Runway Safety Area Research Articles

활주로시단이설에 따른 착륙대 위험발생빈도 변화 연구

A runway safety area (RSA) is defined as the surface surrounding the runway prepared or suitable for reducing the risk of damage to airplanes in the event of an undershoot, overshoot, or excursion from the runway. The Runway Stripe is a defined area including the runway stopway, if provided, intended firstly to reduce the risk of damage to aircraft running off a runway, and secondly, to protect aircraft flying over it during takeoff or landing operations. This study used 2 RSA analysis models; RSARA and LRSARA. The analysis utilizes historical data from the specific airport and allows to take into consideration specific operational conditions to which movements are subject, as well as the actual or planned RSA conditions in terms of dimensions, configuration, and boundaries defined by existing obstacles. This study applied the RSA and LRSA risk assessment models to a domestic airport that do not meet the criteria required by standards for aerodrome physical characteristics. The airport is considering a method to secure the runway strip standard through the displaced threshold. This study intends to confirm through quantitative risk estimation whether meeting facility standards through the runway displaced threshold leads to a positive change in risk mitigation.

Developing an anisotropic material for Engineered Material Arresting System (EMAS) usage

ABSTRACT An Engineered Material Arresting System (EMAS) is a bed of crushable material located at the end of an airfield runway within the runway safety area (RSA). An EMAS promotes aircraft stoppage during an aircraft overrun event. Typically, EMAS installations consist of isotropic cementitious material blocks. In contrast, this article explores the potential for using a light-weight anisotropic plastic material composed of unidirectional tubes (honeycomb configuration) as an alternative EMAS material. During this study, a number of laboratory tests were conducted to characterise the stress–strain behaviour of the proposed material. The material testing considered multiple force incidence angles with respect to the material tube orientation. These anisotropic material characterisation results were used as input to a numerical model for determining aircraft performance within an EMAS. The calculated performance results were then compared with the aircraft performance within the EMAS considering other potential EMAS isotropic materials. The results suggest that the compressive strength of the proposed anisotropic material needs to be reduced in order to compare well with those of other potential isotropic materials. The present article analyzes overrun events with the anisotropic material internal tubes oriented parallel to the aircraft motion direction.

Investigation of foamcrete mechanical and physical properties

Engineered Material Arresting Systems (EMAS) serve as a substitutional alternative/solution to airport runways when the Runway Safety Area (RSA) does not meet international Federal Aviation Administration (FAA) standards. The length of the runway can be shortened if an EMAS is installed on both ends of the runway. This paper provides experimental test results on foamcrete material used for such an important safety application. The objective of the paper is to present the required and measured properties of foamed concrete (density, compressive strength and water absorption) and results of an evaluation of a first phase of testing. In this study, a total of fourty eight mixes were conducted; yielding a range of densities, compressive strength(s) and water absorption characteristics that are: 554 to 1528 kg/m3, 1.1 to 21 MPa and 7.4 to 28.3 %, respectively. It is demonstrated herein – though the Analysis of Means statistical method – that foam volume is predominantly the main factor affecting the observed output characteristics. This is followed by Sand/Filler and Filler/Cement that yield marginal effect compare to the former foam volume ingredient.

Investigating the potential of using glass foam for an EMAS material to mitigate aircraft overrun accidents

ABSTRACT An aircraft overrun occurs when an aircraft is unable to stop within the runway design length. Commercial airports are required to have a 305 m (1000-ft) runway safety area (RSA) at each runway end to avail an aircraft adequate length for stoppage during an overrun. At airports where this space is unavailable, the Federal Aviation Administration (FAA) allows for an airport to use an Engineered Materials Arresting System (EMAS). An EMAS is positioned within the RSA and is comprised of an energy absorbing material that brings the aircraft to stoppage through drag forces developed at the tire-EMAS interface. EMAS are constructed using low-density 1.21 m × 1.21 m (4-ft × 4-ft) variable thickness cementitious blocks. The blocks are aligned adjacent to one another to form a rectangular EMAS bed within the RSA. This article presents the computer code, SGAS, developed by the author to predict aircraft stopping distance and behaviour of current aircraft types within an EMAS. The SGAS computer code is validated with results from the FAA ARRESTOR computer code. After validating the SGAS computer code, this article investigates the potential for using glass foam blocks as an alternative EMAS material.

Quantitative Risk Assessment of Temporary Hazards and Maintenance Worksites in the Airport Safety Areas: a case study

Abstract Airports are complex environments where the operational conditions are subjected to different risks, both due to the intrinsic nature of the manoeuvres themselves and to the external factors, as for human actions or environmental causes. An important risk factor is the presence of temporary hazards on the runway or taxiway safety area, including work in progress related to maintenance or construction operations. Both ICAO (International Civil Aviation Organization) and FAA (Federal Aviation Administration) defined their own approach on this topic. The FAA, in the Advisory Circular “Operational Safety on Airports During Construction”, states the impossibility of any construction activities within the safety area when the runway is active, while the ICAO, in the Doc 9137 “Airport Service Manual” Part 6, states specific operational restrictions for the airport which allow the presence of temporary hazard in the safety area. This paper analyses the impact of temporary hazards (for example worksites) in the safety areas, according to ICAO requirements, by using a performance approach. The method has been applied to an international airport, using the software RSARA e LRSARA, provided by ACRP (The Airport Cooperative Research Program), in order to calculate the expected risk level within the safety area. This method provides a rapid and practical evaluation of risk level, according to the ICAO Safety Management System approach, in order to optimize the maintenance operation and construction in the safety area, minimizing the closing time of the runway. The main aim of this study is to verify if, under temporary restrictive operational condition (such as the limitation on available runway length and on traffic mix and weather conditions) related to the temporary hazard presence, it is possible to guarantee sufficient safety level, without occurring in runway closures. From the analysis arose that the first factor that affects the risk level for a runway is the temporary hazard dimension: while the environmental conditions (crosswind and pavement conditions) have a minor effect.

Sensitivity analysis of influencing factors in probabilistic risk assessment for airports

Risk assessment methods in aviation greatly rely on the knowledge of the factors influencing risk and safety during daily operations. One of the weak points of the common approaches in aerodromes is the qualitative method to support decisions respect to quantitative evaluations. In this study, three airports with diverse characteristics (i.e.; aircraft annual movements, airfield geometry, and runway features) were selected for the analysis.The RSARA© (Runway Safety Area Risk Assessment) software, which is based on the Aircraft Cooperative Research Program (ACRP) model, has been utilized as a starting point for further sensitivity analyses of probabilistic risk assessment of each airport’s runway with determined casual factors, including runway geometry, traffic characteristics, and weather conditions. A comprehensive airports incident/accident database between years 2000 and 2015 was also used to perform the sensitivity analyses.By providing different independent variables as input in the frequency model of RSARA, the outputs were useful to determine the influence of each of the casual factors on the accident probability of occurrence. Selected variables include: runway length in terms of declared distances, Runway Safety Area geometry, instrumental landing system category, weather operational data and annual traffic growth rate. The sensitivity analyses showed that the weather condition and runway related factors played a major role in increasing or decreasing the probability of the accident; the probability of landing overrun (LDOR) can be increased by four times, for instance, due to specific combinations of runway length and climatic conditions. Engineered arrestor beds such as EMAS also has the potential to decrease by 50% the risk of LDOR and can be selected as an effective choice compared to other pavement materials within the RSA.Identifying critical variables on the occurrence of high-severity runway accidents could influence the aerodrome design, operating scenarios, regulations, emergency planning and risk management measures and techniques.

Managing safety and wildlife at Jackson Hole Airport

Jackson Hole Airport is the only US airport located wholly within the boundaries of a national park, and all airport activities must be performed in accordance with the regulations and policies set out by numerous agencies. Located in a pristine wilderness area, the airport includes habitat for many important species, including a lek (seasonal breeding area) for the greater sage-grouse within the runway safety area. The FAA Wildlife Strike Database identified numerous strikes with the sage-grouse, which had been identified as a candidate species for federal protection under the Federal Endangered Species Act. When the FAA required Jackson Hole Airport Board to prepare a Wildlife Hazard Management Plan, the Airport Board understood that the plan would have to satisfy the requirements of numerous federal, state and local agencies while remaining sensitive to local sage-grouse conservation efforts. The board embraced the challenge and developed a collaborative process involving agencies, researchers and consultants. The resulting Wildlife Hazard Management Plan provided a triple win for the agencies, the sage-grouse and the travelling public.

Jet Stopping Distance and Behavior in a Regional Airport EMAS

AbstractAn aircraft overrun occurs when an aircraft is unable to stop within the design runway length. To promote safety at United States airports, the Federal Aviation Administration (FAA) requires airports to have a runway safety area extending 1,000 ft (304.8 m) beyond both ends of the runway. However, in some cases natural or manmade barriers prevent satisfying this requirement. For these cases, one solution is to install an engineered materials arresting system (EMAS). An EMAS is a passive system constructed using low-strength cementitious blocks. Typically, an EMAS is designed for the heaviest aircraft based at the airport. Heavy aircraft fully crush the EMAS material and therefore their behavior within an EMAS is predictable. However, the National Plan of Integrated Airport Systems (NPIAS) includes many regional airports, which are supported by lightweight regional jets. Regional jet behavior within an EMAS differs from heavier aircraft. This paper investigates the EMAS performance and aircraft beh...

Runway Safety Areas

This article is focused on areas around runway and their dimensions for safety reason of air accidents and incidents. There is proposed new calculation of these dimensions.

The deceleration of aircraft in overrun accidents from the point of first impact to the end of the wreckage path

Purpose: This paper outlines previous attempts to model aircraft deceleration and using a newer database containing a greater number of observations tries to refine the model. Design/Methodology : It is noted that data inadequacies still necessitate the estimation of a given acceleration for the aircraft wreckage path, but that there are more opportunities to change the intercept in a regression model to reflect categorical and dummy variables that proxy factors such as runway condition, the degree of control exercised by the pilot during the crash, the speed at the point of first impact (hereafter POFI), headwind, rain, characteristics of the terrain on the wreckage path and aborted take-offs. Findings: The contribution of some of the explanatory variables can be seen. It is a shame other potential influences are not found to be significant. It is important to understand deceleration so that the wreckage location of aircraft accidents can be understood. This then gives guidance of appropriate runway safety areas. Originality/ value : This is the first time this has been attempted on the expanded accident database.

활주로안전구역 위험평가 개선모델 적용 연구

The RSA is intended to prevent the following five types of events from becoming an accident: landing overruns, landing undershoots, landing veer-offs, takeoff overruns and takeoff veer-offs. The improved models are based on evidence from worldwide accidents and incidents that occurred during the past 27 years. The analysis utilizes historical data from the specific airport and allows the user to take into consideration specific operational conditions to which movements are subject, as well as the actual or planned RSA conditions in terms of dimensions, configuration, type of terrain, and boundaries defined by existing obstacles. This paper shows how to apply the improved models for Risk Assessment of Runway Safety Areas (Airport cooperative research program(ACRP) Report 50) into an airport and the outcome differences between the old models based on ACRP report 3-Analysis of aircraft overrun and undershoots for runway safety areas and the new models from ACRP report 50 in the specific airport.

Topological risk mapping of runway overruns: A probabilistic approach

The paper presents a topological risk mapping for aircraft overruns. The proposed procedure is based on the study published in 2008 by Hall et al. (Analysis of aircraft overruns and undershoots for runway safety areas. Airport Cooperative Research Program. Washington, DC: Transportation Research Board; 2008). In that study the authors performed an analysis of aircraft overruns and undershoots for runway safety areas proposing the ACRP hazard probability model. In the present study the model was integrated into a two-step Monte Carlo simulation procedure to assess the risk of overrun accidents and to provide a topological risk map for a specific airport area. The model was modified to utilize traffic-related and weather-related factors described by statistical distributions of historical data of the airport under analysis. The probability distribution of overrun events was then combined with the Longitudinal and Lateral Location models Hall et al. (Analysis of aircraft overruns and undershoots for runway safety areas. Airport Cooperative Research Program. Washington, DC: Transportation Research Board; 2008) to obtain a two-dimensional grid assessing the probability of each area to be the end point of a runway overrun. The expected kinetic energy of the aircraft in a given point of the grid is used as severity index. The procedure is suitable for generalisation and it allows a more detailed planning of Airport Safety Areas (ASA), improving the correct implementation of ICAO recommendations. Results are also useful for land planning and structural analyses in airport areas.

Foamed Concrete-Based Material as a Soft Ground Arresting System for Runways and Airfields

AbstractA soft ground arresting system (SGAS) is an alternative solution on airport runways where the runway safety area (RSA) does not meet international Federal Aviation Administration (FAA) standards. If an SGAS is installed on both ends of the runway, the length of the runway can be shortened. In this paper the options of using foamed concrete as the arresting bed material in an SGAS are investigated. Tests were conducted on the foamed concrete to determine whether it has the ability to withstand support vehicle loadings, while failing underneath loading from an overrunning aircraft. The objective of this paper is to present the required and measured properties of foamed concrete and results of an evaluation into its possible implementation as an SGAS as an alternative to engineered material arresting system (EMAS) on airports. The following conclusions are drawn. Foamed concrete properties allow it to be used as a possible arresting material, with the unit weight/density of foamed concrete the most i...

Improving safety of runway overrun through the correct numerical evaluation of rutting in Cleared and Graded Areas

Aircraft overrun is potentially very dangerous to human life. Statistics show that overrun is mainly due to human errors causing loss of control in wheel alignment, high approach speed, and long touchdown. To prevent such disastrous consequences, advanced material arresting systems are currently being used in the main international airports for construction of Runway Safety Areas (RSAs). Many predictive models have been developed for controlling overrun events: the early reliable numerical models, on the basis of theoretical streamlined assumptions, were gradually replaced. More rigorous models based on Multibody System (MBS) and Finite Element Method (FEM) theories are nowadays much more preferred. These are characterized by high levels of reliability, even though the large number of data required does not always allow an exhaustive description of the domain of analysis. The paper presents an alternative method for predicting rut depths induced by aircraft overrunning. Such method is based on a numerical streamlined model, integrated with measurements from Light Falling Weight Deflectometer (LFWD), to define, section by section, the mechanical properties of soils in Cleared and Graded Areas (CGAs). The method has been validated through in situ tests, showing its high effectiveness and efficiency.

경량항공기 활주로안전구역에 대한 연구

In this study, we surveyed the operating status of the Runway for the Light Sport Aircraft(LSA) in Korea, and analyzed the Airfield Facilities Manual for the Air Leisure and the Standard Specification for Recreational Airpark Design. Based on the information, we presented the displacement of the threshold concept, to ensure the Runway Length and the Runway Safety Area, and operation of LSA in Korea.

Modelling the location and consequences of aircraft accidents

Following the completion of two projects funded by the UK EPSRC and two for the Airports Cooperative Research Program, ACRP (2008, 2011), this paper aims to summarise the work on the location and consequence models.5The expertise for implementing these models rests with Airport Safety Management Consultants.5 The projects overall focused on the development of an improved airport risk assessment methodology aimed at assessing risks related to aircraft accidents at and in the vicinity of airports and managing Runway Safety Areas (RSAs) as a risk mitigation measure. The improved methodology is more quantitative, risk-sensitive, flexible and transparent than traditional risk assessment approaches. As such, it contributes to the implementation of Safety Management Systems at airports, as stipulated by the International Civil Aviation Organisation. The innovative elements of this research are twofold. First, an accident database covering undershoots, overruns, and veer-off crashes close to runways at airports has been compiled and data on incidents has been added. Second, accident frequency models have been developed, for example, identifying the contribution of influencing factors such as variations in meteorological conditions. To allow airport risk to then be calculated entails comparing these cases with those contained in a ‘normal operations database’ where no accidents have been recorded but where the influencing factors are also known. Subsequent models have examined the location of the accidents and their consequences. It is this work that is the focus of this paper. Future work will focus on improving these aspects of the modelling and the consequences of crashes more than 2000ft. but less than 10miles from a runway end as well as impacts on third parties.

Aircraft Response in an Airfield Arrestor System during an Overrun

Air transportation has an overall outstanding safety record. However, accidents do occur. If an aircraft is unable to stop within the runway length, the incident is described as an overrun. To provide passenger safety during an overrun, the Federal Aviation Administration (FAA) requires airports to have a 305 m (1000 ft) runway safety area. At airports that are unable to satisfy this requirement, because of either natural or man-made barriers, the FAA allows the use of a shorter runway safety area with a properly designed arrestor bed. A sensitivity analysis is presented in this paper to investigate critical parameters in the design of an engineered-materials arrestor system (EMAS). A single arrestor-bed configuration is used as a base case for considering a low-density concrete EMAS material. Five aircraft types are considered, ranging from 51,700 kg (114,000 lbs) to 322,100 kg (710,000 lbs) maximum-certificated takeoff weight. These aircraft types include aircraft with various landing-gear configuration...

The development of probabilistic models to estimate accident risk (due to runway overrun and landing undershoot) applicable to the design and construction of runway safety areas

The risks of landing overrun (LDOR – LanDing OverRun), Take-off Overrun (TOOR – Take-Off OverRun) and landing undershoot (LDUS – LanDing UnderShoot) are dependent on multiple factors related to operating conditions. These include wind, runway surface conditions, landing or take-off distances required, the presence of obstacles, runway distance available, the existence and dimensions of runway safety areas. In this paper we propose risk models for runway overrun and landing undershoot, using a probabilistic approach. These models are supported by historical data on accidents in the area around the runway and will enable us to determine if the risk level is acceptable or whether action must be taken to mitigate such risks at a given airport. Furthermore, these models permit comparison of the results of different risk mitigation actions in terms of operational risk and safety. The principal advantage of this method is the high quality results obtained for a limited investment in terms of time, computing power and data. As such the method is extremely practical and easy to apply in aerodrome planning, development and operation.

Sensitivity Analysis of Engineered Material Arrestor Systems to Aircraft and Arrestor Material Characteristics

In most aircraft overruns, an aircraft comes to a stop within 1,000 ft (305 m) of the runway threshold. In response, U.S. airfields are required by FAA to have a 1,000-ft runway safety area in addition to the design runway length in case of aircraft overruns. At airfields where space is limited, airport operators need to consider alternative solutions. One solution is for an airport operator to reduce runway length and therefore limit aircraft types landing at their airport. Conversely a more attractive solution is for an airport to implement an engineered material arrestor system (EMAS). An EMAS is a passive system comprising a cementitious type material. Aircraft deceleration occurs because of drag forces that are incurred by the aircraft landing gear as the aircraft passes through and crushes the arrestor material. Parameters significantly influencing a B727 or B747 aircraft's stopping distance as it traverses an EMAS are presented. The computer code, ARRESTOR, developed for FAA, was used to compute the aircraft stopping distances. Five aircraft parameters (mass moment of inertia, weight, wheel friction, reverse thrust, and center of gravity location) for each aircraft type are examined, along with two arrestor material types (low-density concrete and phenolic foam) and three arrestor bed geometries. Each parameter is individually varied to investigate stopping distance sensitivity. Twenty-one overrun simulations were used in the aircraft parameter study, and 100 overrun simulations were used to determine an optimal material compressive strength. Arrestor bed geometry was investigated by using 32 overrun simulations. Study results are summarized in plots and tables.