Increasing air traffic in the U.S.A has led to runway capacity limitations at the airports. Increasing the capacity of the existing runways involves reducing the runway occupancy time of an aircraft landing on a runway. The location of runway exits plays an important role in minimizing the runway occupancy time. Locating an optimal location for an exit is getting complex with a rapid increase in the number of aircraft types. So, the Air Transportation and Systems Laboratory at Virginia Tech developed the Runway Exit Interactive Design Model (abbreviated as REDIM). This model finds the optimal exit location considering multiple aircraft and a variety of environmental conditions. To find the optimal exit location, REDIM simulates the landing aircraft behavior. The kinematic model simulating the aircraft landing behavior in REDIM using pseudo-nonlinear deceleration heuristic algorithm. REDIM models the aircraft landing behavior into five phases. The five phases are: 1) a flare phase, 2) a free roll period occurring between the aircraft touchdown and the brakes initiation 3) the braking phase, 4) a second free roll phase starting after the braking phase and ending before the turnoff maneuver and 5) a turnoff maneuver phase. The major contributors to the runway occupancy time (ROT) are the braking phase (60% of ROT) and the turnoff phase (25% of ROT). Calculating the turnoff time requires few input variables such as deceleration rate along the turnoff and the speed at which an aircraft takes an exit (exit speed at the point of curvature). The deceleration rate along the turnoff is specific to every aircraft. This study involves predicting the exit speed at the point of curvature based on the type of exit taken. It begins with collecting the exit geometry parameters of 37 airports in the U.S.A. The exit geometry parameters define the type of exit. The ASDE-X data provides the observed exit speeds at the point of curvature for these exits. This study examines a few models with observed exit speeds as the response variable and exit geometry as the predictor variables. / MS / Increasing air traffic in the U.S.A has led to runway capacity limitations at the airports. Increasing the capacity of the existing runways involves reducing the runway occupancy time of an aircraft landing on a runway. The location of runway exits plays an important role in minimizing the runway occupancy time. Locating an optimal location for an exit is getting complex with a rapid increase in the number of aircraft types. So, the Air Transportation and Systems Laboratory at Virginia Tech developed the Runway Exit Interactive Design Model (abbreviated as REDIM). This model finds the optimal exit location considering multiple aircraft and a variety of environmental conditions. To find the optimal exit location, REDIM simulates the landing aircraft behavior. The kinematic model simulating the aircraft landing behavior in REDIM using pseudo-nonlinear deceleration heuristic algorithm. REDIM models the aircraft landing behavior into five phases. The five phases are: 1) a flare phase, 2) a free roll period occurring between the aircraft touchdown and the brakes initiation 3) the braking phase, 4) a second free roll phase starting after the braking phase and ending before the turnoff maneuver and 5) a turnoff maneuver phase. The major contributors to the runway occupancy time (ROT) are the braking phase (60% of ROT) and the turnoff phase (25% of ROT). Calculating the turnoff time requires few input variables such as deceleration rate along the turnoff and the speed at which an aircraft takes an exit (exit speed at the point of curvature). The deceleration rate along the turnoff is specific to every aircraft. This study involves predicting the exit speed at the point of curvature based on the type of exit taken. It begins with collecting the exit geometry parameters of 37 airports in the U.S.A. The exit geometry parameters define the type of exit. The ASDE-X data provides the observed exit speeds at the point of v curvature for these exits. This study examines a few models with observed exit speeds as the response variable and exit geometry as the predictor variables.

This thesis estimates potential runway throughput gains using a reduced wake separation based on the 123 most prevalent aircraft in the United States fleet. The analysis considers Runway Occupancy Time (ROT) constraint factors and existing geometric design factors. This research extracts the historic data from Airport Surface Detection Equipment Model X (ASDE-X) for analysis. The Runway Exit Design Interactive Model (REDIM) is used to optimize the runway exit locations and reduce ROT. The runway throughput and safety factors are generated from a Monte Carlo runway simulator. This thesis focuses on selected US airport runways that could benefit from geometric optimization. The study aims to estimate ROT improvements through improved runway exit locations and the changes in runway throughput considering ROT constraint factors. The results of the thesis show that Dallas Fort Worth International Airport (DFW) runway 35C and Denver International Airport (DEN) runway 16R have the potential to improve the ROT. After the optimization to locate runway exits, the ROT time of the RECAT group F and G aircraft (greater than 90% of the arrivals) was reduced by three to five seconds (a very significant effect). After the ROT reductions and with the application of reduced wake separation criteria with the ROT constraint factor applied, the arrival-only capacity of DFW runway 35C improved by 3.5 arrivals per hour. The arrival-only capacity on DEN runway 16R improved by 2.14 arrivals per hour. Both runways maintained a probability of violation between time-based separation and ROT time at around 1.5%. The study concludes that the application of reduced wake separation criteria alone is a necessary but insufficient condition to improve the efficiency of arrival runways. Through careful improvements of runway exit locations, reductions in ROT provide reliability and efficiency to the operation of runways. / Master of Science / This thesis estimates potential runway throughput gains using a reduced wake separation based on the 123 most prevalent aircraft in the United States fleet. The analysis considers Runway Occupancy Time (ROT) constraint factors and existing geometric design factors. This research extracts the historic data from Airport Surface Detection Equipment Model X (ASDE-X) for analysis. The Runway Exit Design Interactive Model (REDIM) is used to optimize the runway exit locations and reduce ROT. The runway throughput and safety factors are generated from a Monte Carlo runway simulator. This thesis focuses on selected US airport runways that could benefit from geometric optimization. The study aims to estimate ROT improvements through improved runway exit locations and the changes in runway throughput considering ROT constraint factors. The results of the thesis show that Dallas Fort Worth International Airport (DFW) runway 35C and Denver International Airport (DEN) runway 16R have the potential to improve the ROT. After the optimization to locate runway exits, the ROT time of the RECAT group F and G aircraft (greater than 90% of the arrivals) was reduced by three to five seconds (a very significant effect). After the ROT reductions and with the application of reduced wake separation criteria with the ROT constraint factor applied, the arrival-only capacity of DFW runway 35C improved by 3.5 arrivals per hour. The arrival-only capacity on DEN runway 16R improved by 2.14 arrivals per hour. Both runways maintained a probability of violation between time-based separation and ROT time at around 1.5%. The study concludes that the application of reduced wake separation criteria alone is a necessary but insufficient condition to improve the efficiency of arrival runways. Through careful improvements of runway exit locations, reductions in ROT provide reliability and efficiency to the operation of runways.

Uma parcela significativa dos acidentes de trânsito nas rodovias ocorre devido à saída de veículos da pista, o que pode resultar em choques com obstáculos fixos, quedas em espaços vazios, tombamento, capotagem, etc. Esse tipo de acidente é, em geral, grave, em razão das altas velocidades desenvolvidas nas rodovias. Cerca de 1/3 dos acidentes rodoviários com vítimas fatais nos Estados Unidos resultam de saída de pista. No Brasil, estima-se que 30% dos acidentes rodoviários estão relacionados com saída da pista, sendo esse valor da ordem de 25% nos casos dos acidentes com vítimas fatais. Neste trabalho é apresentado o Modelo QRSP (formado pelas letras iniciais das palavras: Quantificação - Risco - Saída - Pista) em rodovias. O modelo permite quantificar o nível de proteção existente em cada segmento particular da rodovia (análise microscópica) e, a partir dessa informação, quantificar o nível de proteção considerando trechos longos (análise macroscópica). No modelo desenvolvido, a avaliação é feita considerando separadamente os dois lados da pista (direito e esquerdo), podendo os resultados serem compostos no caso da quantificação de trechos longos. O modelo foi desenvolvido para o caso de rodovias de múltiplas faixas por sentido (denominadas comumente de pista dupla), podendo, no entanto, também ser empregado no caso das rodovias de duas faixas e duplo sentido (rodovias de pista simples). O modelo QRSP permite determinar parâmetros não fornecidos pelos métodos ABNT (2007) - norma brasileira - e AASHTO (2002) - norma americana, proporcionando, dessa forma, uma melhor quantificação do risco na saída de veículos da pista. A análise dos resultados fornecidos pelo modelo QRSP mostra que o mesmo representa a realidade de maneira satisfatória. As informações quantitativas fornecidas pelo modelo são de grande utilidade na elaboração de projetos de melhoria das características das laterais de rodovias existentes, bem como na preparação de projetos de novas rodovias. / A significant portion of road traffic accidents on highways occurs because of the exit of vehicles from the runway, which may result in collisions with fixed obstacles, falls in empty spaces, overturning, roll over, etc. This kind of accident is in general quite severe, due to the high speeds on highways. Approximately one third of road accidents with fatalities in the United States result from the runway exit. In Brazil, it is estimated that 30% of road accidents are also related to the runway exit, bringing this value at 25% in the cases of accidents with fatal victims. The QRRE that stands for Quantification the Risk in the Runway Exit of vehicles on highways is presented in this research. The model allows to quantify the level of protection in each particular segment of the highway (microscopic analysis) and from this information, it permits to quantify the level of protection considering long segments (macroscopic analysis). In the developed model, the assessment is done considering separately the left and right sides of the runway, and the results can be compounded in the case of long segments quantification. The model was developed for the case of multilanes highways in each direction, however, this model can also be used in the case of two lanes highways with two-ways direction. The QRRE model allows to determine parameters that are not provided by the methods ABNT (2007) - Brazilian standard, - and AASHTO (2002) - American standard, which provides a better measurement of risk in the exit of vehicles from the runway. The results obtained by QRRE model show that it clearly represents the reality. The quantitative information provided by the model are useful for the development of projects in order to improve the characteristics of the roadside highways available, and the development of projects for new highways.

Uma parcela significativa dos acidentes de trânsito nas rodovias ocorre devido à saída de veículos da pista, o que pode resultar em choques com obstáculos fixos, quedas em espaços vazios, tombamento, capotagem, etc. Esse tipo de acidente é, em geral, grave, em razão das altas velocidades desenvolvidas nas rodovias. Cerca de 1/3 dos acidentes rodoviários com vítimas fatais nos Estados Unidos resultam de saída de pista. No Brasil, estima-se que 30% dos acidentes rodoviários estão relacionados com saída da pista, sendo esse valor da ordem de 25% nos casos dos acidentes com vítimas fatais. Neste trabalho é apresentado o Modelo QRSP (formado pelas letras iniciais das palavras: Quantificação - Risco - Saída - Pista) em rodovias. O modelo permite quantificar o nível de proteção existente em cada segmento particular da rodovia (análise microscópica) e, a partir dessa informação, quantificar o nível de proteção considerando trechos longos (análise macroscópica). No modelo desenvolvido, a avaliação é feita considerando separadamente os dois lados da pista (direito e esquerdo), podendo os resultados serem compostos no caso da quantificação de trechos longos. O modelo foi desenvolvido para o caso de rodovias de múltiplas faixas por sentido (denominadas comumente de pista dupla), podendo, no entanto, também ser empregado no caso das rodovias de duas faixas e duplo sentido (rodovias de pista simples). O modelo QRSP permite determinar parâmetros não fornecidos pelos métodos ABNT (2007) - norma brasileira - e AASHTO (2002) - norma americana, proporcionando, dessa forma, uma melhor quantificação do risco na saída de veículos da pista. A análise dos resultados fornecidos pelo modelo QRSP mostra que o mesmo representa a realidade de maneira satisfatória. As informações quantitativas fornecidas pelo modelo são de grande utilidade na elaboração de projetos de melhoria das características das laterais de rodovias existentes, bem como na preparação de projetos de novas rodovias. / A significant portion of road traffic accidents on highways occurs because of the exit of vehicles from the runway, which may result in collisions with fixed obstacles, falls in empty spaces, overturning, roll over, etc. This kind of accident is in general quite severe, due to the high speeds on highways. Approximately one third of road accidents with fatalities in the United States result from the runway exit. In Brazil, it is estimated that 30% of road accidents are also related to the runway exit, bringing this value at 25% in the cases of accidents with fatal victims. The QRRE that stands for Quantification the Risk in the Runway Exit of vehicles on highways is presented in this research. The model allows to quantify the level of protection in each particular segment of the highway (microscopic analysis) and from this information, it permits to quantify the level of protection considering long segments (macroscopic analysis). In the developed model, the assessment is done considering separately the left and right sides of the runway, and the results can be compounded in the case of long segments quantification. The model was developed for the case of multilanes highways in each direction, however, this model can also be used in the case of two lanes highways with two-ways direction. The QRRE model allows to determine parameters that are not provided by the methods ABNT (2007) - Brazilian standard, - and AASHTO (2002) - American standard, which provides a better measurement of risk in the exit of vehicles from the runway. The results obtained by QRRE model show that it clearly represents the reality. The quantitative information provided by the model are useful for the development of projects in order to improve the characteristics of the roadside highways available, and the development of projects for new highways.