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Help with 107 - Elevation

Discussion in 'Rules and Regulations' started by Shep, Oct 6, 2016.

  1. Shep

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    Folks, I am studying for my 107 test with materials that are available online. I am having some trouble with reading elevations. Here is a sample question from the 3DR site. I know the answer simply by memorization but I don't know how to "read" how they got there :)

    Here it is as their very first question: LINK

    Many thanks ahead of time.
    Shep
     
    #1 Shep, Oct 6, 2016
    Last edited: Oct 6, 2016
  2. BigAl07

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    Shep I'm afraid we may not all see the same questions as you are seeing. I think the site "randomizes" the questions and none on the ones on the page when I went there made any sense compared to your request.

    Sorry :)
     
  3. Shep

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    Thanks for the heads up! Let me try this again a little different way:

    I will post a screen shot of the question AND the map.

    Screen Shot 2016-10-06 at 1.27.27 PM.png Screen Shot 2016-10-06 at 1.27.59 PM.png
     
  4. Richard R

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    Look at the airports near point 1 and along the path to point 2. Their elevating range from 1860 to 2248 and back to 2065 ft msl. I would go with the first choice.
     
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  5. Roadking

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    I'm pretty sure that map has a legend that shows the color of the various elevations. Look in the upper corner on the original map.
     
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  6. Shep

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    The answer is - 2,000 feet to 2,500 feet MSL - I just don't know how they are getting that answer.........HELP :)
     
    #6 Shep, Oct 6, 2016
    Last edited: Oct 7, 2016
  7. Shep

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    If you are talking about this (attached) it doesn't really narrow that answer down. Screen Shot 2016-10-06 at 6.01.20 PM.png
     
  8. Multicoptertec

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    See those large blue numbers? Those are the max terrain altitudes plus 300' for safety. So, you have a big 2, little 8 near area 2, which is 2800', -300, = 2500'. Not sure where they get the 2000' from, perhaps an elevation color code chart not shown.


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  9. Richard R

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    F
    they don't show you the legend in the test question. Look at my first response.
     
  10. Multicoptertec

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    Ah, that color code shows that the tan second box range, which is the same color as the map, has a floor of 2000'.


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  11. Richard R

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    Ok, now I'm confused. Your example has 2000-2500 as the first choice, which is the answer that I suggested in my first response.
    those numbers are the highest point within the square, not nessicarily in the area in the question.
     
  12. Multicoptertec

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    Your test manual will have a legend in the front of the book, it is not on each chart.


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  13. Richard R

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    Those are "maximum terrain elevations" within the quadrant and include towers, other obstacles. There is no '300' added feet for margin.
     
  14. Multicoptertec

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    Square? What square are you referring to?


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  15. Richard R

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    They do add 200' when a feature or obstacle is the highest point in a section.
     
  16. Multicoptertec

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    MEFs are determined by taking the point of highest elevation within a quadrangle, adding 100 feet for vertical error, then adding the height of the highest obstacle in the quadrangle or 200 feet, whichever is higher, then rounding up to the next hundred feet.[2]


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  17. Richard R

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    Sorry, they are called quadrants and are marked but the ticked lines on the sectional the lines are 30 seconds (1/2 degree) apart.
     
  18. Richard R

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    Sorry, you're right.
     
  19. Richard R

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    Okay, so with all the discussion above, you should be able to figure out now that the correct choice would be 2000-2500. You know that the floor starts at 2000 from the color legend. The highest airport in the area of interest is about 2300 and using the MEF and taking into account the 'safety' margin, you get 2500. Thanks for the question, lead to some interesting discussion.