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The use of interactive computer graphics for aircraft structural design is discussed. The software used is the Lockheed-California Company Computer-graphics Augmented Design and Manufacturing (CADAM)® system in conjunction with our inhouse Surface Design and Finite Element Model programs. Starting with the conceptual design on the CADAM system, configuration geometry is generated for use by analysis users, preliminary design, loft, and production design organizations. An example used to demonstrate the application of the system is the development of a smaller horizontal tail for L-1011 derivatives, under the sponsorship of the NASA Energy Efficient Transport Technology office. The increased productivity achieved by using the CADAM system is described.

Second generation, or toughened, epoxy resin systems are under consideration for use on a large composite primary structural part such as a wing. A method of evaluating the properties of these materials, while at the same time considering design, structural and manufacturing requirements has been developed. Processability requirements for toughened epoxy resin systems have been established. Cost efficient manufacturing methods, such as pultrusion, have been investigated and found to be a feasible production method for composite structure. The use of pultrusion as a fabrication method for partially staged parts to be co-cured at a later date is being evaluated.

A successful short-haul transport must satisfy customer and marketplace requirements and be attractive economically. This paper examines the marketplace in the late 1970 time period to determine the payload-range and other performance requirements for a wide-bodied twin-jet transport. Environmental and operating cost targets are established, and the size of the market is estimated. An “optimal” design is then described which essentially represents the best possible airplane using the technology available in the time period best suited to the customer and marketplace requirements. Design data are presented that show the sensitivities of the design to some of the primary configuration variables. Certain design compromises are considered that have to do with airframe commonality with the manufacturer's other transports.

The maintenance diagnostics problem is becoming more difficult as weapon systems, operational environments, and tactical requirements become more complex. Existing fighter aircraft have achieved greater than 95% built-in test (BIT) capability, but are experiencing high false removal rates due to fault detection/fault isolation (FD/FI> ambiguities. This paper will shows how to reduce the program risk by implementing testability features as front end requirements. Integrated Diagnostics activities are part of the design process to build testability and supportability into the weapon systems. By influencing the hardware/software design early in the program, a large payoff in logistics costs will result in the operational and support phase.

A new, completely independent monitor (capable of operation through Category IIIc weather condition) for use with automatic landing systems, is undergoing development by Lockheed for possible use in L-1011 aircraft. Following intensive analysis, a Ka band airborne radar was selected to provide pilot confidence through independent monitoring of the L-1011 (1) dual-dual, fail operative, automatic landing system's performance. Lockheed's airborne flying test bed (CV-240) program has so far provided evidence that the Independent Landing Monitor concept has a definite future in commercial automatic landing applications under reduced visibilities. Visual enhancement would improve the acceptability of near zero-zero operation and consequently reduce the number of unnecessary go-arounds.

The paper deals with the emerging and topical subject of All-Electric Aircraft in which the electric system in an advanced airplane serves all the functions and services normally supplied by multiple power systems, such as engine bleed air, hydraulics, pneumatics, and conventional type electric power systems. Engine starting is of particular interest because of its demands for special logistic and maintenance ground support. Military and commercial aircraft typically use pneumatic, cartridge, fuel/air (combustion) or monopropellant starting methods, so these must be replaced by electric starting. The trend of the advanced technology engines is towards high bypass and high compression ratios, making them increasingly sensitive to tapping the compressor airflow: The energy-efficient engine is, therefore, an important design consideration in the All-Electric Airplane.

Area Navigation Systems (RNAV), coupled with appropriate air traffic control techniques, promise to improve the movement of aircraft within the National Airspace System (NAS). These systems are based upon use of the NAS ground radio navigation aids by the airborne navigation receivers, and other sensors available in today's aircraft. The evolution and product development of airborne equipment for this purpose have been guided by airline and FAA operational needs. The airline industry, through its Air Transport Association (ATA) and Airline Electronic Engineering Committees (AEEC), is standardizing the requirements for three classes of equipment. These are: Mark I RNAV, simple, yet requiring considerable pilot manual operation; Mark II RNAV, virtually automatic, with new cathode-ray tube multi-function/navigation displays for the pilot; and Mark III (Mark 13) RNAV, based upon use of the self-contained inertial navigation systems presently installed in today's large jets.

The high equipment investment cost of today's large transport aircraft, the high daily utilization desired or required for profitable operations, and the potential revenue losses associated with service interruptions make it mandatory for the manufacturer to take an active part in the early reduction and correction of service problems. The high investment, not only by the aircraft operators but also by the manufacturer, demands the establishment of a mutual participation team effort for early problem resolution. This paper deals with an aircraft manufacturer's approach to meeting this challenge. It discusses the accumulation and evaluation of service data, the investigations initiated to properly understand the problem, and the management procedures established to assure a safe and speedy problem resolution with a minimum of service interruption. Specific examples are used to illustrate the types of decisions reached.

This paper presents an overview of design considerations, design development, and maintenance practices required to certify a commercial transport aircraft and ensure continuing airworthiness in operation. Subjects discussed include philosophy and criteria of airworthiness with examples of their application; evolutionary nature of the design development; scope of development testing; and the process involving manufacturer, operator, and regulatory agency to ensure continuing airworthiness throughout the aircraft operational life. Also discussed are the recent revisions in airworthiness regulations, which, along with advances in technology, have resulted in changing trends in the approach to substantiating continuing airworthiness, particularly for structures.

Lockheed is currently involved in research and development efforts aimed at applying new concepts to the flight station. TriStar One, Lockheed's flight test L-101 l, is flying a trial installation of color electronic displays on a portion of its instrument panel. Modifications made to the L-1011 Flight Management System control the arrival of the aircraft at its destination to an exact time. This presentation will describe the evolutionary process that has led to the development of airborne digital systems and the integration of new emerging technologies such as color electronic displays into the cockpit. Development of these and other concepts will provide payoffs in the areas of flight safety, fuel conservation, and improved terminal area operations.