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.

In response to global climate change, Transport Canada has initiated a Climate Change Adaptation Study in order to provide an opportunity to improve knowledge of the impacts of climate change on transportation infrastructure in Northern Canada. In particular, this research aims to identify ways to mitigate the impacts of climate change on pavement surface friction characteristics at a project specific location: Runway 07-25 of Kuujjuaq Airport in Nunavik, Québec. This site was chosen because it is a complex site with highly variable soil conditions. Runway 07-25 is one of the busier runways in Nunavik and its traffic includes jet airplanes. The runway is also exposed to extensive winter maintenance activities. In addition, Runway 07-25 is considered a short runway and has a crossfall instead of crown for surface drainage. Increasing ambient temperatures have already led to a deeper active layer over permafrost, which affects overall runway performance. Climate change is especially evident in the winter months with large temperature fluctuations resulting in increased freeze thaw cycles. The site is, therefore, a good location to study solutions to climate change impacts, which are expected to affect other Canadian airports in the future. Kuujjuaq Runway 07-25 is of paramount importance to the community of Kuujjuaq, other communities in Nunavik, and communities north of Nunavik. It serves as a regional hub between the south, Nunavik’s communities and Iqaluit to the north, and provides an essential link for emergency evacuations, personal and business travel, as well as the transportation of basic food items. Globally, amongst the groups, the most affected by the impacts of climate change are the Inuit communities in Nunavik. Scientists and residents of these communities are witnessing growing evidence of the impacts of accelerated warming in this region, which is expected to continue into the future. In this research, runway texture and friction are assessed on Runway 07-25, as increased winter maintenance activities resulting from climate change are thought to be reducing surface friction. Existing friction and texture measurement data from previous years, current laboratory testing results on samples of the existing asphalt concrete mix as well as current surface texture and friction measurement data from the runway have been analysed to study trends and characterize the runway in terms of its frictional resistance. Friction improving technologies/products are discussed for maintenance and future rehabilitation options.

At present runway congestion in the airline industry has reached a dangerously high level. The effects of this are very costly to all parties involved; US$5bn per year in Europe in 1989 alone. The problem demands urgent attention to accommodate the expected average growth in air transport of 6% per annum. up to the year 2000. It is becoming more and more obvious, however, that the construction of new runways is not a feasible option due to both political, environmental and physical space limitations within Europe. Alternative solutions are therefore required. In 1991 the European Regional Airlines Association, (ERA), produced a document entitled, 'The Vital Link', which outlined a number of ways in which regional aircraft could use their performance differences from the larger jet aircraft to help generate extra runway capacity from existing runways. Whilst the author was a member of the ERA operations committee he developed some of these ideas further. It is the objective of this thesis to examine the ideas developed by the author from both a theoretical and practical point of view to determine the feasibility of implementing them at congested European airports. Theoretical simulation modelling of Manchester, Zurich and Gatwick airports was undertaken using the FAA SIMMOD airport and airspace simulation model. This produced delay time savings and changes to peak hour movement rates which were used in a cost benefit analysis model to see whether or not the procedure would make a cost saving. The practical side of the thesis focused on an industry questionnaire to regional airlines, major airlines and airports to obtain their views on the new procedures and case studies of the procedures at Manchester and Gatwick airports. Results of the work show that whilst the procedures can effectively reduce operating delays they have a lessor impact on peak hour movement rates. Optimum use of the procedures is unique to individual airports and depends on the runway operation mode, TMA airspace configuration and the type and variability of the traffic mix. Actual application of the procedures will be dependant on political and environmental restrictions and likely future changes in regional airlines aircraft fleets.

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.

No description available.

This work presents a novel real-time algorithm for runway detection and tracking applied to the automatic takeoff and landing of Unmanned Aerial Vehicles (UAVs). The algorithm is based on a combination of segmentation based region competition and the minimization of a specific energy function to detect and identify the runway edges from streaming video data. The resulting video-based runway position estimates are updated using a Kalman Filter, which can integrate other sensory information such as position and attitude angle estimates to allow a more robust tracking of the runway under turbulence. We illustrate the performance of the proposed lane detection and tracking scheme on various experimental UAV flights conducted by the Saudi Aerospace Research Center. Results show an accurate tracking of the runway edges during the landing phase under various lighting conditions. Also, it suggests that such positional estimates would greatly improve the positional accuracy of the UAV during takeoff and landing phases. The robustness of the proposed algorithm is further validated using Hardware in the Loop simulations with diverse takeoff and landing videos generated using a commercial flight simulator.

The objective of this study is to estimate the airport capacity in the National Airspace System (NAS). Previous studies have focused on the airport capacity of large commercial airports. This research study estimates the runway capacity for more than two thousand airports in the NAS in order to understand future tradeoffs between air transportation demand and supply. The study presented in this report includes capacity estimates for general aviation and commercial airports. To estimate airport runway capacity, the Federal Aviation Administration (FAA) Airfield Capacity Model (ACM) is used to assess the capacity at all candidate airports in a target airport set. This set includes all airports with potential Very Light Jet (VLJ) operations. The result of the study provides a broad view about the airport capacity in the future air transportation system, and could help decision makers with a modeling framework to identify congestion patterns in the system. Moreover, airport capacity is an important limiting factor in the growth of air transportation demand. The main motivation in our analyis is to include airport capacity constraints in forecasts of air transportation demand. The framework described in this report has been integrated into the Transportation Systems Analysis Model (TSAM). TSAM is a comprehensive intercity and multimode transportation planning tool to predict future air transportation demand. / Master of Science

<p> At present there is no code of practice or design guide for the complete design of crane run ways. Many sources o-f information apply to steel structures in general and do not address some of the more important design and practical aspects of crane runways. It is the purpose of this report to review the various standard procedures together with rules and guidelines which result from practical experience in design, construction and operation. In particular it is hoped to identify those questions around which there appears to be some uncertainty or lack of substantiation. Some of these topics are identified as areas for possible future research. </p> <p> The report considers the version components of the runway system and the loads which act on them. After discussion of the dynamic nature of loading and the allowances made for vertical and horizontal loads, the supporting system is described with reference to accepted guidelines, design details and sketches of connections. Interaction of the various components considers the design and detailing of the rail the girder, the horizontal girder (or surge plate) and columns and foundations. Use is made of a computer program to compare the behaviour of alternative girder support systems and the advantages and disadvantages of each is summarized. </p> / Thesis / Master of Engineering (MEngr)

No description available.

This thesis evaluates the potential recovery of the runway throughput under Wake Turbulence Re-categorization (RECAT) Phase II and Time-based Separation (TBS) with a Runway Occupancy Time (ROT) constraint comparing with RECAT Phase I. This research uses aircraft performance parameters (runway occupancy time, approach speed, etc.) from the Airport Surface Detection Equipment, Model X (ASDE-X) data set. The analysis uses a modified version of the Quick Response Runway Capacity Model (RUNSIM). The main contributions of the study are: 1) identifying the technical buffer between in-trail arrivals and regenerate them in RUNSIM; 2) estimate the percentage of the arrival pairs that have wake mitigation separation times in excess of ROT; 3) developed an additional in-trail arrival separation rule based on ROT; 4) measure the risk of potential go-arounds with and without the additional 95 ROT separation rules. 5) generate a sample equivalent time-based RECAT II. The study results show that the distributions of technical buffers have significant differences for different in-trail groups and strong connectivity to airport elevations. This is critical to estimate runway capacities and safety issues especially when advanced wake mitigation separation rules are applied. Also, with decreasing of wake separations, ROT will become a limiting factor in runway throughput in the future. This study shows that by considering a 95 percentile ROT constrain, one single runway can still obtain 4 or 5 more arrivals per hour under RECAT II but keep the same level of potential go-arounds compared with current operation rules (RECAT I). TBS rules seem to benefit more under strong wind conditions compared to RECAT I, and RECAT II. TBS rules need to be tailored to every airport. / Master of Science / This thesis evaluates the potential recovery of the runway throughputs by re-defining the minimum distance or time separations between successive arrivals. The minimum separation criteria between in-trail arrivals is defined by Federal Aviation Administration to avoid the wake vortex influence produced by the leading aircraft. The main contribution of this thesis lies in estimation of throughput capacity with the reduced minimum separation between arrivals. The study results show that the distributions of buffers added to the minimum separations have significant differences for different in-trail groups and strong connectivity to airport elevations. This is critical to estimate runway capacities and safety issues especially when advanced wake mitigation separation rules are applied. Also, with decreasing of wake separations, runway occupancy time will become a limiting factor in runway throughput in the future. This study shows that by considering a 95 percentile ROT constrain, one single runway can still obtain 4 or 5 more arrivals per hour under reduced minimum separation but keep the same level of potential go-arounds compared with current operation rules.