Offsetting track to destination
PhiggsBroadband, above, refers to offsetting and its use in orienteering navigation.
Sir Francis Chichester was the first to use it effectively in flying. He was born in the UK, emmigrated to New Zealand at the age of 18. In 1929 he bought a Gipsy Month aircraft in the UK, and flew it solo to Oz. From there, because it could not carry enough fuel to cross the Tasman sea, he shipped it to NZ, and fitted it with floats (which he did not always remember to pump dry before flying!).
He was the FIRST to use off course navigation in flying, steering to one side so you know which way the error is. In this way he was able to find tiny islands in the Pacific ocean.
After WWII he set up a map making company in the UK. And when diagnosed with cancer, retired, and sailed around the world in Gipsy Moth, the sailboat now restored and used for training young people.