Report with two nomograms presented for rapidly obtaining the compound composition of hydrated limes from the oxide analysis. The general nomogram can be applied to any commercial hydrated lime and gives values accurate to within 0.3 percent while the special nomogram is applicable only to regularly hydrated and highly hydrated dolomitic limes and is accurate to within 0.1 percent.

"The following report is meant to serve a two fold purpose. First, it is the quarterly report of the homogeneous reactor project for the Technical Division of Oak Ridge National Laboratory. Secondly, it is a description and general feasibility discussion of a 200-1000 K.W. pilot model, homogeneous reactor."

An investigation of a 1/18-scale dynamically similar model of the North American B-45 airplane was made to observe the ditching behavior and determine the proper landing technique to be used in an emergency water landing. Various conditions of damage were simulated to determine the behavior which probably would occur in a full-scale ditching. The behavior of the model was determined from high-speed motion-picture records, time-history acceleration records, and visual observations. It was concluded that the airplane should be ditched at the maximum nose-high attitude with the landing flaps full down for minimum landing speed. During the ditching, the nose-wheel and bomb-bay doors probably will be torn away and the rear of the fuselage flooded. A violent dive will very likely occur. Longitudinal decelerations of approximately 5g and vertical accelerations of approximately -6g (including gravity) will be experienced near the pilots' compartment. Ditching braces installed in the bomb bay will tend to improve the behavior slightly but will be torn away along with the bomb-bay doors. A hydroflap installed ahead of the nose-wheel doors will eliminate the dive and failure of the nose-wheel doors, and substantially reduce the motions and accelerations.

A simplified lifting-surface theory that includes effects of compressibility and spanwise variation of section lift-curve slope is used to provide charts with which antisymmetric loading due to arbitrary antisymmetric angle of attack can be found for wings having symmetric plan forms with a constant spanwise sweep angle of the quarter-chord line. Consideration is given to the flexible wing in roll. Aerodynamic characteristics due to rolling, deflected ailerons, and sideslip of wings with dihedral are considered. Solutions are presented for straight-tapered wings for a range of swept plan forms.

From Summary: "A smooth-water-landing investigation was conducted with a small seaplane to obtain experimental wing-bending-moment time histories together with time histories of the various parameters necessary for the prediction of wing bending moments during hydrodynamic forcing functions. The experimental results were compared with calculated results which include inertia-load effects and the effects of air-load variation during impact. The responses of the fundamental mode were calculated with the use of the measured hydrodynamic forcing functions. From these responses, the wing bending moments due to the hydrodynamic load were calculated according to the procedure given in R.M. No. 2221. The comparison of the time histories of the experimental and calculated wing bending moments showed good agreement both in phase relationship of the oscillations and in numerical values."

The following report provides the analysis of a large number of unreported data--taken during a study described in report HW-15230--containing density values obtained for solutions of uranium and nitric acid in tributyl phosphate-carbon tetrachloride solutions.

"A flight test of the Aero jet Engineering Corporation's 7KS-6000 T-27 Jato rocket motor was conducted at the Langley Pilotless Aircraft Research Station at Wallops Island, Va, to determine the flight performance characteristics of the motor. The flight test imposed an absolute longitudinal acceleration of 9.8 g upon the rocket motor at 2.8 seconds after launching. The total impulse developed by the motor was 43,400 pound-seconds, and the thrusting time was 7.58 seconds" (p. 1).

Report presenting a simplified method for obtaining free-flight measurements of damping in roll through the use of rocket-powered models. Initial configurations have been tested for a range of Mach numbers. Results regarding the rolling velocity with two different airfoil sections and damping-in-roll coefficient are provided.

The following report provides results taken from a sodium level indicator developed at Sacandaga using electrical resistance as the principle.

From introduction: During 1948, the Isotope Research and Production Division undertook to obtain small quantities of nearly pure mercury isotopes by electromagnetic isotope separation. The possible use of a mercury isotope of even-numbered mass to establish an international standard of length required an isotopic purity greater than 99 per cent. It, became apparent that this degree of separation could only be achieved by preventing random diffusion of un-ionized mercury which otherwise would contaminate the isotope collectors.

Report discussing an experiment to reinvestigate the spontaneous fission of 48 (Pu-238) in an effort to determine a more accurate value for the spontaneous fission constant that was found in a previous experiment.

Memorandum presenting a calculation of the amount of possible correction for coordinated turns with limited bank angle and level sideslips for a large transport airplane, the C-54D. The results indicate that for all instances from the end of the runway, coordinated turns are the more effective maneuver.

Positive and negative mesons produced in a common target in the cyclotron are received in two photographic plates. In the magnetic field of the cyclotron, negatives are deflected to one plate, positives to the other. The mesons must pass through an absorber before entering the plates in order to be observable.

Report presenting a low-speed wind-tunnel investigation to determine the characteristics of deflectable wing-tip ailerons on an untapered 45 degree sweptback semispan wing. Ailerons with triangular and parallelogram plan forms with a maximum chord of 0.625 wing chord and a flat-plat profile were investigated. The aerodynamic characteristics in pitch and lateral control characteristics are included.

Memorandum presenting a method for varying the mass flow of supersonic inlets with a circular cross section and a central body. The method consists of changing the size of the entering stream tube by means of an inflatable boot on the surface of the central body.

Report presenting comparative tests of the rolling power of plain constant-chord, full-delta, and half-delta ailerons on delta wings with varying degrees of sweepback were tested on rocket-propelled test vehicles. Results regarding the effect of leading-edge sweepback, a comparison of rolling effectiveness, and comparison with theory are provided.

Report presenting the pressure-recovery characteristics of a model with two scoops situated on the aft position of a long forebody and connected through diffusors to a common settling chamber at a range of Mach numbers. The effects of interaction between the flow in the two air-induction systems and of varying the mass flow through the boundary-layer scoops were studied. Results at several different angles of attack are provided.

Report discussing the progress made on a research project for the preparation of ductile zirconium during November 1949.

Report presenting the lift and pitching-moment characteristics of two wings of the same plan form measured over a range of Mach and Reynolds numbers using the wing-flow method. One wing had a symmetrical airfoil section and no twist, while the other was cambered and twisted to support a uniform load distribution at a lift coefficient of 0.25 at Mach number 1.5. A comparison with previous testing is also provided.

"Investigations in the Langley 20-foot free-spinning tunnel of models of five jettisonable nose sections have shown that the airplane nose sections are inherently unstable but can be stabilized by the addition of suitable fins. An empirical criterion has been developed which indicates the fin area required for stabilizing an airplane jettisonable nose section" (p. 1).

Memorandum presenting wind-tunnel tests of a semispan model of a hypothetical supersonic airplane to determine the static longitudinal stability and control characteristics of the airplane throughout the range of subsonic Mach numbers up to 0.95. The model had a long slender fuselage and a wing and horizontal tail of aspect ratio 4 and taper ratio 0.5. Results regarding the force and moment characteristics, wing wake and effective downwash at the horizontal tail, effects of compressibility, and longitudinal characterisitcs with the flaps deflected are provided.

"An investigation was made to evaluate the hydrodynamic qualities of a 0.425-scale model of the Navy XP5M-1 hull, which was installed on a modified Navy J4F-2 amphibian. Longitudinal and directional stability during take-off and landing, low-speed maneuverability, spray characteristics, and take-off performance were investigated. The behavior of the airplane in moderately rough water was also observed. The opinions of three pilots have been correlated with the data" (p. 1).

Report presenting testing of a cambered and twisted wing with constant-chord elevons with a slender fuselage to determine the longitudinal and lateral control from the elevons for a range of Mach numbers. Results regarding lift, drag, pitching-moment, and rolling-moment characteristics for various elevon deflections are provided.

From Summary: "An investigation was conducted in the combustor of a 3000-pound-thrust turbojet engine to determine the altitude performance characteristics of AN-F-58 fuels. Three fuels conforming to AN-F-58 specification were prepared in order to determine the influence of boiling-temperature range and aromatic content on altitude performance. The performance of the three AN-F-58 fuels was compared with the performance of AN-F-48 (grade 100/130) fuel in the range of simulated altitudes from 20,000 to 55,000 feet, corrected engine speeds from 6000 to 12,500 rpm, and flight Mach numbers of 0.2 and 0.6."