Filing an Alternate?
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roncachamp
Final Approach
1 2 3 rule. 1 hr before your ETA and 1 hour after your ETA, the weather at your destination has to be at least a 2000 foot ceiling and 3 miles vis or you have to file an alternate.
hindsight2020
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hindsight2020
600/2 precision 800/2 non-precision at the alternate in order to qualify
Ok, got all that but if I am filing my destination that has an ILS, my alternate is required then to have something else, like a gps approach, correct? Or if I file my destination that has only gps approach, my alternate would be required to have a VOR or ILS?
gismo
Touchdown! Greaser!
Combining all that, to be legal you must list an alternate if the wx at your destination is forecast to be less than 3 mi vis and 2000 AGL ceiling within an hour of your ETA. If that requires an alternate the listed alternate's forecast at the ETA for the alternate (i.e. ETA for the dest plus time to fly an approach then divert to the alternate) must be at least 600/1 if the alternate has a precision approach (ILS), 800/2 if it has a non-precision approach, and good enough to descend from the MEA to the airport with "basic VFR" conditions if there is no approach at the alternate.
If you have a GPS installation approved for "sole source" navigation (i.e. most WAAS units with appropriate software and antenna) you can list an airport that only has GPS approaches using the non-precision wx criteria (800/1), if your GPS is not sole source you cannot use such an airport as your required alternate. Also any approach marked "NA for alternate" for the appropriate time (e.g. many ILSs are NA for alternate at night) cannot be considered when determining if an airport is a viable filed alternate. Finally, you cannot consider any approach for which your airplane is not equipped to fly (e.g. NDB w/o ADF, RNAV-GPS w/o approach approved GPS and current or verified DB, or VOR w/o required VOR accuracy check).
Also you cannot use airports with only GPS approaches for both your destination and your alternate.
But that's just to be legal and mostly about flight/fuel planning. Though not required by FAR (other than the careless/reckless rule) you should also consider the following:
1) Wind. If the forecast wind would make landing straight in from the only ILS approach, use the NP (800/1) wx requirement. And if the forecast wind is close to your personal xwind limits for all usable runways from any viable approach choose a different alternate airport.
2) Circle to land issues. If it appears possible that a CTL approach would be needed consider increasing the required visibility to 3-5 miles (or more at night) especially if you aren't real familiar with the airport.
3) Unusually high published minumums. 800/2 isn't going to work if the published mins for the approach needed to land at the alternate are 1000/3. Consider adding a buffer to the published mins so your ace in the hole doesn't become a joker.
4) Big, high traffic airports make tempting alternate choices but also usually require significant extra fuel because when the wx is down you'll likely be #42 in line for an approach. Better to stick with lower traffic, medium sized airports (e.g. Class C and below) if you need a precision approach.
If you have a GPS installation approved for "sole source" navigation (i.e. most WAAS units with appropriate software and antenna) you can list an airport that only has GPS approaches using the non-precision wx criteria (800/1), if your GPS is not sole source you cannot use such an airport as your required alternate. Also any approach marked "NA for alternate" for the appropriate time (e.g. many ILSs are NA for alternate at night) cannot be considered when determining if an airport is a viable filed alternate. Finally, you cannot consider any approach for which your airplane is not equipped to fly (e.g. NDB w/o ADF, RNAV-GPS w/o approach approved GPS and current or verified DB, or VOR w/o required VOR accuracy check).
Also you cannot use airports with only GPS approaches for both your destination and your alternate.
But that's just to be legal and mostly about flight/fuel planning. Though not required by FAR (other than the careless/reckless rule) you should also consider the following:
1) Wind. If the forecast wind would make landing straight in from the only ILS approach, use the NP (800/1) wx requirement. And if the forecast wind is close to your personal xwind limits for all usable runways from any viable approach choose a different alternate airport.
2) Circle to land issues. If it appears possible that a CTL approach would be needed consider increasing the required visibility to 3-5 miles (or more at night) especially if you aren't real familiar with the airport.
3) Unusually high published minumums. 800/2 isn't going to work if the published mins for the approach needed to land at the alternate are 1000/3. Consider adding a buffer to the published mins so your ace in the hole doesn't become a joker.
4) Big, high traffic airports make tempting alternate choices but also usually require significant extra fuel because when the wx is down you'll likely be #42 in line for an approach. Better to stick with lower traffic, medium sized airports (e.g. Class C and below) if you need a precision approach.
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Since the rule says to always file an alternate except when..., I just take the easy way and always file an alternate.
azure
Final Approach
As long as you always depart with full tanks, that won't affect your legal range, but it does mean you need to account for your filed alternate in fuel planning (which is AFAIK the main reason for the alternate requirements anyway).
Yes, I make sure I have at least an hour more reserve than is required anyway, so I could do that too. I just don't see the point to ALWAYS filing an alternate.
Lance, did I misread or did you mean 600/2 and 800/2 for the standard alternate minimums? Or have the standard alt mins been relaxed recently?
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gismo
Touchdown! Greaser!
Not a bad policy. More often than not, when the wx at your destination is good enough to not require an alternate, finding an alternate that has adequate wx is easy. Conversely, when qualified alternates are hard to find, you are very likely to be required to find one.
gismo
Touchdown! Greaser!
You didn't misread, I mistyped. It's still 600/2 and 800/2 for precision and non-precision standard alternate mins. I corrected that and also edited in a couple omissions.
Concerning alternate airport flight planning when using WAAS and Non-WAAS GPS equipment, you might want to read the following. It's a recent policy satement from the FAA in the form of a NOTAM issued April 2013. This might be old news to some of you, but was new to me.
http://www.faa.gov/air_traffic/publications/notices/2013-09-19/GEN13000.htm
It basically says that pilots who use IFR-certified non-WAAS GPS equipment can now flight plan for the use of a GPS-based IAP at either the destination or the alternate airport, but not at both. The previous policy allowed non-WAAS users to plan for a GPS-based IAP at their destination but not at their alternate airport. I think WAAS-equipped aircraft alternate filing procedures are the same as before. Also, some new stuff on baro-VNAV equipped aircraft planning procedures.
FYI
http://www.faa.gov/air_traffic/publications/notices/2013-09-19/GEN13000.htm
It basically says that pilots who use IFR-certified non-WAAS GPS equipment can now flight plan for the use of a GPS-based IAP at either the destination or the alternate airport, but not at both. The previous policy allowed non-WAAS users to plan for a GPS-based IAP at their destination but not at their alternate airport. I think WAAS-equipped aircraft alternate filing procedures are the same as before. Also, some new stuff on baro-VNAV equipped aircraft planning procedures.
FYI
I'm basically lazy. So far, anyway, I have found it just as easy to file an alternate as not file one.
But what's this "need full tanks" thing? Tabs gives me over 4 hours of fuel on board (if I really screw up the leaning and use the worst burn rate the airplane is capable of), more than enough for my 3 hour bladder.
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Note if the destination doesn't have a published approach, you must ALWAYS file an alternate no matter what the weather is forecast to be.
Note you don't have to necessarily have to have an approach at the alternate. You only need to a forecast that enables you to get down from the enroute structure VFR. Don't forget to check for non-standard alternate (and alternate n/a).
Note you don't have to necessarily have to have an approach at the alternate. You only need to a forecast that enables you to get down from the enroute structure VFR. Don't forget to check for non-standard alternate (and alternate n/a).
azure
Final Approach
Yes, and that's also true if the destination airport has an approach but you can't fly it for some reason. Whenever I file a return flight home at night, I have to file an alternate even in CAVU weather because the only available approach into my home field is noted "procedure NA at night".
poadeleted20
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Close -- you missed one thing: 1 2 3 rule. 1 hr before your ETA and 1 hour after your ETA, the weather at your destination has to be at least a 2000 foot ceiling and 3 miles vis and your destination must have an SIAP you can fly or you have to file an alternate.
poadeleted20
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...or as published if not "standard." You'll know this because that SIAP will have a triangle-A symbol in the remarks section near the top. See the front part of the Terminal Procedures book to see that the actual alternate mins are for that approach.
poadeleted20
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No. Generally, you can file an alternate that is based on the same system you plan to use at the destination. The exception is c129 ("non-WAAS") GPS aircraft, which cannot use a GPS-required approach for their alternate if they need their GPS to fly the approach at their destination. Only aircraft with c146 ("WAAS") GPS's can file an alternate which relies on GPS if they need their GPS to fly the approach at their destination.
In your case, with the c129 Garmin 300XL, your alternate cannot be based on use of your GPS unless you have an approach you can fly without it at your destination. So, for example, if you need GPS for the approach at your destination, and you need an alternate, if you don't have a DME receiver on board, you cannot file Easton MD (KESN) as an alternate even based on the ILS 4 approach (the other four are all RNAV(GPS) and thus out on their face), since that approach is DME REQUIRED, and you need your GPS to sub for the DME to fly it legally. However, if you can fly an approach at your destination without that GPS, then thanks to that April 2013 NOTAM, you can file ESN as your alternate.
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And with that, TMBG's "Particle Man" is playing over and over in my head....thanks, Ron.
Thread creep: in whatever EFB app or planning website you use, how does it handle IFR alternates?
For example, while FltPlan.com gives you a list of suggested alternates, that's only based on proximity and not on whether it has standard or alternate minimums (or even, I think, is listed as "Alternate NA").
For example, while FltPlan.com gives you a list of suggested alternates, that's only based on proximity and not on whether it has standard or alternate minimums (or even, I think, is listed as "Alternate NA").
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Old fashioned way so far, look at the alternate airport plates and look up non-standard alternate mins if needed.
Captain
Final Approach
I love how fltplan.com lists DCA as the top alternate for IAD. We've had a couple pilots select it too. Face palm...
EppyGA
Touchdown! Greaser!
Just curious what difference it makes since ATC doesn't see it anyway?
It doesn't make any different to ATC, but you better not try to go there. Further, the whole point of an alternate is really PREFLIGHT planning to make sure you have:
1. A reasonable alternative if the weather is below mins at the destination.
2. Enough fuel to make it at least that far (with reserves).
If you flightplan DCA as your alternate to IAD and you ned up needing to go to BWI you may not quite have enough fuel.
EppyGA
Touchdown! Greaser!
I understand all of that. my only points was ATC doesn't know what you put down as an alternate.
EppyGA
Touchdown! Greaser!
What are you gonna do Captain since ATC still doesn't know what your alternate is?
roncachamp
Final Approach
They have no need for it.
And I was answering the question that you asked as to what difference it makes. I didn't realize that it was a rhetorical question just stuck in there to introduce extraneous material into the record.
poadeleted20
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The FAA is on record that in an emergency, you can fly through the FRZ and land at DCA if that's what you have to do to terminate the flight safely. Happened to someone with a lightening strike in flight a couple of years ago, and the FAA praised the pilot for handling it well and bringing the flight to a safe conclusion.
poadeleted20
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One supposes they could call FSS and get them to dig it out, but that's not in ATC's book. If you lose comms and then miss at your destination, the regulations and the controller's handbook are silent -- you're entirely on your own to decide how to bring the flight to a safe conclusion per 14 CFR 91.3(b). ATC will essentially just watch you on radar and try to clear out everyone below/in front of you.
Captain
Final Approach
Well riddle me this;
What's the point of fileing the alternate then? I know the base reason is fuel planning, but I mean after you determine a legal alternate and put enough gas on the plane what's the point of actually fileing it? If ATC can't see it what's the point.
Along those lines, say I make a last minute change to my alternate. Like, in the plane taxiing out to the runway I notice my alternate weather isn't legal and call the company and get another alt that is legal. Gas is good, new alt is good, alls well but the wrong airport code is on file. Would I need to cancel the clearance I already got and file a new plan with the correct alternate? Seems like who cares. If there was a later investigation on that flight I could show the inspector my legal alternate and show enough gas onboard to do it so I'm good to go, right?
What's the point of fileing the alternate then? I know the base reason is fuel planning, but I mean after you determine a legal alternate and put enough gas on the plane what's the point of actually fileing it? If ATC can't see it what's the point.
Along those lines, say I make a last minute change to my alternate. Like, in the plane taxiing out to the runway I notice my alternate weather isn't legal and call the company and get another alt that is legal. Gas is good, new alt is good, alls well but the wrong airport code is on file. Would I need to cancel the clearance I already got and file a new plan with the correct alternate? Seems like who cares. If there was a later investigation on that flight I could show the inspector my legal alternate and show enough gas onboard to do it so I'm good to go, right?
azure
Final Approach
It's there on record and the FAA can pull it up during the post-accident investigation. Helps to rule out inadequate fuel planning, in theory anyway.
That happened to me during my last training flight in actual, just before my checkride. New TAF came out between the time I filed and when I picked up my clearance. I asked my CFII if I needed to refile and he said don't worry, you were legal at the time of filing and you have enough fuel to get to any number of legal alternates. Not worth the trouble to call FSS to refile.