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ILS minimums help | Checkride tomorrow need help

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FAA Regulations, General Aviation, Instrument Rating, Private Pilot, Weather

So an ILS approach has a DH of 200' agl.  It also has a minimum visibility requirement of 2,400 RVR.  As per part 91 there are no restrictions to begin an approach regarding weather/ceiling/visibility.  While on the approach tower informs you of a touch down RVR of 1,400.  Before reaching minimums, you have the approach lighting in sight.  Can you continue to land in regards to the current RVR???

Thanks, John. 

6 Answers

  1. Best Answer


    Jim F. on Mar 25, 2017

    Maybe? You stated that you can see the approach lights. With this information alone, the answer is no, but you may descend to 100′ above the touchdown zone elevation, pursuant to FAR 91.175(c)(3)(i).

    Now, if you are able to use the ALS (such as a MALSR) to determine the FLIGHT viability, and you do actually have the required 2,400′, you may land, pursuant to FAR 91.175(c)(2).

    Additionally, as a 121 operator (and 135 is the same), if the tower updates the reported RVR or ceiling to below the required minimums and we are past the FAF, we may continue to the MDA/DA, and land if the above conditions are met.

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  2. John Adamms on Mar 25, 2017

    “Now, if you are able to use the ALS (such as a MALSR) to determine the FLIGHT viability, and you do actually have the required 2,400′, you may land, pursuant to FAR 91.175(c)(2).”

    Thanks, but how would I use the ALS to determine the flight visibility? And how would this override if tower had just reported TD RVR of 1,400.

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  3. Jim F. on Mar 25, 2017

    A typical MALSR extends 2,400′ from the end of the runway (assuming the glide slope is 2.75 degrees or more). So if you are able to see the threshold lights as well as the entire lighting system, then the flight visibility is therefore at least 2,400′. By knowing and understanding which type of light system the runway end is equipped with, you will then be ready to know what to look for when breaking-out.

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  4. Jim F. on Mar 25, 2017

    Oh, and for your second pert, it overrides the tower report as I mentioned above due to the allowance in 91.175(c)(2) because you now know, in real-time, that “the flight visibility is not less than the visibility prescribed in the standard instrument approach being used.”

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  5. John Adamms on Mar 25, 2017

    Thank you very much. Helped me a lot

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  6. Mike Brubaker on Mar 26, 2017

    Not to be nit picky; however, I think it is important that on a CAT 1 approach, it would be DA, not DH. Your minimums are based on an MSL altitude, not an AGL altitude. So many times words or acronyms are used interchangeably, but they are not synonymous. The devil is in the details! Good luck with your check ride!

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