VOR and variation
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VOR and variation
Hello,
In a book I've read the following about an RMI:
If the aircraft's variation is different from the VOR station's variation, the indication of the relative bearing is incorrect, but the QDM indication is still correct.
Does this mean that if you have a variation difference of 20° between the aircraft's position and the VOR position, you will be flying in an arc ('homing') to the VOR if you follow the VOR pointer on the RMI (the QDM indication)?
This all in no wind conditions.
Thanks.
In a book I've read the following about an RMI:
If the aircraft's variation is different from the VOR station's variation, the indication of the relative bearing is incorrect, but the QDM indication is still correct.
Does this mean that if you have a variation difference of 20° between the aircraft's position and the VOR position, you will be flying in an arc ('homing') to the VOR if you follow the VOR pointer on the RMI (the QDM indication)?
This all in no wind conditions.
Thanks.
Last edited by Spir4; 9th Jun 2013 at 10:23.
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Hi Spir4,
If the difference in variation was 20 degrees between the VOR and the aircraft, then flying with the needle pointing directly upwards would send you away by 20 degrees initially.
If you wanted to fly a constant QDM, then your heading would have to be 20 degrees away from the needle initially (seen as apparent drift), and as the difference in variation reduced to zero, then you'd finish with the needle pointing directly ahead.
If the difference in variation was 20 degrees between the VOR and the aircraft, then flying with the needle pointing directly upwards would send you away by 20 degrees initially.
If you wanted to fly a constant QDM, then your heading would have to be 20 degrees away from the needle initially (seen as apparent drift), and as the difference in variation reduced to zero, then you'd finish with the needle pointing directly ahead.
Last edited by rudderrudderrat; 9th Jun 2013 at 16:59. Reason: tidy up