NavList:

When I  use FlightRadar24 to observe aircraft flying over the Southern Ocean it seems that FR24 uses the mercator projection. This is not a problem because there are no (AFAIAA) commercial flighta over south pole. The highest I have seen a flight is at lat 75°. (Except for several military flights to bases in Antactica). However if I scroll up to the north pole I see several flights that might travel near (or over) the north pole. How does FR24 handle the crossing of the pole? Do the icons suddenly travel at warp speed while the ground speed remains at 500kt? I do not have the patience to sit and watch.

I know that I should be asking these questions of FR24 but I think that they are relevant for this thread so I will ask them here.

Does FR24 use mercator?

How does FR24 get aeroplanes over the north pole?

Does FR24 offer other projections?

What would a better projection be for FR24?

As a  plane approaches either pole do the icons increase in size (silly qustion I know but I can not help asking it)?

Is FR24/mercator responsible for  some people asking why aircraft do not take the shortest (i.e. straight) path between departure and destination.

When an aircraft is above about 75°  does FR24 switch to grid navigation? (which raises a very interesting question - what track does the aircraft report on ADSB when above lat 75°?)

In the meantine I will go back to studying the inverse Gudermannian function and trying to understand  the use of integral calculus in the Admiralty Manual of Navigation. It must be 50 years since I saw the integral symbol in the AMN. The Gudermannian function is something I have learned about more recently.

David C