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Wood Shield For Magnetic Field?

  1. Oct 8, 2015 #1
    So, I was watching PBS's Nazi Mega Weapons, and they were discussing the V-1 terror drone when they said something that made me scratch my head. They said that the Nazis initially had problems with the compass that facilitated navigation because of magnetic interference from the metal in the V-1 chassis. The part that confused me is that they solved this problem by encasing the compass in a wooden shell. I didn't think that an insulator could stop magnetic field lines. In fact, I'm pretty sure of it, unless we can make monopoles now. Any speculation on how this worked, or if the show meant something else when they said this?
     
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  3. Oct 8, 2015 #2

    andrewkirk

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    Are you sure the wood was a shield? My interpretation of what you wrote would be that the part of the shell of the drone that surrounded the compass was made of wood so that the compass was outside the metal chassis, yet still securely attached to it. ie the wood was to put the compass where the metal chassis wouldn't shield the compass from the Earth's magnetic field.
     
  4. Oct 8, 2015 #3

    nsaspook

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    Maybe the metal was blocking the earths magnetic field and the use of wood allowed the compass to work properly.
     
  5. Oct 8, 2015 #4

    Bystander

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    Consider the source; consider the number of different conflicts in which the source has sunk HMS Barham. Ignore source soundtrack and examine raw footage.
     
  6. Oct 8, 2015 #5

    berkeman

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    You don't want to "stop magnetic field lines" from reaching the compass, right? :wink:
     
  7. Oct 8, 2015 #6

    SteamKing

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    IDK what this program was talking about, but the V-1 was guided by an on-board gyrocompass, which is not the same thing as a magnetic compass.

    https://en.wikipedia.org/wiki/V-1_flying_bomb#Guidance_system

    A gyrocompass works by spinning up a disk to a very high speed, so much so that the disk maintains its original orientation even though the vehicle carrying it may be moving about.

    https://en.wikipedia.org/wiki/Gyrocompass

    Gyros are used to guide all sorts of vehicles, from aircraft to ships to missiles, etc.

    The V-1 guidance system was crude and only allowed the craft to fly on a heading set before launch. The range to the target was counted down by a spinner in the nose which cut off fuel to the ramjet when the missile had traveled the required distance. The V-1 then dived unpowered into the target after that point.
     
  8. Oct 9, 2015 #7

    Gaz

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    Steamking. The gyroscope remained true on the basis of feedback received from a magnetic compass. found that on your wiki page link =)
     
  9. Oct 9, 2015 #8

    Gaz

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    Wouldn't the wooden frame create extra distance between the compass and the metal rocket ? That would surly decrease the magnetic interference. It would probably help somewhat with vibrations to I'm guessing?
     
    Last edited: Oct 9, 2015
  10. Oct 9, 2015 #9

    CWatters

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    Google found a description..

    http://www.zenza.se/vw/

    So basically they used wood/duralumin instead of steel because steel would affect the compass. Wood/duralumin is also lighter than steel

    There is actually a photo of the wooden cover for the V1 compass on this page. Sorry I can't link direct to the photo. Search the page for "V1 wooden nose"

    http://spitfirespares.co.uk/Rockets 1.html
     
  11. Oct 9, 2015 #10
    Emerging consensus is that it functioned as a spacer and non-ferrous enclosure, rather than any kind of "blocking" which seems to make sense, but is an oddly disappointing answer somehow.
     
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