Rocket science, as easy as IKEA

The startup rewiring the world

In today’s Diary:

• The medieval way to wire a rocket

• 120 feet of secret purple cable

• The cardboard boat mindset

• Veteran eyeballs turned into software

• From pizza robots to defense systems

Hey Rational Optimist,

This month I trekked across America and met 40 innovators, getting my hands on some of the coolest technology being built today.

I saw a live nuclear microreactor in the Utah desert making electricity…

A quarter-scale prototype of an airship that will be bigger than the Hindenburg…

A startup building “bodyguard satellites.” And a machine that can sniff out deadly pathogens nobody has even named yet.

There’s nothing as invigorating as standing next to real hardware while the founder walks you through all the tricks it took to make it work. Only in America!

I’ll tell you all about these innovators in the coming weeks. To understand why these founders have me so fired up, you first need to understand what went wrong.

America stopped making real things.

In 1904 New York opened its first 9 miles of Subway for roughly $1.3 billion in today’s money. Dug by hand, with shovels.

Today the same city, with modern tunnel-boring machines, takes a decade and $4.6 billion to build less than two miles!

That’s just one example of how, in many ways, America literally went backwards at building real, physical things.

Rational optimists know bureaucracy, aka “The Blight” is partly to blame. The real self-inflicted wound is America chose to let other countries handle the greasy business of making things.

For 40 years America told itself what mattered most was designing products, moving money around and selling ads. Manufacturing was for losers.

The whole belief system fits in eight words printed on my Apple AirPods: “Designed by Apple in California… Assembled in China.”

When you stop building things you don’t just lose jobs. You lose something far more valuable: the know-how.

My favorite example is the Transformer, the “T” in ChatGPT.

The Transformer was invented at Google in 2017 by a team trying to find a better way to translate English into German. They were running rooms full of powerful chips, but translation software back then read one word at a time. So their $100 million of hardware sat mostly idle, waiting for the next word.

The team asked: “What if the software read every word in the sentence at once?” That idea became the foundation of ChatGPT.

That’s how innovation works. Every breakthrough is the solution to a bottleneck, and bottlenecks only reveal themselves in production. Whoever runs the machines invents the next Transformer.

You can’t simply buy know-how. In many cases the ability to make critical parts lives in a few aging skulls.

When Ukraine burned through America’s stockpile of Stinger missiles, the Army ordered 1,700 new ones. Easy, right? We’ve had the blueprints for 50 years.

Then Raytheon tried to build one. Raytheon President Wes Kremer said: “We were bringing back retired employees that are in their 70s… to teach our new employees how to actually build a Stinger.”

The companies that matter most right now are the ones making knowledge transferable. They take jobs that used to require a two-year apprenticeship and rewrite them so a smart kid can do them in a month.

That’s exactly what one founder I visited on my recent trip is doing.

Jordan Black was a top SpaceX engineer. Then he quit.

Three years ago, he started building wire harnesses on the carpet of his apartment.

This is a wire harness, and it runs your life:

Harnesses are a custom-built bundle of cables and connectors that, for example, carries power from your car’s battery to the headlight.

Jordan told me a rat chewed through the harness in his Toyota. The dealership quoted him $5,000. Jordan’s reply: “You’re talking to the wrong guy. I’ll fix it myself.”

Your car contains about 40 harnesses, holding over 3,000 wires. A single SpaceX Falcon 9 rocket has around 1,000 separate harnesses. Every drone, fighter jet, and missile runs on them too.

And today virtually every wire harness is still made by hand!

As Jordan explained it to me, you start with a board the size of a ping-pong table. Pin the harness drawing across it. Hammer in pegs along the route the wires will follow:

Now cut hundreds of wires, each a different length. Strip the rubber off each end by exactly the right amount.

Route each wire by hand around the pegs. Now crimp a tiny metal terminal onto each wire’s end, squeezing it down with a hand tool. The crimp is smaller than your fingernail. Get it slightly wrong, and you’re ripping wires out and starting over.

Next you must fuse each wire to its pin with a drop of molten metal by hand with a hot iron, one joint at a time.

Then do it all again. Every harness is a custom, one-off model. Standing over one harness Jordan showed me a cable which must route around a component that runs hot. Every machine is different, so every harness is too.

Worst of all there’s no manual for any of this. You learn wire harnessing the medieval way: shadow a veteran for a year and hope you pick it up.

That’s why it takes 12+ months to train a wire harness technician, even at SpaceX.

During his tenure Jordan discovered roughly 40% of technicians’ days were spent reading spec sheets. Nearly half the working hours of the most talented aerospace technicians on Earth were spent staring at instructions. Jordan thought…

What if we make wiring a rocket as easy as following IKEA instructions?

That idea became Senra Systems.

Senra builds software that lets you design a new harness in minutes. The software converts every design into precise, visual, step-by-step work instructions. New workers can start building in weeks, not the year it usually takes.

Senra doesn’t sell the software. It uses the software to run its own harnessing factories.

Only three years after founding Senra produces 1,000 harnesses a month, and its customer list reads like a who’s who of American aerospace and defense. It’s targeting 10,000 a month next year out of its new 80,000-square-foot factory in Cypress, California.

Senra delivers harnesses in weeks compared to the industry standard of six months.

If you’re wondering about the name: “Senra” is harness spelled backwards, minus the H and the S. Why drop those two letters?

Jordan: “Because we’re deleting the horseshit of harnessing.”

Last week Senra announced a $65 million Series B funding round, co-led by Lowercarbon Capital and Interlagos, with General Catalyst, Sequoia, a16z, Founders Fund and 8VC piling in. For full disclosure, the founders of Rational Optimist Society have established a small fund that makes investments in companies we believe in, and our fund is participating in this round.

Senra was a slam dunk investment for three reasons.

First, Jordan is top tier. He spent five years at SpaceX and became the youngest manager ever on its Avionics R&D team.

ROS members know I’m a SpaceX mafia fanboy. A generation of engineers went to the school of Elon Musk. Now they’re taking the SpaceX playbook to every broken industry.

When Jordan was starting Senra he flew around America carrying: a wire-stripping machine about the size of a printer and a 600-page book on how to build wire harnesses today.

He’d set them side by side for investors. Here’s the old way: manual tools and 600 pages. Here’s the new way: one button. You choose.

I asked Jordan the most important lesson he took from SpaceX. Knowing I live in Abu Dhabi, he said: “There’s always a way to figure something out. If we had to get to Abu Dhabi tonight and there were no flights, we’d build a cardboard boat if we had to.”

That’s the SpaceX mindset in one sentence…

“Figure it out.”

Second, Senra is solving the know-how bottleneck. Until now building a harness basically required a PhD in the craft.

Remember the 40% of the day SpaceX’s technicians spent reading instructions? The software gives them back that time.

Lastly, Senra is a glimpse of the future of work in America.

Most of Senra’s workforce had never seen a wire harness a few months ago. Now they’re building flight hardware. I asked Jordan whether working with your hands could become high-status again. He lit up: “It’s changing, and places like Senra are the perfect place to start.”

He was emphatic on this point: Senra isn’t automating people out of jobs. It’s taking people in, training them, upskilling them.

That’s what the future of work in America can look like. Making real things and creating great-paying jobs at the same time.

I walked into Senra’s HQ and saw…

A 120-foot-long wire harness laid out across a giant steel table. Thick purple intertwined cables ran almost the length of the room.

A customer had called Senra at the eleventh hour because this one harness was holding back a multi-billion-dollar program. Senra had two months to figure it out and build it.

Without naming names: I watched the nervous systems of some of America’s most critical defense hardware being built on tables in Redondo Beach.

Walking around what struck me was how calm everything was. I asked Jordan how this compared to a traditional wire harnessing shop. “They’re not looking at a drawing or trying to find a tooling. The operating system is giving them that perfect recipe on a silver platter.”

At a traditional shop, he says, the instructions are “a piece of paper or a printed-out email from the customer.”

Remember the crimp, that fingernail-sized connection that can doom a whole harness? Inspecting crimps used to mean a veteran with 20 years of practice squinting at each one. At Senra a technician puts the crimp under a camera, hits capture, and the system passes or fails it on the spot.

Every inspection feeds a growing library of what good and bad look like. Senra is capturing the judgment that used to live in a retiring veteran’s eyeballs.

And harnesses are just the entry point. Jordan’s strategy is “start with the high end and work your way down.” Win the hardest, most demanding customers in aerospace and defense first, then expand into everything else that needs skilled assembly.

The endgame: You go to a website, design your part, click buy, and get it two weeks later. Amazon, but Made in USA.

For 50 years America’s brightest kids made
apps and sold ads.

Today the sharpest people I know are choosing different quests: reactors, airships, satellites… and wire harnesses.

Talent is the leading indicator of every boom. It’s already shifted. The rest of the country just hasn’t noticed yet.

America needs more missiles, satellites, data centers, nuclear reactors… at the exact moment the workers who know how to assemble them are retiring.

The winning strategy is giving humans superpowers. That’s what Senra is doing, and it won’t be the last.

Reindustrialization will be one of the great investment themes of the next decade. But most startups will fail, so you need a way to separate winners from losers.

Here’s mine: when a company builds its 1,000th unit, will it be better than its first? The winners capture the know-how from every unit they ship so the company constantly levels up.

Look for a boring, fragmented industry. Bonus points if the founders came from SpaceX. Expect many future billion-dollar companies to fit that description.

We told two generations that working with your hands was a dead-end job. Wrong. A kid who walks into Senra today is building flight hardware within a month, no four-year degree required. Put the trades back on the menu. Most importantly…

Go see something real being made.

It’s the reason I jump on planes and fly 20+ hours to California. Nothing will make you more optimistic about America than standing on a factory floor watching things get built.

Visiting 40 founders over the past few weeks, I saw a future where the dude who makes things out-earns the guy who makes PowerPoints about them.

Where towns that lost their factories get them back, with better jobs than before.

Where “Made in America” stops meaning expensive and slow and starts meaning cheap, fast, and high-quality.

When Jordan Black quit SpaceX to build wire harnesses in his apartment, his first customer was a pizza robot company. Today his parts power some of America’s most critical systems, and he’s teaching an army of new workers how to build again.

That’s what I call a rational optimist.

Hit “like” and “restack” to get more eyes on the people building real things.

—Stephen McBride