frank owen is from the submarine institute of australia and joins us now from canberra. ybody new, saw its _ we have? we know that the last time anybody new, saw its always - we have? we know that the last time anybody new, saw its always aware i we have? we know that the last time | anybody new, saw its always aware of its position was at 4:28 on tuesday. the next time there was any evidence of its existence, if that evidence, is that they saw an oil slick that may or may not have come from the submarine. there has been nothing heard of it since stop frank, some people, you can expand first, they say submarines to go silent for periods of time for operational reasons, is there not something on the submarine, some piece of technology that would always alert somebody somewhere as to where it was? ., , ., ., ., was? how is it that we would not know anything? _ was? how is it that we would not know anything? yes, _ was? how is it that we would not know anything? yes, you i was? how is it that we would not know anything? yes, you are i was? how is it that we would not i know