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The Aeronautical Engine Laboratory's Containment Evaluation Facility (AELCEF), featuring the government's largest spin chamber, high speed photographic equipment, and impact instrumentation, has been created and has recently become operational. This unique installation is described in detail. The first successful photographs ever taken of the interaction of rotor fragments and a containment ring are presented. Testing techniques and results are discussed. The ultimate goal of the AEL, NASA sponsored, integrated program of theoretical and experimental research work is to provide lightweight containment/control devices that will prevent the fragments of failed turbomachines from injuring personnel and minimize aircraft damage.

On the wing repair is a new concept in jet engine management, rapidly spreading throughout the airline industry. This new approach now requires that maintainability be moved high on the list of design considerations on engines of tomorrow. Some specific maintainability design features are now clearly needed to permit expanding this concept beyond the scope of work now being accomplished. The next commercial engine must have these features.

A new air traffic control system has been designed and is now being implemented, in order to alleviate problems in the present system which have resulted from the constant increase in air traffic since 1950. This new system is commonly called the Beacon System, and is defined in a U. S. National Standard. It automatically provides the air traffic controller with an identified three dimensional radar screen presentation of every properly equipped aircraft within his control area. New ground and airborne equipment is required for this system. The airborne equipment required includes an altitude sensing and digitizing device, a 4096 code transponder, and an antenna.

A fluidic flight control system has been flight tested to develop and evaluate vortex rate sensors, fluidic amplifiers, dynamic shaping techniques, and system accuracy. Discussed are results which have confirmed applicability of conventional control theory and projected high reliability. Also discussed is a stabilization system featuring an electropneumatic servo actuator with variable transfer function and unique characteristics for application to a range of stabilization problems. Recent electronic system studies have shown substantial improvement in reliability, maintainability, size, weight, and cost reduction by use of microelectronic functional modules as alternates to individually-mounted discrete components.

The variable-stability airplane used as in in-flight simulator has been an important and effective research tool in the field of handling qualities requirements for military aircraft. Such a machine is equally well-suited for studies of the general aviation airplane-pilot combination, with the objective of defining optimum and minimum acceptable values of flying qualities parameters for use as design and certification guides.

The slab tail, or stabilator is a comparatively popular design feature of modern business airplanes. Unlike conventional controls, however, there are no rules nor criteria for flutter prevention for slab configurations. The several types of flutter than can occur in a slab tail installation have been studied in the hope that a meaningful flutter criterion can be developed. Unfortunately, too many independent parameters affect the flutter characteristics for this objective to be realized. The influence of these parameters is shown, and some rules are derived which should be useful to the slab tail designer.

Recent engine developments have increased altitude performance of light aircraft. Operation at altitudes above 15,000 ft demands changes in the air operated instrument systems and fuel systems in order to assure dependable operation throughout the new altitude ranges. The first section, on pneumatic systems, deals with the requirements and considerations leading to the conversion from vacuum to pressure operated gyro, autopilot, and de-icer boot systems. The second section, on fuel systems, is intended to aid in the solving of the present fuel systems vapor lock problem. A discussion on aviation gasoline includes a tabulation of most of the hydrocarbons, including the classes of hydrocarbons used in this fuel, together with the vapor pressure, boiling point, and heating value of each. A description of the ASTM distillation tests and the Reid vapor pressure equipment is included, since these characteristics affect the volatility and vapor locking tendency.

The paper discusses the increasing growth in air traffic due to the introduction of the turbine-powered transport and to the growth of general aviation of all kinds. Presented in the paper are some of the Federal Aviation Agency’s development programs for expanding the capability of air route traffic control centers and terminal control facilities, for increasing the usefulness of the navigation and landing aids to more airports, and for increasing airport capacity.

Aircraft cabin pressurization is a means of providing an adequate cabin environment while achieving the performance available from a supercharged engine. The Mooney M22 is a single-engine pressurized four-to-five place aircraft powered by an engine incorporating a small low cost exhaust driven turbosupercharger based on a diesel automotive unit. By means of this turbocharger, the M22 was pressurized and met its performance goals while remaining close to the same economic class as previous conventional single-engine aircraft.

An all-mechanical flight control system is potentially adaptable for high-temperature operation, high structural stiffness, lighter weight, and increased reliability. As part of a continued development program of new control system concepts, a mechanical cascade toroidal servo was tested on the North American Aviation, Inc/Los Angeles Division F-100 flight control simulator. This was the second toroidal servo tested. The improvement over its predecessor was primarily the reduction of pilot operating forces. This mechanical servo incorporated a miniature servo into the input control linkage of the original servo configuration. In this way, the pilot controlled the miniature command or pilot servo and subsequently controlled the power servo with reduced input force.

The relative simplicity of early systems was such that human requirements (skills) were easily interchanged within and between systems. Current complex aerosystems are accompanied by an increased need for closer consideration of the human component. The amounts of information generated and the compressed developmental schedules have led the specialist to rely heavily on his own expertise when existing data are not known to exist or are inaccessible. As such, the input to early identification of requirements and the integration of these requirements into training programs has suffered. In 1963, the Aerospace Medical Research Laboratories and the National Aeronautics and Space Administration, initiated a joint research program to explore, and where possible, develop techniques for handling and processing human factors task data (task analysis/maintenance analysis).

The New Look in TWA training reflects TWA's new DC-9 training program. It is based on the “Instructional Systems Approach” which is a highly-structured, step-by-step, controlled learning system. It is goal and results-oriented and produces most rapid individual learning. The system uses a classroom responder system and other programed-type learning aids. This new approach to training results in 30% reduction in training time coupled with a very high quality of achievement. Industrial training and education are on the brink of a revolutionary change and TWA's DC-9 training program is the beginning of the total change required.

A new method has been developed for estimating the man-hours of labor per flight hour that will be required to maintain many of today's turbojet/fan business airplanes. This method consists of establishing a base manhour per flight hour depending on an airplane's empty weight completely equipped. Then the effect of certain factors that influence this base manhour can be calculated, and the base manhour appropriately adjusted to reflect the total number of man-hours per flight hour. In addition, material costs are estimated. This procedure offers a planned, systematic means by which the maintenance costs of most airplanes in this class can be estimated on an objective basis.

A major step forward in economical near-earth orbital transport capability can be achieved through the “Tip Tank Concept,” based on the development of an integrated launch/re-entry vehicle with a high-degree of reusability. It consists of a long slender vehicle which carries all launch, orbital and re-entry subsystems for subsequent reuse -- plus low cost, lightweight, “throw-away” propellant tanks attached to the sides of the vehicle. With this configuration, it is possible to achieve orbit, utilizing present-day technology, without requiring any additional booster. The integration of the boost propulsion system into the vehicle is a developmental problem which should be solvable utilizing existing booster technology. The operational costs of the tip tank orbital transport system are shown to be approximately one-fourth of the operational costs of a system using an expendable booster such as Titan IIIC with a reusable spacecraft.

A study was made on the metallographic, microchemical and microhardness properties of parallel gap welds and their relationship to each other. The parallel gap welding process is often used to join metals with large differences in their physical properties over wide ranges of energy inputs. The resultant weld microstructures vary over a full spectrum from the so-called brazed joint to a completely fused weld area. It was the purpose of this study to determine the chemical and mechanical variations on a microscale in the weld area to aid in an intelligent interpretation of the microstructure. The bulk of the work was done on gold plated Kovar leads (0.015 × 0.004) welded to nickel ribbon. The main conclusions may be summarized as follows: 1. In the braze type joint the gold plating melts and dissolves metal from the Kovar leads and the nickel ribbon. In the brazed area there are concentration gradients of the elements present in the weld members across the braze.

One of the most critical aspects affecting the ultimate reliability of welded interconnections is the lack of meaningful visual criteria for crosswire joints. In recognition of this, Autonetics has undertaken a comprehensive program to establish the correlation between visual characteristics and metallurgical and mechanical properties of specific wire combinations. Significant numbers of welded interconnections were made using 25 wire combinations and employing welding parameters that would produce cold, typical, and overheated welds. The welded joints were critically examined and classified with regard to useful visual characteristics such as embedment, indentation, filleting, bulging, expulsion, pitting, surface fusion, cracks and voids. Also, metallographic studies were conducted to determine the relationship between internal conditions and joint integrity.

The stresses produced by the epoxy resin during thermal shock may cause rupture of the component-to-ribbon welds in encapsulated welded modules. This investigation develops a mathematical model describing the stresses on component lead wires. Stresses are functions of the temperature-dependent mechanical properties of the epoxy, diameter of an epoxy slug in shear with the component lead wire, and temperature. Thermal stress indexes were established to predict the thermal-shock properties of epoxies. Strain-gage force-voltage transducers, simulating epoxy-encapsulated, cylindrical, electronic components, were used to measure stresses in modules. Good agreement was obtained between experimental data and theoretical results.

In addition to possessing inherent characteristics of operational smoothness, long life, and high reliability, the turboprop engine has the extremely desirable feature of large growth capability in a given frame size. Whereas the reciprocating engine has been growth limited for many years, we can anticipate a large growth in power from today's engines by increasing turbine inlet temperature, improved component efficiencies, and increased engine specific flow. Considerable activity is taking place in the areas of high temperature materials, cooling of turbines and other hot end parts, and on compressor and turbine developments. This paper highlights some of this activity.

Principles of thrust reversing are reviewed along with descriptions of most common types of thrust reversers. Various uses of reversers are discussed and limitations of reversing due to reingestion and other causes are examined. Technical aspects of thrust reverser analysis and testing are related to both static and dynamic performance. Specific uses of reversers on business jets and the resulting performance gains are demonstrated.

The designs of three short takeoff and landing (STOL) commercial transports are described, and their initial and direct operating costs compared with those of conventional high-speed jet transports. STOL performance can be provided at comparable costs by propeller driven aircraft, but at a large sacrifice in cruise speed. STOL performance and comparable cruise speeds result in airplanes with significantly increased costs. Existing airports in the United States are classified by field length, to show the available number of smaller airports which could be used by STOL aircraft. It is suggested that, for business aircraft, the ability to operate from shorter fields does not justify the higher costs, since it may be less expensive to increase runway lengths than to operate significantly more expensive airplanes.