eng Science and Education Publishing American Journal of Mechanical Engineering 2014-11-05 2 7 252 257 10.12691/ajme-2-7-16 AJME20142716 article Marian Dudziak 1 Andrzej Lewandowski 2 Michał Śledziński michal.sledzinski@put.poznan.pl 2 Poznan University of Technology, Chair of Basics of Machine Design, 60-365 Poznań, ul. Piotrowo 3, Poland Jan Sehn Institute of Forensic Research in Kraków, 31-033 Kraków, ul. Westerplatte 9, Poland The authors describe a road traffic accident with an unusual cause which was a wrong defensive reaction of the driver on the road surface covered with spilled grain. The results of road tests are presented illustrating behaviour of the vehicle on the road surface in such conditions. Attention is paid to the psychological aspect of the drivers defensive reactions in the situation when they are taken aback with non-typical road surface conditions. There is a need to train drivers in right decision making skills (psychology) and in the ability to make effective defensive manoeuvres (driving technique) in order to improve road traffic safety. http://pubs.sciepub.com/ajme/2/7/16/ajme-2-7-16.pdf road accident causes driving psychology road tests