Microsoft Virtual Earth Goofiness

Jay, a friend at work (known as JBall to most of those who work with him), is a private pilot and owns a Cessna 182 Skylane.

As such Jay does a fair amount of reading online about aviation issues and topics.  He also plays around with Microsoft Virtual Earth.

I’m not sure how he found this, but he showed this to me last week, and I told him I thought it was notable enough to post here so others could see it too.  So I’m stealing this discovery from Jay and posting it here.  (Thanks, Jay!)

Telluride, Colorado (TEX) airport is situated on a mesa in the mountains.

One can look at maps of the area including aerial photos using Microsoft Virtual Earth.  If you click on the “3D” option next to the “2D” option in the upper left of the map display you will be given an option to download and install a 3D plugin for your browser with which you can view aerial photographs in 3D.

Here’s a screen capture of a 3D perspective of the Telluride airport looking northeast using Virtual Earth showing the mesa it’s located upon.

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The 3D perspective is pretty cool, but it does have some issues. Can you see the problem in the following screen capture from an overhead 3D angle?

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Obviously the 3D viewing is a kludge of sorts, as apparently there isn’t enough granularity in the terrain elevation data to ensure that the 3D image is accurate.

If you didn’t see it in the previous image, the following images show more clearly the problem with the 3D display in Virtual Earth.  It displays a huge dip in the runway which corresponds to a low gully that runs down the middle of the mesa intersecting the runway.

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On the airport web page under “Pilot Quick Facts” it says:

Caution: High Terrain exceeding 14,000 feet all quadrants. Exercise extreme caution when southerly winds exceed 15 kts. (rotor over runway, down draft in the middle of runway). Be cautious of down-drafts near abrupt terrain.

But there’s no mention of that dip in the runway at all! Talk about a challenging airport to take off from or land on!

For those interested, here’s a real photo of the runway at Telluride, in which you can see the 64 foot dip in the runway, which obviously isn’t quite as pronounced in the 3D image.

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