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The Congress directed the Secretary of Transportation to establish a Civil Tiltrotor Development Advisory Committee (CTRDAC). This committee examined the costs, technical feasibility, and economic viability of developing civil tiltrotor (CTR) aircraft; the integration of CTR aircraft into the national transportation system; and the resulting national economic benefits. The CTRDAC also determined what further research and development (R&D) and regulatory changes are needed and recommended how CTR aircraft and related infrastructure development costs should be allocated between government and industry. This paper is based on the CTRDAC Report to Congress recommending the creation of a public/private partnership and proceeding with an integrated CTR program. Whether this occurs will be dependent on whether Congress accepts these recommendations and provides funding for the Federal portion of this cost-shared program.

This paper describes a preliminary research flight test program to investigate the development of a gust alleviation system for Commuter and General Aviation Aircraft. The program was conducted on a variable stability Navion aircraft and investigated the use of both up and down flap deflection in combination with elevator to alleviate the effects of gusts. A second phase of the program to investigate methods of sensing gusts in sufficient time for use of this method is currently in the planning stage.

Human factors issues involving the certification of today's transport flight decks are not limited to new aircraft design. To the contrary, most of today's certification activity involves upgrading the flight deck technology of “classic aircraft” or adding new after-market products to current designs. This can include such additions as Flight Management System (FMS) and Global Positioning System (GPS) interfacing to Autopilots and Flight Directors, Multi-Function Control and Display Units (MCDU), Satellite Communications (SatCom) and High Frequency (HF) Data Links, Heads-Up-Display (HUD) technologies, and even complete three-to-two pilot flight deck conversions. All of these changes impact the way in which crews are trained, qualified, and actually operate the aircraft. This paper reviews the background issues involved with minimum crew certification and describes current methods of workload evaluation in transport category aircraft.

A transient air flow simulation model of a typical aircraft vacuum waste system was correlated against limited airplane test results. The model was used to analyze a variety of conditions which could be encountered while in service. The analysis showed that simultaneous flush and a sequential flush of all the lavatories will not have adequate air flow. However, both flight tests and in-service performance to date indicate no problems with inadequate air flow. It is also improbable that simultaneous or sequential flushing will each occur repeatedly in short time intervals. Thus, continuous inadequate airflow will not exist. Therefore, no changes to the system are required.

Innovative Dynamics, Inc. has developed a low cost Icing Flight Testbed aircraft for use in the development, test and certification of ice protection systems. The testbed aircraft is a Piper Malibu (PA46-310P) single engine general aviation aircraft. Over 120 pounds of test equipment and wiring were installed in the Malibu including a modular data acquisition package. The package includes a dedicated data acquisition computer, two video cameras, outside air temperature probe, airspeed, altimeter, Rosemount Ice Detector, Johnson-Williams LWC meter, and a leading edge mounted thermocouple. The package is designed to use off-the-shelf components to easily accommodate a range of ice sensor and de-icing hardware for evaluation and test. A driving force behind the development of the flight testbed was accommodating the needs of a development and certification program with reasonable financial limitations.

The effect of Gurney flaps on three-dimensional wings was investigated in the 7x10 feet low speed wind tunnel. There have been a number of studies on Gurney flaps in recent years. However, these studies have been limited to two-dimensional airfoils. A comprehensive investigation on the effect of Gurney flaps for a wide range of configurations and test conditions was conducted at Wichita State University. In this part of the investigation, straight and tapered three-dimensional wings with Natural Laminar Flow (NLF) airfoil sections were tested. Gurney flaps spanning 4.5, 3.0, and 1.5 feet were tested on a straight NLF wing of 5 feet span. Compared to the clean wing, the 4.5 feet span 0.017c and 0.033c height Gurney flaps increased the maximum lift coefficient by 17% and 22%, respectively. The increase in maximum lift coefficient was proportionately smaller with the shorter span Gurney flaps.

The demand for business aircraft is very sensitive to price changes. An important part of the aircraft design process is the assessment of the market price for the new designs or model derivatives to determine their economic feasibility. This paper presents a method to be included in the aircraft design process which enables engineers to design to price. The method is based on a relationship between the aircraft market price and the value of the aircraft to the customers. The present work focuses on multi-engine turbine aircraft and involves nineteen aircraft attributes that are of value to business aviation customers to determine the aircraft market price.

Boeing is currently fundamentally rethinking and radically simplifying the processes related to airplane configuration definition and production. The presentation will describe reasons for embarking on this effort and a description of the fundamental production control processes Boeing will deploy. Process Engineering will be described using Boeing's program as an example.

An automated, sleeveless method of coldworking used in either a robotic or traversing slide application is discussed. The coldworking end effector, developed by West Coast Industries, uses the split mandrel coldworking process, thus obviating the need for the complex handling of the split sleeve and its associated costs. Sensors mounted on the end effector provide feedback to the robotic controller, and may be used for Statistical Process Control (SPC). The unit may be used to coldwork 2000 and 7000 series aluminum alloys, with hole sizes ranging from 4.4 mm to 12 mm, and 1.5 mm to 50 mm stackup thickness.

Chassis of automotive vehicles are modified for a number of specialist roles for certain typical applications. Modification of standard chassis for such roles result in increase of payload, axle load, and shifting of position of centre of gravity as compared to original vehicle. These changes have effect on performance parameters of vehicle including dynamic stability and handling. The testing of the modified vehicles for parameter of handling and stability was being done so far at VRDE in the classical method i.e. subjective evaluation by opinion of the expert driver. With the dedicated instrumentation procured now evaluation of the handling and stability characteristics of a vehicle modified for the bullet proof vehicle role was carried out objectively, generally following the ISO test procedures. This study clearly revealed the limitation of roll over stability of the modified vehicle, necessitating some design modification to the suspension system and tyre system of the vehicle.

A Software system has been developed which permits fatigue life predictions to be made for automotive spot welds joining two steel sheets, based on finite-element analyses. The method requires the spot welds in a structure to be modelled as stiff bar elements in a relatively coarse mesh, with the bar elements acting as force transducers. The method uses the bar element cross sectional forces and moments to calculate the “structural stresses” in each spot-weld nugget and the adjacent sheets. The system permits the user to play complex loading histories through a finite element model, using either a quasi-static or transient approach to stress history determination. The method provides a convenient way to predict the locations and lives of fatigue sensitive spot welds, and includes graphical tools to assist in interpretation of results.

Chassis dynamometers are required for different types of regulatory tests like emissions, fuel consumption, etc. as well as for different development tests and running-in of vehicles. With the stringent emission regulations, the chassis dynamometers are required to simulate road resistance accurately and consistently to get repeatable results. This paper describes the new concept of chassis dynamometer using two power devices, an eddy current dynamometer for absorption and a DC machine for generation. Both the machines are controlled through a personal computer (PC) with necessary interfaces. It has been possible to simulate the road resistance accurately on different driving cycles. The software developed has all the required modes for operation. The detailed results are presented in the paper.

Strain controlled tests were performed on 35 C8 steel specimens (IS 3930-1979) to determine cyclic stress-strain curve (CSSC) by Companion Specimens Test (CST), Multiple Step Test (MST) and Incremental Step Test (IST) procedures. A good agreement was found between the CSSCs obtained by CST and MST procedures. The CSSCs obtained by IST procedure using Incremental Step Loading Blocks (ISLB) of different maximum strain amplitude indicate that the parameters of CSSC depend on the maximum strain amplitude in the ISLB and resulted in a family of CSSCs. The dependence of CSSC parameters on the maximum strain amplitude in the ISLB are approximated by polynomials. Fatigue lives estimated based on IST results for irregular strain-time histories were found to be comparable with the experimentally evaluated fatigue lives.

An evolving aircraft synthesis simulation environment which offers improvements to existing methods at multiple levels of a design process is described in this paper. As design databases become obsolete due to the introduction of new technologies and classes of vehicles and as sophisticated analysis codes are often too computationally expensive for iterative applications, the design engineer may find a lack of usable information needed for decision making. Within the environment developed in this paper, rapid sensitivity analysis is possible through a unique representation of the relationship between fundamental design variables and system objectives. The combined use of the Design of Experiments and Response Surface techniques provides the ability to form this design relationship among system variables and target values, which is termed design-oriented in nature.

Electromagnetic Compatibility (EMC) has become an increasingly critical attribute for motor vehicles as the content and functionality of vehicle electronics continues to increase. EMC has long been recognized and managed as a critical performance parameter in the design of consumer appliances, and commercial and military electronic equipment. Similar design discipline is being gradually applied in the automotive industry through the development and implementation of systematic design and measurement techniques. Even though typical customers do not consciously include EMC in the purchasing decisions, non-robust EMC designs can have a negative impact on the customers' perception of quality through poor radio/tape performance and/or faulty operation of electronically controlled functions. Some aspects of vehicle's EMC performance may be controlled through Government regulations.

A 4-wheel drive utility vehicle to meet high technical specifications required for different operating conditions in demanding terrain is developed in modern engineering environment. The paper presents efforts made in indigenous development of the vehicle for off- road and military applications. CAD/CAM/CAE, virtual prototyping techniques were extensively used during development. Prototype vehicles have been tested at high altitudes in India and Europe, in Rajasthan desert, on various test tracks and also on the autobahns in Germany.

Computer simulation using finite element analysis techniques was used to predict and improve the performance of vehicle components and structures. In order to determine the actual loading and validate the FE model, extensive physical testing which involved data acquisition and analysis was undertaken. The paper shows the application of FE analysis and testing with examples for optimization of an automotive wheel, drive line vibration, car body shell interior acoustics and a railway vehicle structure.

Over the past three decades the automotive electronics industry has progressed from transistorized voltage regulators in the 1960's to vehicles today with more than 30 electronic modules containing complex integrated circuits such as microprocessors, DSPs and smart analog ICs. These sophisticated ECUs (Electronic Control Units) have been primarily driven by the need to meet Government regulations on emissions and fuel economy and partially by market pressures for differentiation. The result has been a proliferation of independent, self supporting electronic modules with complex wiring interconnects, and, in many cases, redundant features. This “add a function, add a module” approach coupled with traditional design methodologies has created new challenges for the automotive industry in the areas of costs, diagnostics and more recently design cycle time.

Brakes on vehicles are safety items. Their failure could result in fatal accidents. It is therefore necessary that quality control tests are conducted on this vehicle sub system to ensure that individual component parts meet well known specifications for good performance. The sand cast brake drums for in-house developed prototype vehicles were tested for chemical composition using atomic optical emission spectrometer, metallographic structure using a metallurgical microscope, and hardness number using Brinnel hardness tester. They were subjected to X-ray examinations to detect casting defects. Other tests such as dimensional accuracy and balancing are not included in this report. Results of the chemical analysis show that the undissolved carbon in the matrix is responsible for specimen high hardness number. The X-ray show the presence of some foreign material of less density. The graphite distribution conforms with recommended type for brake drums.