Alternate selection

[spinfire]

So, I'm just getting into the meat of my instrument training. We've discussed the alternate requirements. I won't be with my instructor until Saturday but I was at work looking out at KBED today (my work has a nice view of the airport!) in the soup and wondering if there are any good flight planning tools to select a legal alternate. Basically most of New England was IFR or LIFR and selection of an alternate would not be obvious. If forced to do it manually my approach would be to pull up skyvector and look at major airports like Manchester, Portland, Albany, etc, and look for the nearest which is forecast to be above alternate minimums at my estimated time of arrival. But it would be awesome to have a flight planning tool that could tell me the airports nearest my intended destination that meet the alternate requirements. I did a quick google search but found nothing useful. Does such a tool exist?

 

[azure]

So, I'm just getting into the meat of my instrument training. We've discussed the alternate requirements. I won't be with my instructor until Saturday but I was at work looking out at KBED today (my work has a nice view of the airport!) in the soup and wondering if there are any good flight planning tools to select a legal alternate. Basically most of New England was IFR or LIFR and selection of an alternate would not be obvious. If forced to do it manually my approach would be to pull up skyvector and look at major airports like Manchester, Portland, Albany, etc, and look for the nearest which is forecast to be above alternate minimums at my estimated time of arrival. But it would be awesome to have a flight planning tool that could tell me the airports nearest my intended destination that meet the alternate requirements. I did a quick google search but found nothing useful. Does such a tool exist?

Sounds like an idea to suggest for a future enhancement to Foreflight!

 

[poadeleted20]

But it would be awesome to have a flight planning tool that could tell me the airports nearest my intended destination that meet the alternate requirements. ... Does such a tool exist?

Not to my knowledge. Such a tool would require inputs on what approach systems you have and what approach category your aircraft is, and have access to a database of nonstandard alternate mins. Thus, it might be a bit more complicated than one might at first suspect.

 

[douglas393]

Not to my knowledge. Such a tool would require inputs on what approach systems you have and what approach category your aircraft is, and have access to a database of nonstandard alternate mins. Thus, it might be a bit more complicated than one might at first suspect.

In addition, it will need to know the conditions at the time of initiation of the flight plan, and the conditions forecasted at the alternatives at the time of arrival among other things. Futhermore, for some an alternative 10 or 15 miles away may be acceptable whereas others amy want an alternative 50 miles away. I see a lot of variables in such a program Not that it would be impossible to program, but to work correctly a lot of flexibility will need to be built in.

Doug

 

[dell30rb]

Not to my knowledge. Such a tool would require inputs on what approach systems you have and what approach category your aircraft is, and have access to a database of nonstandard alternate mins. Thus, it might be a bit more complicated than one might at first suspect.

And checking NOTAMS for those airports to make sure you don't have any approach systems out of service.

 

[Tom-D]

So, I'm just getting into the meat of my instrument training. We've discussed the alternate requirements. I won't be with my instructor until Saturday but I was at work looking out at KBED today (my work has a nice view of the airport!) in the soup and wondering if there are any good flight planning tools to select a legal alternate. Basically most of New England was IFR or LIFR and selection of an alternate would not be obvious. If forced to do it manually my approach would be to pull up skyvector and look at major airports like Manchester, Portland, Albany, etc, and look for the nearest which is forecast to be above alternate minimums at my estimated time of arrival. But it would be awesome to have a flight planning tool that could tell me the airports nearest my intended destination that meet the alternate requirements. I did a quick google search but found nothing useful. Does such a tool exist?

Yes a cell phone and the AOPA big book.

 

[spinfire]

OK, as a software engineer, I definitely recognize the challenges here! I was picturing something which gave a list of candidate alternates (check the NOTAMS yourself) but that still leaves plenty of complications. Even a tool which can show "airports within X mile radius with precision approaches" would be useful to narrow down the process.

If anyone has recommendations about the manual process they use to select alternates, I'd love to hear them.

 

[tonycondon]

If anyone has recommendations about the manual process they use to select alternates, I'd love to hear them.

i usually just pick the closest airport to my destination with an ILS

 

[Ghery]

A good suggestion from a King Schools video is to try and select an alternate that is between you and your destination. If things start getting worse you don't have to overfly your destination to get there. Not always an option, but something to keep in mind.

 

[poadeleted20]

A good suggestion from a King Schools video is to try and select an alternate that is between you and your destination. If things start getting worse you don't have to overfly your destination to get there. Not always an option, but something to keep in mind.

I do not follow the logic there. If you fly to your destination and miss, who cares whether the alternate is ahead of or behind you? If while en route, you choose not to continue the flight, you'll land at the best airport nearby, without regard to what your filed alternate is. And since the alternate is based on a lot of artificial constraints and weather data which may be 12 hours old or more by the time you get there, who cares what the filed alternate is when you realize you don't want to continue to, or can't get into, your original destination? You're going to choose the best diversion airport based on the situation at that time, not many hours ago when you were filing your flight plan.

The only real reason the FAA requires a filed alternate is to force you to carry enough gas to have some options. The filed alternate ceases to have any practical meaning once you take off. ATC doesn't know what it is, and doesn't care. If you miss at your destination, they're going to ask you to "say intentions," and will clear you based on the intentions you state, not on what you filed. If you lose comm and miss at your destination, they aren't going to expect you to go to that filed alternate and won't act on that basis.

 

[bluesky74656]

My instrument instructor told me about a flight from Cleveland to somewhere in the Philadelphia area where he had to list his alternate as St. Louis because that was the closest place with legal alternate requirements. He had to stop for fuel half way to keep it legal, but it worked.

 

[jhinman]

The only real reason the FAA requires a filed alternate is to force you to carry enough gas to have some options. The filed alternate ceases to have any practical meaning once you take off.

I thought the reason was for lost comms. Imagine you're nordo in the soup and your filed destination goes below minimums. What do you do?

I agree with everything else you said, though.

 

[poadeleted20]

I thought the reason was for lost comms. Imagine you're nordo in the soup and your filed destination goes below minimums. What do you do?

Whatever you think best under the circumstances based on the information you have at the time. Your filed alternate is irrelevant, and unknown to ATC anyway. Read 91.185 -- nothing there about missed approaches at all.

 

[flyingron]

Alternates only apply to filing flight plan and fuel requirements. As OtherRon points out, once you decide you can't get to your destination, wherever you want to go because the new destination (and it is not required to have been the filed alternate which as he says, ATC can't see without some effort).

In the NE, as someone else pointed out, you almost certainly are within fuel reserves of a major airport with an ILS (and I don't tend to go flying in weather that's forecast worse than 600-2).