Jet goes down on its way to Medellin, Colombia

[A0283]

Just wondering ... maps ... again

In my post #974 my area of interest was on what ground you might expect between the VOR "RNG" and Cordova airport.

The next map in my stack was a Visual for Medellin airport. That showed more ground contour information. That map color-indicated the VOR plateau at 8,000ft without showing specific peaks/ridges.
Bit of a surprise then when taking the AIP Colombia next which gives the DVOR "RNG" an elevación of 8,669 ft.

No problem at all if you are following MSA guidance, but can give you a nasty surprise if you do not take a detailed look at the available information in an emergency descent.


When you go to the AIP SKRG Visuals you find values of peaks/ridges around the VOR of between 8,450-8,900 ft.

I dont know the altitude of the initial impact ridge. A rough estimate is that it is at the VOR altitude level plus/minus a few hundred feet.

Gives a bit of a 'Guam' feeling.

It suggests that the "map resolution"/"cut-off" criterium for VFR is indeed different from that of IFR and neither shows consistency in application.

Best advice with these maps appears to be to ignore all specific peak/ridge information and just add 1,000ft to all contour information. Which means in this case that the plane should have stayed above 9,000 ft over the VOR.