You are on a voyage from Nome to Honolulu via Unimak Pass (LAT 54° 30' N, LONG 164° 30' W). The great circle track passes through a point at LAT 38° 00' N, LONG 161° 40' W. Using gnomonic chart WOXZC 5270, determine which answer is TRUE. (The great circle distance, Unimak Pass to Honolulu, is 2013 miles.)
• Great circle vs rhumb line distance characteristics on long N–S vs E–W routes • Behavior and location of a great circle vertex relative to departure and arrival points • How distance is actually measured on a Mercator vs gnomonic chart
• Compare the approximate rhumb line course between Unimak Pass and Honolulu: is it mostly north-south or east-west, and what does that usually mean for distance savings with a great circle? • Think about where the highest latitude point (vertex) of a great circle between Alaska and Hawaii would fall: north or south of Unimak Pass and Nome? • Consider on which chart and by what method you actually measure great circle distance versus how you construct and then transfer the track.
• Verify where the vertex of the Nome–Honolulu great circle must lie in relation to both ports (north or south, and between which two points). • Confirm whether distance is ever measured directly as "1 degree of latitude = 60 miles" at a mid-latitude for a great circle track laid out on a gnomonic chart. • Check whether a rhumb line whose course is close to 180°/000° typically gains or loses much distance compared to the great circle.
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