Navigation over the Pacific

[Windturbin]

Cheers,

Am building missions/campaign over the open pacific. Would like to learn how pilots navigated over the open pacific waters without landmarks and how that relates to the IL-2 in game map. Without using path and icon cheats.

Using Wake Island as an example: The in game map graph has letters and numbers, Wake Island is @ Bm and 42, would these be called sectors? The map also has what looks to me likes longitude and latitudes numbers , Wake Island is @ 220 and 389? Problem is Wake Island is actually Longitude 166.6177 and Latitude 19.2900. What gives?

How did WWII Pilots navigate in the pacific? Anyone know of any good links for study? Can real life 1940's navigation be duplicated in game? Can anyone tell me the basics of how they did it?