Sir Francis Chichester flew a Tiger Moth floatplane across the Tasman Sea and had to find the small islands of Lord Howe and Norfolk Island which were refuel stops in the middle of the Sea. All he had was a Compass and a Sextant, charts etc
Instead of planning to route direct he deliberately planned to go about 60 miles abeam the island(s) and after flying for circa 2/3 hours he then knew for sure that the island was on the right hand side of the a/c. He then turned right through ninety degrees and flew along a position line off the sun to find the island. A brilliant bit of navigation!
Ok we're not flying across oceans finding small islands but there is much to be learned from what he did.
He wrote a book (amongst many) called "Alone Over the Tasman Sea" which if you can get a copy is an excellent read.
Oh and he did this in 1929.
Sir Francis Chichester