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The new rare-earth sammarium-cobalt magnets are revolutionizing electromechanical actuation design to the extent that power-by-wire can be a legitimate follow-on to fly-by-wire. These new magnets coupled with innovative design techniques which feature direct interface with fly-by-wire are creating electromechanical actuator designs that are highly competitive to hydraulic actuators in terms of weight, space, and performance. A major promise of these new electromechanical actuators is to permit unification of total secondary power systems under a single medium, electrical.

Octane number requirement mapping of an 8:1 CR Ford 2.3 liter engine was carried out under dynamic conditions at 1″, 3″ and 6″ vacuum accelerations. Equations were developed relating octane number requirements to engine rpm, manifold vacuum, spark advance, air-fuel ratio, and exhaust gas recirculation rate. These equations, together with Ford's extensive emissions and fuel consumption data, were used to determine whether octane number requirements constitute a limiting constraint in the optimization of engine-vehicle systems. In addition, steady-state and dynamic octane number requirements were compared at 9:1 CR. The results indicate that dynamic octane number requirements cannot be predicted from limited steady-state requirements data.

Steady state engine mapping data were obtained from a 400 CID, V-8 spark ignition engine at compression ratios (CR) of 9.3 and 8.0. Data were obtained for seven steady-state speed-load conditions and also for one transient condition to determine the effect of compression ratio on fuel consumption at various exhaust emission levels. These speed-load points were selected to represent engine operating points during the CVS-H cycle. Earlier results at high speed-load conditions indicated that lower fuel consumption could be achieved with the 9.3 CR configuration, even when emission constraints for HC and NOx were imposed. Also at the low speed-load conditions, at high or unconstrained HC levels, fuel consumption was found to be lower at 9.3 CR; but HC emissions could not be reduced as far at 9.3 CR as at 8.0. Finally, all of the speed-load points were combined in time-weighted cycle simulations to compare the two compression ratios by several emissions and fuel consumption criteria.

The optimization on an engine-three way catalyst-vehicle system for best fuel economy under the constraints of emissions and driveability, has been studied for a smaller passenger car with 1.6 litter 4 cylinder engine. Full utilization of a computer was intended for the accumulation of basic data and a search for optimum calibration. An automatic Engine Test System ( AETS ) was developed. The optimum calibration was calculated for the engine-vehicle system with three-way catalyst based on the optimal control theory, and was implemented on an actual vehicle by an engine controller in which a 16 bits microprocessor was used. The results showed good agreement.

Engine-fuel relationships of the Ford PROCO stratified charge engine have been examined. The test program was conducted in three phases to assess the interrelationships between exhaust emissions, fuel economy, octane requirement, and fuel properties in an experimental, research, single cylinder, stratified charge PROCO (programmed combustion) engine. In Phase I, tests were conducted at a steady-state speed-load condition to determine the effect of engine calibration parameters on emissions and fuel economy after an initial evaluation of engine operation with three different ignition system configurations. A dual ignition system produced reliable, misfire-free operation with the dilute mixtures and high EGR rates tested. In Phase II, five fuels with significantly different volatility properties and composition were tested to determine their effect on emissions and fuel economy of the PROCO engine.

Unregulated emissions, i.e., emissions which are not currently regulated by EPA, have been measured from a 7.5 L (460 CID) PROCO engine powered vehicle operating at 50 kph on a chassis dynamometer. A dilution tube was used. Emphasis was on particulate emissions, which were characterized physically and chemically. A comparison is made to recent similar measurements on Diesel and conventional gasoline powered vehicles.

Aircraft trailing vortices are one of the principal factors affecting aircraft arrival and departure rates at airports. Minimization of the trailed vortex strength would allow reduction of the present spacing requirements and full utilization of advances in automatically aided landing systems. For several years, NASA has been conducting an intensive in-house and contractual research effort involving theoretical and experimental studies of various wake vortex minimization techniques. The results of these studies are briefly described herein.

Fuel-conservative procedures have been investigated using real-time air traffic control simulations linked to two piloted simulators. The fuel-conservative procedures studied were profile descents and two types of landing approaches. The investigation determined the effect of these procedures on the ATC system and terminal area capacity. It examined the mixing of aircraft executing fuel-conservative approaches with those executing conventional approaches. The results indicate a systems fuel savings for the landing approaches under all tested conditions except at, or near, maximum system capacity. Also, there is a fuel savings and reduced controller workload for the profile descent procedures.

Did you mean what I thought you meant when you said what I thought you said? This question is the essence of a phenomenon called a “FALSE HYPOTHESIS”. A false hypothesis could be an underlying theme of many pilot error accidents. The possibilities for occurrence in the cockpit must be considered by the pilot and the designer.

The airport planner working with airports at high elevations is faced with existing conditions that require careful consideration. Of primary concern is the safety of airspace procedures in mountainous areas which are critical and difficult. Very few sites have good obstruction clearances for aircraft approaching the runway or taking off. Another serious consideration is that construction in these areas is expensive, for the airport and for the facilities that are required for it's operation, such as highways, power lines, fuel lines and water supply. This paper describes the experiences and approach of the authors and their associates in undertaking the site selection and master planning for future airport development at Quito, Ecuador which is at 2,812 meters elevation. The city's airport has experienced major impacts from commercial aviation growth in the last two decades. As commercial aircraft traffic increases, the airport is becoming overtaxed physically and environmentally.

The unique operating capabilities of the helicopter have enabled it to become a positive growth sector of the aviation industry. It must be questioned whether the manufacturers and National Authorities are providing the helicopter operator with the right aircraft and the correct regulatory controls to maximise this growth. Modern technology rotorcraft could replace the short haul jet airliner on stages up to 500 miles, replacing expensive and complex airports with simple and efficient heliports. Helicopters incorporating new rotor designs could help reduce the environmental noise pollution problems associated with aviation, especially for those areas close to take-off and landing paths. The technology, the skills, and the market are available - surely they must not be wasted.

The helicopter's unique ability to transport large work crews and heavy equipment to remote areas quickly, cheaply, and efficiently will become increasingly important and useful as easily accessible resources are depleted. The introduction of large helicopters into operation will result in increased capabilities and expanded application of helicopter transport. Because costs prohibit certifying a new large helicopter, updating and adapting existing machines, developed under military programs is a very desirable approach. The Boeing Vertol CH-47 “Chinook” helicopter is a prime candidate for this opportunity due to its successful history in the U.S. Army as well as with foreign users.

The new generation of helicopters which will see operational use in the 1980's will provide significantly greater productivity and lower operating costs than their predecessors. Both of these improvements result from technological advances made during the past decade. These advances and the methods used to achieve them are described in detail. Included are the new technology manifested in main and tail rotor blade and head design, composite structures, vibration reduction, and aerodynamic drag. The resulting payoffs are traced to productivity and operating cost benefits, with figures relating to Sikorsky's new S-76 as an example.

The growth in air freight traffic can be attributed to the increasive number of service and light industries of the United States' economy. Fast and reliable deliveries of small and time sensitive documents are much in demand. The inflation spiral and the thin density of operations, however, have resulted in the discontinuation of air passenger services into small communities. Air freight forwarding, which is an adjunct to passenger service, has been sharply curtailed as a result. A solution to the problem appears to be an all air cargo airline that can operate its own vehicles in a streamlined fashion and can achieve the economy of scale by consolidating traffic. While there are attempts to do this, Federal Express Corporation is an example of innovation. Door-to-door service is provided through its fleet of Falcon jets and pickup/delivery trucks. Traffic is bundled up from thin density markets via a concentrated operation in Memphis.

The advantages of ground-based simulation relative to flight test are discussed. These include: lower cost, better control of environmental factors, ability to investigate hazardous situations, completely known dynamics, comprehensive measurements and measurement accuracy, repeatability, ease of making changes and comparisons, and early availability. The disadvantages and many practical problems are associated with modeling errors and unrealistic pilot behavior. The modeling features discussed are: the aerodynamic model, modeling of atmospheric disturbances, ground effects, landing gear dynamics, sampled-data effects, and extrapolation to very low speeds. Unrealistic pilot behavior results from distortions in the visual, motion, and aural cues, and from differences in psychological factors. Practical problems in each of these areas are discussed.

The certification of an aircraft has progressed from demonstrations which were performed entirely upon the first-flight article to those in recent years which apply varying degrees of ground-based test facilities (simulators). The extent of these test facilities has been influenced by the complexity of the aircraft and the aircraft systems, the individual manufacturer's development philosophy and the funding allocated to simulation. This paper, based primarily on the development and certification of the Lockheed L-1011, concludes that increased simulation to show compliance is not only possible but in many instances is cost effective as well. This conclusion is based on a review of the requirements set down by FAR 25, the methods used to certify the L-1011 and the relative costs of compliance demonstration by flight testing and simulation. The present industry trend towards the derivative aircraft is making the argument for increased simulation for certification even stronger.

The process of obtaining FAA Certification of helicopters is time consuming and very costly. By using analytic flight dynamic modeling techniques to predict the flight characteristics of new aircraft, the amount of flight testing required for certification may be reduced. Sikorsky Aircraft undertook in 1977 a program which was aimed at setting the stage for future reductions in the amount of flight testing required for helicopter certification. This program was initiated by exposing FAA personnel to the makeup of the analytic program and the correlation obtained with flight test data using this program. Subsequently, the analytic model, “Gen Hel,” was used to predict S-76 flight characteristics so as to provide apriori data for correlation with the flight data generated during certification testing.

Aviation is viewed as a growth industry with technological advances continuing well into the 21st Century. While growth constraints to air transportation such as economics, energy, and congestion are very real, technical improvements in dependability, efficiency, and speed will tend to counteract them. Certain NASA activities which impact long-haul (greater than 500 miles) and far-term air transports (1990's and beyond) are discussed. The keys to improved dependability are congestion relief and all-weather operations. Progress in all-weather 4-D navigation and wake vortex attenuation research is discussed and the concept of time-based metering of aircraft is recommended for increased emphasis. The far-term advances in aircraft efficiency are shown to be skin-friction reduction and advanced configuration types. The promise of very large aircraft - possibly all-wing aircraft - is discussed, as is an advanced concept for an aerial relay transportation system.

On the assumption that further building of large airports will be denied the paper examines the scope for upgrading the efficiency of existing terminals by the addition of short runways within their boundaries. It is found that runways of about 2000 feet in length can frequently be placed so as to avoid interference with existing flight paths, particularly when account is taken of the compact maneuvering capability of typical short-field aircraft. This blend of land availability and existing airplane types is proposed as an economically viable near term relief to terminal congestion.