and Reliability Jun. 1990 P 1-34 IAA as A90-20608 Previously announced in N91-10042 (For primary document see 01-05) Copyright Avail: NTIS HC/MF A05; Non-NATO Nationals requests available only from AGARD/Scientific Publications Executive An analysis of the UK CAA's world wide helicopter accident data indicates that transmissions accounted for 22 percent of potentially airworthiness related accidents in civil helicopters of more than 4550 kg gross weight. An evaluation is made of design and technology advancements over the last decade which should benefit helicopter transmission safety and reliability. These encompass improved steels with superior fatigue performance, S/N curve refinement, computer aided design analysis systems, CAD/CAM, improved lubricants and filtration systems, and expert systems retaining a collective memory with regard to design practices' relationship to service experience. N91-10044# Akron Univ., OH. DRIVE SYSTEM LIFE AND RELIABILITY E.R. M. Savage In AGARD, Rotorcraft Drivetrain Life Safety and (For primary document see Jun. 1990 p 35-71 Reliability N91-10042 01-05) Copyright Avail: NTIS HC/MF A05; Non-NATO Nationals requests available only from AGARD/Scientific Publications Executive Fuel efficiency is an important objective in aircraft propulsion. In design, the requirements of light weight and high reliability conflict. Designers use highly stressed, high quality alloy steels in the major load bearing components to resolve the conflict. One estimate for the service needs of a drive system comes from its life and reliability models. The design objectives of long life between repairs and high reliability are design goals. The statistics of drive system life and reliability are discussed. The statistics develop reliability models for repair prediction. The modes of failure which are the basis for these models are also discussed. Coverage of the two parameter Weibull distribution model for component and system life is detailed. Similar coverage is made of the Miner Palmgren load-life model. Based on this model, the theory of mission spectrum averaging is presented. Mission spectrum averaging determines the equivalent constant load which has the same life as the mission spectrum. Also the component life and reliability models for bearings and gears are described. On-board monitoring systems are described. Estimates of the drive system failure rate and replacement needs are still essential at the design stage. E.R. N91-10045*# National Aeronautics and Space Administration. Ames Research Center, Moffett Field, CA. ROTOR SYSTEMS RESEARCH AIRCRAFT RISK-REDUCTION J. Brent Wellman Washington Aug. 1990 356 p A shake test and an extensive analysis of results were performed to evaluate the possibility of and the method for dynamically calibrating the Rotor Systems Research Aircraft (RSRA). The RSRA airframe was subjected to known vibratory loads in several degrees of freedom and the responses of many aircraft transducers were recorded. Analysis of the transducer responses using the technique of dynamic force determination showed that the RSRA, when used as a dynamic measurement system, could predict, a posteriori, an excitation force in a single axis to an accuracy of about 5 percent and sometimes better. As AIRCRAFT DESIGN, TESTING AND PERFORMANCE the analysis was broadened to include multiple degrees of freedom for the excitation force, the predictive ability of the measurement system degraded to about 20 percent, with the error occasionally reaching 100 percent. The poor performance of the measurement system is explained by the nonlinear response of the RSRA to Author vibratory forces and the inadequacy of the particular method used in accounting for this nonlinearity. N91-10046# Oak Ridge National Lab., TN. Transportation Analysis. Center for ENERGY EFFICIENCY IMPROVEMENT POTENTIAL OF David L. Greene Jun. 1990 42 p (DE90-014767; ORNL-6622) Avail: NTIS HC/MF A03 Aircraft are second only to motor vehicles in the use of motor fuels. Furthermore, air travel is growing twice as fast as highway travel. Clearly, the importance of energy use by commercial aircraft will continue to increase. Since 1970, air travel has more then tripled, but the growth of fuel use has been restrained by a near doubling of efficiency, from 26.2 seat miles per gallon (SMPG) in 1970 to about 49 SMPG in 1989. This paper explores the potential for future efficiency improvements via the replacement of existing aircraft with 1990's generation and post 2000 aircraft incorporating advances in engine and airframe technology. Today, new commercial passenger aircraft deliver 50 to 70 SMPG. New aircraft types scheduled for delivery in the early 1990's are expected to achieve 65 to 80 SMPG. Industry and government researchers have identified technologies capable of boosting aircraft efficiencies to the 100 to 150 SMPG range. Under current industry plans, which do not include a post-2000 generation of new aircraft, the total aircraft fleet should reach the vicinity of 65 SMPG by 2010. A new generation of 100 to 150 SMPG aircraft introduced in 2005 could raise the fleet average efficiency to 75 to 80 SMPG in 2010. In any case, fuel use will likely continue to grow at from DOE 0.8 percent/y to 1.8 percent/y through 2010. N91-10047*# Georgia Inst. of Tech., Atlanta. Aerospace Engineering. School of NONLINEAR FEEDBACK CONTROL FOR HIGH ALPHA (NASA-CR-186545; NAS 1.26:186545) Avail: NTIS HC/MF A03 CSCL 01C Analytical aerodynamic models are derived from a high alpha 6 DOF wind tunnel model. One detail model requires some interpolation between nonlinear functions of alpha. One analytical model requires no interpolation and as such is a completely continuous model. Flight path optimization is conducted on the basic maneuvers: half-loop, 90 degree pitch-up, and level turn. The optimal control analysis uses the derived analytical model in the equations of motion and is based on both moment and force equations. The maximum principle solution for the half-loop is poststall trajectory performing the half-loop in 13.6 seconds. The agility induced by thrust vectoring capability provided a minimum effect on reducing the maneuver time. By means of thrust vectoring control the 90 degrees pitch-up maneuver can be executed in a small place over a short time interval. The agility capability of thrust vectoring is quite beneficial for pitch-up maneuvers. The level turn results are based currently on only outer layer solutions of singular perturbation. Poststall solutions provide high turn rates but generate higher losses of energy than that of classical sustained Author solutions. Army/NASA Aircrew-Aircraft Integration (AAAI) Program that is intended to bridge an existing gap between Government developers (including contractors) and outside organizations who are potential users of products and services developed by the AAAI Program. Currently in its sixth year, the Program is experiencing considerable pull from industry and other government organizations to disseminate products. Since the AAAI Program's charter is exploratory and research in nature, and satisfying proper dissemination requirements is in conflict with the rapid prototyping approach utilized by the design team, the AAAI Program has elected to create an Industry Liaison Section (ILS) to serve as the Program's technology transfer focal point. The process by which the ILS may be established, organized and managed is described, including the baseline organizational structure, duties, functions, authority, responsibilities, relations and policies and procedures relevant to the conduct of the ILS. Author N91-10049*# National Aeronautics and Space Administration. Ames Research Center, Moffett Field, CA. BODY WEIGHT OF HYPERSONIC AIRCRAFT, PART 1 Mark D. Ardema Oct. 1988 62 p (NASA-TM-101028; A-88279-Pt-1; NAS 1.15:101028) Avail: NTIS HC/MF A04 CSCL 01C The load bearing body weight of wing-body and all-body hypersonic aircraft is estimated for a wide variety of structural materials and geometries. Variations of weight with key design and configuration parameters are presented and discussed. Both hot and cool structure approaches are considered in isotropic, organic composite, and metal matrix composite materials; structural shells are sandwich or skin-stringer. Conformal and pillow-tank designs are investigated for the all-body shape. The results identify the most promising hypersonic aircraft body structure design approaches and their weight trends. Geometric definition of vehicle shapes and structural analysis methods are presented in appendices. Author N91-10050# Institut Franco-Allemand de Recherches, Saint-Louis (France). FAST STEERING OF THE ANGLE OF ATTACK: A V. Fleck 20 Jun. 1989 22 p Presented at DEA-1060 Meeting, A method for using fast jet actuators for steering the angle of attack of projectiles is described. In order to minimize the reaction time the response to pulse commands is analyzed. The conditions for inducing an angle of attack along a short flight path are defined. The cases of projectiles rotating slowly and fast, or not rotating at all, are examined. The shortest distance for achieving a flight path correction is the half wavelength of the pitching or yawing frequency of the projectile. To illustrate the ability of the method developed for solving interception problems, a test is carried out. The interception of an airplane maneuvering with 3 g by a guided projectile with a speed of 1800 m/s is analyzed. ESA N91-10051# Federal Aviation Administration, Atlantic City, NJ. The results of three tests performed on a window and window frame of a Boeing 707 are presented. The purpose of the test, conducted at the Federal Aviation Administration Technical Center, was to determine the maximum moment the window could withstand before becoming dislodged from its frame due to the failure of the window retention clips. The window assembly was modified to fit into a load machine. The loads were measured with a load cell and recorded on a Honeywell Test Management System. Author Two concepts for improved aircraft in-flight smoke evacuation were analyzed and tested. The concept definition and evaluation efforts involved an additional ventilation outflow valve on the aircraft underside along with either increased ventilation air volume from the engine compressors or a supplemental ram air supply. Subsequent test aircraft modification involved addition of a pressure controlling outflow valve on the top of the fuselage and upgraded engine bleed air volume flow for cabin air-conditioning. Ground and flight tests were conducted on a test B757 with buoyant and nonbuoyant theatrical smokes generated continuously in various places in the passenger cabin. Buoyant smoke could be localized only when generated in the vicinity of the upper lobe outflow valve. Nonbuoyant smoke could be localized only when generated in the vicinity of an outflow valve, whether the valve was on the top or bottom of the fuselage. The buoyant smoke was formulated to have the same type flow behavior as a plume from the visible flames of a burning surface. The nonbuoyant smoke might be more representative of a smoldering material. Author N91-10053# National Aerospace Lab., Tokyo (Japan). A CONSIDERATION ON FLIGHT PATHS FOR Kingo Takasawa and Fumiko Itoh Jan. 1990 30 p In JAPANESE; (NAL-TR-1051; ISSN-0389-4010) Avail: NTIS HC/MF A03 Flight paths for microwave-powered airplanes were investigated under uniform wind conditions. Some techniques for deducing flight paths are discussed. The loci of airspeed vectors which lead to preferable flight paths are sorted into four types. The effects of added higher harmonic components are discussed. For each type of airspeed vector loci, three kinds of solving methods are applied and 12 solutions are obtained. Examples of flight paths are illustrated with their mathematical expressions, and characteristics are discussed. Preferable flight paths from the view point of airplane design are described. Author N91-10054# National Aerospace Lab., Tokyo (Japan). PRACTICAL FLIGHT PATHS FOR MICROWAVE-POWERED AIRPLANES Takeshi Ito Jan. 1990 15 p (NAL-TR-1052T; ISSN-0389-4010) Avail: NTIS HC/MF A03 Although some types of closed flight paths have been proposed for microwave powered airplanes, they have unfavorable features from the viewpoint of airplane designers, especially under strong wind conditions. Here, by working out several methods of defining the airspeed vector, smooth practical periodic flight paths are deduced. Author N91-10055# Messerschmitt-Boelkow-Blohm G.m.b.H., Munich (Germany, F.R.). Helicopter Div. MBB'S BO 108 DESIGN AND DEVELOPMENT Helmut B. Huber and Claus Schick May 1990 15 p Presented at 46th American Helicopter Society Annual Forum and Technology Display, Washington, DC, 21-23 May 1990 (MBB-UD-0568-90-PUB; ETN-90-97838; OTN-027636) Avail: NTIS HC/MF A03 The development by MBB of a new light twin, multipurpose helicopter, designated as the BO-108 is described. The design requirements and the technology advances in terms of the various components involved (rotor systems, drive system, anti-vibration system, control system, airframe, cockpit and cabin) are presented. An overview on the current status of bench and in-flight testing is given and the progress achieved in the fields of performance, flying qualities, noise and vibrations, weight, reliability and safety is assessed. Studies for increasing the aircraft's capabilities are described and a prospective about the future program plans is given. ESA N91-10056# Rolls-Royce Ltd., Bristol (England). PROGRESS IN CERTIFYING F402-RR-408: THE IMPROVED David J. Martin Derby, England 19 Sep. 1989 10 p Presented The operational background of the Harrier/AV8 family of aircraft was used to define a demonstrator program for improved performance. The XG15 demonstrator program was completed in April 1988. The results formed the basis of the improved F402-RR-408 engine. The validation test program commenced with an engine roll out in June 1988 and is due for completion in May 1990. A summary of technical issues and program status is given. 06 AIRCRAFT INSTRUMENTATION ESA Includes cockpit and cabin display devices; and flight instruments. For related information see also 19 Spacecraft Instrumentation and 35 Instrumentation and Photography. N91-10057 National Aerospace Lab., Tokyo (Japan). (NAL-TM-590; ISSN-0452-2982; JTN-90-80017) Avail: NTIS Trial fabrication of a triaxial sensor system, in which alpha is the front angle and beta is the side angles, and performance of wind tunnel tests are presented. An experiment based on the two-dimensional vector volume measurement method using a blast wind tunnel was performed to prove the measurement theory of the triaxial alpha/beta sensor system and to compare the measurement accuracy between the results obtained from a normally functioning sensor and a malfunctioning or out-of-order sensor. Values and errors were calculated from data obtained from three sensors under four different wind velocities of 10, 20, 30, and 40 m/s against a fixed air current of alpha zero beta zero in the wind tunnel. The accuracy of measurement was determined by comparing the measured data with the second and third sensor, first and third sensor, and first and second sensor. The results of the experiment indicated that the measurement of this system was extremely accurate. Even if one of the sensors becomes defective, the accuracy will not reduce the reliability limit as the other sensors functioned normally. Thus the feasibility of this system has been acknowledged. NASDA N91-10058*# National Aeronautics and Space Administration. Langley Research Center, Hampton, VA. NASA TRANSPORT SYSTEMS RESEARCH VEHICLE B-737 DATA LINK SYSTEM AND DISPLAY FORMATS Charles E. Knox and Charles H. Scanlon Aug. 1990 22 p (NASA-TM-102717; NAS 1.15:102717) Avail: NTIS HC/MF A03 CSCL 01C A data link system was designed to support flight tests in the NASA Transport Systems Research Vehicle B-737 airplane. The purpose of the flight tests was to evaluate pilot acceptance of using data link as the primary source of communications for strategic and tactical air traffic control clearances, weather information, and company messages. The airborne functional operations of the data link system flight tested in 1990 are described. Author 07 AIRCRAFT PROPULSION AND POWER Includes prime propulsion systems and systems components, e.g., gas turbine engines and compressors; and onboard auxilliary power plants for aircraft. For related information see also 20 Spacecraft Propulsion and Power, 28 Propellants and Fuels, and 44 Energy Production and Conversion. N91-10059 National Aerospace Lab., Tokyo (Japan). Shigeo Inoue, Hiroshi Usui, Mitsuhiro Minoda, and Hiroyuki Nose Effects of coolant injection on turbine aerodynamic characteristics were investigated with a test turbine. The main air flow was unheated and the temperature was about 100 C. The coolant (secondary air) temperature was kept at about 100 C, nearly the same as that of the main flow. The present investigation is concerned with effects of coolant injected from the following parts on turbine aerodynamic characteristics: (1) stator blades, (2) both stator and rotor blades, (3) stator casing, and (4) rotor casing (shroud ring). The test facility, the test turbine, and the measuring systems are described. NASDA N91-10060 National Aerospace Lab., Tokyo (Japan). Using a test turbine, the effect of coolant injection was investigated on turbine aerodynamic characteristics. The effects of the coolant injection from a rotor casing with 30 deg slanted holes are described. The discussed turbine efficiency introduced is based on torque, rotational speed, mass flow rate, and the radial and tangential distributions of total pressure and flow angles. It may be concluded that there are some reductions in total pressure losses and increases in outlet flow angles in the tip region caused by the coolant injection. NASDA N91-10061*# Ohio State Univ., Columbus. Dept. of Aeronautical and Astronautical Engineering. SUPERSONIC COMBUSTION ENGINE TESTBED, HEAT D. Hoying, C. Kelble, A. Langenbahn, M. Stahl, M. Tincher, M. (NASA-CR-187010; NAS 1.26:187010) Avail: NTIS HC/MF A06 CSCL 21E The design of a supersonic combustion engine testbed (SCET) aircraft is presented. The hypersonic waverider will utilize both supersonic combustion ramjet (SCRAMjet) and turbofan-ramjet engines. The waverider concept, system integration, electrical power, weight analysis, cockpit, landing skids, and configuration modeling are addressed in the configuration considerations. The subsonic, supersonic and hypersonic aerodynamics are presented along with the aerodynamic stability and landing analysis of the aircraft. The propulsion design considerations include: engine selection, turbofan ramjet inlets, SCRAMjet inlets and the SCRAMjet diffuser. The cooling requirements and system are covered along with the topics of materials and the hydrogen fuel tanks and insulation system. A cost analysis is presented and the appendices include: information about the subsonic wind tunnel N91-10062 Rensselaer Polytechnic Inst., Troy, NY. Jacques Constant Richard 1989 140 P Avail: Univ. Microfilms Order No. DA9018446 An advanced beam-powered propulsion system, called an External Radiation-Heated (ERH) thruster is studied. The repetitively-pulsed, airbreathing engine develops thrust by expanding high pressure, radiation-heated gas over an annular shroud surface. The blast waves are generated by laser radiation heating of air using Laser Supported Detonation (LSD) waves. The phenomenology of LSD waves is described, as is the blast waves and resultant impulse they produce. Analytical simulation of the ERH thruster is accomplished with a one-dimensional model of blast waves propagating uniformly and radially outward from a laser-generated line source of high pressure, high temperature gas. Cylindrical blast wave scaling relationships developed by Sedov are employed in this model. The possibility of including other physical phenomena in the analysis are reviewed. The analyses for the ERH thruster model are performed for a sample vehicle point design. This vehicle, known as the Lightcraft Technology Demonstrator (LTD), may be constructed within the next five years to illustrate the potential of Earth-to-Orbit laser propulsion. The external flow over the LTD vehicle was analyzed to determine basic drag characteristics, inlet total pressure recovery and capture air mass flow rate. Dissert. Abstr. 7 p N91-10063# Rolls-Royce Ltd., Derby (England). (PNR-90634; ETN-90-97142) Avail: NTIS HC/MF A02 Sensitivity of power plant mass to such variables as vehicle thrust requirements, precompression surface incidence, intake and nozzle designs and turbo machinery design constraints is described for an example of turboramjet power plant propelling the first stage of a two stage to orbit launcher. The propulsion system consisted of a turbojet engine behind a rectangular ramp intake with the reheat system operating as a ramjet burner for flight beyond approximately Mach 3. The core engine was isolated from the airflow at these conditions. Several of the aspects of overall vehicle performance are described where these interact with the power plant design, and the influence of mission definition on power plant optimization is discussed. ESA (Contract NAS3-23051) (NASA-CR-182123; E-4137; NAS 1.26:182123) Avail: NTIS HC/MF A03 CSCL 21E Unsteady blade surface pressure data for the Large-Scale Advanced Prop-Fan (LAP) blade operation with angular inflow, wake inflow and uniform flow over a range of inflow Mach numbers of 0.02 to 0.70 is provided. The data are presented as Fourier coefficients for the first 35 harmonics of shaft rotational frequency. Also presented is a brief discussion of the unsteady blade response observed at takeoff and cruise conditions with angular and wake inflow. Author N91-10066# Rolls-Royce Ltd., Derby (England). AERO ENGINE DESIGN FACTORS FOR A LOW FUEL PRICE SCENARIO S. J. Hartropp 15 May 1989 20 p Presented at Canadian Aeronautics and Space Institute, Ottawa, Ontario, 15-17 May 1989 (PNR-90681; ETN-90-97928) Copyright Avail: NTIS HC/MF A03 The driving parameters for aero engine design were reassessed to account for the stabilization of fuel price in the vicinity of 50 cents per gallon. A program embracing studies in the fields of operating cost analysis, reliability research and engine specific thrust effects established principles reflecting the importance of engine direct operating cost. The same factors influence the aircraft life cycle cost, and as legislative compliance, operator acceptance and passenger appeal. The effect of applying these principles to a new powerplant and the ongoing development of current powerplants is evaluated. ESA N91-10067# Rolls-Royce Ltd., Derby (England). M. H. Coney 28 Sep. 1989 25 p Discussion held in Leatherhead, Thermal fatigue cycling in turbine blades under laboratory conditions is used to complement engine development testing and component theoretical lifting methods. The technique produced the required component temperatures by flame heating with a kerosene burning Dart engine combustor. The equipment improvements provide direct and gas bending load simulation and a high level of accuracy in cycle generation and control. Failure results show good agreement with those observed during engine service. ESA N91-10068# Rolls-Royce Ltd., Derby (England). G. M. Lewis 27 Oct. 1989 14 p Presented at DGLR Symposium on 50 Years of Jet-Powered Flight, Munich, Fed. Republic of Germany, 26-27 Oct. 1989 (PNR-90707; ETN-90-97939) Copyright Avail: NTIS HC/MF A03 The by-pass principle was understood in the early days of the jet engine. Exploitation of the known concepts progressed as the inherent design problems were solved. The advances which reduced the mechanical design problems of aircraft engines and components are summarized. Engine designs representing significant steps in the evolution of the by-pass engine are identified. ESA N91-10069# Rolls-Royce Ltd., Coventry (England). Industrial and Marine. GAS TURBINES FOR MAIN PROPULSION AND AUXILIARY D. J. Pratley and D. A. Owen Derby, England 13 Jul. 1989 (PNR-90709; ETN-90-97940) Copyright Avail: NTIS HC/MF A03 The warship machinery requirements concerning reliability, flexibility, maintenance time, service life, noise level, exhaust and infrared emission are discussed. The aero derivative gas turbines and the reasons for selecting gas turbines for marine propulsion are given. The characteristics of operation of several turbines and their installation in ships are described. Suggestions for turbine power increase are given. ESA N91-10070# Rolls-Royce Ltd., Bristol (England). TECHNOLOGY UPDATE OF EARLY GAS TURBINE DESIGNS Alan Rhodes Derby, England 21 Sep. 1989 12 p Presented at Tactical V/STOL Aircraft Symposium, New Bern, NC, 19-21 Sep. 1989 (PNR-90710; ETN-90-97941) Copyright Avail: NTIS HC/MF A03 The power plant of the Pegasus gas turbine is described. The service hours of Pegasus from 1969 to 1989 in different countries are presented. The design evolution of several modules and subassemblies are shown. The improvements obtained by the total package of changes introduced through the Pegasus update program are summarized. The application of up to date technology to the system provides a cost effective way of bringing to the operator a competitive product. N91-10071# Rolls-Royce Ltd., Bristol (England). FUTURE SUPERSONIC TRANSPORT POPULSION OPTIMIZATION ESA Presented B. W. Lowrie Derby, England 8 Nov. 1989 8 p ar European Symposium on Future Supersonic/Hypersonic Transport, Strasbourg, France, 8-9 Nov. 1989 (PNR-90737; ETN-90-97950) Copyright Avail: NTIS HC/MF A02 The interest in second generation supersonic transport is considered. The propulsion systems necessary for a commercially and environmentally acceptable aircraft are identified. It is shown that for an isolated installation the tandem fan concept is the best. A feature of most other systems is the increased installation cross section required at a cruise and this causes penalizing levels of ware drag of an isolated system. Typical weight penalities are found to be of less importance than the wave drag. The need to consider integrated rather than isolated installations is emphasized. ESA N91-10073# Rolls-Royce Ltd., Coventry (England). Advanced Technology Center. FABRICATION ASPECTS OF GLASS MATRIX COMPOSITES FOR GAS TURBINE APPLICATIONS David A. Clarke Derby, England 12 Apr. 1990 12 p Presented at Warwick University Institute of Physics Conference on New Materials and Their Applications, Coventry, England, 10-12 Apr. 1990 (PNR-90752; ETN-90-97956) Copyright Avail: NTIS HC/MF A03 The background to the development of Glass Matrix Composites (GMC's) including the basic fabrication methods is presented. Some of the key problems involved in manufacturing production quantities of GMC gas turbine components are described. The need for highly repeatable, and hence largely automated, processing methods are highlighted. Glass/glass-ceramic matrix composites have mechanical properties suitable for use in gas turbines. The requirement for reliable production process is the repeatability to ensure high quality and the minimum post-fabrication inspection. ESA N91-10074# Rolls-Royce Ltd., Derby (England). HEAT TRANSFER IN AERO ENGINE GAS TURBINES, PART 1 C. T. J. Scrivener 15 Jun. 1990 37 P Submitted for publication (PNR-90754-Pt-1; ETN-90-97958) Copyright Avail: NTIS HC/MF A03 Some turbine blade designs, and some important aspects of airfoil internal heat transfer are described. The airfoil external heat transfer is discussed. For the rotor blades of high temperature gas turbines, modern multipass cooling configurations provide efficient effective cooling. They can provide low coolant flow, consistent with this high temperature capability. The heat transfer in airfoil internal passages is well understood. This includes both plain passages, and the characteristics of bends, and enhancement by ribs, pedestals and impingement. The areas where future heat transfer research is required, in order to understand the basic process involved, are summarized. ESA N91-10075# Rolls-Royce Ltd., Derby (England). RE-ENGINING: REAL STAGE 3 COMPLIANCE PLUS OTHER K. Goddard 6 Apr. 1990 7 p Presented at Avmark Services A study to show that re-engining is the only satisfactory way in converting today's noisy stage 2 airliners to give stage 3 compliance with clear and comfortable margins, together with enhanced performance and improved fuel consumption is presented. The importance of eliminating stage 2 operations for the benefit of the community is summarized. The advantages and driving force behind previous post war re-engining programs are described. ESA N91-10076# Rolls-Royce, Inc., Atlanta, GA. FANS R. R. Moritz and D. J. Nicholas (Rolls-Royce Ltd., Derby, England) Derby, England 15 May 1990 16 p Presented at 37th Annual General Meeting and 2nd Symposium on Propulsion, Toronto, Ontario, 15 May 1990 (PNR-90758; ETN-90-97960) Copyright Avail: NTIS HC/MF A03 Some of the lessons learned in the course of the generation of the RB211 series of engines are presented. The early stages of RB211 development are underlined. Recent experience from present day RB211 program staff is stressed. The RB211 family of engine is compared to other high bypass ratio civil engines. The most obvious differences is in its use of lower aspect ratio fan blades. This feature is credited with a wide range of benefits including better performance, durability and cost of ownership. These and other points are developed. ESA |