container comparison (looks like they did select the “scalable” trash bin)
— Curb side analysis
Think Mckinsey telling NY to “put garbage in bins so rats don’t eat it and people can walk” will work out better than when it told AT&T in 1981 that cellphones would be “niche.”
The Economist latest cover story on solar energy is packed with interesting stats.
▫️Solar energy will be the primary source of human energy use by 2040
▫️$500B spent on buying and installing solar panels in 2024 (nearly same “sum being put into upstream oil and gas”)
▫️Solar on track to produce “more electricity than all the world’s nuclear power plants in 2026, than its wind turbines in 2027, than its dams in 2028, its gas-fired power plants in 2030 and its coal-fired ones in 2032”
▫️Since the 1960s…the levelised cost of solar energy—the break-even price a project needs to get paid in order to recoup its financing for a fixed rate of return—has dropped by a factor of more than 1,000
▫️From the mid-1970s to the early 2020s cumulative shipments of photovoltaics increased by a factor of a million, which is 20 doublings.
▫️Over the same span, the “prices dropped by a factor of 500. That is a 27% decrease in costs for each doubling of installed capacity, which means a halving of costs every time installed capacity increases by 360%.”
▫️The cost of a kilowatt-hour of battery storage has fallen by 99% over the past 30 years.
The chart below — which they made vertical (kind of weird) — shows global useful energy consumption over the past century.
I’ll add two more posts after this one with excerpts on obstacles and opportunities.
— A lot of A/C for Sub-Saharan African (need 2TW of new solar just for Africa to reach India level of electricity use)
— Filter air continuously (reduce spread of airborne diseases)
— Carbon removal
— Water desalination
— AI/Data energy needs
Details from Red Lobster’s bankruptcy filing are wild and so much mismanagement:
▫️$1B in debt, $30m in cash
▫️Previous PE owner sold land and leased it back to Red Lobster at “above market rates”
▫️$20 Endless Shrimp cost it $11m but the interesting part is that one of the chain’s owners is Thai seafood firm Thai Union (which also owns Chicken By The Sea) and it may have used Endless shrimp to dump its own shrimp supply through the 578 restaurants in North America
▫️Thai Union became the only Red Lobster shrimp vendor, overcharging for shrimp and skipping quality reviews (Thai Union has written off its $500m+ investment)
▫️Red Lobster has had 5 CEO in the last 5 years (!!!)
▫️Sales down 30% since 2019
Red Lobster needed Yukitaka Yamaguchi — aka Japan’s Tuna King (sleeps 3 hours a day and knows where any fish is from on a single bite) — to run quality control.
Also, never forget Beyoncé name dropped Red Lobster with some R-rated verses in 2016 (“Formation”) and Red Lobster social responded and there was actually a brief sales surge.