Wednesday, September 15, 2010

Miranda Fire: Flying to the fire (part 2 of 3)

When Larry and I were discussing the Miranda he had this to say about the route he took:
Just for reference,when we get a fire to the east of Medford, the terrain usually climbs faster than we can. So,we take the scenic tour until we can get to about 6,000-6,500 ft, which will get us past Mt. McLoughlin on the Four Mile Lake side (just to the north of the mountain) or on the Lake of the Woods side (just to the south). We took the Lake of the Woods path to Miranda as it's a couple of hundred feet lower than going over Four Mile Lake.

I have spent some time thinking about the best graphic to show to go with Larry’s description about the route he took. I settled on this excerpt from an aeronautical chart (Klamath Falls Sectional Chart) covering the Oregon area. The Federal Aviation Administration (FAA) makes digital raster file versions of Sectional Charts put out by the Federal Aviation Administration, National Aeronautical Charting Office freely available charts on this webpage. These files, probably meant for GPS devices are rather large in size, much too large to reproduce here. However, I was able to use my pdf viewer, to extract the relevant portion of the Klamath  Falls Sectional showing the location of the Miranda Fire.



One of the areas depicted on the chart are different kinds of airspace, e.g. the thick solid purple line around the airport, which I labeled as Medford. Go here to read what I hope is a freely available booklet describing the different kinds of airspace in the U.S. The airport that I labeled Medford, Rouge Valley International Airport, is where Larry’s tanker, tanker 62 is based while on contract with the Oregon Department of Forestry. In flying out of Medford on his way to the Miranda Fire, he had to avoid Mt. McLoughlin (9,495 ft.), that I labeled with the letter A. If you look at the mountain on the chart, you will notice that as the elevation increases, the brown shading darkens. Look around Medford and you will green shading, indicating a lower altitude.

The key here is that Larry has to avoid the higher terrain until he is able to climb to a high enough altitude. Remember that he is flying heavy with a full load of retardant! He did this by flying south of Mt. McLoughlin by Lake of the Woods (“B”). I’m not sure of the exact route he took to the MIranda Fire, labeled on the map. I’m sure that his choice of the route depends on the terrain. But I’m fairly certain that he crossed Upper Klamath Lake, perhaps flying over the area called Modoc Point (see the little purple flag on the east side of the Lake). Modoc Point is a distinctive feature, see the google earth image and you will what seems to be fields at Modoc Point and forested areas to the south of Modoc Point. Pilots flying under visual flight rules often rely on distinctive visual “waypoints” and other features (railroads, powerlines, and roads) noted on the charts.



In closing, I want to acknowledge that aeronautical charts take some getting used to. I spent many hours before, during, and after attending ground school learning my way around aeronautical charts. There were several questions on the FAA written private pilot exam on using aeronautical charts. Passing this written exam, while giving my some confidence, has given me an appreciation for the complexity of flying. I am not going to even try to offer a crash course in using these charts. The AOPA has what I think is a freely available document  here that provides a description of some of the symbols on the chart, with a focus on airspace.

Next up: retardant drops.

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