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1
Content available remote Crashworthiness of a type 228M rail vehicle
Witkowski Dawid, Tarnawski Piotr, Stefańska Natalia
Pojazdy Szynowe
|
2022
|
Nr 3-4
37--43
EN
This article presents crashworthiness issues based on the design of the 228M type light rail vehicle. Meeting the requirements of the standard requires the use of appropriate components dedicated to energy absorption and ensuring adequate strength of the body. After analyzing the scenarios, it can be concluded whether type light rail vehicle. 228M meets the normative requirements for crashworthiness.
2
Content available Precrash vehicle velocity determination using inverse system and tensor product of Legendre polynomials - subcompact car class
Gosławski Łukasz, Madziara Szymon, Droś Bartosz, Knap Lech, Ma Yanlin, Mrowicki Adam
Archiwum Motoryzacji
|
2022
|
Vol. 97, nr 3
14--24
EN
Presented paper discusses new approach to EES parameter determination in frontal car crash based on the tensor product of Legendre polynomials. In this paper Subcompact Car Class was analyzed using that method. Data that was used to perform analyses introduced in this paper was taken from National Highway Traffic Safety Administration (NHTSA) database. Such database consists of considerate number of test cases along with various information including vehicle mass, crash velocity, chassis deformation etc. New approach to the problem of determining the EES parameter was necessary due to the low accuracy of the currently used methods. Linear models used up till now for accident reconstruction show significant error as the relationship between mass, velocity and deformation cannot be well approximated with a flat plane. Proposed model produces better results, because of the nonlinear dependence of said parameters. This paper also includes a calculation example presenting a comparison of linear and nonlinear method on an actual crash test.
3
Content available Analysis of safety impact of paved shoulder width on Czech secondary roads
Ambros Jiří, Křivánková Zuzana, Zůvala Robert, Bucsuházy Kateřina, Frič Jindřich
Archives of Transport
|
2021
|
Vol. 60, iss. 4
125--136
EN
Traffic safety is influenced, among other factors, by characteristics of the roads, which include the width of the shoulder. Shoulder width was noted to have a large effect on crash frequency, as well as on traffic speed. In this paper, we focused on paved shoulders. Previous studies confirmed that increasing the width of the paved shoulder is associated with a decrease in crash frequency. However, wider shoulders may encourage higher driving speed, which is related to an increase of impact speed and crash severity – this issue was hypothesized, but not statistically investigated. Thus, conclusions based on crashes and speeds contradict each other, and there is no simple answer to the question of the safety impact of wide shoulders. To address this gap, we analyzed a sample of two most typical categories of Czech secondary roads, which differ only in the paved shoulder width (S9.5 roads with 0.75m-wide shoulder, and S11.5 roads with 1.75m-wide shoulder) and thus present a suitable example for studying the safety impact of paved shoulder width. We used generalized linear models of crash frequency, and multinomial logistic models of crash severity (separately for single-vehicle and multi-vehicle crashes), as well as a statistical test of differences in speed for the two road categories. The results showed that: Firstly, there were fewer crashes on S11.5 roads compared to S9.5 roads; this was true for both single-vehicle and multi-vehicle crashes. Secondly, single-vehicle crashes on S11.5 roads were more severe compared to S9.5 roads; the change of severity in multi-vehicle crashes was not statistically significant. Thirdly, driving speeds on S11.5 roads were approx. by 7 km/h higher compared to S9.5 roads. These findings support the hypothesis of an association between wider shoulders, higher speeds, and increased crash severity, especially in the case of single-vehicle crashes. As a practical solution, various speed management measures, including widening to a 2+1 road, may be recommended.
4
Content available Irregular operation of autonomous vehicles
Vida G., Váradi P.
Production Engineering Archives
|
2018
|
Vol. 20
8--11
EN
Today, with the spread of autonomous functions in vehicles, the role accountability for causing accidents is emphasized. Self-guided functions work in certain traffic situations, but accidents happen, and, therefore, the following article presents an analysis of the issue. Its purpose is to show that vehicles with self-drive functionality do not provide the driver's level of safety that vehicle manufacturers suggest. In this article, four recent events and an analysis whether these accidents could have been avoided a human driver or how they could have happened with appropriate self-drive function. In each of the investigated cases, vehicles equipped with self-drive function are involved. Based on the evaluation and assessment of accidents, conclusions are drawn whether current self-propelled vehicles provide the safety level that drivers and society expect from these vehicles. The reconstruction of the accident process is illustrated with the help of a vehicle simulation program, with the resultant parameters being given a special emphasis, in particular to the avoidance of the accident.
5
Content available Material definition to design vehicle components, application to crashworthiness
Rusinek A., Zaera R.
Logistics and Transport
|
2018
|
Vol. 38, No. 2
63--67
EN
In this paper a short description is reported allowing to take into account some aspects to design structures used for automotive industries. It allows to define correctly the behaviour of a vehicle and mainly the passive structures to absorb energy during an accident or an impact. The main aspect related to the behaviour is the strain rate sensitivity coupled to the process of elastic wave propagation.
6
Content available Testy zderzeniowe kasety ochronnej systemu rejestracji parametrów lotu S2-3a
Jakielaszek Z., Panas A. J., Nowakowski M., Kowaleczko G.
Autobusy : technika, eksploatacja, systemy transportowe
|
2017
|
R. 18, nr 12
165--177, CD
PL
W artykule został opisany etapowy przebieg badań zjawiska zderzenia z przeszkodą sondy pomiarowej imitującej kasetę ochronną systemu rejestracji parametrów lotu S2-3a. Celem badań było uzyskanie wymaganego impulsu trapezoidalnego przeciążenia, o wartości 3400 g, działającego na kasetę przez co najmniej 3 ms dla ustalenia zgodności z normą NO-16-A200:2006 oraz EuroCAE ED-112.
EN
In the paper methodology of a crash test execution is described. The procedure was developed in a course of repeated experimental probe impact tests with changed configurations and parameters. The probe contained imitator of a crash flight data recorder S2-3a. The purpose of the studies was to obtain an test impulse envelope of trapezoidal shape of the amplitude 3400 g for et least 3 ms that comply with standards NO-16-A200:2006 and EuroCAE ED-112.
7
Content available Doświadczalne określenie parametrów testu zderzeniowego rejestratora katastroficznego
Jakielaszek Z., Białecki M., Bryl M., Panas A. J., Nowakowski M.
Autobusy : technika, eksploatacja, systemy transportowe
|
2017
|
R. 18, nr 6
223--229, CD
PL
W artykule omówiony został proces określenia parametrów charakteryzujących zderzenie rejestratora katastroficznego z przeszkodą w celu ustalenia zgodności z normą NO-16-A200:2006 i ED-112. Ocenie podlega odporność rejestratora katastroficznego na przeciążenie o wartości 3400 g. Badania zrealizowano z wykorzystaniem działa pneumatycznego DPZ-250.
EN
The problem of crash tests for the black box data recorder has been discussed. By performing a sequence of experimental studies parameters of a test have been adjusted and optimized. The test meets requirements of the norm NO-16- A200:2006 and ED-112. The studies were carried out using pneumatic canon DPZ-250. The tests proved resistance of the investigated data recorder to the average overload of 3400g for 3ms.
8
Content available Crash safety of a typical bay table in a railway vehicle
Matsika E., Peng Q.
Transport Problems
|
2015
|
T. 10, z. spec.
97--110
EN
Increasingly, urban and high speed trains are incorporating tables (workstations) as common railway vehicle interior furniture because passengers prefer seating by bay tables. Among table design characteristics, the most challenging is meeting crashworthiness requirements. Past accident data and sled test results have shown that in the event of railway vehicle frontal impact, occupants located in the bay seating are exposed to chest and abdominal injuries upon contact with tables resulting from secondary collision. In some cases tables have tended to be structurally weak; they easily detach from the side walls and/or floor mounting. Subsequently these become unguided missiles that strike occupants, resulting in injuries. This paper presents an analysis of the crash performance of a typical bay table. The results provide some understanding of the table’s crash safety, giving an indication of its impact aggression. Table materials are characterised using quasi-static compressive tests. In addition, experimental dynamic (impact) tests are conducted using a pendulum representing a body block (mass). The results provide information about the possible loading of the table on the occupant in the event of a crash. Contact forces are compared with chest and abdominal injury tolerance thresholds to infer the collision injury potential. Recommendations are then made on design of bay tables to meet the “functional-strength-and-safety balance”.
PL
Coraz częściej zarówno w pociągach miejskich, jak i pociągach dużych prędkości wprowadza się do wyposażenia stoły. Wynika to z wymagań pasażerów, którzy to preferują siedzenie przy stołach. Wśród cech konstrukcyjnych stołów, największym wyzwaniem jest spełnienie wymagań wytrzymałości zderzeniowej. Wcześniejsze informacje dotyczące wypadków i wyniki badań wykazały, że w przypadku czołowego zderzenia pojazdów kolejowych pasażerowie, znajdujący się w sąsiedztwie stołów, są narażeni na urazy klatki piersiowej i brzucha na skutek wtórnej kolizji. W niektórych przypadkach stoły miały słabą strukturę; w prosty sposób można je było odłączyć od ścian bocznych i/lub podłogi, do których były przymocowane. W następstwie stawały się one niekontrolowanymi pociskami, które uderzały pasażerów i powodowały ich obrażenia. W artykule przedstawiono analizę wyników wypadku dla typowego stołu. Wyniki dostarczają wiedzę o bezpieczeństwie w razie zaistnienia 98 E. Matsika, Q. Peng wypadku z udziałem stołu, podają informacje o skutkach. Materiały stosowane na stoły zostały zbadane za pomocą quasi-statycznych testów ściskających. Ponadto, przeprowadzono eksperymentalne dynamiczne testy wykorzystujące wahadło. Wyniki dostarczają informacji na temat potencjalnego oddziaływania stołu na pasażera w momencie zderzenia. Siły kontaktowe są porównywalne z progami tolerancji, odpowiadającym klatce piersiowej i jamie brzusznej, w wyniku czego można przewidzieć skutki kolizji. W związku z tym zaleca się wykonanie stołów z zachowaniem „równowagi funkcjonalności, wytrzymałości i bezpieczeństwa”.
9
Content available remote Kompozyty polimerowe jako osłony cieplne rejestratorów lotniczych
Kucharczyk W., Przybyłek P., Opara T. A.
Przetwórstwo Tworzyw
|
2013
|
[R.] 19, nr 4 (154)
365--369
PL
W artykule przedstawiono wymagania dotyczące zdolności rejestratorów lotniczych do przetrwania katastrofy lotniczej określone w kolejnych dokumentach normatywnych. Zaprezentowano możliwość zastosowania kompozytowych materiałów ablacyjnych na kapsuły ochronne o wyższych, cieplnych parametrach użytkowych. Zamieszczono wyniki badań ablacyjnych właściwości termoochronnych kompozytów epoksydowych z hybrydowym wzmocnieniem włóknistym i glino-krzemianami warstwowymi. Opisano jakościowy i ilościowy wpływ zmiennych fazowych składów kompozytów na badane właściwości ablacyjne: temperaturę tylnej powierzchni ścianki próbki izolującej ts, średnią szybkość ablacji va, oraz ablacyjny ubytek masy Ua.
EN
At the paper briefs assumptions and requirements on an experimental research how to create Flight Data Recorders (FDR)’ protective case covered ablative composite. The paper reports results of studies on ablative and thermal properties of epoxy composites with hybrid fabrics-reinforcement (kevlar and carbon fibers) filed with a mixture of epoxy resin and mineral nanoclays (layered silicates). Quantitative and qualitative influences of phase type-matter on ablative properties were presented. The composites were treated with hot combustion gases to detect the temperature profiles across the studied samples (cubes 10 x 25 x 35 mm), the average linear rate of ablation va, and their mass waste Ua during ablation processes.
10
Content available remote A General Model to Monitor the Risk of a Failure to a Means of Transport in Service
Tomaszek H., Kaleta R., Zieja M.
Prace Naukowe Instytutu Technicznego Wojsk Lotniczych
|
2013
|
nr 33
19--32
EN
A model to monitor the risk of a failure/damage (undesirable event) to a means of transport has been outlined in the paper, with findings presented in [2] applied. Destructive processes such as the wear-and-tear, fatigue, and ageing, which arise in the course of the system’s (here: the means of transport) service are most fundamental factors that make health/maintenance status thereof deteriorate. A relationship that describes the probability of an undesirable event (failure) against the system’s service life has been formulated. The rate at which undesirable events may occur, i.e. the failure rate, has also been defined. What results from derived relationships is the statement that failure rates are functions of time the system remains in service. With the permissible risk level assumed, there is a chance to determine the permissible time of failsafe operation.
11
Content available Bezpieczeństwo transportu
Bril J., Łukasik Z.
Autobusy : technika, eksploatacja, systemy transportowe
|
2013
|
R. 14, nr 3
1895-1905
PL
W artykule ukazana została próba przybliżenia bezpieczeństwa transportu, główne przyczyny powstawania wypadków oraz stan bezpieczeństwa w poszczególnych gałęziach transportu wraz z ich przyczynami i głównymi sytuacjami inicjującymi powstanie zdarzenia.
EN
In article an attempt has been depicted to approximate of transport safety, the main causes of accidents and the security situation in the various transport sectors, including their causes and the main situations initiating the formation of road events.
12
Content available remote Damage analysis of composites integrated with RFID chip used in aeronautics
Alhas H-A., Bayraktar E., Nizam C., Khalil J.
Archives of Materials Science and Engineering
|
2013
|
Vol. 59, nr 1
5--13
EN
Purpose: A new approach to production process by direct integration of the RFID (Radio-frequency identification) chips into the composite parts used during the manufacturing (moulding) process of the composite parts has been presented. This research aims a new application of RFID technology and measurement of the resistance of RFID chips integrated into composite parts under X-ray diffraction beams and also impact choc (crash test). This work gives the actual results of an applied research carried out in laboratory (Supmeca-Paris) scale and also in industrial scales carried out in the manufacturing department of the French aeronautic company (Eurocopter-Paris). Design/methodology/approach: Application of RFID technology in manufacturing of the composite parts is related to the continuous quality improvement of manufacturing company. Findings: RFID Chips integrated directly in the composite parts during the manufacturing process can improve the efficiency of the manufacturing process and also decrease the lead time and processing time. This application in manufacturing of the composite parts will enable to achieve success for the aeronautic companies. Research limitations/implications: In the future, Industrial companies can transform their manufacturing processes by applying RFID technology that increases manufacturing cycle time, maximize efficiency and eliminate unnecessary steps. Practical implications: Using RFID technology in production will help industrial companies and also customers reduce their time and operating costs significantly and increase employee productivity. This application can also decrease lead time and make faster progress toward their sustainability goals. Originality/value: A detail comparison was made between two approaches; conventional production system and new approach by integrating RFID in composite part. At the end of analysis, time saving in the production was calculated as 135 minutes (more than 2 hours) by following real data.
13
Content available remote Numerical modelling and simulation of road crash tests with the use of advanced CAD/CAE systems
Niezgoda T., Barnat W., Dziewulski P., Kiczko A.
Journal of KONBiN
|
2012
|
No. 3 (23)
95--108
EN
The paper presents the methodology of numerical modelling of road crash tests based on the selected vehicle-road barrier system using the possibilities of modern CAD /CAE computing systems for a numerical simulation process of the collision. Owing to these systems, thorough analysis of the process of collision, including the analysis of the stress and strain fields and energy consumption in the tested systems, is possible. It is possible to design and redesign virtually the barriers at a relatively low cost.
PL
W artykule przedstawiono metodykę modelowania numerycznego drogowych testów zderzeniowych na przykładzie wybranego układu pojazd-drogowa bariera ochronna, z wykorzystaniem możliwości nowoczesnych systemów obliczeniowych CAD/CAE do numerycznej symulacji przebiegu zderzeń. Dzięki wykorzystaniu tych systemów możliwa jest dogłębna analiza procesu zderzenia, w tym analiza pól naprężeń, odkształceń oraz energochłonności badanych układów. Możliwe jest wirtualne projektowanie i przeprojektowywanie barier przy relatywnie niskich kosztach.
14
Content available Finite element method in car compatibility phenomena
Lisiecki M.
Journal of KONES
|
2011
|
Vol. 18, No. 4
234-241
EN
The main aim of the study is the side impact of the truck into the passenger car, which is one of the possible variants in compatibility case. The compatibility problem has direct influence at biomechanical injuries of the passengers travelling by the cars and also at deformation of the structure. This research should assign critical configurations of the truck and the car during side impact. Critical criteria of compatibility problem are biomechanical injuries structure deformation. The research was performed with Chrysler Neon mode, automotive seating (metal construction), Hybrid III dummy model and moving barrier with changed mass (equals to the mass of the heavy truck KAMAZ) and equipped with front under run protection barrier (FUP - based on the geometry of the Mercedes ACTROS'front structure). Interaction between car and heavy truck is at the driver side. During the research different location and angles of the barrier against the car has been taken into account. Two speeds were used to investigate the barrier influence to the car. The results of the simulation allow predicting the biomechanical coefficients such as: HIC, 3ms, TTI, e.g., which give the overview of the passenger injuries. The other set of the data is plastic deformations which are visible at the Front Underrun Protection (FUP) barrier and also at the passenger car construction. The results of research allows to assign the direction of the changes which should be proposed to the truck manufactures in order to reduce passengers biomechanical injuries and intrusion into car during side impact.
15
Content available Tragedia smoleńska na tle rozrachunków z przeszłością
Ciećkowski Zbigniew A.
Wiedza Obronna
|
2010
|
nr 2
127--134
16
Content available On „VZN" damper behaviour at crash
Niculescu A. -I., Jankowski A., Gardulski J.
Journal of KONES
|
2010
|
Vol. 17, No. 3
321-326
EN
Passive security at crash is an importami problem both for road, and aerial vehicles, first case at horizontal collision and second at vertical one, on landing operation on ground or deck. Both generate human and material injuries, many of them with important negative effects. Damper in bumper a known solution for vehicles protection at crash is realized with different damping devices, from passive elements to actuators. Usually the devices are tuned for 5 km/h crash speed and after collision the passive solutions destroy and must be replaced with other new devices. The solutions using standard shock absorbers and actuators are improper the first dissipating insufficient energy and actuators being more expensive and having a long reaction time so the damping coefficient changing is realized in too low steps. VZN damper concept granted with European Patent EP l 190 184 and Romanian Patent RO l 18546, characterized by progressive damping coefficients with the stroke assures protection at crash, due to its capacity to realize constant damping force without mechanisms and electronics, tuning damping characteristic to this desiderate. The paper presents the differences between the energy must to be dissipated at the same crash speed in horizontal and vertical situation, it being increased at vertical situation, due to the gravity. The same paper evaluates the advantages confers by VZN damper concept comparative to standard one, for both vertical and horizontal collision and concludes the VZN one is better 39% at vertical crash and 25% at horizontal crash comparative to standard one, due to its efficient dissipating system.
17
Content available Finite element method in car compatibility phenomena
Lisiecki M.
Journal of KONES
|
2010
|
Vol. 17, No. 1
241-247
EN
The main aim of the study is the side impact of the truck into the passenger car, which is one of the possible variants in compatibility case. The compatibility problem has direct influence at biomechanical injuries of the passengers travelling by the cars and also at deformation of the structure. This research should assign critical configurations of the truck and the car during side impact. Critical criteria of compatibility problem are biomechanical injuries structure deformation. The research was performed with Chrysler Neon mode, automotive seating (metal construction), Hybrid III dummy model and moving barrier with changed mass (equals to the mass of the heavy truck KAMAZ) and equipped with front underrun protection barrier (FUP - based on the geometry of the Mercedes ACTROS front structure). Interaction between car and heavy truck is at the driver side. During the research different location and angles of the barrier against the car has been taken into account. Two speeds were used to investigate the barrier influence to the car. The results of the simulation allow predicting the biomechanical coefficients such as: HIC, 3 ms, TTI, e.g., which give the overview of the passenger injuries. The other set of the data is plastic deformations which are visible at the Front Underrun Protection (FUP) barrier and also at the passenger car construction. The results of research allows to assign the direction ofthe changes which should be proposed to the truck manufactures in order to reduce passengers biomechanical injuries and intrusion into car during side impact.
18
Content available  Novel damper for passive security increasing
Niculescu A. I., Jankowski A.
Journal of KONES
|
2010
|
Vol. 17, No. 1
299-308
EN
Horizontal crash at road and rail vehicles generates human and material injuries, many of them with important negative effects. Damper in bumper a known solution for vehicles protection at crash is realized with different damping devices, from passive elements to actuators. Usually the devices are tunedfor 5 km/h crash speed. After collision the passive solutions destroy and must be removed with other new devices. The solutions using standard shock absorbers and actuators are improper the first dissipating insufficient energy and actuators being more expensive and having a long reaction time so the damping coefficient changing is realized in too low steps. VZN damper concept granted with European Patent EP l 190 184 and Romanian Patent RO l 18546, characterized by progressive damping coefficients with the stroke is a great opportunity to realize simple and cheap protection at crash, due to its capacity to realize constant damping force without mechanisms and electronics. li is necessary only to tune accordingly VZN damping characteristic to this desiderate. VZN concept consist of u piston rod attached to a piston without valves moving inside inner cylinder close at both ends and filled at rebound and compression by specific fllling valves placed in upper /bottom lids or on the ends of the inner cylinder. The damping effect is realized by valves or in cheap solution by metering orifices (holes/slots) placed sideways inner cylinder in convenient position. Due to this structure VZN tuning for constant damping force at different piston speed can be realize both with identical metering holes/slots placed at optimal distances, or placing metering holes/slots of different areas at eąual distances. The numbers of metering holes/slots are enough such the steps speed evolution be practical continuous and thus the damping force be practical constant. The VZN behaviour is increased by new components e.g. levelling pistons, double guiding elements and balancing solutions. Paper presents the theory used to dimension VZN damper placing metering orifices at eąual distances, a practical device with levelling piston and simulation comparative to standard one. The standard damper dissipates 30-40% lower energy comparative to VZN one. This means in the same situation in which VZN damper reduces constant speed from 30, respectively 20 [km/h] to zero, the standard dampers reduces speed up to 14, respectively 11 [km/h], then collapsing the vehicle.
19
Badania metaloznawcze łożysk silników samolotu PLL LOT IŁ-62M „Kościuszko”, który uległ katastrofie w Lesie Kabackim 9 maja 1987 r.
Przygodzka H.
Inżynieria Powierzchni
|
2010
|
Nr 3
62-73
PL
Badania metaloznawcze dla wyjaśnienia przyczyn katastrofy samolotu pasażerskiego PLL LOT IŁ-62M „Kościuszko” w dniu 9 maja 1987 r. w Lesie Kabackim, wynikały z niezgodności opinii ekspertów producenta łożysk i ekspertów polskich, prowadzących wspólnie wstępne badania w IMP. Kontrowersje te dotyczyły łożysk tocznych sprężarki i turbiny silników samolotu IŁ-62M „Kościuszko”. Łożyska te stanowiące węzeł konstrukcyjny każdego z czterech silników mogły być elementami, które zainicjowały katastrofę samolotu. Pierwszym bardzo ważnym wynikiem ekspertyzy było wykazanie, że łożysko jednego z silników uległo zniszczeniu przez zatarcie. Istotną przyczyną zniszczenia łożyska było usunięcie przez producenta połowy rolek w celu obniżenia masy łożysk. Spowodowało to nadmierne obciążenie stykowe pozostałych rolek. Czynnikiem sprzyjającym zmęczeniu i zatarciu jednego z nich była zbyt niska jakość materiału łożysk, ułatwiająca wykruszanie się twardych węglików i cząstek materiału zwiększających intensywność zużycia ściernego. Badania łożysk obejmowały obserwację mikrostruktury przy użyciu mikroskopu świetlnego „Neophot” i skaningowego mikroskopu elektronowego JSM-50A oraz pomiary twardości metodą Vickersa.
EN
Physical metallurgy research was done to clear up differences in experts opinios on the reason of PLL LOT IŁ-62M „Kościuszko” aircraft crash in 9 of May 1987 in Kabaty Forest. There were controversies between producer experts and polish experts about rolling bearing of the compressor and the turbine of IŁ-62M “Kościuszko” aircraft. It was stated that catastrophe (failure) was initiated because the bearing in one of the engines was destroyed as the consequence of a seizure inside it. Producer had reduced to the half the number of the rolls inside the bearing to make it lighter. Also low quality of bearing material was caused by hard carbides and other particles which had been broken out from the surface and facilitate fatigue failure and a seizure. Microstructure of the bearing metal was done by “Neophot” light microscopy, and JSM-50A scanning electron microscopy and also Vickers hardness measurements were done.
20
Content available On „VZN" damper behaviour at crash
Niculescu A. I., Jankowski A., Sireteanu T.
Journal of KONES
|
2009
|
Vol. 16, No. 2
369-374
EN
On landing operation, a brutal contact with the dech or ground, can damage the plane or chopper and hurt the pilot, the crew or the passengers. The paper presents the advantages confer by suspensions using VZN dampers, in this situation. The Romanian self adjustable damper (shock-absorber) concept- VZN-granted with European Patent EU 1190184 and Romanian Patent 118546 assures damping coefficients increasingly by stroke from lower value up to the very high values, giving thus possibility to dissipate a huge energy at all speed regimes high, medium or low. With a convenient damping valve placement and/or dimension, the VZN concept confers possibilities to assure constant decelerationforces, at the human body limit resistance, this solution dissipating the maximal energy ąuantity. The paper indicates solutions for VZN tuning in order to be used to realize constant deceleration at crash and developed one of them for a practical device realizes. The samples where developed so to be realized with components used in actual automotive shock absorber manufacturing, so prototypes being easy to realize. Despite the simulations was realized considering standard damper dissipating energy function piston speed, not sąuare piston speed, the standard damper dissipated 48.5% lower energy comparative to VZN one. This means in the same situation in which VZN damper reduces constant speed from 20 [km/h] to zero, the standard dampers reduces speed up to 11.5[km/h], then collapsing the aerial vehicle.
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