It is desired at this time to present in summary form a factual history of the Building 234-5 operations, encompassing not only the immediate pre-start-up period from April to July, 1949, but including the major obstacles encountered in the succeeding interval to the end of 1949. This report is intended to serve not only as a review of 234-5 operations during this period but also as a documentary evidence of the difficulties experienced and the manner in which they impeded the start-up. This report presupposes a certain familiarity with the background of the 234-5 Building. To one unacquainted with the scope of this project, or for those desiring a background review, reference should be made to Document HM-253, ``234-5 Building Program Review``, by D.D. Streid, dated April 22, 1949. It must be realized that any attempt to discuss in detail all the circumstances and difficulties contributing to the start-up period would be disconcerting to the reader, and would very likely be repetitive. Therefore, although it is far from the writer`s intent that a cursory review will suffice, the presentation will be as nearly as practicable, chronological and comparative. For the sake of clarity it will be necessary to present several …

"A porous wall was used in an attempt to eliminate reflections of oblique waves from a tunnel wall. Calculations were made of the required resistance characteristics of a wall in order that the flow through the wall, due to the pressure difference across a shock wave, would equal the component normal to the wall of the flow behind the shock wave. The resistance characteristic of a sintered bronze wall was measured and the reflections of waves impinging on the wall were observed at a Mach number of 1.62" (p. 1).

Memorandum presenting an investigation of 4811C ceramic blades and the problems involved in the adaption of ceramic materials to stressed turbine components. Results regarding spin tests and rotating heat-shock runs are provided.

"An experimental investigation of the effects of injecting a water-alcohol mixture of 2:1 at the compressor inlet of a centrifugal-flow type turbojet engine was conducted in an altitude test chamber at static sea-level conditions and at an altitude of 20,000 feet with a flight Mach number of 0.78 with an engine operating at rated speed. The net thrust was augmented by 0.16 for both flight conditions with a ratio of injected liquid to air flow of 0.05. Further increases in the liquid-air ratio did not give comparable increases in thrust" (p. 1).

Report presenting the lift, drag, and pitching-moment characteristics of a wing-fuselage combination employing a wing with the leading edge swept back 63 degrees and cambered and twisted for a uniform load at a lift coefficient of 0.25 and Mach number 1.53. The experimental results are compared to those from other investigations. A maximum lift-drag ratio of 8.9 and a minimum drag coefficient of 0.0145 was obtained.

The slow neutron transmission of a sample of enriched uranium containing 3.193 gm/cm{sup2} has been investigated with a resolution width of 1 microsec/m (1 microsec/m is the full width of the triangular resolution function at the base) and with points spaced 1/3 microsec/m. The results of these transmission measurements are shown in Fig. 1. The solid line represents the new measurements while the dashed line represents the previous measurements (CUD-4) on this sample using a resolution width of 1.4 microsec/m and with points spaced 2/3 microsec/m.

Report presenting a wind-tunnel investigation of the longitudinal characteristics of a wing-body combination with a wing with leading edge swept back 63 degrees. Lift, drag, and pitching-moment measurements were made over a range of Mach and Reynolds numbers. Results regarding the general characteristics and effect of Reynolds number are provided.

This report, from the 300 area of the Hanford Plant, May 31, 1956, describes problems and operation of a vacuum system and associated equipment.

The following report describes the electron spectrum of protactinium derived from 23 minute thorium 233 that was produced by neutron capture in stable thorium.

This memorandum provides procedures to be followed in handling uranium in 108-B.

None

From Summary: "A method is given for determining the horizontal tail loads in maneuvering flight. The method is based upon the assignment of a load-factor variation with time and the determination of a minimum time to reach peak load factor. The tail load is separated into various components. Examination of these components indicated that one of the components was so small that it could be neglected for most conventional airplanes; therefore, the number of aerodynamic parameters needed in this computation of tail loads was reduced to a minimum. In order to illustrate the method, as well as to show the effect of the main variables, a number of examples are given. Some discussion is given regarding the determination of maximum tail loads, maximum pitching accelerations, and maximum pitching velocities obtainable."

None

"Investigations have been conducted to determine by means of total-pressure surveys the boundaries of single and twin jets discharging through convergent nozzles into quiescent air. The jet boundaries for the region from the nozzle outlets to a station 6 nozzle diameters downstream are presented for nozzle pressure ratios ranging from 2.5 t o 16.0 and for twin-Jet nozzle center-line spacings ranging from 1.42 to 2.50 nozzle diameters. The effects of these parameters on the interaction of twin Jets are discussed" (p. 1).

Report presenting an investigation in the free-flight tunnel to study the dynamic stability characteristics at low speeds of a winged tow-target model, the wings of which were free to float about a spanwise axis. Results regarding the wing panels fixed rigidly to the fuselage, wing panels hinged to move together, and wing panels hinged independently are provided.

Memorandum presenting an investigation to determine the static directional stability of a fuselage typical of tandem helicopters. The model consisted of a body with an elliptical cross section, a rear rotor pylon which was faired to form a large vertical tail with a very thick airfoil section, and a small horizontal tail mounted at about the midpoint of the height of the vertical tail. Results regarding the stability of the original model, the causes of low directional stability, and tests of some practical modifications of increasing directional stability are provided.

Report presenting a low-speed wind tunnel investigation to determine the relationship between the flap effectiveness and the horizontal and vertical position of a partial-span single slotted flap on a sweptback wing-fuselage combination. Results regarding maximum lift, lift increment, and pitching moment are provided.

Report discusses the results of testing to determine the low-speed longitudinal stability characteristics and spanwise distribution of load of a wing model with the leading edge swept back 63 degrees, an aspect ratio of 3.5, and a large amount of twist and camber. The results are compared to tests of a model of an untwisted and uncambered wing of identical plan form. Measurements of force, pressure-distribution, and comparison of theoretical and experimental span loading are described.

Report presenting an investigation of the effects of several molding conditions on the physical properties of laminates prepared with Fiberglass 181 glass fabric and Bakelite XRS-81 unsaturated-polyester resin. The molding variables included pressure, temperature, and time during both precuring and curing operations. The laminates were tested for several physical properties including resin content, percentage of voids, specific gravity, and flexural strength on the diagonal, both wet and dry.

An investigation was conducted to determine the effects of water injection on the over-all performance of a modified J33-A-27 turbojet-engine compressor at the design equivalent speed of 11,800 rpm. The water-air ratio by weight was 0.05. With water injection the peak pressure ratio increased 9.0 per- cent, the maximum efficiency decreased 15 percent (actual numerical difference 0.12), and. the maximum total weight flow increased 9.3 percent.