V. A. Lee

Bio: V. A. Lee is an academic researcher from General Dynamics. The author has contributed to research in topics: Propulsion. The author has an hindex of 1, co-authored 1 publications receiving 30 citations.

Computerized aircraft synthesis.

Abstract: A concept and philosophy of computerized aircraft synthesis is discussed, and Computer Program SYNAC (SYNthesis of AirCraft) is examined in some detail by considering examples of both its construction and its application. An aircraft synthesis computer program involves three principal functions: determination of force characteristics, determination of aircraft performance, and configuration control. There are three groups of variables: independent configuration size and shape variables; intermediate weight-, propulsion-, and aerodynamic-force characteristics variables; and dependent performance variables. Program SYNAC is organized in seven major modules: input, configuration control, geometry, weight, propulsion, aerodynamics, and performance. The program yields accuracies comparable with conventional aircraft synthesis techniques. Computer time per problem is currently on the order of 1 min, and ultimate times of y - of a minute are expected. A typical application of Program SYNAC involves the maximum-range optimization (in terms of wing area, wing thickness ratio, wing aspect ratio, wing taper ratio, and engine size) of a variable wing-sweep configuration for an air-to-ground mission.

Automated procedures for sizing aerospace vehicle structures /SAVES/

Abstract: Results from a continuing effort to develop automated methods for structural design are described. A system of computer programs presently under development called SAVES is intended to automate the preliminary structural design of a complete aerospace vehicle. Each step in the automated design process of the SAVES system of programs is discussed, with emphasis placed on use of automated routines for generation of finite-element models. The versatility of these routines is demonstrated by structural models generated for a space shuttle orbiter, an advanced technology transport,n hydrogen fueled Mach 3 transport. Illustrative numerical results are presented for the Mach 3 transport wing.

Computerized Preliminary Design at the Early Stages of Vehicle Definition

Abstract: Criteria for acceptance of early design information, modern methods of providing it, and suggestions for defining adequate levels of resources to accomplish the objectives of the activity are described. Specific examples of the most difficult type of early design studies, those requiring significant undeveloped technology, are used to discuss these points. The examples include design studies and cost estimates of liquid hydrogen fueled aircraft, oblique winged aircraft and remotely piloted vehicles.