A Performance Measure for Evaluating Aircraft Landing Trajectories
A general performance index is developed for evaluating aircraft landing trajectories. The primary term in the index is the effect of noise on people residing near the air terminal. Other terms included are passenger comfort, fuel consumed, and the time spent in the near-terminal area. Models are developed for aircraft engine noise, passenger comfort, the population distribution about a specific airport, and the aircraft flight behavior. While this performance index may be used in computing optimal trajectories, it is also useful for comparing nonoptimal trajectories which, for one reason or another, may be worthy of consideration. Some examples of such comparisons are included through simulations of landing. The aircraft considered is a Boeing 737.
Determining STOL Ride Quality Criteria-Passenger Acceptance
The ability to mathematically model human reaction to variables involved in transportation systems offers a very desirable tool both for the prediction of passenger acceptance of proposed systems and for establishing acceptance criteria for the system designer. As a first step in the development of a general model for STOL systems, a mathematical formulation is presented which accepts as inputs nine variables felt to be important in flight under STOL-type conditions and presents an index of human response as the output. The variables used are three linear motions, three angular motions, pressure, temperature, and noise level. The model is based on a deterministic approach, and was calibrated using data obtained by recording quantitative subjective responses of special test subjects while simultaneously measuring all variables. Several aircraft types were used under both experimental flight conditions and commercial airline operations. Ride quality criteria developed by using the model to study response to various combinations of the variables over extended ranges of frequency, amplitude, and rates of change will be presented. The results can be used to establish specifications for stability augmentation systems to improve the ride quality of existing STOL aircraft.
Procedures for estimating the effects of design and operational characteristics of jet aircraft on ground noise
Procedures have been developed for estimating the effects of design and operational characteristics of jet aircraft on ground noise including various engine-cycle parameters, aircraft-design characteristics, and aircraft-flight characteristics. Parametric plots have been prepared to show how these different interrelated factors influence noise; and, when possible, assessments have been made of the accuracies and limitations of the graphs, nomographs, and equations that have been developed. This paper presents a review of these studies.