Approach Question

Don, just to clarify what you said for my own sake...

You are saying that if the prevailing vis is less then mins but the RVR on a runway is good, the only runway you can land on is the one with the RVR? And RVR only goes one direction so you couldn't land on 27 if the only RVR given was for 9? I just had a "discussion" with a captain about this. It ended up clearing up before we got there so it wasn't an issue but he was deadset on applying an RVR from one runway to a different one.
 
BobDDuck said:
but he was deadset on applying an RVR from one runway to a different one.
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Where do they get these people???

I once "knew" someone that had a CA completely disregard an out of date FOM and complete a type of approach for which the aircraft wasn't authorized for (ignoring the fact that the FOM was referring to a different aircraft to begin with...). Meanwhile the FO was reading straight out of a CURRENT FOM that that type of approach wasn't authorized....

We can't make them listen to us. We can do our best to keep them out of trouble and get it on tape but they make the ultimate decisions - it's their prerogative.
 
Hah... Both our companies flew the same "other" airplane in the past. I had a captain tell me once that he was planning on the ILS 26 in PHL because he used to do it all the time in the dork and the approach hasn't changed at all. Uh yeah, but the airplane has by a ref speed of 25 knots and 2 landing catogories. Grrr.

You can lead a horse to water... :insane:
 
"but he was deadset on applying an RVR from one runway to a different one"

I think the Capt was right. I'll try to remember to look it up tonight if anyone is in disagreement. RVR is runway specific to include only the end of the runway it's "advertised" for.
 
DE727UPS said:
"but he was deadset on applying an RVR from one runway to a different one"

I think the Capt was right. I'll try to remember to look it up tonight if anyone is in disagreement. RVR is runway specific to include only the end of the runway it's "advertised" for.
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Both your posts are saying different things. bobdduck is arguing that you can't use RVR from one runway and apply it to another. The CA had a different opinion. You agree with the CA, but then say RVR is runway specific? Or are you saying that it's OK to use a report for RW36 as the same for RW18 without getting a seperate report?

Also, my guess is if you have RVR for RW36 you'll have RVR for RW18. You'd just have to ask, so it's sorta a moot point. But you'd still need an RVR report for the specific runway IMO, otherwise you'd have to use the tower reported vis. I would definately like a definitive answer to that. My FOM is at work so I can't look it up.
 
"my guess is if you have RVR for RW36 you'll have RVR for RW18"

That wasn't the case in the first post.

I've always felt like runway 18 and runway 36 are two different runways. If there was once chunk of asphalt would ATC clear you to taxi to "the runway" or to "runway 18" or "runway 36". One chunk of asphalt is two different runways and that's how I've always viewed it. Sorry for the confusion. Touchdown RVR only applies to the end of the runway you're touching down on and nothing more.
 
DE727UPS said:
I've always felt like runway 18 and runway 36 are two different runways.
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Definately, until you start talking about derived alternate mins. 2 facility vs. 1 facility, suitable, etc. Then combine that with 3585. Ouch my head hurts now. Thank god for dispatchers :D!
 
DE727UPS said:
I've always felt like runway 18 and runway 36 are two different runways. If there was once chunk of asphalt would ATC clear you to taxi to "the runway" or to "runway 18" or "runway 36". One chunk of asphalt is two different runways and that's how I've always viewed it. Sorry for the confusion. Touchdown RVR only applies to the end of the runway you're touching down on and nothing more.
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That's exactly how it was taught to me. If you take a 12,000ft runway, RVR could be completely different on both ends, therefore the reported RVR is only valid for the reported runway.

RVR is measured by transmissiometers and there are usually three of them along the edges of the runway, so they can give indications in "thirds". One for the touchdown zone, midpoint and stop-end, like: R24L/700 500 650 R24R/750 400 800. RVR is usually reported when the visibility drops below 1500m or less, or when fog is reported or forecasted. The midpoint and stop-end values are not published when they have an equal or higher value than the touchdown zone and as long as they are above 400m. (R 200 500 600 would only be reported as R 200). If the RVR drops below 50m, they code it with RBLW50.

Sorry, I don't know the US values for the distances on top of my head, but I hope it makes sense, nevertheless.

And back to the original question: the regs over here in Europe would allow to convert RVR to vis, however this may also be different from operator to operator. Many operators even produce their very own approach charts and can print higher mins for different aircraft, if they think it is necessary.
 
wheelsup said:
Definately, until you start talking about derived alternate mins. 2 facility vs. 1 facility, suitable, etc. Then combine that with 3585. Ouch my head hurts now. Thank god for dispatchers :D!
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Different vs Separate. Different runways are 9 and 27 same pavement.
Separate is 27R and 27L. Totally different strips. Our ops specify different runways(if I remember right) for alt mins. the problem is a lot of time they have the same facility running both locs. therefore only one fac. anyways....I just wanted to clairify different vs separate runways.
 
I'm not familiar with the terms "different" and "seperate", must be a 135 thing. Does AMF use derivied alternate mins and/or exemption 3585? That was what I was referring to - when using derivied alternate mins you have to add 400' + 1 mile for for one facility and 200' and 1/2 for 2 facility, in addition when using the two facility mins they must be suitable (so you must account for wind etc. while the 1 facility just has to be "favorable", which just assumes still air - as crazy as that is!! you can pick an approach to a runway which is forecasted to have a 20 kt tailwind and it would be legal, but not smart which is why the CA has to sign the release!). 2 facilities could be the same patch of pavement but the ILS's must have their own ident, ie R/W 09 ILS 109.9 and R/W 27 ILS 109.10. If not, they are considered a single facility. 3585 deals with dispatching to airports when the conditional section of the TAF is below mins, by a certain margin. Although I'm just pulling this off the top of my head so I might have some stuff mixed up!!! Like I said that goodness for dispatchers :)!!
 
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