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Classical (Langmuir) probe theory is reviewed and the conditions under which it is applicable to the re-entry physics problem identified. Some later developments in probe theory, which account for flow velocity in the free- molecular case, are presented. Measurements of current densities have been made with ion probes mounted flush in the walls of a pressure-driven shock tube; the results are interpreted using a one-dimensional, collision-dominated probe theory, allowing for the spatial nonuniformities in ion density. Correlation of the probe theory with a zero-order gas dynamic boundary layer theory is shown to lead to theoretical current estimates in fair agreement with the experimentally observed values. Some shock ionization precursor results in air are also presented. Finally, the results of some calibrations on probes that were flown on the RVIP and LORV programs are presented.

Measurements were made to determine the difference in blast effects over a surface covered with low shrubs and grass and over a cleared sandy surface in the precursor region, and an attempt was made to correlate this difference with measurements of preshock sound speed over the surface. Overpressure was measured with groundbaffle gages and with pitot-static gages at 3-foot elevation. Dynamic pressures were measured at the 3-foot elevation with the pitotstatic gages. Measurements were made at the same ground ranges for vegetated surface as for the sandy surface. The vegetation reduced the severity of the precursor, showing later arrival times and smaller dynamic pressures than over the cleared area. The overpressures over the vegetation were the same at the ground and 3-foot levels. No measurements of sound speed after zero time were obtained, so a correlation is not possible., Report on Operation REDWING-Project 1.10.

The objectives of Project 1.3 were to spot-check the theoretical relationship between dynamic pressure and overpressure in the 10-to-40-psi overpressure range and to evaluate a group of gages measuring various blast parameters. The one measurement of dynamic pressure in Shot 6 agreed with that implied by the overpressure; in this case the shock had traveled 800 feet over land immediately before reaching the gage. In Shots 4 and 5 measurements of dynamic pressure by the gage group were all high; in this case the gages were near the water's edge. These latter records also showed peculiar waveforms, indicating that the shock had picked up water and/or dust. The force plate and density gage seem to be suitable for field use, but their response to dust must yet be studied. (Author), Report on Operation Castle--Project 1.3. (U)

El objeto de este estudio es la investigación de los distintos nombres con que en el curso de los siglos ha sido conocido el lugar tradicional del nacimiento del Bautista. Se prescinde, por ahora, del examen crítico de las fuentes en que creen poder apoyarse las varias opiniones que en el pasado han sostenido exegetas y topógrafos al querer localizar la patria del santo.