The Daedalus Files

Foreword

Slingshot is my novel about constructing the world’s first Space Launch Loop. The inventor of the concept, Keith Lofstrom, wrote the foreword to that novel. Here is a portion of that Foreword.

Imagine a stream of water out of a fire hose. Without air friction, the stream might make a parabolic arc 20 meters high. Faster, and the arc goes higher and farther. A stream moving 7.3 kilometers per second would come down on the other side of the planet, and a stream moving 11 kilometers per second would keep going into interplanetary space. Wrap the stream in a frictionless hose, and...THAT won’t work either. But what if...?

The launch loop: REPLACE the water with flexible iron pipe, 5 centimeters outer diameter, 3 metric tons per kilometer, moving at 14 kilometers per second. Bend it to the curvature of the earth with a stationary magnetic track, 7 metric tons per kilometer, 2,000 kilometers long, at 80 kilometers altitude. Stabilize the moving iron with electromagnets controlled by fast electronics. Turn it around at the ends with powerful magnets, and complete the loop.

On the eastbound section, 5-metric-ton payloads ride on magnets designed for high drag, which accelerates payloads at 3 gees. Payloads exit the east end of the track between 7.7 and 11 kilometers per second, to equatorial low earth orbits, to the moon, or to interplanetary space. Launching a payload weighing 5 metric tons to low earth orbit consumes 180 megawatt-hours, about $15,000 worth of electricity, or $3 per kilogram of payload. Passengers will still need vehicles and air, but freight can be launched on wooden shipping pallets. This small launch loop can launch 2,000 5-metric-ton payloads to orbit per day. Heavier launch loops can launch thousands of standard 30-metric-ton intermodal shipping containers per hour. They can also store peak power for the global electrical grid. Space travel can be as cheap as ocean cargo travel.

In the early 1980s, I published in an American Astronautical Society Newsletter and other journals, and presented at many conferences. In England, physicist Paul Birch wrote about orbital rings in the Journal of the British Interplanetary Society. Ken Brakke, a math professor in Pennsylvania, published his version of orbital rings.

Ken, Paul, and I met at one of the Space Studies Institute conferences at Princeton. We spent three days developing nomenclature, doing math, finding errors and fixes. I met Robert Williscroft in the mid-1990s in Philadelphia while I was on a trip to the East Coast. He had contacted me about a novel he was outlining—Slingshot. We spent a day together becoming acquainted, and have kept in touch since then. Slingshot in its current form is a result of our brainstorming during that visit.

For years afterward, Paul and I swapped ideas. Under Jerome Pearson’s leadership, and with our friend John Knapman, we submitted grant proposals until Paul’s untimely passing in 2012. We were friends, never competitors, though Paul was much better at reciting Tennyson. I hope one of us will be the first launch loop astronaut. Conflict makes great stories, but friendship makes great lives, so I now pass page control to my friend R.G...

So there you have it. I wrote Slingshot. It was launched at the International Space Elevator Conference in Seattle in August 2015, and the book resides on the desk of every Space Elevator scientist in the world. Space Launch Loops appear in the subsequent books in The Starchild Trilogy, and anyone familiar with my Trilogy knows all about these commercial space launch systems.

When I discovered the Gryphon rigid wingsuit, the four-part story you are about to read pushed itself into my consciousness. The Gryphon is a perfect accouterment to U.S. Navy SEALS operations. Chapter one is the natural consequence of Slingshot’s skyports effectively being 80 km tall towers. Chapter two takes it to the next logical level—Low Earth Orbit (LEO). Chapter three brings an entire SEALS squad into the action, and chapter four drops the SEALS squad from LEO into live-action.

I challenge you to find the fine line between reality and fiction in these stories.

Robert G. Williscroft

Centennial, Colorado

February 2020