NavList:

Dave wrote:

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I thought it wise to check on this before someone else did, and here it is.  http://webarchive.nationalarchives.gov.uk/+/http://www.aidu.mod.uk/enroute.html This document states that most RAF en-route charts were, at the time of the archive, Oblique Mercator projections.  They probably still are.  If you follow the link, you’ll see the meridians and parallels don’t go straight up and down and across the cut of the chart, but they do cross at right angles, so the chart is still conformal.  DaveP

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In the U.S., since 1929, almost all aeronautical charts use the Lambert conformal projections. Only those charts withing ten degrees of the poles use the Polar Sterographic projection.

This includes:

Terminal area charts (TAC, 250,000 to 1)

Sectional charts (500,000 to1) 

World Aeronautical Charts (WAC, 1,000,000 to 1)

Tactical Pilotage Charts (TPC, 250,000 to 1)

Operational Navigation Charts (ONC, 1,000,000 to 1)

Jet Navigation Charts (JNC, 2,000,000 to 1)

Global Navigation charts (GNC, 5,000,000 to 1)

Low altitude enroute charts

High altitude enroute charts

Instrument approach charts

Aircraft Position charts

and "Jepps"

I did find this notation on Pacific Enroute Chart 12 near New Zealand, "ALL COURSES TO ANTARCTICA SOUTH OF CHRISTCHURCH ARE DERIVED FROM TRANSVERSE MERCATOR PROJECTIONS."

gl