查看更多>>摘要：The recent increase in flight delays in the U.S. domestic system is analyzed by estimating an econometric model of average daily delay that incorporates the effects of arrival queuing, convective weather, terminal weather conditions, seasonal effects, and secular effects (trends in delays not accounted for by other variables). From the estimation results it was possible to quantify some sources of higher delays in late 2003 and early 2004 and track changes in delays that are not attributable to major causal factors. Results suggest that when these factors are controlled for, delays decreased steadily from 2000 through early 2003, but that the trend reversed thereafter. Of the total delay increase between early 2003 and early 2004, half to two-thirds can be attributed to specific sources.
查看更多>>摘要：The current demand management policy at LaGuardia Airport (LGA) New York, must be changed in 2007 under the provision of the Wendell H. Ford Aviation Investment and Reform Act for the 21st Century of April 2000 (AIR-21). As a preliminary step for developing a new policy, this study considered how past policies, along with other factors, have affected operational performance at LGA. The interaction between LGA and the rest of the aviation system was also investigated by estimating simultaneous equations of average delay for LGA and the National Airspace System (NAS) by using two-stage least squares. The results demonstrate that the arrival delay impact of AIR-21 on LGA was in the form of Increased Ground Delay Program holding and that although delay increased markedly under AIR-21, there were also observable improvements in the ability of LGA to handle traffic. Furthermore, on the basis of the simultaneous equations analysis, it was found that 1 min of arrival delay at LGA causes about 2 min of delay elsewhere in the NAS, suggesting that demand management at LGA is a national rather than a local issue.
Katherine KeeganScott D. MurrellGuy ZummoGonzalo Rada...
p.105-111页
查看更多>>摘要：Foreign object damage (FOD) is a term used by the aviation industry to describe damage caused by any object that can be ingested by an aircraft engine or flight control mechanism. FOD is estimated to cost the global aerospace industry up to $4 billion annually. Deteriorated pavements are one source of FOD and fall into two categories: runway, taxiway, and apron pavements that aircraft traverse and shoulders and other infield pavements that are not traversed but are subjected to jet blast. Widely recognized procedures for the assessment of pavements traveled on by aircraft are well documented. However, procedures for the assessment of FOD potential for shoulder and blast pavements at commercial airports are not widely recognized. In an effort to manage shoulder and blast pavements proactively and eliminate pavement-related FOD incidents, the Port Authority of New York and New Jersey undertook to assess the current condition of these pavements, rehabilitate and repair areas with unacceptable FOD potential, and initiate periodic inspections on these pavements to facilitate the implementation of an effective pavement maintenance and rehabilitation program. To achieve this goal, a dual project- and network-level inspection approach was implemented. The project-level objective was to identify immediate repairs needed to address unacceptable FOD potential. The network-level objective was to assess the current condition and initiate a proactive inspection regime to assist in maintaining these pavements. The approaches to assessment and rehabilitation are detailed and steps to implement a pavement management system for these pavements are discussed.
查看更多>>摘要：The estimation of advanced air travel itinerary share models formulated to capture interitinerary competition dynamics along the time-of-day dimension is reported. These models predict airline ridership at the itinerary level and aid carriers in long- and intermediate-term decision making. Previous estimations by the authors indicated increased competition among air travel itineraries within broad time periods. In this study, a more realistic time-of-day competition dynamic is modeled with the ordered generalized extreme value (OGEV) model and hybrid OGEV models. The hybrid OGEV models incorporate the traditional OGEV model structure with other GEV components such as the nested logit (NL) and weighted NL model structures. These hybrid OGEV models measure interitinerary competition along the carrier or level-of-service dimensions along with the time-of-day dimension. The estimated OGEV models have the property of proximate covariance in which itineraries that are closer to each other by departure time exhibit greater covariance and therefore greater substitution or competition with each other than with itineraries that are more separated in time. Independent variables for all of the models measure itinerary service characteristics such as level of service, connection quality, carrier attributes, aircraft type, and departure time. Finally, all models estimated in this study offer insights into air traveler behavior, with the advanced models outperforming the more basic specifications with regard to statistical tests and behavioral interpretations.
NETL
NSTL