How to Get to Orbit Cheaper than SpaceX's Starship
Ian Brooke has developed a new kind of jet engine that can act as the first stage of a rocket.
I get brunch with him every Sunday and have grilled him for hours on how it works.
Adaptive Cycle Jet Engines, the primer 🧵
Two facts about rockets:
- They have to carry a lot of fuel
- Structurally they are quite weak
The miracle of the Falcon 9 and Starship is they can be re-used, 10, maybe even 20 times.
But even a Falcon 9 that lasts forever has to consume massive amounts of fuel
On the other hand, commercial airplanes are designed for 30,000 cycles. They don't carry as much fuel for an important reason:
Jets use the atmosphere as a ladder
Air is mixed with fuel, combusted, and used as reaction mass. Rockets have to carry their own liquid air
"But jets can't go to orbit because they need air, and there's no air in space"
Space is an altitude. Orbit is a velocity
Using the atmosphere for reaction mass up to Mach 6 is like a free booster.
( Falcon Heavy boosters detach at Mach 10 )
This is the beauty of the adaptive cycle jet engine for orbit - a far more reusable first stage with tiny fuel requirements.
A second stage rocket takes you from Mach 6 to Mach 25, orbital velocity.
You skip using rockets when they suck - at low speeds with variable pressure
More re-usability, far less fuel, means cheaper, easier, more frequent launches.
To appreciate how it works, we need to look at the pinnacle of air-breathing engine design, the SR-71 Blackbird.
The fastest plane ever flown.
The SR-71 uses the J58 Pratt and Whitney engine, capable of two modes of operation:
Normal Turbojet, for speeds up to Mach 2.
"Turbo Ramjet," for speeds up to Mach 3.3
Ramjet mode is by far more fuel efficient, and can go up to Mach 6 in principle.
Ian's engine? Three modes
Three modes are what make this jet engine adaptive - maintaining high efficiency at different velocities.
Turbofan for low speeds, then Turbojet, then Ramjet.
What enables this is using a second turbine which is always running at its ideal RPM to drive the fan
Normal commercial jet turbofans are optimized to be efficient at cruising speeds, and so burn massive amounts of fuel at lower velocities.
Ian uses a second turbine that drives the main turbofan with a cryogen-cooled AC motors, like an electrical transmission.
This all sounds obvious - why now?
Electric motors are finally getting good enough in performance. Before, losses in the motor windings and weight would've killed the efficiency gains from having a second turbine drive an adaptive cycle jet engine.
Now it makes sense.
The net-net of all this is that @k2pilot developed a platform that traverses this entire chart to stay maximally efficient.
See how badly rockets perform at low velocities? Ian waits until ramjet speeds to use rockets. Smart.
But orbital launches are just the beginning
While the Space Launch market is projected to reach $30 billion in a few years, the commercial aircraft market is 15x larger.
Boeing and Airbus are the only two players. Both have become sprawling bureaucracies that don't innovate. 737MAX was a tragedy
The problem with trying to build a new commercial aircraft is that its absurdly expensive to certify and operate.
This means your jets have to be absurdly expensive too, or else just assume you can raise unlimited venture capital.
Boom goes your business model.
This is why people love @k2pilot's startup so much.
Like his engine, the company has three modes:
- Generate massive free cash flow through high-margin space launches
- Use this money and flight data to certify a new airframe
- Use this airframe to make the world 3x smaller
That's the win - Commercial flights anywhere in the world 3x faster than anything today, same price.
@k2pilot isn't competing with SpaceX.
Rather, he's building the Tesla of airplanes, to take on 110-year old Boeing.
Space planes just happen to be how you get there
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Biology evolves to the limits of thermodynamic efficiency, and we know from hardware engineering sending current down a wire is terribly inefficient compared to an optical waveguide.
Photonic computing is the future, and our brains might be doing it already 🧵
Computing means processing information, and Landaurs limit describes the thermodynamic minimun of entropy generated by overwriting a single bit of information.
The entropy cost only goes up as you include the non-reversible processes of mobile charge carriers dissipating heat
Getting more efficient computation means wasting less heat, beating the Landaur means making the computational steps information-preserving.
The greatest crime against humanity in history was committed in broad daylight.
+ Seven million dead
+ 70% of the world population injected
+ Civil liberties suspended
+ 13 trillion $ printed
+ Inflation and economic destruction
+ Intentional cover-up
Send them to the Hague
This is more spending than all major wars the US was involved in, combined. A death toll greater than the Holocaust.
Is this a conspiracy theory? No. An 8-month investigation CONCLUDED that Echo-Health Alliance engaged in gain-of-function research in Wuhan, China
Some of the first people to get sick with COVID? US-funded scientists working at the Wuhan Institute of Virology, you know, the place they were conducting gain-of-function research on coronaviruses.
A neat coincidence is how the Earth has naturally resonant frequencies if you think of the ionosphere as an electric 'drum', and this frequency range corresponds to the brains frequency of operation while meditating
Whats weirder is how solar activity might affect how you feel
There are some theories of consciousness that posit it inherently depends on the synchronization and resonance of electromagnetic fields across the body, so, not just neuronal firings but the fields those firings produce, across the somatic nervous system, vagus nerve, etc
What's known for sure is that brain wave patterns are very consistently tied to different kinds of cognitive activities, with higher frequencies associated with more excited states of alertness, concentration, creativity, etc
- There is a single objective reality
- Things outside your future light cone can't affect you
Yet quantum mechanics breaks at least one of these
Here's why Wigner's Friend thought exp. shows reality is stranger than we think 🧵
The setup is simple:
One person is in a lab making a measurement of a particle either spin up or spin down
Someone outside is waiting to hear the result. To the person outside, the lab is one big quantum system in superposition of two states
In 2009 Rachiger and Renner published an article that extended this simple thought experiment to involve many labs performing similar measurements in succession.
They reached the profoundly shocking conclusion that "Quantum theory cannot consistently describe the use of itself"
This is the most interesting physics paper I've ever read.
Maxwell's original equations have been greatly simplified to leave out an important part: Scalar Waves.
But the CIA already knew this.
If you want to know how electro-gravitic drone propulsion works, this is it: 🧵
Maxwell originally wrote out 20 equations in quaternion form which were then simplified into the familiar vector equations we all learn in undergrad physics that look like this.
The equations are the basics of all modern electronics, telecoms, power, energy, etc.
The hypothesis here is simple: what if instead of modeling electromagnetism with vector equations we stuck with the original quaternion form?
Quaternions are like imaginary numbers but with 4-components: three are vector components, one is a scalar.