Anyone know what this came out of?

Discussion in 'Aviation' started by bleep323, Apr 9, 2008.

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  1. Hi guys,

    Now I'm sure this use to belong to the RAF and probably many moons ago too but knowing most of you guys who work in aviation have an interest in it outside of work I thought I'd try here before nipping over to e-goat.

    This was given to me a few years ago and I was told it came out of a Spitfire but I'm not so sure, the back I think is made from Bakelite although it is black and Bakelite was usually brown.

    Written on the bottom is the following.

    Navigational Computer MK3D.

    REF. No. 6B/180

    And thats all I have.

    Sorry I did try to add a pic but its not having it.
  2. Surely its a Morris Minor sat nav?
  3. I'd guess that it's a drift-chart (for want of a better word). In a cross-wind, the compass bearing doesn't show the direction of flight, merely the attitude of the aircraft.

    Plot compass bearing, airspeed and wind vector (speed and direction) on the chart and somehow you end up with direction of travel and ground speed.
  4. Yup. You needed one of those in a Morris Minor.
  5. You are quite correct, puttee.

    The main 'dial' certainly looks like a wind drift correction dial. And as you suggest, its used to work out 'heading to fly' taking into account a known wind.

    We still get issued a similar device called a 'whizz wheel', 'Dalton Computer' or officially, Computer Dead Reckoning MK 4A (actually the same as the one in the link provided, two below the subject). That is basically a rotary slide rule used for working out all manner of stuff as well as having the wind drift corrector on the rear. Cant beat old fashioned MDR. :)

    Where did you get it from bleep?
  6. Yep thats the one puttees. So having looked at the link and seen that it would have been used at speeds of up too 400 Knots it was probably used in just about anything that flew at the time.

    I was given it by my brother in law, I think he was given it by a guy he was doing some building work for. At the time I was deciding whether to join the RAF or the Army, I was at the time a complete plane spotter and this old chap thought it might swing to join the RAF but I swing the other way so joined the Army.

    Thanks for the info and description of what it did.