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I've been looking at a couple of the photos of the Port Royal on the shoal 
south of the airport. In one of them (attached), you can clearly see the 
skyline of downtown Honolulu not far in the distance. The airport and its 
main runway were just to port. This was a visually "busy" environment at 
night with all sorts of airport lights, city lights, and the bright lights 
from the sewage treatment plant and the vast port facilities dead ahead. It 
got me wondering just what it would all have looked like from the bridge of 
the vessel that night. And of course to find out, I needed to know just where 
they were. This is where it gets fun...

I prowled around on the web for a while yesterday looking for photos of the 
vessel on the reef from various angles. There are a couple of photos taken 
from the tugs and salvage vessels nearby, and they offer some hints. There 
are also a number of photos taken with the airport in the foreground, but 
these don't seem to help much since that runway doesn't have many 
identifiable features visible from ten feet above sea level. Then I found a 
couple of photos taken with telephoto lenses apparently from tall buildings 
in downtown Honolulu that are quite useful. I patched them together into a 
couple of composites (also attached). And one of them, no doubt taken for its 
artistic qualities, includes the setting sun! That gives us an angular scale 
and a good estimate of azimuth. In the foreground of the daylight portion of 
the image, you can see a bunch of containers all labeled "Matson". So go to 
Google Maps and ask for "Matson Honolulu HI". That takes you right to their 
big lot on Sand Island between the airport and downtown Honolulu. Line things 
up just right, and we should be able to figure out just where the Port Royal 
came to rest on the shoals on February 6, 2009. There's some entertaining 
geometry and navigational calculations here. I won't spoil it by giving my 
results. Besides I would like to see what some of you get independently. One 
warning: the facilities at the Water Treatment Plant on Sand Island have been 
significantly expanded since the last imagery was acquired for Google 
Maps/Google Earth. That big egg-shaped structure is a "sludge digester" and 
it's new. See if you can find the wind sock for the helipad (I think it's a 
wind sock at least).

Some questions to ponder: what is the true bearing from that big circular 
sewage tank in the mid-ground out to the Port Royal? Can you do a "dip short" 
or similar to figure the distance to the vessel? Can you make a guess how 
high the observer was who took the photo (assuming it was taken from the 
central area of downtown Honolulu)? And finally, with all the available 
evidence, what were the latitude and longitude of the Port Royal's bow and 
stern while she was parked on that reef?

-FER

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