Development of a Runway Veer-Off Location Distribution Risk Assessment and Reporting Template (2014)

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78 A P P E N D I X D Runway Veer-Off Location Distribution Risk Assessment Model LRSARA User Guide Lateral Runway Safety Area Risk Analysis (LRSARA) Software User’s Guide (V1.1) developed by Airport Safety Management Consultants, LLC for the Airport Cooperative Research Program (ACRP)

LRSARA User Guide 79 Disclaimer While every precaution has been taken in the preparation of this analysis tool, the Airport Cooperative Research Program (ACRP) and Airport Safety Management Consultants, LLC (ASMC) assume no responsibility for errors or omissions, or for damages resulting from the use of information contained in this document or from the use of this software. In no event shall ACRP or ASMC be held liable for any loss of profit or any other commercial damage caused or alleged to have been caused directly or indirectly by the use of this software. The user shall be aware that the software should not be used without adequate knowledge of the contents of ACRP Report 107 and this User Guide for LRSARA Software. Analysis soft- ware contains a tool developed to assist with risk analysis associated with the lateral portion of runway safety areas and is not intended to be a substitute for the airport planner professional judgment. Neither ACRP nor ASMC shall be held liable for any death or bodily injury, damage to prop- erty or any other direct, indirect or incidental damages or other loss sustained by third parties which may arise as a result of customer use of the LRSARA software, nor for damage inflicted with respect to any property of the customer or any other loss sustained by said customer. Neither ACRP nor ASMC shall be responsible for the accuracy or validity of the data entered and/or generated by the software. Lateral Runway Safety Area Risk Analysis (LRSARA) User Guide – Version 1.0 1. Introduction This software is being developed as part of the Airport Cooperative Research Program (ACRP) Project ACRP 4-14, “Runway Veer-off Location Distribution Risk Assessment Model” and is intended to serve as a tool to help airport operators evaluate risk associated with their lateral RSA conditions. The risk associated with the following five types of aircraft accidents may be evaluated with this software: • Landing veer-off (LDVO) • Takeoff veer-off (TOVO) The user may perform two types of analysis with this software. In the first type of analysis, the user can evaluate the probability that the aircraft will exit the runway and stop beyond the lateral limits of the RSA. In the second type of analysis, the user may consider the obstacles inside or in the vicinity of the lateral sections of the RSA to evaluate the risk of an accident (substantial aircraft damage and/or multiple injuries/fatalities).

80 Development of a Runway Veer-Off Location Distribution Risk Assessment Model and Reporting Template 2. System Requirements Component Requirement Computer and processor 1.0 gigahertz (GHz) processor or higher Memory 2 megabyte (MB) RAM or higher Hard disk 1.5 gigabyte (GB); a portion of this disk space will be freed after installation if the original download package is removed from the hard drive Display 1024x768 or higher resolution monitor Operating system Microsoft Windows 7, or later operating system Other LRSARA utilizes modules from Microsoft Office Suite 2010, particularly Microsoft Access to handle the databases and Microsoft Excel to handle data input and output results. Therefore, the user must have Microsoft Office 2010 with Excel and Access to run LRSARA 3. Using the Guide To facilitate reading and comprehension of this user guide, please note the following styles and conventions used throughout: Menu Selection Analysis/Run Analysis means click on Analysis on the main menu and then click on Run Analysis in the Analysis sub-menu. Main Window The main window contains the top title bar with the main menu name and the Minimize, Maximize, and Close buttons. Movements Challenging the Lateral RSA In a given airport, any movement (landing or takeoff) may challenge the right or left side of the lateral portion of the RSA, in case of a lateral runway excursion (veer-off). Level of Risk Format The program provides results in scientific format (e.g., 2.3E-07 or 0.00000023). These results can also be read as number of movements to occur in one event. To read in this format, you have to take the inverse of the value in scientific format (e.g. 1/2.3E-07 = 4,347,826). In the example provided, a risk of 2.3E-07 is equivalent to one accident in 4,347,826 movements. 4. Software Installation The installation of LRSARA uses the same process applied to other Windows programs. Go to the folder where you downloaded (either from the TRB website or the accompanying CD) and unzipped LRSARA, and double click on setup.exe. Then follow the on-screen instructions to install the program. It will add the program to your program group and place a shortcut on your desktop.

LRSARA User Guide 81 If you want to install a new version to replace the existing one, you first need to remove LRSARA. To remove LRSARA, select Start/Control Panel in your desktop window. Select Add or Remove Programs. When the program list is populated, select LRSARA and click Remove. 5. Opening the Program To open LRSARA, double click on the shortcut to open the Disclaimer screen. Please read the disclaimer and if you accept the conditions, click I Accept, and the main screen will open, otherwise the program will be closed.

82 Development of a Runway Veer-Off Location Distribution Risk Assessment Model and Reporting Template Fill the fields as shown in the example below and click Create Project. The project name cannot have spaces. 6. Creating a New Project Click on File/New Project and the following screen will appear.

LRSARA User Guide 83 7. Entering Data Defining Airport Conditions The following screen will appear when you select the Create Project button or when you select Input Data/Airport Characteristics in the main menu.

84 Development of a Runway Veer-Off Location Distribution Risk Assessment Model and Reporting Template Enter the specific characteristics of the airport, including the characteristics of the runways and available distances. Each of the fields and commands are described in the table that follows. Field Description Example Meaning Elevation (ft) The airport elevation, in feet 1500 The highest point on any of the airport’s runways is 1,200 ft relative to sea level Expected Traffic Growth (%) The average expected annual growth for aircraft movements 2.0 The average annual growth for future years is expected to be 2.5% Airport Hub (Yes or No) If the airport is a hub (large, medium or small), enable the check box If the box is checked, the airport is a hub Target Level of Safety (TLS) The acceptable level of risk is expressed in the form of a TLS or Criteria 1.0E-06 In this case, the acceptable level of risk is 1 accident in 1,000,000 movements, or 0.000001 (or 1.0E-06) accident per aircraft movement Assume Commuter Ops by Type of Aircraft? The frequency models use the type of flight (commercial, cargo, taxi/commuter, or GA). Sometimes the information on commuter flights is not available and if the check box is marked, the type of aircraft will dictate if the flight is commuter or not If checked, the program will assume commuter flights for every aircraft typically used for commuter operations. For example, ERJ-45 (Embraer jet airliner) For runway configuration, enter all the runways that will be evaluated. The analysis provides results for each runway and for all runways as the total risk for the airport. For the analysis, each runway direction is treated independently. To enter the runway information, click on Add RWY to enable the runway fields. The information required follows. Field Description Example Meaning RWY ID Enter the runway designation 15 This is the designation for runway 15 ASDA (ft) Accelerate-Stop Distance Available for takeoff, in feet 11800 Runway 15 has an ASDA of 11,800 feet LDA (ft) Landing Distance Available, in feet 11650 Runway 15 has an LDA of 11,650 feet. This distance is automatically calculated based on the ASDA and Displaced Threshold Displaced Threshold (ft) Distance that threshold is displaced for landing 150 Runway 15 has a displaced threshold of 150 ft Approach Category Type of instrument approach available I Runway 15 approach category is precision level 1. Other possibilities are: V (visual), NP (non-precision), CAT II and CAT III Once the runway fields are filled, save the information by clicking Save RWY. You may con- tinue adding the basic information for each runway before defining the RSA geometry for the runway. Changes to runway declared distances can be made by clicking Update RWY and saving the changes.

LRSARA User Guide 85 For the Example Project, the information for runways 15 and 33 were entered and the follow- ing screen illustrates the example. Defining Lateral RSA Geometry and Obstacles Next, enter the RSA information, including the geometry and existing obstacles. To perform this step, click Edit RSA Geometric Layout and the following screen will appear.

86 Development of a Runway Veer-Off Location Distribution Risk Assessment Model and Reporting Template The dropdown list includes all runways entered. In the example above, runway 15 is selected. The screen contains one set of buttons to define the lateral RSA geometry and the presence of obstacles. The two fields for Lateral OFA Distance are used to define the distance from the runway edge (not from the runway centerline) to the farthest lateral distance to an existing obstacle limiting the available Object Free Area (OFA). The runway in the example is 150 ft wide, and the RSA limit is 300 ft from the runway edge. The first step is to define the lateral RSA geometry. This area helps protect aircraft veering off runways 15/33. The Lateral OFA Distance is the clearance from the runway edge to the nearest obstacle, fixed or movable. LRSARA assumes a ground-level obstacle as default to limit the Lateral OFA Distance. However, in some cases, the object may be a hangar or another fixed object and the user will be required to define a “wing-level” obstacle at the borders, for example, an aircraft located in a parallel taxiway. In this latter case, the Lateral OFA Distance will be assumed as the distance between the runway edge and the wingtip of the taxiing aircraft, as shown below. The location of the wingtip is associated with the Aircraft Design Group (ADG), or it may be the air- craft with the largest wingspan operating at the airport.

LRSARA User Guide 87 In the figure, WS2 is the wingspan of the taxing aircraft and WS1 is the wingspan of the aircraft in the runway. The available lateral distance will be automatically calculated as follows: SOFAD = CS-RW 2-WS2 2 Where: • SOFAD is the lateral cleared distance available • CS is the runway/taxiway centerline separation • RW is the runway width • WS2 is the wingspan of the aircraft in the taxiway, usually characterized by the largest wing- span of the ADG of the airfield The lateral cleared distance available to the right and to the left are not necessarily the same. In the example, the cleared distance on right side of Runway 15 is 250 ft measured from the runway edge, and the left side is 300 ft wide. LRSARA software takes into consideration the gear width of the aircraft landing or taking off to calculate the cleared distance in the default case. Again, if the user prefers to use a tall obstacle to limit the RSA, a tall obstacle should be placed over the entire distance of the runway, and located at the OFA edge. To define the RSA, click on New RSA and a dialog box prompting you to create a Microsoft Excel spreadsheet will appear, as shown below.

88 Development of a Runway Veer-Off Location Distribution Risk Assessment Model and Reporting Template It is recommended that you name the file for the runways chosen, for instance, the example used here would be 15/33 RSA. Click Save and the Excel spreadsheet will open, as shown in the following screen. The user should note that each layout will represent the runway in both directions; therefore, it is not necessary to create another template to input information for Runway 33. Initially, the spreadsheet contains an “empty” RSA with two lateral lines defining the RSA limits set in the previous step. The number on top of the runway figure represents the runway direction for the approach end. The template has only one folder (Main) and is used to define the RSA geometry, and locate existing obstacles. Please note the runway shown is only a representation to facilitate locating its position and may not be on the same scale as the RSA. On the top left portion of the template, appropriate scales (lateral and longitudinal) for representation of each cell are automatically set; the runway width will not match the coordinates used to define the RSA geometry.

LRSARA User Guide 89 The area is automatically defined based on the runway distance available and the lateral distance available making up the RSA. Two types of obstacles may be evaluated in the analysis: ground obstacles and tall obstacles. A ground obstacle is a structure below the ground level (e.g., ditches, uneven terrain, terrain drops, etc.). These obstacles may cause an accident if aircraft gears pass over it and in this case the landing gear dimensions are considered in the analysis. A tall obstacle is a structure above the ground that may lead to an accident if struck by the aircraft. In this case, the wingspan of the aircraft is considered in the analysis. Two codes are used to define the areas with obstacles: “g” and “w”. The letter “g” is used to represent ground-level obstacles and the letter “w” represents tall obstacles. For example, a 140-ft long ditch located on the right side of runway 15, 60 ft from the runway edge is shown below. A second obstacle categorized as “tall” (e.g., a hangar) is located on the left side of the runway, 200 ft from the runway edge as shown in the figure. The obstacle is 70 ft wide and 280 ft long. The longitudinal scale does not allow the user to enter the exact length of the obstacle and it is recommended to be conservative and use a length that is larger than the actual obstacle being represented.

90 Development of a Runway Veer-Off Location Distribution Risk Assessment Model and Reporting Template Use the Excel menu to save the RSA geometry for Runway 15/33, and close the spreadsheet. The action will take you back to the RSA Geometric Layout screen. When the RSA characteristics are entered for each runway available in the drop down list, you may click Done to exit the screen, taking you back to the Airport Characteristics Input screen. The program will automatically save the information entered. Historical Operations Data (HOD) The next step is to enter HOD. Ideally historical data for the airport should be collected for one year. The information is placed in the template spreadsheet for this type of data. The columns, the field, and the format to save this data in the spreadsheet are presented in Attach- ment A to this guide. To enter the historical data into the analysis, click Analysis/Input Data/ Historical Operations Data to open the screen to load the file. Please note that the HOD can be edited using Microsoft Excel, however, you should not change the name of column headers or the tab name that contains the data. LRSARA uses the labels to identify the type of data to load into the program. For towered airports, it is possible to retrieve the records for operational data from the tower log or from the FAA’s Aeronautical Information Management Lab. In some cases, the records are available; however, the runway used is not identified. For airports in the Aviation System Performance Metrics (ASPM), it is possible to identify the runway configuration used in an hourly basis. The information is available online at aspm.faa.gov. For non-towered airports, a sample of operations during one month may be repeated over the 1-year period of records for the analysis. The information will be matched to the weather data retrieved for the airport to create a representative sample for analysis.

LRSARA User Guide 91 The screen allows the user to create, edit, import, or view the HOD required to run the analysis. Historical Weather Data (HWD) The file containing the HWD data will be loaded using a similar process to that used to load the HOD. The period for the weather data must match the period for the operational data. The LRSARA program will match the operational and weather data to characterize the actual weather conditions for each operation. The preparation of weather data is described in Attach- ment B to this guide. It is important to note that the HWD can be edited using Microsoft Excel, however you should not change the name of column headers or the tab name that contains the data. LRSARA uses the labels to identify the type of data to load into the program. The screen to enter the file containing weather data is as follows.

92 Development of a Runway Veer-Off Location Distribution Risk Assessment Model and Reporting Template The screen allows the user to create, edit, import, or view the HWD required to run the analysis. The spreadsheet may be opened using LRSARA or directly in Excel and saved without changing the file name. Aircraft Library The software contains a basic database of aircraft that may be updated to run the analysis. Click Software Parameters/Aircraft Database to access the database. The following screen will appear.

LRSARA User Guide 93 You may edit, update, or add records by clicking the check box on the top left of the screen. Checking that box enables the fields for editing. It is important to note that LRSARA identifies the type of aircraft in the historical information by the aircraft FAA code shown in the third column. 8. Model Parameters The user may view the frequency and location models used in the program by clicking Soft- ware Parameters/Model Parameters. The model parameters cannot be edited. The frequency models incorporated into the software are those presented in ACRP Report 51, and the location models are those developed in ACRP Project 4-14 research. They will be available in this report, ACRP Report 107.

94 Development of a Runway Veer-Off Location Distribution Risk Assessment Model and Reporting Template This screen contains two tabs. The first shows the frequency models for landing veer-offs (LDVOs) and takeoff veer-offs (TOVO). The second tab presents the location models for longi- tudinal and transverse distances relative to the runway axis for the same types of events.

LRSARA User Guide 95 9. Running the Analysis The analysis menu has four submenus: • Check Analysis Status • Run Full Analysis • Run Simplified Analysis • Output Missing Data Check Project Status The user may select Analysis/Check Project Status to check the status of calculations for one or more runways. In the example presented, both the probability of veer-off and risk of accidents for runways 15 and 33 were estimated. Run Full Analysis This type of analysis requires the use of historical operations and weather information for the airport. The information is used to feed the frequency models for landing veer-offs and takeoff veer-offs presented in ACRP Report 50. To run the full analysis, select Analysis/Run Full Analysis, and the following screen will appear.

96 Development of a Runway Veer-Off Location Distribution Risk Assessment Model and Reporting Template You may run the analysis for individual runways or for all runways entered in the project. The selection is made on the top left of the screen, and if Run Individual Runway is selected, the list of runways is enabled for user selection. After selecting Run Individual Runway or Run All Runways, the user must select one of the following two buttons to run the analysis: • Probability of Incident-Frequency • Risk Analysis The analysis is conducted in two steps. First, click on Probability of Incident-Frequency. The program will only estimate the probability of veer-offs occurring for the runways selected. In this case, only the frequency model will be used to calculate the probability of veer-offs, no matter if the event resulted in an accident or not. The program will store the results internally, and this step will allow the user to identify missing data on the historical records. Running the Probability of Incident-Frequency is required before running the next steps. This step saves time when running the second step—when the actual RSA dimensions and obstacles will have an influence on the risk estimates. If you want to evaluate different RSA conditions, it will not be necessary to run the calculations with the frequency model again. The Risk Analysis button allows the user to consider the interaction between the aircraft and the obstacles present within the RSA or its vicinity. The analysis will consider the type, location, and size of the obstacles and will assume that an accident will occur when the aircraft strikes an obstacle. The lateral limits are assumed to be ground obstacles by default. When clicking the Risk Analysis button, please wait a few minutes before the progress bar is shown. The program is performing internal calculations before the progress bar is activated. The approach to estimate the risk of accidents uses the following assumptions: 1. Two categories of obstacles are defined as a function of obstacle height. a. Ground Obstacle: The width of aircraft landing gear is considered to estimate the prob- ability of collision with the obstacle (e.g., cliff at the RSA border, body of water, ditch, rough terrain, etc.)

LRSARA User Guide 97 b. Tall Obstacle: the aircraft wingspan is used to estimate the probability of collision with the obstacle (e.g., buildings, fences, aircraft, vehicles, etc.) 2. The lateral distribution is random and does not depend on the presence of obstacles. This is a conservative assumption because there are events for which the pilot may have enough directional control to avoid the obstacle. Run Simplified Analysis For this alternative, no information on historical operations and weather for the airport are required. The probability of veer-off is estimated from default or user-defined values, which are fixed for each type of veer-off: landing and takeoff. Default values are those presented in ACRP Report 51 however, the user may change the default values as necessary. To run the simplified analysis, select Analysis/Run Simplified Analysis, and the following screen will appear. Output Missing Data When running the analysis for a given runway for the first time, the program checks for miss- ing records, either aircraft or weather. The analysis cannot be completed for specific records that have missing information. One common occurrence is a record for an aircraft not being listed in the aircraft database. In most cases, the FAA code for the aircraft is a variation of the normal code; it is an aircraft that isn’t widely used and is not in the default aircraft database; or it is an aircraft with maximum takeoff weight lower than 5,600 lbs. If missing records were identified during the run, the following screen will appear.

98 Development of a Runway Veer-Off Location Distribution Risk Assessment Model and Reporting Template If the user selects Yes, an Excel spreadsheet will appear as shown below, showing the records with missing information. These records will be stored during the analysis and can be retrieved by the user at any time by clicking Analysis/Output Missing Data. The user may ignore the list of records with missing data if the list contains only a few records; however, it is possible to fix the problems with such records and rerun a faster analysis with only the missing records for all runways or individual runways. There are two ways to correct missing data for aircraft. If the information for the aircraft is not in the aircraft database, the user should click Software Parameters/Aircraft Database and add the aircraft information to the database. If the information is available and the code does not match the FAA code in the aircraft database, the user may simply edit the code by clicking Analysis/Input Data/Historical Operations Data and then Edit Existing Input File. Informa- tion on FAA codes for aircraft can be obtained from FAA Order JO 7110.65T (Feb 2010). All the mismatching codes should be replaced with the code matching the code available in the aircraft database. If weather data is missing, the user may correct the file by clicking Analysis/Input Data/ Weather Database and then Edit Existing Input File to make the necessary corrections. After the corrections are made, the user may run the analysis only for the revised records. This will save time, particularly for the analysis of larger airports with many historical records. To rerun the analysis for the revised records, the user must check the option Check to rerun fixed missing data in the Run Analysis screen. The estimates after rerunning the analysis will consider both the previous and the new analysis of records recovered.

LRSARA User Guide 99 In addition to checking missing data, LRSARA also checks inconsistencies in input data. The preliminary check is automated and is executed in the MS Excel templates used to create HOD and HWD. Prior to performing the calculations, LRSARA will recheck data to warn of data outside the expected ranges. An example of the message warning the user is shown below. If the user selects Yes to visualize inconsistent data, an MS Excel file will open, as shown in the following figures, for HOD and HWD, respectively.

100 Development of a Runway Veer-Off Location Distribution Risk Assessment Model and Reporting Template The user should correct the inconsistent data before running the risk analysis; otherwise the analysis will not be completed. 10. Output Results When the analyses are completed, the user may see the results using the Output option of the main menu. There are two types of results: individual runways or the consolidated results for the whole airport. Within each of these options, the user can view the results for risk of events taking place outside the RSA or view the analysis output for the risk of catastrophic accidents. Results for Runways To see the results for all or individual runways, select Output/Runway and the following screen will appear.

LRSARA User Guide 101 The output file for the selected runway or all runways is created by clicking Create Output for Risk Analysis. The results are stored internally in the program. Creating the output in this step is necessary to transfer the data to an Excel spreadsheet to facilitate visualization of results. Since this screen is for runways, the user may select one specific runway to output results, or see the results for all the runways. In the latter case, the number of spreadsheets created will be the same as the number of runways analyzed. The spreadsheets created will open automatically when creating the output files. If the user has run the analysis and created outputs, the files can be opened by clicking Open Existing RSA Outputs, and selecting the desired file.

102 Development of a Runway Veer-Off Location Distribution Risk Assessment Model and Reporting Template Results are presented in both tabular and graphical format. Each set of results contains the risk estimates for each type of incident and individual operation and the total risk during landings and takeoffs. A summary of the results is presented in the Summary tab shown in the previous screen. The summary table is shown below. It is very important to understand the information contained in the three tables shown. The first table contains the Airport Annual Volume and the expected Annual Traffic Growth Rate, and these values may also be modified by the user in the output spreadsheet. By changing these values, the average number of years between incidents will also change to reflect the new volume of traffic estimated for future years. The second piece of information, the Target Level of Safety (TLS), may also be modified in the spreadsheet and the value will impact the percent- age of movements above the TLS (4th column in the large table). Airport Annual Volume: 50,000 Expected Traffic growth rate: 2.00% Target Level of Safety (TLS): 1.0E-06 The second table titled Veer-Off Risk for Movements for the selected runway contains results for veer-off only. This is necessary because it is a different area and is composed of the lateral safety areas between the runway ends. The configuration of this table is similar to the one pre- senting the results for the RSA (second table).

LRSARA User Guide 103 The histogram shown in the Summary tab contains the probability data for each movement challenging the lateral RSA. Similar histograms for each individual type of operation (landing and takeoff) are available in the Plots tab. Results for the Airport To see the results for the airport as a whole, select Output/Airport and the following screen will appear. Veer-Off Risk for Movements on RWY 15 Incident Average Probability Avrg # of Years to Incident/ Accident % Movements Above TLS Avrg # of Years to Critical Incident for TLS LDVO 2.2E-07 >100 6.7 52 TOVO 5.6E-08 >100 0.2 45 Total 1.3E-07 99 3.1 30

104 Development of a Runway Veer-Off Location Distribution Risk Assessment Model and Reporting Template Again, it is necessary to create the output if this procedure has not been performed earlier. The user may select the type of output and click Open Existing Airport Summary to view the results in a spreadsheet as shown in the screen below.

LRSARA User Guide 105 The tables are similar to those presented for individual runways, except that results for all types of incidents/accidents are consolidated and data for individual risk for any type of event are consolidated into the histogram. In addition, individual tables containing results for each runway are also presented. Similar to the output for individual runways, the spreadsheet also provides a Plots tab con- taining histograms for individual types of incidents/accidents for the airport as a whole. An example of the first table is shown below. It contains in the second column the average probabilities for each type of event and the total average probability for the airport. In the third column, the average number of years between incidents or accidents is calculated. This number is estimated based on the event probability, the annual volume of operations challenging the RSA for the given event, and the expected growth rate. Please note that this number is not to predict how many years it will take for that accident to happen; rather, it is an indication on how frequently the event can take place if the same conditions of operations are kept for a very long period of activity at the airport. The fourth column indicates the percentage of movements challenging the RSA that have a risk higher than the selected TLS (e.g., for LDVOs, 4.9% of the movements are under a risk higher than 1.0E-06, one in one million movements). Finally, column 5 contains the estimated number of years between events for the selected TLS. The results in this column are calculated using the same method used to estimate the results in the third column, except that the risk used is the TLS. The table immediately below has the airport volume of operations (annual number of move- ments: landings and takeoffs), the expected annual growth rate of traffic, and the selected TLS. These numbers can be directly changed in the spreadsheet and new values will be calculated for the third, fourth, and fifth columns of the main table. Overall Results Risk Analysis Summary Table LDVO 2.0E-07 81 5.1 30 TOVO 5.8E-08 >100 0.3 30 Total 1.2E-07 73 0.1 17 Accident Average Risk of Accident Avrg # of Years to Critical Incident % Ops Above TLS Avrg # of Years to Critical Incident for TLS Airport Annual Volume: 50,000 Expected Traffic growth rate: 2.00% Target Level of Safety (TLS): 1.0E-06 Below the main table, a plot with the total distribution of risk is shown. Data used for this plot are originated from each type of event and two results are presented. Each bar that makes up the histogram of risk represents a given risk level as shown in the x-axis. The number of operations for each bar is read on the left y-axis. The segmented line is associated with the right y-axis and indicated the percentage of movements that have a risk higher than the value read

106 Development of a Runway Veer-Off Location Distribution Risk Assessment Model and Reporting Template in the x-axis [e.g., approximately 20% of movements are subject to risk higher than 1.7E-07 (or one event in 5,880,000 movements)]. 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% 0 100 200 300 400 500 600 700 800 900 Cu m ul at iv e % O ps Fr eq ue nc y of O ps Probability Interval Histogram of Total Risk Frequency Cumulative % Additional tables are shown on the right of the main table. The first table presents the prob- ability of runway veer-offs for each runway and each type of operation. Summary of Results by Runway Probability of Event per Operation 15 33 LDVO 5.78E-07 5.54E-07 TOVO 1.21E-07 1.55E-07 Type of Accident RSA The second table presents the average risk level for each type of event and the associated runway direction challenged by the movements. Risk of Accident in Events per Operation 15 33 LDVO 1.95E-07 2.07E-07 TOVO 5.37E-08 6.21E-08 Type of Accident RSA

LRSARA User Guide 107 The next table presents the average number of years for one accident to occur if the opera- tional conditions are similar during a long period of activity. Similar to the previous table, the results are provided by runway direction challenged by aircraft movements at the airport. Average # of Years Between Accidents 15 33 LDVO >100 >100 TOVO >100 >100 Type of Accident RSA Percent Events Above 1.0E-06 Type of Accident 15 33 LDVO 5.59 4.67 TOVO 0.18 0.38 RSA Summary of Operaons Challenging the RSAs Movements Challenging each RSA 15 33 LDVO 447 471 TOVO 548 520 Total 995 991 RSA Type of Accident The fourth table in the group shows the percentage of movements challenging each runway direction that are subject to risk level higher than 1 accident in 1 million operations. The final table shows the total number of movements that challenge each runway direction. These values are based on the HOD sample used for the analysis.

108 Development of a Runway Veer-Off Location Distribution Risk Assessment Model and Reporting Template Below is an example output for simplified analysis. For this case the probability of accident will depend only on the category of aircraft and no histogram of risk is generated. The user may change the percentage of operations for each category of aircraft directly in the spreadsheet and the average risk results will change accordingly. There is no need to use the Output submenu to obtain the report for simplified analysis; the file with the results will open automatically upon completion of the analysis.

LRSARA User Guide 109 11. Help and Troubleshooting The last option in the main menu is Help. When selecting this option Help/Content, a pdf version of this User Guide will open. If the user selects Help/About, the following screen will be presented.

110 This section describes the procedure to prepare historical operations data for the airport. The historical operations data provided is consolidated internally in the program with the weather information provided (see Attachment B). The process is used to characterize the sam- ple operations for the airport and weather conditions to which these operations were subject. Ideally a sample of data covering one full year of recent operations should be prepared to run the analysis. Having one year of data will help take into consideration seasonal weather and operational variations. A Microsoft Excel (2010 or later) spreadsheet is used to enter the Historical Operations Data and create the sample. To create this database, select Input Data/Historical Operations Database and the following screen will open. Historical Operations Data A T T A c h M e n T A

LRSARA User Guide 111 To create the operations file, click on Create New Input File and a dialog box will open. Please enter a file name and the Excel spreadsheet will open with eight columns as shown below.

112 Development of a Runway Veer-Off Location Distribution Risk Assessment Model and Reporting Template Each line in the spreadsheet should correspond to one record. The following table contains a description of each field. Field Description Format HOD_ID This is an ID for the record and any reference may be used by the person creating the database. We suggest entering a number, starting from 1 to the last record number, as shown in the example below. Any format may be used. This information is not used by the program and is intended only to be a reference for the user. DATE&TIME This is the date and time when the aircraft movement took place. The fixed format includes date and time, and is already set in the template provided with the program. Please see example below. RWY_DESIGNATION This is the runway designation where the movement took place. The runway number and letter should be included (e.g. 15 or 23). BOUND If the movement is an arrival or departure. Use A for arrival and D for departure. FLIGHT# The flight number for the movement. Any format can be used (e.g., AAL622). This information is for user reference only and does not need to be filled in because the program does not require it. FAA_CODE This is the code used by the FAA to characterize the aircraft type and model. The code must match those available in the aircraft database. For example B733 is used for the Boeing 737-300 aircraft. When running the analysis, the program will attempt to match this code to one of the codes in the aircraft library. If the program is unable to match to an existing aircraft code, the record will be saved in a file for missing data and later the user can insert the new aircraft in the database and rerun the analysis for missing data records. FLIGHT_CATEGORY This field is used to characterize the type of flight: commercial, cargo, commuter/taxi, or general aviation (GA). Use AIR for commercial, CAR for cargo, COM for commuter/taxi, and GA for general aviation. FLIGHT_TYPE This is a code used to characterize if the flight is arriving from or departing to an international destination. Use D for domestic and I for international.

LRSARA User Guide 113 An example of the template filled with the information needed to run the program is shown below.

114 Development of a Runway Veer-Off Location Distribution Risk Assessment Model and Reporting Template If the date and time format is not matching the format presented in the example above, the user may adjust by selecting the column, right-clicking, and selecting Format Cells. In the dialog box, select Date in the Category box and selecting 3/14/01 1:30 PM in the Type box, as shown in the screen below.

115 This section describes the procedure to prepare historical weather data for the airport. The historical weather data provided are consolidated internally in the program with the historical operations information provided (see Attachment A). The process is used to characterize the sample operations for the airport and weather conditions that these operations were subject. The period for weather data must match the same period for historical operations data. Having one year of data will help take into consideration seasonal weather and operational variations. A Microsoft Excel (2010 or later) spreadsheet is used to enter the Historical Operations Data and create the sample. To create this database, select Input Data/Weather Database and the following screen will open. Historical Weather Data A T T A c h M e n T B

116 Development of a Runway Veer-Off Location Distribution Risk Assessment Model and Reporting Template To create the weather file, click on Create New Input File and a dialog box will open. Please enter a file name and the Excel spreadsheet will open with nineteen columns as shown below.

LRSARA User Guide 117 Each line in the spreadsheet should correspond to one record. The following table contains a description of each field. Field Description Format Date&Time This is the date and time when the weather measures were taken. The format includes date and time, and is already set in the template provided with the program. Visibility_NM The average forward horizontal distance that a prominent unlighted object can be seen and identified by day from the cockpit of an aircraft in flight. Nautical Miles (NM) Wind Direction_deg The true direction from which the wind is blowing at a given location (i.e., wind blowing from the north to the south is a north wind). A wind direction of 0 degrees is only used when wind is calm. In degrees clockwise through 360 degrees. North is 360 degrees. Wind Speed_knots The rate at which air is moving horizontally past a given point. It may be a 2-minute average speed (reported as wind speed) or an instantaneous speed (reported as a peak wind speed, wind gust, or squall). Knots (kt) Air Temp_F The ambient temperature indicated by a thermometer exposed to the air but sheltered from direct solar radiation. Degrees Fahrenheit (F) Ceiling_ft The height of the cloud base for the lowest broken or overcast cloud layer. Feet (ft) Thunderstorm A local storm produced by a cumulonimbus cloud and accompanied by lightning and thunder. Presence (TRUE) or not (FALSE). Rain Precipitation that falls to earth in drops more than 0.5 mm in diameter. Presence (TRUE) or not (FALSE). Rain Showers A brief period of rain. Presence (TRUE) or not (FALSE). Freezing Rain Rain that falls as a liquid but freezes into glaze upon contact with the ground. Presence (TRUE) or not (FALSE). Freezing Drizzle A drizzle that falls as a liquid but freezes into glaze or rime upon contact with the cold ground or surface structures. Presence (TRUE) or not (FALSE). Snow Precipitation in the form of ice crystals, often agglomerated into snowflakes, formed directly from the freezing [deposition] of the water vapor in the air. Presence (TRUE) or not (FALSE). Snow Pellets Precipitation, usually of brief duration, consisting of crisp, white, opaque ice particles, round or conical in shape and about 2 to 5 mm in diameter. Same as graupel or small hail. Presence (TRUE) or not (FALSE).

118 Development of a Runway Veer-Off Location Distribution Risk Assessment Model and Reporting Template Field Description Format Ice Pellets Same as sleet; defined as pellets of ice composed of frozen or mostly frozen raindrops or refrozen partially melted snowflakes. These pellets of ice usually bounce after hitting the ground or other hard surfaces. Heavy sleet is a relatively rare event defined as an accumulation of ice pellets covering the ground to a depth of ½" or more. Presence (TRUE) or not (FALSE). Ice Pellet Showers Short duration of ice pellet precipitation. Presence (TRUE) or not (FALSE). Fog Fog is water droplets suspended in the air at the Earth's surface. Fog often degrades visibility. Presence (TRUE) or not (FALSE). Gusts A rapid fluctuation of wind speed with variations of 10 knots or more between peaks and lulls. Presence (TRUE) or not (FALSE). Ice Crystals A barely visible crystalline form of ice that has the shape of needles, columns, or plates. Ice crystals are so small that they seem to be suspended in air. Ice crystals occur at very low temperatures in a stable atmosphere. Presence (TRUE) or not (FALSE). Snow Showers Short duration of moderate snowfall. Some accumulation is possible. Presence (TRUE) or not (FALSE). (Continued). An example of the template filled with the information needed to run the program is shown below.

LRSARA User Guide 119 If the date and time format is not matching the format presented in the example above, the user may adjust by selecting the column, right-clicking and selecting Format Cells. In the dialog box, select Date in the Category box and selecting 3/14/01 1:30 PM in the Type box, as shown in the screen below.