When would you use it in modern jet? Yes, I've flown trans-polar routes, use true north reference. I can guarantee it's never been in an FAA written or practical exam. Maybe when navigators roamed the cockpit with sextants and sharp, pointy objects, it was a test item for them.
EDIT: This thread sent me scurrying around the desk for an unused CR to work the problems. Dang, I didn't see the inner scale of 360 degrees. Off to Jepp website for the instructions--mine is a CR-2 and doesn't have that scale for grid nav problems that the CR-3 has. Having not used the CR-2 in 40 years, civil and military; 30 of them international I'm stunned at my ignorance.
Last edited by galaxy flyer; 27th Sep 2017 at 02:39.