> What I was trying to say was that governments have continued to invest millions of dollars in improving INS in the years since the AIRS was developed. The dri

> What I was trying to say was that governments have continued to invest millions of dollars in improving INS in the years since the AIRS was developed. The drift you need for days/weeks/months of navigation in a submarine is much much better than what you need for a few minutes of missile flights.