Ira D. Jacobson

Ride Quality Evaluation 1. Questionnaire Studies of Airline Passenger Comfort

As part of a larger effort to assess passenger comfort in aircraft, two questionnaires were administered: one to ground-based respondents, the other to passengers in flight. Respondents indicated the importance of various factors influencing their satisfaction with a trip, the perceived importance of various physical factors in determining their level of comfort, and the ease of time spent performing activities in flight. The in-flight sample also provided a rating of their level of comfort and of their willingness to fly again. Comfort ratings were examined in relation to (1) typo of respondent, (2) type of aircraft, (3) characteristics of the passengers, (4) ease of performing activities, and (5) willingness to fly again.

Ride Quality Evaluation II: Modelling of Airline Passenger Comfort

Quantitative environmental and subjective data obtained aboard commercial airlines are used to model passenger reaction. Several models for comfort are compared. The manner in which the overall response to the flight environment depends on the time history is examined and the variability about the mean response discussed. The relationship to passenger satisfaction is presented giving a quantitative means of relating the physical environment to passenger acceptance. The proposed models give aircraft designers and operators a method by which they may seek to maximize passenger comfort and therefore satisfaction.

Ride Quality Assessment III: Questionnaire Results of a Second Flight Programme

Abstract Aquestion was completed by 861 passengers on regularly-scheduled flights of four commuter airlines. Four types of aircraft were involved. Questions assessed major demographic variables, attitudes toward flying, frequency of flying, experience of airsickness, and passenger perceptions of detailed aspects of the physical environment. Passengers also rated their overall comfort level and their willingness to fly again. Passengers perceivo motion, noise, and seat factors as the primary determinants of their comfort. Rated comfort is strongly related to willingness to fly again. Incidence of airsickness was low. Sox differences in reactions to aspectsof the environment were found.

A nonlinear oscillator analog of rigid body dynamics

A rigorously valid nonlinear oscillator analog of the torque-free rotational dynamics of a general rigid body is presented. The analog consists of threeuncoupled nonlinear oscillators, the motion of each being governed by a second order nonlinear ordinary differential equation of the Duffing type. The nonlinear oscillator analog and three associated phase planes, as established herein, provide a new basis for analysis and visualization of rigid body dynamics. The phase planes are particularly useful in providing complete visibility of the motions limiting cases and stability properties.

The comfort and satisfaction of air travelers - Basis for a descriptive model

The results of a questionnaire and interview survey are used as a basis for proposing a descriptive model of the comfort and satisfaction of the commercial air traveler. Passenger attitudes toward the present commercial air travel system are examined. Comfort is interpreted as being represented by a four-dimensional composite of commonly encountered environmental variables. Satisfaction is represented as a composite of safety, cost-benefit, luxury, and in-flight activity dimensions.

Ride Quality Evaluation IV: Models of Subjective Reaction to Aircraft Motion

Time motion histories and judgments of perceived comfort were obtained for three planes (Nord, Twin Otter, Beech) and a helicopter (S-61). Regression models were obtained predicting rated comfort from rms values for six degrees of freedom of motion. The model C  =  2.1 + 17.1 T + 17.2 V gives a good fit to the plane data, but is less acceptable for the helicopter data.

The impact of interior cabin noise on passenger acceptance

Based on flight test data gathered in general aviation aircraft, a composite motion-noise passenger comfort model has been developed which enables the assessment of cabin interior noise impact on passenger acceptance. Relationships between special subject responses and passenger responses are given, as well as the effect of comfort on passenger acceptance. The importance of comfort and noise on the overall passenger reaction is discussed.

Methodology for Multiaircraft Minimum Noise Impact Landing Trajectories

The problem of optimizing landing trajectories with respect to noise impact index is addressed. In contrast with previous work, multilandings are considered. In order to make the problem tractable the trajectories are specified in functional form with certain parameters left free for selection by the optimization methods. Constraint of aircraft dynamic behavior, trajectory separation, pilot workload, passenger comfort, and maximum noise intensity all enter into the determination of what is an allowable trajectory. A version of the quasi-Newton iterative procedure is used to determine the optimum parameter values. The results show improvement in noise impact to the airport considered and the potential for even greater improvement at many airports.

COMFORT REACTIONS TO BUS MOTION ON CURVED ROADWAYS

Physical measurements of the motion of buses on curved roadways were taken in all six degrees of freedom, and comfort responses were obtained from groups of passengers. A model, developed to predict mean comfort responses from motion variables, included both mean and RMS transverse acceleration.

On the Roles of Perceived Safety and Security in Transportation Choice

To what extent does perceived safety and security influence the amount and pattern of use on public transportation systems? While it is assumed to be a major factor in modal choice, there is little empirical research to show that it is. The major relevant studies are briefly reviewed. Then the results of recent surveys of both users and non-users of public transportation are presented. Perceived safety is discussed in relation to frequency of system use, sex, age, and sources of information about transit crime. The influence of other factors on mode choice are also reported.