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[viralQuiz id=5]

John Zimmerman
12 replies
  1. Dave
    Dave says:

    This is great stuff ! Thanks. I found out a lot of things I had forgotten about sectionals, but I am confused about one of the answers. According to the sectional, the magenta circle indicates “Class E Airspace with floor 700 ft above surface that laterally abuts 1200 ft or higher Class E Airspace” . Wouldn’t this indicate the correct answer is that Class E Airspace begins 700 ft above the surface ? If I’m missing something, a little more explanation in the answers would be appreciated.

    • Warren Webb Jr
      Warren Webb Jr says:

      You’re correct. ‘Class E airspace starts at 700 feet AGL’ is the one that turned green for me. Try reloading the quiz.

  2. William Dougherty
    William Dougherty says:

    FROM: Massey Aerodrome MD1  Website: http://masseyaero.org
    c/o William G. Dougherty
    TO: John Zimmerman Air Facts journal
    RE: Sectional Chart Quiz

    Hello Mr. Zimmerman, Massey Aerodrome is a 3000’ x 100’ public use grass airport on the Eastern Shore of Maryland. We are a “Hobby Airport” in that no businesses are operated here but we do have a workshop, a museum, we conduct Young Eagles Days and we are planning to start a program offering the Boy Scout Aviation Merit Badge. When I stumbled on the Sectional Chart Quiz I was hoping I might be able to use it with the Boy Scouts but it was immediately obvious that it wasn’t intended for rank novices. Any chance you could create a Sectional Chart Quiz on the basics, appropriate for 12 – 17 year olds? Actually quizzes on any of the basics would be helpful if you happen to know of any sources. I’ve been advised that I don’t want to be conducting classes behind desks, it is imperative to maintain an interesting, fun atmosphere in order to hold their attention. I’ve not found a lot of material on-line that fits the bill and while I don’t want to reinvent the wheel, my research hasn’t yet produced what I believe is needed. I’ve tried EAA and the Boy Scouts themselves without success. I’m looking into Women in Aviation Intl. who have a workshop program but am waiting for a reply.

    Any thoughts or direction? The merit badges are only supposed to introduce the subject so the scout can find out if they want to pursue it further.

    Any help will be appreciated.
    Bill Dougherty

  3. Denecke Hans
    Denecke Hans says:

    Very much appreciated, please more of this kind of quiz, thank you
    It shows how much one keeps or looses with time

  4. Don Woodbridge
    Don Woodbridge says:


    Let’s talk about this question a little more: “Does the Maximum Elevation Figure (MEF), which shows the highest obstacle within a quadrant, include any buffer?”

    From the FAA’s AIM Aeronautical Chart Users Guide:

    “Aeronautical Information Specialists use the following
    procedure to calculate MEFs:

    When a manmade obstacle is more than 200’ above the highest terrain within the quadrant:

    1. Determine the elevation of the top of the obstacle above MSL.
    2. Add the possible vertical error of the source material to the above figure (100’ or 1/2 contour interval when interval on source exceeds 200’. U.S. Geological Survey Quadrangle Maps with contour intervals as small as 10’ are normally used).
    3. Round the resultant figure up to the next higher hundred-foot level.”

    (Note that the 100′ is not a buffer, but allowance for possible vertical error) [dw]

    This would seem to indicate that depending on the MEF to keep you 100′ above the maximum terrain is a dangerous assumption.

    If the highest feature is a natural obstacle such as a tree, there is an added a buffer for uncharted obstacles, but it is 200′, not 100′. I suppose that this is because trees tend to grow over time.

    “When a natural terrain feature or natural vertical obstacle (e.g. a tree) is the highest feature within the quadrangle:

    1. Determine the elevation of the feature.
    2. Add the possible vertical error of the source to the above figure (100’ or 1/2 the contour interval when interval on source exceeds 200’).
    3. Add a 200’ allowance for uncharted natural or manmade obstacles. Chart specifications don’t require the portrayal of obstacles below minimum height.
    4. Round the figure up to the next higher hundred-foot level.”

    Bottom line is that the MEF is not guaranteed for obstruction clearance like the MOCA.


    • John Zimmerman
      John Zimmerman says:

      Valid points, Don. The object of the question was to make us think about what those quadrant numbers mean. Many pilots think it’s the height of the highest obstacle. It really isn’t, although you’re right to be conservative when interpreting the buffer.

  5. Vivien Jones
    Vivien Jones says:

    This is an excellent journal. The quiz is brilliant as it is making us all refresh our knowledge. Would it be possible to have 2 sets of quizzes 1 set for VFR and 1 set for IFR.

Trackbacks & Pingbacks

  1. […] Let’s review this quickly so we understand the problem clearly. When Orville and Wilbur were flying, everything was G airspace or “go for it”; no IFR, no serious restrictions. But as the instrument flight system was created, the 3 mile visibility minimum was created in controlled (IFR) airspace and the “buffer” of 2000 horizontal, 1000 above and 500 below was created to provide separation VFR/IFR. Visual separation was at least possible for faster moving IFR plane transitioning into visual at a smaller, non-tower; and remember no communications are required. These fields look like Watertown if an ILS is in place; protection to the surface. On the other side of the equation is the IFR approach plate which seemingly insures a safe descent from the clouds. […]

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