A solution for crash and high ground unevenness effect reducing

On landing operation, a brutal contact with the deck or ground, or high ground unevenness 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 dimension, the VZN concept confers possibilities to assure constant deceleration forces, at the human body limit resistance, this solution dissipating the maximal energy quantity. The paper evaluates by simulation, the behaviour at vertical crash of aerial vehicles equipped with suspension using VZN and standard dampers. The results given by VZN concept is 200% better than the standard dampers, this new solution giving high possibilities to reduces the risk at landing, a better passengers and body protection, without increased costs. The VZN principle, and damping coefficients, comparative with standard and monroe sensa trac, the kinematic model, speed - time and acceleration evolution for VZN and standard dampers, detail for acceleration - time evolution at VZN and standard dampers acceleration - time evolution for VZN and standard dampers are presented in the paper.