Analiza sigurnosnih problema u zrakoplovstvu korištenjem TEM metode

This paper analyzes safety issues using Threat and Error Management (TEM) framework. Safety reports for the last decade were analyzed with special emphasis on year 2008. Causes of the accidents were determined and top three contributing factors were defined. Most common end states were identified and chains of events that led to them were analyzed. Furthermore, countermeasures were proposed in order to mitigate those safety concerns. Special care was taken to correctly identify those safety issues that stemmed from inefficient safety management systems, especially on the Operator\u27s level. Even though there is a general industry standard regarding safety management systems, it still has to be customized and optimized by each operator in order to gain the most out of it. Organizational procedures vary significantly from one operator to the other, reflecting size and structure of the monitored fleet, size of the operator and its engineering power. Therefore, it is often hard to adapt the safety management system to fit these organizational procedures. This inconsistency is a common contributing factor to aviation accidents.Ovaj rad analizira sigurnosne probleme korištenjem modela upravljanja ugrozama i greškama (TEM – Threat and Error Management). Analizirana su izvješća o nesrećama koje su se dogodile u proteklom desetljeću, s posebnim naglaskom na 2008. godinu. Utvrđeni su njihovi uzroci te tri faktora koja su najviše doprinijela njihovom događanju. Identificirana su najčešća krajnja stanja i lanci događaja koji su doveli do njih. Predložene su protumjere sa svrhom ublažavanja ovih sigurnosnih problema. Poseban je naglasak dan na pravilnu identifikaciju sigurnosnih problema koji su proistekli iz neučinkovitih sustava upravljanja sigurnošću, posebno gledano iz perspektive zrakoplovnih prijevoznika. Iako postoji općeniti industrijski standard primjene sustava upravljanja sigurnošću, on ipak mora biti prilagođen potrebama pojedinog prijevoznika, kako bi se osiguralo njegovo optimalno iskorištenje. Zbog razlika u veličini i strukturi flotâ prijevoznika, organizacijski postupci značajno se mijenjaju te je često teško prilagoditi sustav upravljanja sigurnošću tim organizacijskim postupcima. To je često faktor koji pridonosi nesreći

DETERMINING THE INFLUENCE OF OUTSIDE AIR TEMPERATURE ON AIRCRAFT AIRSPEED

Errors that occur in conventional measurement instruments connected to a pitot-static system affect the accuracy and reliability of indicating the basic navigation elements required for the safety of flight. This paper is to present the manner and methods of preparing and implementing experimental measurements in order to determine the stochastic and functional laws of deviation and change in the actual aircraft flying speed with the changes in altitude and airspeed, as well as to determine the influence of the change in air temperature on the measured values of airspeed up to the pressure altitude of 5,000 m. Using a comparative analysis of parameters measured during the flight by means of a sensor system on a twin-engine turboprop aircraft Antonov AN-32 and by means of a GPS instrument as well as theoretical calculations of pressure obtained in accordance with the measured values, this paper will present the problems of measuring the parameters by a pitot-static system

Development, Design and Flight Test Evaluation of Continuous Descent Approach Procedure in FIR Zagreb

As part of Local Conversion and Implementation Plan which is based on the EUROCONTROL Revised Convention the Republic of Croatia has undertaken to make a plan of implementing the Basic Continuous Descent Approach procedures. This paper addresses the issue of navigational path optimization for the A-319/320 commercial aircraft within the fleet of Croatia Airlines, during the approach part of flight, which has a positive effect on fuel consumption, greenhouse gas emission and area of surface affected by noise. The experiments were carried out in real conditions, using internal sensors onboard (Flight Data Recorder) and independent GPS system. Two types of approach were tested: Continuous Descent Approach (CDA) and Step Down Approach. The implementation of CDA procedures, just for the fleet of Airbus 320/319 aircraft of the Croatia Airlines results in approximate calculation in fuel saving which amounts to 1.5 x 106 kg annually (only on Zagreb airport). In this way, the productiveness of an air carrier, which is an integral part of the traffic process along with the airports and air traffic control, is directly increased, thus fulfilling the purpose of air traffic technology research. KEY WORDS: navigational procedures, continuous descent approach, air traffic, ecolog

Subjective Air Traffic Complexity Estimation Using Artificial Neural Networks

Air traffic complexity is usually defined as difficulty of monitoring and managing a specific air traffic situation. Since it is a psychological construct, best measure of complexity is that given by air traffic controllers. However, there is a need to make a method for complexity estimation which can be used without constant controller input. So far, mostly linear models were used. Here, the possibility of using artificial neural networks for complexity estimation is explored. Genetic algorithm has been used to search for the best artificial neural network configuration. The conclusion is that the artificial neural networks perform as well as linear models and that the remaining error in complexity estimation can only be explained as inter-rater or intra-rater unreliability. One advantage of artificial neural networks in comparison to linear models is that the data do not have to be filtered based on the concept of operations (conventional vs. trajectory-based).</p

Static Sensitivity of the Aerial Load Transport by Two Rotocopter Unmanned Aerial Vehicles

Aerial load transport by Unmanned Aerial Vehicles (UAVs) can be performed either using a single UAV or using a group of cooperative UAVs. The latter option is assumed more reliable, yet more demanding regarding the control and required power, than the former one. This article theoretically evaluates power consumption for aerial load transport by the use of two UAVs and compares it with the power consumption in case of a single UAV. In all treated cases, we assume a stationary level flight. For the stated comparison the theoretical model for aerial load transport by two identical UAVs is formulated. Generic flight characteristics and UAVs characteristics are prescribed, and corresponding solutions of the model evaluated. Independent parameters of the model are masses of the UAVs and the load, as well as flight velocity. Variables in the model are vertical and horizontal distances between the UAVs. The emphasis is put on the available instantaneous power and sensitivity to occasional wind gusts. We extract intervals of the model parameters for which each of the two UAVs is less loaded than a UAV which solitary carries a load. The sensitivity to wind gusts is lesser in configurations in which one UAV carries most of the load while the other provides the additionally needed instantaneous power

Free Route Airspace for Efficient Air Traffic Management

Free route airspace is a new concept in airspace management that has emerged from the Single European Sky ATM Research program. The goal is to allow aircraft companies to freely plan their routes between predefined points, rather than force them to follow conventional pre-established routes. This mode of airspace management can short-en trajectories, reducing fuel consumption and environmental impact. However, intersection points in a free route airspace are “invisible” at a strategic level, which can increase traffic complexity, increase the workload on air traffic controllers under certain conditions, and indirectly affect flight safety and efficiency of air traffic management. This review examines the implementation of free route airspace and its effects on air traffic management efficiency, leading to suggestions for future research

Free Route Airspace for Efficient Air Traffic Management

Free route airspace is a new concept in airspace management that has emerged from the Single European Sky ATM Research program. The goal is to allow aircraft companies to freely plan their routes between predefined points, rather than force them to follow conventional pre-established routes. This mode of airspace management can short-en trajectories, reducing fuel consumption and environmental impact. However, intersection points in a free route airspace are “invisible” at a strategic level, which can increase traffic complexity, increase the workload on air traffic controllers under certain conditions, and indirectly affect flight safety and efficiency of air traffic management. This review examines the implementation of free route airspace and its effects on air traffic management efficiency, leading to suggestions for future research

Methodology for Predicting Sector Capacity in Convective Weather Conditions

Convective weather conditions limit airspace capacity and increase the complexity of air traffic. Currently, air nav-igation service providers calculate sector capacity using air traffic controller workload as reference. The aim of the research is to propose a method for predicting sector capacity in convective weather using air traffic complexity model. In this proposal existing air traffic complexity model should be remodeled to enable finer resolution of com-plexity results. Also, the model should be upgraded with a new type of indicator showing aircraft-weather interactions. The adopted air traffic complexity model, in combination with the trajectory prediction model and the Weather En-semble Forecast, should be able to provide a statistical characterisation of sector capacity under impending convec-tive weather conditions

Determining Air Traffic Complexity – Challenges and Future Development

Air traffic complexity is one of the main drivers of the air traffic controllers’ workload. With the forecasted increase of air traffic, the impact of complexity on the controllers\u27 workload will be even more pronounced in the coming years. The existing models and methods for determining air traffic complexity have drawbacks and issues which are still an unsolved challenge. In this paper, an overview is given of the most relevant literature on air traffic complexity and improvements that can be done in this field. The existing issues have been tackled and new solutions have been given on how to improve the determination of air traffic complexity. A preliminary communication is given on the future development of a novel method for determining air traffic complexity with the aim of designing a new air traffic complexity model based on air traffic controller tasks. The novel method uses new solutions, such as air traffic controller tasks defined on pre-conflict resolution parameters, experiment design, static images of traffic situations and generic airspace to improve the existing air traffic complexity models.</p

Kastracija europskog smeđeg medvjeda.

Facilities for captive holding of European brown bears (Ursus arctos) are usually limited in capacity and already filled. The brown bear is a protected species, reduction of free-living population is not allowed and protection of existing numbers is requested by international conventions. The best regulation of population in captivity is by orchiectomy because of surgical simplicity and efficiency. We achieved general anaesthesia by use of a combination of ketamine hydrochloride and xylazine hydrochloride applied intramuscularly in four treated males. Surgical procedure of orchiectomy was carried out by closed method using two skin incisions parallel to raphe scroti in one bear and prescrotal incision in the remaining 3 bears. Spermatic cord was ligated by a triple clamp technique. Skin incisions were sutured by simple interrupted pattern with absorbable suture material. Recovery from general anaesthesia was without side-effects after a mean duration of 172 min. Mean surgery time was 54 min. The surgical wounds healed “per primam”.Ograđeni prostori i utočišta za zbrinjavanje europskih smeđih medvjeda (Ursus arctos) ograničeni su površinom za prihvat napuštenih jedinki. Budući da je smeđi medvjed zaštićena vrsta, valja voditi brigu o broju jedinki njihove populacije. Najbolja kontrola broja jedinki u zatočeništvu je putem kirurškoga zahvata kastracije odnosno orhiektomije mužjaka zbog relativno jednostavne izvedbe zahvata. Orhiektomija četiriju mužjaka obavljena je u općoj anesteziji kombinacijom ketamin i ksilazin hidroklorida primijenjenih intramuskularno. U sva četiri medvjeda orhiektomija je obavljena zatvorenom metodom. U jednoga je primijenjena metoda dva kožna reza usporedno s mošnjičnim šavom, a u tri medvjeda preskrotalna metoda orhiektomije. U svih je primijenjena tehnika tri hemostata prilikom podvezivanja sjemenova užeta, a rane su bile sašivene resorptivnim koncem pojedinačnim čvorastim šavom. Buđenje iz anestezije bilo je uobičajenoga tijeka bez nuspojava. Zahvat je prosječno trajao 54 minute, a opća anestezija 171,5 minuta. Sve kirurške rane zacijelile su „per primam”, a oporavak je prošao bez nuspojava