Describes the damage grasshoppers cause to crops, how to identify different species, how they develop, and where and how they live. With this information as a background, the final section describes how to control them.

From Forward: "This report describes the present conceptions of the Experimental Breeder Reactor-II as well as the safety procedures and precautions which are currently anticipated for its operation."

Report describing the fabrication of Doppler Helices, which were 1/8 inch diameter x 12 foot long uranium core completely enclosed within a thin metal jacket and wound into a spring or helix shape.

Memorandum presenting a study of the performance of swirl-can combustor elements for an experimental short-length turbojet combustor utilizing hydrogen fuel at high-altitude operating conditions. Fuel was injected into each element through a tangential, sonic orifice that created a swirling fuel-air mixture within each element. Results regarding combustor blowout, combustion efficiency, outlet temperature distribution, and preliminary performance of multielement combustor are provided.

Memorandum presenting a turbojet engine with a two-stage turbine operated with pentaborane fuel continuously for 11.5 minutes at a simulated altitude of 55,000 feet at a flight Mach number of 0.8. The engine incorporated an NACA combustor designed specifically for use with pentaborane fuel. Results regarding oxide formation and deposition, engine operating point, effect of oxide deposits on component performance, effect of oxide deposition on overall performance, and some operational comments are provided.

Report presenting an investigation of the ejection release characteristics of the MB-1 rocket from the missile bay of a model of the Convair F-106A airplane with its fin tips retracted at a simulated altitude of 18,670 feet. Successful ejections of the rocket were made at supersonic speeds by applying a combination of ejection velocity and nose-down pitching moment at release.

From Summary: "A statistical study is made of icing data reported from weather reconnaissance aircraft flown by Air Weather Service (USAF). The weather missions studied were flown at fixed flight levels of 500 millibars (18,000 ft) and 700 millibars (10,000 ft) over wide areas of the Pacific, Atlantic, and Arctic Oceans. This report is presented as part of a program conducted by the NACA to obtain extensive icing statistics relevant to aircraft design and operation. The thousands of in-flight observations recorded over a 2- to 4-year period provide reliable statistics on icing encounters for the specific areas, altitudes, and seasons included in the data."

Report discussing the performance of an experimental quarter-sector annular combustor at conditions simulating supersonic flight of a cooled-turbine engine, as well as 20 different modification to the design. The final configuration was found to show no structural failures and little or no warping of liner parts after 40 hours of operation.

Memorandum presenting an investigation of performance estimates of aircraft nuclear propulsion (ANP) systems. This paper includes a relation of current estimated ANP performance to the future requirements that nuclear propulsion systems will be required to meet.

Report presenting data to determine the component and overall engine performance up to an altitude limit for the J71-A-11 (600-B36) turbojet engine. Engine operation using JP-4 fuel at Mach number 0.8 was satisfactory up to an altitude of about 60,000 to 65,000 feet, and engine operation with marginal combustion stability was maintained to an altitude of about 80,000 feet. Results regarding the altitude operating limits, component performance, overall engine performance, contribution of individual component losses to overall engine performance losses, exhaust-nozzle-area requirements, and altitude performance at rated engine conditions are provided.

Report presenting an investigation of the ejection release characteristics of the MB-1 rocket from the missile bay of a Convair F-106A airplane. Results regarding pitching moment, ejections, release conditions, and missile trajectory are provided.

"Static tensile test results are presented for specimens of 2014-T6, 2024-T4, 6061-T6, and 7075-T6 aluminum alloy containing fatigue cracks. The results are found to be in good agreement with the results reported for similar tests from other sources. The results indicate that the presence of a fatigue crack reduced the static strength, in all cases, by an amount larger than the corresponding reduction in net area; the 6061-T6 alloy specimens were least susceptible to the crack and the 7075-T6 alloy specimens were most susceptible" (p. 1).

"The theory of cascades, made up of a series of flat plates placed one behind the other, is extended to the case where the impinging stream is not uniform, and the deduced properties of this cascade-flow are then applied to the study of the wall interference between such as cascade-like boundary and a vortex-source type of singularity. It is shown that the induced velocities, produced by the presence of such a wall, are equal to what is obtained by action of a suitably chosen 'reflected' singularity situated on one side of the wall, together with the action of another suitably chosen 'transmitted' singularity placed on the other side" (p. 1).

"An investigation has been completed in the Langley 20-foot free-spinning tunnel on a l/18-scale model of the Ryan X-13 airplane to determine its spin, recovery, and tumbling characteristics, and to determine the minimum altitude from which a belly landing could be made in case of power failure in hovering flight. Model spin tests were conducted with and without simulated engine rotation. Tests without simulated engine rotation indicated two types of spins: one, a slightly oscillatory flat spin; and the other, a violently oscillatory spin" (p. 1).

"An investigation has been conducted in the Langley Unitary Plan Wind tunnel to determine the static stability and drag characteristics of a 1/10-scale model of the AVCO booster vehicle. The tests were made at a constant Reynolds number, based on maximum nose diameter, of 1.09 x 10(exp 6)6 at Mach numbers of 1.60 and 2.00" (p. 1).

A full-scale turbojet engine was operated with pentaborane fuel continuously for 22 minutes at conditions simulating flight at a Mach number of 0.8 at an altitude of 50,000 feet. This period of operation is approximately three times longer than previously reported operation times. Although the specific fuel consumption was reduced from 1.3 with JP-4 fuel to 0.98 with pentaborane, a 13.2-percent reduction in net thrust was also encountered. A portion of this thrust loss is potentially recoverable with proper design of the engine components. The boron oxide deposition and erosion processes within the engine approached an equilibrium condition after approximately 22 minutes of operation with pentaborane.

Report presenting an investigation conducted with trimethyl borate azeotrope and pentaborane fuels in a turbojet combustor. The primary purposes of the study were to determine the effect of boron oxide deposits on the turbine-nozzle area, combustor pressure loss, temperature distribution, and combustion efficiency. Three distinct boron deposit patterns were noted in the investigation.

Report presenting an investigation in the high-speed 7- by 10-foot tunnel to determine some effects of tail height and wing plan form on the static longitudinal stability characteristics of a complete, small-scale model at high subsonic speeds. It had both a low-tail and high-tail position. Results regarding the lift and drag characteristics and longitudinal stability characteristics are provided.

Report presenting a description of a new blade series designed to operate at near choking inlet Mach numbers and to have near maximum critical Mach numbers by employing high aerodynamic loading of the profiles in the leading-edge region. Results regarding aerodynamic characteristics and prediction of high-speed performance are provided.

From Summary: "Charts are developed for the analysis of flow in a whirling constant-diameter duct. These charts permit the determination of the duct-exit Mach number, or the Mach number at any point along the duct, for practical ranges of duct-inlet Mach number, duct-tip Mach number, friction factor, ratio of ambient temperature to duct-flow total temperature, ratio of duct-tip radius to duct hydraulic diameter, and heat conductivity through the duct wall and surrounding material. The method of using the charts is illustrated through the computation of a sample problem."

Report presenting calculations of the lift and moment responses to penetration of sharp-edged traveling gusts for wings in incompressible and supersonic two-dimensional flow, for wide delta and rectangular wings in supersonic flow, and for very narrow delta wings. The results of the calculations indicate that the forward speed of the gusts has a large effect on the lift- and moment-response functions.

Report presenting a study of the use of a magnetic field to control the motion of electrically conducting fluids. Results indicated that the skin friction and heat-transfer rate are reduced when the transverse magnetic field is fixed relative to the plate and increased when fixed relative to the fluid.

Note presenting an evaluation of the boundary layer along the walls of a shock tube, which induces pressure and velocity gradients within the core of potential flow.

Note presenting a study to determine if common aircraft metals produce friction sparks capable of igniting combustibles that might be spilled in an airplane crash. Samples of aluminum, titanium, magnesium, chrome-molybdenum steel, and stainless steel were dragged over concrete and asphalt runways while a combustible mixture of gasoline, JP-4 fuel, kerosene, or preheated oil was sprayed around the sample.