We do have 'decels' here in Australia, they can be found in some of the most remote parts of the country. I have seen the result of a 'decel' rapidly losing speed after coming into contact with some of our native fauna. It has little, if any, effect on the height unless there is some associated tumbling after the contact. I think it's the pronunciation you are confused with, we usually pronounce it 'diesel' with the 'c' sounding more like a 'z'.
CH
