Scans of old papers

Birch, Brakke, Lofstrom, Pearson, Knapman

A short history of space elevators and related concepts from Jerome Pearson. The most complete timeline before Jerome's death in (2019?). Jerome and Paul Birch and I collaborated on a NASA NIAC proposal for orbital rings in the 2010s. I never visited him in Myrtle Beach, SC, but did visit me in Oregon a few years ago.

First launchloop paper, American Astronautical Society readers form, undated but possibly November 1981. AAS readers forum was published 6 times per year, and I started the correpondence with editor Herb Raush after the July newsletter.

Ken Brakke's Skyrail paper in July 1982 L5 News.

My Launchloop paper in the August 1982 L5 News.


Paul Birch's Orbital Rings papers in the Journal of the British Interplanetary Society.

When Ken and I read the 1982 paper, we invited Paul to meet us at the 1983(?) Princeton Space Development conference. We spent a few days talking mathematics, and developing common nomenclature and equations. Ken was a math professor, Paul had solid UK university training, and I were an inginier. Whatever I got right mathematically is their coaching.

Among the organizations outside the conference area was the SEDS table, Students for the Exploration and Development of Space. Jeff Bezos was a Princeton student at that time, and it is very likely he helped staff that table. I don't remember him, and with luck he doesn't remember me.

Perhaps during the same trip, I visited Stan Schmidt in New York, arranging for a "fact" article in Analog Science Fiction / Science Fact, published in the December 1983 issue. Newsstand magazines have a long pipeline, so the process may have started sooner.

I presented the first full-mathematics paper at the AIAA-etcetera Spring Joint Propulsion Conference in Monterey CA:

I presented a more mathematical paper at the 2009 International Space Elevator Conference in Seattle:

At a subsequent conference, I presented a paper describing some new space elevator pathologies. Perhaps the main one is that perfect carbon nanotubes are superubricious, they have the crossbundle shear strength of a perfect lubricant. Weaving carbon nanotubes would be like weaving motor oil.

A positive aspect of that experience is a design for "acoustically powered" space elevator climbers; longitudinal tension waves can be "quarter-wave" coupled to a climber and power it like a very fast earthworm (with suitable anti-resonant damping for the payload).

While this is no good for climbing a lubricant, it will be helpful for launch loop maintenance robots climbing "ordinary" Kevlar or Dyneema stabilization cables on a launch loop.

Conversely, I also showed that a sudden shock (like a jammed wheel on a climber) can launch a wave downwards towards the Earth attach, and upwards towards the counterweight, where it will bounce and reflect and double. Tapering (as happens on the top and the bottom) does not attenuate the wave, instead increases amplitude in the "higher impedance" "acoustic" environment, increasing shock energy density. This will be a problem for launch loop anchor/stabilization cables; fortunately, the maintenance climber robots on those cables will move much more slowly and energetically.

Not mentioned above is another current collaborator, British engineer Dr. John Knapman, who has also presented many times at ISEC, and often acts as their research director. John has also published dynamic structure papers in the JBIS. I will include pointers to those Real Soon Now.

Years ago, John and I visited Paul Birch at his home on the Isle of Wight. Paul recited Tennyson on Tennyson Downs near the Needles; I guided them down a narrow cliffside path to some crumbling steel and concrete structures on the side of the cliff, the remains of the rocket engine test stands for the Black Knight rocket.

Scans (last edited 2023-04-03 02:39:47 by KeithLofstrom)