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Strontium Program: Quarterly Summary Report, February 24, 1959

Description: From Abstract: "This report is one of a sequence of quarterly reports, each designed to up-date its predecessor beginning with HASL-42, "Environmental Contamination from Weapon Tests." Herein are reported data which have accrued since HASL-51. In particular, the levels of strontium 90 in fallout, milk, tap water, vegetation, and foods are given, based on data available from November 1, 1958 to January 30, 1959."
Date: February 24, 1959
Creator: Hardy, Edward P., Jr. & Klein, Stanley

Investigation of Aerodynamic and Icing Characteristics of a Flush Alternate Inlet Induction System Air Scoop

Description: An investigation has been made in the NACA Lewis icing research tunnel to determine the aerodynamic and icing characteristics of a full-scale induction-system air-scoop assembly incorporating a flush alternate inlet. The flush inlet was located immediately downstream of the offset ram inlet and included a 180 deg reversal and a 90 deg elbow in the ducting between inlet and carburetor top deck. The model also had a preheat-air inlet. The investigation was made over a range of mass-air- flow ratios of 0 to 0.8, angles of attack of 0 and 4 deg airspeeds of 150 to 270 miles per hour, air temperatures of 0 and 25 F various liquid-water contents, and droplet sizes. The ram inlet gave good pressure recovery in both clear air and icing but rapid blockage of the top-deck screen occurred during icing. The flush alternate inlet had poor pressure recovery in both clear air and icing. The greatest decreases in the alternate-inlet pressure recovery were obtained at icing conditions of low air temperature and high liquid-water content. No serious screen icing was observed with the alternate inlet. Pressure and temperature distributions on the carburetor top deck were determined using the preheat-air supply with the preheat- and alternate-inlet doors in various positions. No screen icing occurred when the preheat-air system was operated in combination with alternate-inlet air flow.
Date: July 24, 1953
Creator: Lewis, James P.

Preliminary Results of Cyclical De-Icing of a Gas-Heated Airfoil

Description: An NACA 65(sub 1)-212 airfoil of 8-foot chord was provided with a gas-heated leading edge for investigations of cyclical de-icing. De-icing was accomplished with intermittent heating of airfoil segments that supplied hot gas to chordwise passages in a double-skin construction. Ice removal was facilitated by a spanwise leading-edge parting strip which was continuously heated from the gas-supply duct. Preliminary results demonstrate that satisfactory cyclical ice removal occurs with ratios of cycle time to heat-on period (cycle ratio) from 10 to 26. For minimum runback, efficient ice removal, and minimum total heat input, short heat-on periods of about 15 seconds with heat-off periods of 260 seconds gave the best results. In the range of conditions investigated, the prime variables in the determination of the required heat input for cyclical ice removal were the air temperature and the cycle ratio; heat-off period, liquid water content, airspeed, and angle of attack had only secondary effects on heat input rate.
Date: January 24, 1952
Creator: Gray, V. H.; Bowden, D. T. & von Glahn, U.

Aerodynamic characteristics of a 45 deg swept wing fighter airplane model and aerodynamic loads on adjacent stores and missiles at Mach numbers of 1.57, 1.87, 2.16, and 2.53

Description: Report discussing tests to determine the aerodynamic characteristics of a model of a 45 degree swept-wing fighter airplane and to determine the loads on attached stores and detached missiles. An investigation into aileron-spoiler effectiveness, aileron hinge moments, and the effects of wing modifications of aerodynamic characteristics was also carried out at various Mach numbers. Results are presented, but caution is provided in regards to extrapolating results from the model onto a full-scale aircraft.
Date: June 24, 1958
Creator: Oehman, Waldo I. & Turner, Kenneth L.

Investigation of Noise Field and Velocity Profiles of an Afterburning Engine

Description: From Summary: "Sound pressure levels, frequency spectrum, and jet velocity profiles are presented for an engine-afterburner combination at various values of afterburner fuel - air ratio. At the high fuel-air ratios, severe low-frequency resonance was encountered which represented more than half the total energy in the sound spectrum. At similar thrust conditions, lower sound pressure levels were obtained from a current fighter air craft with a different afterburner configuration. The lower sound pressure levels are attributed to resonance-free afterburner operation and thereby indicate the importance of acoustic considerations in afterburner design."
Date: September 24, 1954
Creator: North, Warren J.; Callaghan, Edmund E. & Lanzo, Chester D.

Wind-Tunnel Flutter Tests at Mach Numbers up to 3.0 of Boeing Wing Models for Weapons System 110A

Description: From Summary: "Flutter tests have been conducted on two low-aspect-ratio wing plan forms under consideration by the Boeing Airplane Company for the 110A weapons system. These configurations had three heavy nacelles near the trailing edge, and flutter tests were made both with and without the nacelles. Up to a Mach number of 3.0 the dynamic pressure required for flutter of a wing with nacelles was generally higher than that of a wing without nacelles."
Date: October 24, 1957
Creator: Levey, G. M.; Tuovila, W. J. & Rainey, A. G.

Interpretation of boundary-layer pressure-rake data in flow with a detached shock

Description: From Summary: "A procedure is presented for determining boundary-layer quantities from pressure-rake data, which include the combined effects of viscous and shock losses. The problem is analyzed using schileren photographs of the shock configuration, the continuity of mass relationship, and the characteristics of the turbulent boundary layer that its outer edge is defined by a rapid change in slope in the Mach-number profiles in the vicinity of the edge."
Date: August 24, 1950
Creator: Luidens, Roger W. & Madden, Robert T.

Use of Truncated Flapped Airfoils for Impingement and Icing Tests of Full-Scale Leading-Edge Sections

Description: From Summary: "In an effort to increase the operational range of existing small icing tunnels, the use of truncated airfoil sections has been suggested. With truncated airfoils, large-scale or even full-scale wing-icing-protection systems could be evaluated. Therefore, experimental studies were conducted in the NACA Lewis laboratory icing tunnel with an NACA 651-212 airfoil section to determine the effect of truncating the airfoil chord on velocity distribution and impingement characteristics. A 6-foot-chord airfoil was cut successively at the 50- and 30-percent-chord stations to produce the truncated airfoil sections, which were equipped with trailing-edge flaps that were used to alter the flow field about the truncated sections. The study was conducted at geometric angles of attack of 00 and 40, an airspeed of about 156 knots, and volume-median droplet sizes of 11.5 and 18.6 microns. A dye-tracer technique was used in the impingement studies."
Date: July 24, 1956
Creator: von Glahn, Uwe H.

An improved approximate method for calculating lift distributions due to twist

Description: Report presenting a method for calculating the lift distribution due to twist which gives a closer approximation than the current Schrenk empirical method and requires about the same amount of computing. The method uses the lifting-line theory and makes use of the lift distribution due to angle of attack and considers the aspect ratio of the wing. Examples are presented for four main types of twist: symmetrical, antisymmetrical, continuous, and discontinuous.
Date: May 24, 1950
Creator: Sivells, James C.

Flight measurements of the wing-dropping tendency of a straight-wing jet airplane at high subsonic Mach numbers

Description: From Summary: "Flight tests were conducted on a straight-wing fighter-type jet airplane to investigate the lateral-control characteristics associated with a wing-dropping tendency encountered at high subsonic Mach numbers. The chief factors found to account directly for the wing-dropping tendency were a progressive reduction in aileron-control effectiveness with increasing Mach number, and an increase in effective dihedral above a Mach number of 0.8 which made the lateral trim particularly sensitive to small changes in sideslip angle."
Date: April 24, 1951
Creator: Anderson, Seth B.; Ernst, Edward A. & Van Dyke, Rudolph D., Jr.

The longitudinal stability, control effectiveness, and control hinge moment characteristics obtained from a flight investigation of a canard missile configuration at transonic and supersonic speeds

Description: A 60 degree delta wing canard missile configuration was flight-tested at the Langley pilotless aircraft research station at Wallops Island, Va. The results include the longitudinal stability derivatives, control effectiveness, drag characteristics, and control-surface hinge-moment characteristics for a Mach number range of 0.7 to 1.45.
Date: November 24, 1950
Creator: Niewald, Roy J. & Moul, Martin T.

Aerodynamic characteristics of a wing with quarter-chord line swept back 60 degrees, aspect ratio 2, taper ratio 0.6, and NACA 65A006 airfoil section : transonic bump method

Description: From Introduction: "This paper presents the results of the investigation of the wing-alone and wing-fuselage configurations employing a wing with the quarter-chord line swept back 60^o, aspect ratio 2, taper ratio 0.6, and an NACA 65A006 airfoil section parallel to the free stream."
Date: February 24, 1950
Creator: Myers, Boyd C., II & King, Thomas J., Jr.