Abstract: There are offered many ways how to improve work of a spark plug.But one of the m ost important problems has not been solved yet.This is a thermal mode operation of a spark plug.The ideal spark plug should be instantly heated at the moment of occurrence of a spark and instantly cooled down in expectation of the foll owing electrical pulse.Thus it balances between preservation of heat for selfc leaning from scale and its removal in avoidance selfignition.In this article a uthor managed for this time to offer a spark plug with capability “selfregula tion” of heat flux removed from a zone of ignition.Essence of the offer is a t ip，which is transparent for heat flux.It is produced from single crystal of sap phire.

Key words: There are offered many ways how to improve work of a spark plug.But one of the m ost important problems has not been solved yet.This is a thermal mode operation of a spark plug.The ideal spark plug should be instantly heated at the moment of occurrence of a spark and instantly cooled down in expectation of the foll owing electrical pulse.Thus it balances between preservation of heat for selfc leaning from scale and its removal in avoidance selfignition.In this article a uthor managed for this time to offer a spark plug with capability “selfregula tion” of heat flux removed from a zone of ignition.Essence of the offer is a t ip，which is transparent for heat flux.It is produced from single crystal of sap phire.