If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
|
Thread Tools | Display Modes |
#11
|
|||
|
|||
Any airport does not qualify. Most of those airports have "A-NA" on
the chart, which stands for "Alternate - Not Authorized". Actually, that's not quite right. The A-NA refers to the approach, not the airport. It is quite common to have some approaches to a given airport marked A-NA, and others not so marked. In that case, the 'best' approach among those not marked A-NA is used to determine alternate minima for that airport. If all approaches are marked A-NA, then the only remaining approach is a visual. The alternate minima for a visual are weather sufficient for descent from MEA to a landing under basic VFR. Those minima are always authorized, so any airport is an authorized alternate - the only question is what the alternate minima will be. There are airports where the alternate minima require 10,000' ceilings (mountain MEA's and valley airports will do that) but they are still authorized. I agree with you that there are not any airports within a short distance of DAY that would be useful alternates in conditions that would actually require you to file an alternate for DAY. Michael |
#12
|
|||
|
|||
An different example of this was Port Columbus International in Columbus
OH (KCMH). CMH had one 10,000 foot runway and one 6,000 foot parallel runway (it now has the 6,000 extended to 8,000). Because the 6k runway was too short for most airliners, the airline company operations manuals forbid their Captains from filing CMH as an alternate in the event the 10k runway was taken out of service. Michael wrote: Actually, that's not quite right. The A-NA refers to the approach, not the airport. It is quite common to have some approaches to a given airport marked A-NA, and others not so marked. In that case, the 'best' approach among those not marked A-NA is used to determine alternate minima for that airport. If all approaches are marked A-NA, then the only remaining approach is a visual. The alternate minima for a visual are weather sufficient for descent from MEA to a landing under basic VFR. Those minima are always authorized, so any airport is an authorized alternate - the only question is what the alternate minima will be. There are airports where the alternate minima require 10,000' ceilings (mountain MEA's and valley airports will do that) but they are still authorized. I agree with you that there are not any airports within a short distance of DAY that would be useful alternates in conditions that would actually require you to file an alternate for DAY. |
#13
|
|||
|
|||
Peter Duniho wrote: "Andrew Sarangan" wrote in message 1... But you have to first decide whether you need an alternate before going to the trouble of picking one. So? Any airport does not qualify. Most of those airports have "A-NA" on the chart, which stands for "Alternate - Not Authorized". FAR 91.169 doesn't say anything about whether an alternate is authorized or not. ANY airport is authorized, as long as VFR conditions from MEA to landing are forecast. OK, I may show my ignorance here. Isn't the approach procedures constitute FAR 97? If a chart says 'Alternate Not Authorized', does it not effectively disallow that airport from being listed as an alternate? The thread was a follow-up to 'flying to hamvention' thread. If you look at the Dayton area, there aren't any airports within a short distance of DAY that does not have an "A-NA" on it. Ideally, an alternate would not be a short distance from your destination anyway. After all, if the weather's too poor for landing at your destination, often it will be at a nearby airport as well. I agree with you on that. Alternate should be selected where the wx is likely to be significantly different. |
#14
|
|||
|
|||
"Andrew" wrote in message
ups.com... OK, I may show my ignorance here. Isn't the approach procedures constitute FAR 97? If a chart says 'Alternate Not Authorized', does it not effectively disallow that airport from being listed as an alternate? The "not authorized" applies to the approach, not the airport (as Michael already pointed out). Forecast VFR conditions allow ANY airport to qualify as an alternate under the default visual approach that exists at every airport. If you have an airport for which every approach says "not authorized", then the visual approach is the only way to use that airport as an alternate. But even in that case, the airport is not ruled out as an alternate, except due to the weather forecast. It is otherwise eligible. Note that airports without instrument approaches don't even have a chart where one could find "A-NA" listed on it. As much as I hate to bring logic into a discussion about the FARs, it just wouldn't make sense for an airport with an instrument approach to not be authorized as an alternate (even under VFR conditions), even as one without is automatically granted qualification as an alternate (under 91.169). So, to reiterate: having one or more approaches at an airport listed as "A-NA" does not disqualify the airport. It just disqualifies the approach. And the visual approach is always authorized (since it doesn't rely on any monitored navigation equipment, and an area forecast is sufficient for using for alternate decision-making). Pete |
#15
|
|||
|
|||
Good job Pete.
Alternate airport, not alternate approach. http://www.aopa.org/pilot/features/ii_9807.html AOPA's article on the subject. It points out that FSS is a good place to start asking for alternate suggestions as they have the forecasts right in front of them. When I file and am required to list an alternate, the first line of thought that goes through my mind is "why" I need an alternate.... What weather phenomenon has created the conditions, is it moving, which direction, and how fast? A wide area of like conditions forcast to remain the same or deteriorate will usually tell me to pick an alternate that is enroute prior to my original destination, however, if my original destination is in a low lying area, near water and possibly surrounded by ground fog, an airport close by but at a higher elevation may be the ticket. Same theory for lake effect snow, go where it isn't! I'm usually better off filing an alternate further inland than along the lake even though I will be going past my original destination. I also try to pick alternate airports that have more services than my original destination, if the weather is bad enough that I can't get into Podunk on their VOR or GPS approach I know that the weather is worse than forecast and my alternate will be the closest ILS with radar but hopefully in the direction of more favorable conditions. Note that once choosing the alternate the weather at the alternate then must meet the non precision 800/2 and precision 600/2 rule. But to steal a line from AOPA's article "It is also worth noting here that alternate minimums apply for planning purposes alone. If you're airborne and heading to the alternate, published minimums will now apply." Jim |
#16
|
|||
|
|||
Peter Duniho wrote:
"Andrew Sarangan" wrote in message . 61... If the destination does not have an instrument approach you must pick an alternate. If the destination has an instrument approach, then you don't need an alternate unless the the weather is worse than 2000' ceiling or 3SM vis +/1hr of the ETA. (ie if the forecast is worse than VFR then you need an alternate). The above is not "the process for choosing an alternate". It's the process for deciding whether you NEED an alternate. You can't pick any airports as an alternate. Only a few airports qualify as an alternate. Wrong. Any airport qualifies, as long as the forecast is for VFR conditions from the descent from MEA all the way to the ground. Beyond that, lots of airports have instrument approaches and thus qualify as an alternate under lower forecast conditions. Even in IFR conditions, it's far from true that "only a few airports qualify as an alternate". Pete We have a local airport (KGYI) with an ILS and it does apply as an alternate. At the time it didn't have weather reporting, but now has a AWOS -- Regards, Ross ________________________________________ 972.952.3170 Phone 972.949.9249 Pager 972.952.2574 FAX McKinney / Wing A2 North @ 48v72 |
|
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Airports Rated Critical Unsatisfactory: Given Black Star Rating | Michael Ravnitzky | Piloting | 0 | February 3rd 05 03:34 AM |
"I want to thank Mayor Daley for tearing down his airport." | Larry Dighera | Piloting | 13 | January 24th 05 04:00 AM |
Time to revamp traffic patterns at non-towered airports? | Ace Pilot | Piloting | 47 | February 11th 04 03:16 PM |
Alternate requirements | Anthony Chambers | Instrument Flight Rules | 8 | September 17th 03 09:45 PM |
fatal bird strike | StellaStar | Piloting | 9 | July 13th 03 09:41 PM |