Complex sentence: Trained as a fighter pilot, between 1925 and 1928 he served in Hawaii-there he wrote a guidebook to the islands "When you go to Hawaii you will need this guide to the Islands", which was published in 1930.
Split into simpler sentences: Trained as a fighter pilot, between 1925 and 1928 he served in Hawaii. While there he wrote a guidebook to the islands "When you go to Hawaii you will need this guide to the Islands", which was published in 1930.