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Computers are a way of life in our society. This is especially true in our aviation transportation industry. This paper examines the direction and impact of automation on the flight deck of transport aircraft. Is technology leading the way to eliminate the human pilot from the flight deck? If not, then there are some issues which need to be addressed in developing the emerging next generation flight deck to permit a safer and more efficient interaction between the human operator and his machine.

Barriers to the more extensive use of advanced composites in heavily loaded structure on commercial transports are discussed from a materials viewpoint. NASA-Langley matrix development activities designed to overcome these barriers are presented. These include the synthesis of processable, tough, durable matrices, the development of resin property/composite property relationships which help guide the synthesis program, and the exploitation of new processing technology to effectively combine reinforcement filament with polymer matrices. Examples of five classes of polymers being investigated as matrix resins at NASA-Langley will be presented, including amorphous and semi-crystalline thermoplastics, lightly crosslinked thermoplastics, semi-interpenetrating networks and toughened thermosets. Relationships between neat resin modulus, resin fracture energy, interlaminar fracture energy, composite compression strength, and post-impact compression strength will be shown.

Following the successful testing of the 25 kWe Space Power Demonstrator (SPD) engine in 1985, a Stirling Space Engine (SSE) technology advancement program was initiated. The program's objective was to advance free-piston Stirling engine/alternator technology sufficiently so that a Stirling engine system may become a viable candidate for space power applications. Evolution of the SSE technology is planned to occur at three different engine heater temperature levels: 650, 1050, and 1300 K. These temperatures define three phases of technology development with the first phase involving the 650 K SPD engine. Technology development of the 650 K engine and preliminary design of the 1050 K engine will be discussed in this paper.

A new laboratory scale coalescence test, designated the Exxon Coalescence Test or ECT, was developed which allows the water coalescence of aviation fuels to be investigated under controlled conditions. The ECT is essentially a small-scale filter/separator incorporating both a coalescer and separator stages and operating at a 800-fold reduction in flow rate from a full-scale filter/coalescer element. The effect of a number of commercial fuel additives, antioxidants, corrosion inhibitors, anti-icing additives, and static dissipator additives, on water coalescence in JP-5 aviation fuel were determined using the ECT. Single Element Tests, conducted using full-scale military filter/coalescer elements, validated the results from the ECT. The ECT promises to be an effective tool for further investigation of the factors affecting water coalescence in filter/separators.

The flow fields encountered by jet- and fan-powered vertical/short takeoff and landing (V/STOL) aircraft when hovering in ground effect are reviewed and their effects on the aerodynamic characteristics are discussed. The ground effects considered include the suckdown generated by the flow from a single nozzle, the fountain effects generated by multiple-nozzle configurations, and the additional suckdown associated with the fountain flow generated by multiple-nozzle configurations. Our current understanding of the flow fields involved and the capability and limitations of available methods for estimating the effects of ground proximity are reviewed and the areas where additional work is needed are discussed.

The paper describes the basic mechanisms of Hot Gas Recirculation (HGR) in V/STOL aircraft, and some ways to assess and control it. Severe HGR can cause large thrust losses, or even compressor stall; avoidance of excessive HGR is therefore critical for safe V/STOL operation, especially when a high-specific-thrust engine is used to give the aircraft supersonic capability. Near the ground, jet-induced lift losses increase, but can be offset by upward forces resulting from “fountain” flows. The fountain is a powerful potential HGR source; the ground jet can also be a source of HGR through its interaction with headwind, aircraft motion and buoyancy. Some practical design principles to limit the resulting HGR are discussed. The full scale data base on HGR is limited, and it is therefore necessary to rely heavily on model testing. Scaling principles are briefly surveyed; it is shown that it is not possible to achieve similarity in all test parameters at once.

Current powered lift aircraft studies include those which propose to utilise high specific thrust engines vectored for vertical landing. In ground proximity the high pressure, high temperature, exhaust plumes create a hostile environment for the aircraft, ground crew and equipment, and the landing platform. The potential difficulties have re-awakened research interest in the fields of: Ground surface erosion. Near field/mid field noise. Upwash impingement on the aircraft. Ground sheet temperature and velocity. This paper describes the physical nature of these problems, discusses some of the perceived operational difficulties and makes suggestions for further work, under each of the above headings. Ground proximity also creates other problems; notably ingestion of hot gas into the engines inlets and jet re-circulation induced forces and moments on the aircraft, but these are outside the scope of this paper.

This article presents work performed at the Naval Air Engineering Center involving V/STOL Aircraft ground flows. Exhaust flows are directly related to aircraft size (thrust level) and propulsion system size (disk loading). A brief commentary on ground flow phenomena through the full range of disk loading is given. Major discussion is devoted to the narrower band of disk loading attendant with high performance V/STOL Aircraft. In particular, gas velocities and temperatures in the ground flow surroundings, and characteristics of pervasiveness are described. Heat transfer into a uniform structure has been calculated for concrete, poly/resin, asphalt, aluminum, and steel. Resultant surface and internal temperature distributions are shown. The Influence of engine exhaust temperature, height above ground, and heating time is illustrated. Jet engine exhaust impingement tests of refractory concretes, asphalt, and aluminum have been conducted and compared with heat transfer computations.

The aerodynamics of the STOL aircraft can experience significant changes in proximity to the ground. A review of the existing data base and methodologies has been made and the results of that review are presented in this paper. The existing data show that in ground proximity the STOL aircraft will generally experience a reduction in the lift component regardless of the lifting configuration. Those configurations with integrated power and lift systems will have an additional effect of ground induced aerodynamic changes. This paper will discuss the existing data base and the deficiencies of that data base.

This paper describes a low cost flight test program and presents the results for evaluating the performance of the Ball-Bartoe JETWING upper surface blown powered lift aircraft with and without the thrust augmenting ejector installed. The program included a ground test series for thrust calibration by dynamometer and by measuring the velocity profile with laser velocimeter followed by performance flight testing to obtain lift coefficient vs. angle of attack and lift coefficient vs. excess thrust coefficient. Stability and handling characteristics were also evaluated. Flight test results when compared with wind tunnel data generally showed good agreement although the lift curve slope obtained by flight test is somewhat less than that from wind tunnel primarily testing because of inaccuracies involved in measuring angle of attack in flight.

The development of the de Havilland Aircraft of Canada (DHC) augmentor-wing powered-lift concept is briefly reviewed from the mid-1960's to the present day. A parallel DHC research program over the period from the mid-1970's to the present day has developed a very thick high speed compound or multi-foil wing section for the Augmentor-Wing concept. This program proved more successful than initially anticipated and has led to the development of both blown and unblown wing sections up to 24% thickness-chord with CL (cruise) greater than 0.6 and design cruise Mach numbers around 0.7, two-dimensionally. This research is also reviewed. More recently, design studies have shown that integration of these technologies leads to very efficient transport aircraft which can achieve Ultra-Stol capability with only the thrust installed for cruise.

Tactical Airlifters in the battlefield of the future will be required to operate on unprepared or damaged runways in all weather conditions without navigational or landing aids. Lockheed is addressing technologies required for these missions in an independent research and development program using a highly modified commercial C-130 aircraft as the technology integration focal point - a “Flying Laboratory.” The HTTB Program addresses the major technology areas of advanced short takeoff and Sanding, survivability, advanced cockpit, and electronic systems. The Program goal is to develop systems to support autonomous operations into a 1500-foot landing area, up to and including a 50-foot obstacle at the runway threshold.

A supersonic STOVL fighter aircraft aerodynamic research program is being conducted at NASA Ames Research Center. The research focuses on technology development for this type of aircraft and includes generating an extensive aerodynamic database and resolving particular aerodynamic uncertainties for various twin- and single-engine aircraft concepts. Highlights of the results from this program are presented. The highlights include propulsion-induced effects on the aircraft drag, prediction capabilities, volume integration for minimizing drag, and wave drag and aerodynamic efficiency comparisons. Results indicate that estimated STOVL fighter performance is roughly comparable to the performance of modern conventional fighters in terms of wave drag and aerodynamic efficiency.

The quiet STOL research airplane (ASKA) was developed as a research aircraft that would provide high levels of STOL performance at low levels of community noise. The ASKA is a C-l tactical transport, modified to incorporate a USB type propulsive-lift system powered by MITI/NAL FJR71O/600S and equipped the BLC and the SCAS. During first 2 years of flight research, the flight tests have been devoted to confirm the initial airworthiness and system function except the BLC system. But all these tests have been limited to the shallow USB flap configuration without the BLC, because of cracks appeared in the engines. The major subjects in this period were as follows; evaluation of newly developed engine, actual proof of structure, confirmation of different avionics systems and the SCAS, and documenting of fundamental flying quality and performance. We have the flight program that the effort will be concentrated on documenting the STOL characteristics in the low speed region.

THE ROYAL AIR FORCE was the first military organisation to deploy a fixed-wing vertical/short take-off and landing aircraft - the British Aerospace Harrier. This paper describes the Royal Air Force's concept of operations for its current force of Harrier GR3s and sets out the advantages of the new Harrier GR5. Finally, it discusses the future of V/STOL with particular regard to Royal Air Force interest in the proposed Advanced Short Take-Off and Vertical Landing aircraft.

This paper describes a combined display and control system to provide high-precision manual landing flare and touchdown, and presents the results of a preliminary flight evaluation using the NASA Quiet Short-Haul Research Aircraft (QSRA). A head-up display presents flare commands to the pilot, who executes a simple, repeatable nominal flare maneuver. Height and height rate errors relative to the desired trajectory are fed back to a low-authority (±0.05g) direct-lift-control system that drives spoilers and throttles so as to null the errors resulting from gusts and pilot deviations. This integrated cockpit display and closed-loop control constitutes a trajectory augmentation system that extends the QSRA flight control from augmentation of attitude, flightpath angle, and airspeed (previously reported) to augmentation of the trajectory itself. The pilot can easily over-ride the low-authority closed-loop control, and a monitored simplex system is adequate for safely.

This paper reviews ejector development at DHC over the past 25 years and focuses on the features proposed for the E7 wind tunnel model. The E7 aircraft is a STOVL project study design by General Dynamics, Fort Worth, which utilizes lift ejector technology developed by DHC (Ref. 1). Efforts to maximize thrust augmentation ratio within the packaging constraints of typical STOVL aircraft configurations are described. Experimental results from antecedents of the E7 ejector are presented together with the latest results from full-scale tests at Lewis Research Center, NASA. The major geometrical parameters are described and their influence on thrust augmentation evaluated. Various nozzle types are discussed. Performance is compared with theoretical trends derived from global compressible theory. A brief look at the installation aerodynamics of a pair of chordwise ejectors, in hover, completes the paper.

The Quiet Short-Haul Research Aircraft (QSRA), designed for flight investigation into powered-lift terminal area operations, first flew in 1978 and has flown 600 hours since. This report summarizes QSRA research since 1981. Numerous aerodynamic flight experiments have been conducted including research with an advanced concept stability and control augmentation and pilot display system for Category III instrument landings. An electromechanical actuator system was flown to assess performance and reliability. A second ground-based test was conducted to further evaluate circulation-control-wing/upper-surface-blowing performance. QSRA technology has been transferred through reports, guest pilot evaluations and airshow participation. QSRA future research thoughts and an extensive report bibliography are also presented.

Directing the exhaust of a turbojet engine through an ejector pump can significantly increase the jet thrust. This paper is a review of recent advances in the development of thrust augmenting ejectors for VSTOL aircraft. Progress in developing a theory of ejector operation, and related efforts in analysis and prediction will be summarized. Studies of turbulent mixing and duct design which have led to improvements in ejector performance will also be described. Finally, research problems of current interest and the likely direction of future airplane programs will be discussed.