My dad was stationed on a submarine in the navy and he and a few others used to dump their laundry in the ultra-sonic cleaner normally used to clean engine parts. Said it did a great job....
When the choice is between the smell of unwashed and sweaty sailors with dirty clothes, or smoke, ashes, fag-ends and tobacco, then surely the latter beats the former.
The biggest downside: rinsing. You have to do it manually. And no, just refreshing the water and letting the ultrasonic emitter run will do nothing. And doing it manually takes a surprising amount of time.