Craters were observed resulting from square arrays of 64-pound charges at various spacings and depths. The closest spacings yielded craters very like those from single 256-pound charges, while wider spacings yielded craters more or less square in shape and with a mound or pier at the center. Generally, the areas so uncovered were greater than for single 256-pound charges, except for very deep charges. Volumes, too, were enhanced by this configuration by as much as a factor of three. If the same factor is maintained for nuclear charges, the cost per unit volume of a crater from such an array will be within 20 percent of that for a single charge.

This report on the RFD-1 optical data and external fuel-element experiment includes a description of the instruments and test components used, a presentation of the data obtained, an explanation of the methods of data reduction employed, and a statement of the conclusions derived. It covers the theory, design, qualification tests, flight-test data, and results of the external fuel-element experiment. Also presented is a theoretical analysis of observed versus predicted ablation times and altitudes for the external fuel elements. In addition, this report presents recommendations for improvements to data acquisition and reduction methods in future, similar flight tests.

Re-entry flight demonstration number one (RFD-1) was launched on May 22, 1963 from the Scout launch complex at NASA Wallops Station, Wallops Island, Virginia.

Abstract: The purpose of this report is to describe the problems inherent to general dielectric strength measurements, and to act as a guide in establishing a method for pulse dielectric strength measurements.

Forword: The International Symposium for Packaging and Transportation of radioactive materials held at Albuquerque, New Mexico, January 12 to 15, 1965, was a joint effort on the part of the Sandia Corporation, the Albuquerque Operations Office, and the Headquarters, U.S. Atomic Energy Commission.

Abstract: RFD-2 was the second of Sandia's operational safety flight tests of systems for nuclear auxiliary power.

Abstract: "This brochure presents a brief introduction to the Positional Tolerance Method of DImensioning as employed by Sandia Corporation. The emphasis is placed on the elimination of ambiguities and increase in tolerances provided by this method as compared to the older, bilateral method."

Abstract: This report describes the SNAP-10A Simulated Test Reactor, the test philosophy of Re-entry Flight Demonstration Number One, the analytical analysis of reactor disassembly, and the results of the flight test.

The need for special high velocity shock testing is pointed out and equipment that has been developed to meet these needs is discussed. The concept of velocity-change and its importance in shock-testing technology is brought out. The three types of equipment discussed are: accelerated drop testers, pneumatic actuators, and air guns. Examples of each type and their capabilities and limitations are presented.

Abstract: Tests were made on 24 simply supported, post-tensioned, end-anchored, prestressed concrete beams with and without web reinforcement.

Abstract: This report presents the vapor pressures versus temperature data graphically for the rare earth elements, yttrium and scandium.

Foreword: There has been relatively little work reported on deriving quantitative estimates of the degradation to a man-machine system resulting from human errors. One approach, used in the Reliability Department of Sandia Corporation, is presented here as an example of how such estimating can be done.

Abstract: This technical memorandum describes an automatic tester and recorder as it is used in obtaining fusing time information from electrical fuses for subsequent analysis in the IBM 704 computer.

Specimens of two ferroelectric materials, barium titanate and lead-zirconate titanate, have been subjected to high dynamic stresses by impacting them with a projectile accelerated by an air gun. The purpose of these tests was to supplement information previously obtained using high explosives to stress the ferromagnetic materials.

Abstract: This report constitutes the RFD-1 Safety Flight Plan for investigating the disassembly, distraction, and disposal of the SNAP-10A reactor during re-entry.

Abstract: Results of pressure tests of a reflection plane in the Sandia 12-inch transonic wind tunnel to determine lateral and longitudinal Mach distribution over the plate at 0.5≤M≤1.30 are presented.

Abstract: This memorandum discusses a new design definition technique, requiring no standard, which pictorially shows part and gage limits on the same drawing. When functional gages, test fixtures, or optical chart gages are the selected inspection method, design, manufacturing process, and gage engineers can use these drawings directly to replace the usual standards-based drawings. In essence, this advanced technology visually describes true position dimensioning and tolerancing. It enables product designers to directly control the acceptance process.

The present report describes the evaluations conducted with plated-through connections produced by techniques used by some of the prominent fabricators of printed circuits.

A plot of overpressure versus distance is presented for the fractional psi pressure level. The plot provides a rapid and simple means of estimating the permissible yield at any distance from settled areas.

Abstract: This report presents a summary and brief evaluation of the RFD-2 flight-test data reduced as of December 16, 1964.

Abstract: Methods are presented for calibrating a peak current gage which was developed at Sandia in the spring of 1953.

Abstract: Presented here are working graphs of pressure, density, velocity, and temperature from the Los Alamos Scientific Laboratory calculations (IBM Problem M) of a spherically symmetric explosion in a homogeneous atmosphere.

The experiment described herein has shown that the concept of low dams produced by ballistic collision of ejecta from simultaneous detonation of properly spaced parallel rows of charges is a feasible one. Rows of 8-pound charges were buried 3 feet deep with 4-foot spacing between charges. When two such rows of charges were placed parallel and 17.5 feet apart, the maximum height of the "dam" was achieved. The spacing of 17.5 feet between rows corresponds to 4.7 times the crater radius of one 8-pound charge at the burial depth which maximizes the single-charge crater. The extrapolation of these results to larger explosions is discussed. The height decreases and the width increases as the spacing between rows is further increased. The mass of material in the "dam" cannot exceed that in the crater of one of the rows. At the spacing between rows which maximizes height, the volume of the "dam'' is about 50 percent of maximum volume theoretically achievable. At wider spacings, the volume increases to 75 percent.

Abstract: This report describes two tests made to obtain data on the loads that equipment is subjected to during railroad switching.