Value chain · CLM-1013
In plain terms
By 1980 the programme had made the upper ionosphere ripple with a heater running at what it reckoned was four to twelve times the beam's strength, and seen satellite signals flicker as a result, while a radar looking for the same ripples saw nothing. Whether any of this applied to the real beam depended on a scaling rule nobody had tested.
The claim as recorded
The DOE 1980 summary reports the first underdense-mode self-focusing experiments: Platteville "can provide more than 5 times SPS-equivalent power density to the ionosphere at 300 km for a 10-MHz scaling" and "more than 50 times" at 5 MHz; with the heater "operating in the underdense mode" the LES-8 satellite signal observed from an aircraft showed that "ionospheric irregularities were created and that these irregularities induced scintillation" at a cube-law equivalent of "about 280 mW/cm2"; ground observation at Carpenter, Wyoming, along the magnetic field "clearly show effects of ionospheric irregularities" at "about 90 mW/cm2 of SPS comparable power density"; an HF backscatter radar "provided no evidence of backscatter from ionospheric irregularities. The reasons for these preliminary results are not yet understood"; and the source states the results "cannot be interpreted at this time for the SPS reference system" because that "depends upon a validation of the 1/f3 scaling law".
Evidence behind this: T3-programme summary of preliminary underdense-mode results whose SPS equivalence rests on an unvalidated law.
Scope and limits
"Only preliminary results are available"; no dates, durations, heater power or scintillation indices are given in the summary; the detailed volume is SRC-110, held, not re-read here, and CLM-0163 (from it) covers the D/E-region circuits and not these F-region experiments. The Carpenter geometry "maximized the effect", per the source. The 280 and 90 mW/cm2 equivalents exist only under the unvalidated cube law: on an inverse-square law the same experiments would be at much lower SPS-equivalent density.
What it assumes
That "underdense mode" means heater frequency above the F-region plasma frequency, as the source uses the term.
Where it comes from
p.98 / 88, render read: "The Platteville facility can provide more than 5 times SPS-equivalent power density to the ionosphere at 300 km for a 10-MHz scaling to the SPS operational scenario (1/f3 scaling). At 5 MHz, the SPS equivalent power energy is more than 50 times the SPS operational power density of 23 mW/cm2." p.99 / 89: "The LES-8 signal was observed on the aircraft when the Platteville facility was operating in the underdense mode. Using the 1/f3 scaling law for thermal self-focusing, the power density in the F-region was calculated to be about 280 mW/cm2 for this experiment. The results indicated that ionospheric irregularities were created and that these irregularities induced scintillation in the LES-8 signal ... This determination depends upon a validation of the 1/f3 scaling law"; "The results of these experiments clearly show effects of ionospheric irregularities on the LES-8 satellite signals. These preliminary results, however, cannot be interpreted at this time for the SPS reference system. The 1/f3 scaling law is yet to be validated, but if correct, indicates that about 90 mW/cm2 of SPS comparable power density was delivered"; "the radar provided no evidence of backscatter from ionospheric irregularities. The reasons for these preliminary results are not yet understood."
Basis: mW/cm2 SPS-equivalent on the 1/f^3 law
Related records
- Answers question
- QST-002 not published in this releaseQST-009 not published in this release
- Contradicts
- CLM-0083 The formula is the right type but nobody has said how far it can be pushed, and at space solar... (the "no underdense self-focusing experiment has been attempted" half SRC-108's 1978 statement carried forward; the "no experimental verification" half is qualified not contradicted)
Cite this
energyaperture.com/c/clm-1013
CLM-1013, Energy Aperture, as of 1980-08.
Connected records
Other published records linked to this one. A list, not a judgement.
- Also from SRC-086
- CLM-0020The original 1978 design set the beam at 230 watts per square metre in the middle of the receiving site, about one twenty-third of that at...CLM-0024The American standard of the day allowed 100 watts per square metre averaged over six minutes. The US had no separate limit for the public...CLM-0036The 1980 American assessment said people living or working near the receiving site, outside its exclusion boundary, would generally be...CLM-0153A 1980 US government environmental assessment argues, without a formal calculation or test, that an aeroplane's metal body would shield...CLM-1005The 1980 assessment explains where the 10 milliwatt limit came from: a heating threshold of 100 divided by a safety factor of ten. It also...CLM-1006In 1980, by the US assessment's figures, the Soviet limit for the general public was two thousand times lower than the American 10...CLM-1007The 1980 assessment worked out that a full American deployment would raise the microwave background everywhere in the country to about...CLM-1008The 1980 documents give the beam's strength at the satellite, on failure, and above and below the receiving panels. The summary and the...More on the source page.
- Also from SRC-529
- CLM-1005The 1980 assessment explains where the 10 milliwatt limit came from: a heating threshold of 100 divided by a safety factor of ten. It also...CLM-1006In 1980, by the US assessment's figures, the Soviet limit for the general public was two thousand times lower than the American 10...CLM-1007The 1980 assessment worked out that a full American deployment would raise the microwave background everywhere in the country to about...CLM-1008The 1980 documents give the beam's strength at the satellite, on failure, and above and below the receiving panels. The summary and the...CLM-1009The 1980 programme tested bees because of pollination. Early results showed no effect at the beam's strength, and one preliminary report...CLM-1010In the US Department of Energy's 1980 assessments the only bird numbers were from quail eggs at a fifth of the beam's peak, which hatched...CLM-1011In 1980 the programme used two different rules to translate its low-frequency experiments to the real beam, one for heating and one for the...CLM-1012In the DOE's 1980 summary the Platteville heating tests showed no effect on the navigation and broadcast radio it listed at the beam's...More on the source page.
- Contradicted by
- CLM-0083The formula is the right type but nobody has said how far it can be pushed, and at space solar power frequencies the wave is about 200...