Message posted by NoOne on August 14, 2007 at 18:16:39 PST:
After many hours of investigation and thought I'm still puzzled by the black marks and the yellow substance on/around the old center taxiway/compass rose. Joerg kindly posted three images of the area; June 2002, July 2003 and our current image dated July 2007. (see link) The 2007 image on its own is interesting, however, adding the 2003 image to the mix makes the whole thing a bit more confusing. . The taxiway/compass rose area has no paved taxiway connections to any other structures. The area also has no paved roads connecting to it. So,, what are, and what's making, the black marks? And what is the yellow substance and how is it being deposited? Is the yellow substance connected to the black marks? Construction related? Perhaps the best guess. There has been much construction work since 2002 and lots of it seems to be apron, taxiway, runway and pad work. Perhaps the black stuff is just bitumen. But why have trucks go around the compass rose? There doesn't appear, at least in the 2003 image, to be anything there. Used for UAV activities. Maybe but the old taxiway "runway" (East/West) is cross the prevailing wind direction (KTPH 15/33, KTNX 14/32 and groom 14/32). In addition there are buildings under/near the approach and departure patterns of the old taxiway. And how/why would they land right on the edge of the taxiway? And how could there be that much rubber deposited - one might expect to see a huge pile of used tires right near by. Yellow substance. It almost looks like an airborne deposit. Wind blown paint, combustion residue, poor alien toilet habits? Hummm - fun! NO? Some general information: Taxiway Length 1,200' Compass rose section Placement - mid Taxiway
. The black marks are not apparent in the 2002 image.
. In the 2003 image the black marks seem well defined and perhaps the 2003 image gives a clue about what the black lines are or how the black lines are being used.
. In the 2003 image (quite clear) and even in the 2007 (look closely) there seems to be an "entry/exit" arc that loops from the taxiway into the compass rose that is different to the arc that seems to be centered on the compass rose.
. Both the 2007 and 2003 images look as if something goes around the compass rose quite distinctly different than using the compass rose area to change direction. The top of the donut isn't flattened.
. It seems that the yellow substance also starts to appear in the 2003 image (around the bottom of the compass rose).
. The 2002 and 2003 images don't appear to have any structure in the middle of the compass rose area whereas in the 2007 image there may be something there.
. Starting with the 2003 image some of the long black marks on the taxiway are right on the very edge of the taxiway - not centered on the taxiway. There may be pairs of marks but maybe not. In the 2003 image the marks at the top (north edge) of the taxiway are darker than those on the bottom edge (south), however, in the 2007 image the opposite seems to be the case. The black marks on the taxiway appear to be about 2.5'-3' wide.
Width 50'
East/West heading of 5/23 (4 degrees of perpendicular to runway)
Expansion joints (blocks) - 8'x8' (6 across making the taxiway 48' wide)
Depth (off taxiway) 200'
Compass circle diameter 120' (radius 60')
Compass circle center 140' from taxiway edge
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