Aircraft Turbine Engine Cost Model Calculator
This calculator requires the use of Javascript enabled and capable browsers. This ATEC model uses equations for estimating development and production costs and time of arrival for U.S. military turbojet and turbofan engines. This particular model was used as a teaching aid for developers and project leaders within NASA at the Johnson Space Center (JSC). It is neither classified nor is it under any copyright; it is available to the general public by request to NASA. NASA assumes no liability for the use of information or techniques in this program, nor do we. Interest in further investigation of aircraft turbine engine cost estimating relationships (CERs) grew out of the availability of data for engines recently developed, and experience with the CERs in Rand's computer model for estimating Development and Procurement Costs of Aircraft (DAPCA). After establishing criteria for selecting explanatory variables and CERs, regression analysis was applied to the expanded database to develop improved relationships for the cost of development to the model qualification test (MQT), total development cost, and the cumulative average price at the 1000th production engine. The engine characteristics that best explain development cost through MQT and production cost are maximum thrust of the engine at sea-level-static conditions, an indicator of engine size; Mach number, a measure of performance; and turbine inlet temperature, the dominant technical parameter in the engine cycle. For total development cost, which includes the expenses involved in developing a new engine to MQT, plus the cost to correct service related deficiencies and costs for continual performance and reliability improvements over time, the derived equation includes a production quantity term as well as thrust and Mach number. The estimating relationship for time of arrival (TOA) was also refined in this study. The TOA method links certain engine performance characteristics with time to provide a measure of an engine's state of the art. The refined TOA model is based on 29 U.S. military turbojet and turbofan engines developed and produced during the past 30 years. The model predicts the man-rated MQT date as a function of certain of the engine's performance and design parameters. The parameters include engine thrust to weight ratio, turbine inlet temperature, and specific fuel consumption, which are the three most important technical characteristics in the turbine engine development process. These models are intended for use by long range military planners attempting to determine costs for new systems - especially those of a technically advanced nature - so that better estimates can be made. All parameters needed are readily available at an early stage of planning for a new system. Care must be exercised in using these models to ensure that inputs are consistent with the data base used in this study. For example, cost estimates will reflect military technology and the manner in which programs were conducted during the 1950s, 1960s, and 1970s. If an engine is developed that is not in the mainstream trend, such as a variable cycle or lift engine, the estimating relationship described may not apply. To the extent that a new program differs from historical conditions, extrapolation will be necessary. Source: "Development and Production Cost Estimating Relationships for Aircraft Turbine Engines," J. L. Birkler, J. B. Garfinkle, K. E. Marks, Oct. 1982, Rand, N-1882-AF
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Updated 6.02.11
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