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FSX RNAV & Autoland

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Will the FSX MD11 perform an autoland on a RNAV approach to a runway the way it will on a ILS approach to a runway?When entering the RNAV approach information where do you find the minimum proof in feet figure to insert? Would it be 475', this figure is in the lower right of the attached RNAV approach from www.airnav.com.Rod Storer

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RNAV/GPS approaches are not certified for autoland events. GLS has been proven capable for autoland, but only in VMC at the moment. Furthermore, I can almost guarantee that there will never be an approach to an autoland on DCA's runway 19, not mentioning that you'd never land an MD-11 there anyway.

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So Kyle, I am not sure if you answered the question or not. The question is not will a real world MD11 do an autoland with an RNAV approach.The question is will the PMDG FSX MD11 do one? Three possible answers are; yes, no or maybe you will just have to try it.Rod Storer

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The MD-11's AFS will not engage a Land Mode (Dual/Single) in the absence of an ILS signal, so the answer to your question is no. You could use RNAV to fly the approach and more or less line up in the direction of the runway, but it would be significantly less precise than the alignment provided using an ILS localizer.

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As far as i know at the moment, RNAV approaches are still considered Non-Precision approaches. In other words, they dont provide a vertical guidance. And still have a MDA/H rather than a DA/H They will give you step downs as you approach but still is no Vertical guidance. an ILS has the glideslope to provide the vertical guidance down.RNAV is being developed into a virtual ILS i believe. As the accuracy of the GNSS system is improving, the location of an aircraft can now be down to half a foot. So RNAV approaches could be made to follow a "GNSS glide slope"as is the aircraft moves closer to the runway. It would be considered a constant step down really.There would have to be some additions to the aircraft though im sure. Such as probably at least 3 different GNSS receivers to make sure that they all agree on the position of the aircraft. A advanced FMS to be able to fly down one of these "GNSS Glideslopes" and also produce a G/S for the pilot to follow.

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As far as i know at the moment, RNAV approaches are still considered Non-Precision approaches. In other words, they dont provide a vertical guidance. And still have a MDA/H rather than a DA/H They will give you step downs as you approach but still is no Vertical guidance. an ILS has the glideslope to provide the vertical guidance down.RNAV is being developed into a virtual ILS i believe. As the accuracy of the GNSS system is improving, the location of an aircraft can now be down to half a foot. So RNAV approaches could be made to follow a "GNSS glide slope"as is the aircraft moves closer to the runway. It would be considered a constant step down really.There would have to be some additions to the aircraft though im sure. Such as probably at least 3 different GNSS receivers to make sure that they all agree on the position of the aircraft. A advanced FMS to be able to fly down one of these "GNSS Glideslopes" and also produce a G/S for the pilot to follow.
This already exists - look up LPV approaches... IAN in the NG does it as well - it's a computer generated glideslope - the DH isn't as low as it is with the various ILSes, but it does have vertical guidance.

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Ah thanks for the info Ryan! Reading up on the wiki, that it is to have at least 16 meter horizontal accuracy and 20 meter vertical accuracy 95 percent of the time! Now i would of thought that is still quite a lot of inaccuracy, especially when on approach. Would hope that those numbers in meters would be feet!I'm sure once GPS,GLONASS,and Galileo all become fully public, then we can maybe expect the accuracy to increase and the possible CATIII RNAV approaches becoming a possibility.Perhaps we are seeing the end of ILS/VORs and NDBs soon!

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I'm sure once GPS,GLONASS,and Galileo all become fully public, then we can maybe expect the accuracy to increase and the possible CATIII RNAV approaches becoming a possibility.Perhaps we are seeing the end of ILS/VORs and NDBs soon!
NDBs are done. You'll note that most in the United States are going out of service and aren't being fixed/replaced. They're just phasing them out by means of letting them die (unless they serve an important role for another approach).I doubt ILS will go anywhere any time soon. There's something to be said for the antenna being fixed at the end of the runway, without need for aircraft-based monitoring (like GPS's RAIM).GPS already has the precision necessary, but only in military applications, and I doubt that'll become public. Interestingly, civilian GPS actually has error built into it, keeping the advantage on the military side. For that reason, we also already have another system to remove that error, called WAAS. WAAS is a ground-based transmitter to add precision to the satellite based GPS calculations, which allows GPS to have approach-like precision. LAAS is being developed to meet the goal you mention, of being CAT-III capable.

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Nice. Shows you how much I've paid attention. Go me!

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This already exists - look up LPV approaches... IAN in the NG does it as well - it's a computer generated glideslope - the DH isn't as low as it is with the various ILSes, but it does have vertical guidance.
At my home airport, the (CAT 1) ILS and LPV approaches have the same mins...

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