91.169 question

azure

azure

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azure
A question for all FAR gurus out there: if your destination is forecast to be at least 2000/3 for 1 hour before and 1 hour after your ETA, and one or more SIAPs are "defined" by Part 97 for the airport, it seems that 91.169 does not require a filed alternate even if those SIAPs are all NA. Is this correct? I haven't checked out what it means for an SIAP to be "defined" under Part 97, and maybe the devil is in those details. It just seems to be closer to the spirit of the regs that if there are no available approaches at the destination, then for all practical purposes it should be treated as not having any approaches, thereby requiring an alternate regardless of forecast weather. Yet a literal reading of 91.169 seems to say that as long as there is a published approach, NA or no, whether an alternate is needed depends only on the 1-2-3 rule.

The reason I ask is that now that both approaches into my home field are NA at night, I wonder if I need to file an alternate for my home leg if coming back at night IFR, even if the forecast is for CAVU.
 
azure said:
The reason I ask is that now that both approaches into my home field are NA at night, I wonder if I need to file an alternate for my home leg if coming back at night IFR, even if the forecast is for CAVU.
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Interesting question. I file home to a private airport with no approaches all the time. No alternate is identified if VMC is forecast. Assuming that's okay, I'd say no.
 
Frankly for both the primary airport and the alternate, I consider approaches I can not fly (either because they are NA or I do not have the equipment to fly them) as not existing.

MauleDriver, you are wrong. No matter how great the weather is, if the destination doesn't have an approach, you MUST declare an alternate. Now if the weather is VFR up to the enroute altitudes, you can pick an airport without approaches as an alternate.
 
Generally speaking, if you ask people in Flight Standards, they'll tell you to mentally insert the phrase "that I can fly with the equipment I have" in that rule. IOW, unless you have all the necessary gear for that approach in your plane, you consider it not to exist. And frankly, while I don't know if anyone's asked the Chief Counsel about it, it wouldn't make much sense otherwise. So, if the only approach at your destination is the "NDB RWY 22," and you don't have an ADF, for that flight, it is as though your destination has no approach at all and you must have an alternate.

One other point is that in figuring the need for and selection of alternates, a non-WAAS (i.e., TSO c129) GPS like a KLN-94 (as opposed to a WAAS TSO c146 GNS-430W) is also considered non-existant since it is only "supplemental" and not "sole source" certified. So, if the only approach at your destination is the "NDB or GPS RWY 22," and you don't have an ADF or WAAS GPS, for that flight, it is as though your destination has no approach at all.


Finally, FRon is correct about David being wrong. If you read the reg carefully, you'll see that an alternate is always required unless:
  1. There is an approach to fly, and
  2. You have the 1-2-3 weather (or the helo alternative for fling wingers).
Sec. 91.169

IFR flight plan: Information required.

(a) Information required. Unless otherwise authorized by ATC, each person filing an IFR flight plan must include in it the following information:
(1) Information required under Sec. 91.153 (a) of this part;
(2) Except as provided in paragraph (b) of this section, an alternate airport.
(b) Paragraph (a)(2) of this section does not apply if :
(1) Part 97 of this chapter prescribes a standard instrument approach procedure to, or a special instrument approach procedure has been issued by the Administrator to the operator for, the first airport of intended landing; and
(2) Appropriate weather reports or weather forecasts, or a combination of them, indicate the following:
(i) For aircraft other than helicopters. For at least 1 hour before and for 1 hour after the estimated time of arrival, the ceiling will be at least 2,000 feet above the airport elevation and the visibility will be at least 3 statute miles.
(ii) For helicopters. At the estimated time of arrival and for 1 hour after the estimated time of arrival, the ceiling will be at least 1,000 feet above the airport elevation, or at least 400 feet above the lowest applicable approach minima, whichever is higher, and the visibility will be at least 2 statute miles.
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Regulations aside, I never look at an alternate as anything other than a filing exercise. Enroute I check the weather at all of the airports around my destination using XM, look the radar, look at the approaches/lighting/facilities, talk to ATC, think about ground transportation, etc, all before I get there. That way if I really need an alternate I've already worked it out, that might even include diverting well prior to my destination if a large area is under bad weather. I'm just not a believer in filing the closest legal airport as an alternate and leaving it at that.
 
Ron Levy said:
One other point is that in figuring the need for and selection of alternates, a non-WAAS (i.e., TSO c129) GPS like a KLN-94 (as opposed to a WAAS TSO c146 GNS-430W) is also considered non-existant since it is only "supplemental" and not "sole source" certified. So, if the only approach at your destination is the "NDB or GPS RWY 22," and you don't have an ADF or WAAS GPS, for that flight, it is as though your destination has no approach at all.
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So by that logic, in the days before WAAS, you ALWAYS had to file an alternate if the only approach to your destination airport was GPS?

I never read it that way or operated that way I'm still not sure that's correct. I always read it to mean that for overlay approaches and enroute nav on airways that you had to have the "other" (NDB or VOR) equipment in the airplane if you had a C129 GPS.
 
flyingron said:
Frankly for both the primary airport and the alternate, I consider approaches I can not fly (either because they are NA or I do not have the equipment to fly them) as not existing.
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Yes, exactly what I was thinking. Just wondering why it wasn't spelled out in the reg.

I was planning to fly to JXN this afternoon for dinner and then back home, both IFR just to get experience in the system even though the weather is forecast to be good VFR. So I will have to file an alternate on the return leg. Now the forecast turns iffy around 00Z and if the system speeds up, there's a small chance I'll actually need the alternate (KPTK) to have an approach to fly to get down to pattern altitude, then return home VFR. Worst case, I might have to leave to plane at KPTK, but the probability seems very low at the moment. (I am really not sure what the MVA is near KVLL, and thus don't know whether they could give me a letdown below a 2000' ceiling if needed and then let me land visually.)

So much new to learn and think about now being "cloud licensed"! Thanks guys.
 
Ron Levy said:
One other point is that in figuring the need for and selection of alternates, a non-WAAS (i.e., TSO c129) GPS like a KLN-94 (as opposed to a WAAS TSO c146 GNS-430W) is also considered non-existant since it is only "supplemental" and not "sole source" certified. So, if the only approach at your destination is the "NDB or GPS RWY 22," and you don't have an ADF or WAAS GPS, for that flight, it is as though your destination has no approach at all.
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So by that logic, in the days before WAAS, you ALWAYS had to file an alternate if the only approach to your destination airport was GPS?

I never read it that way or operated that way, and I'm still not sure that's correct. I always read it to mean that for overlay approaches and enroute nav on airways that you had to have the "other" (NDB or VOR) equipment in the airplane if you had a C129 GPS.

So a "VOR or GPS 29 approach" wouldn't "exist" unless you had the VOR equipment in the airplane too, but a "GPS 29" approach was valid with a C129 GPS.
 
Alexb2000 said:
Regulations aside, I never look at an alternate as anything other than a filing exercise. Enroute I check the weather at all of the airports around my destination using XM, look the radar, look at the approaches/lighting/facilities, talk to ATC, think about ground transportation, etc, all before I get there. That way if I really need an alternate I've already worked it out, that might even include diverting well prior to my destination if a large area is under bad weather. I'm just not a believer in filing the closest legal airport as an alternate and leaving it at that.
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I think that's what most of us do, but keep in mind the reason for choosing it in advance is so ATC knows what to expect in the event of lost comm. In that case you've hopefully chosen an alternate you can legally fly.
 
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LDJones said:
I think that's what most of us do, but keep in mind the reason for choosing it in advance is so ATC knows what to expect in the event of lost comm. In that case you've hopefully chosen an alternate you can legally fly.
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Good point.
 
LDJones said:
I think that's what most of us do, but keep in mind the reason for choosing it in advance is so ATC knows what to expect in the event of lost comm. In that case you've hopefully chosen an alternate you can legally fly.
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ATC doesn't know your alternate until you miss at your destination and request clearance to KABC, or such.

It you are lost comm the provisions of 91.185 end when you begin the missed approach at your destination. It is emergency authority at the point.
 
Alexb2000 said:
Regulations aside, I never look at an alternate as anything other than a filing exercise. Enroute I check the weather at all of the airports around my destination using XM, look the radar, look at the approaches/lighting/facilities, talk to ATC, think about ground transportation, etc, all before I get there. That way if I really need an alternate I've already worked it out, that might even include diverting well prior to my destination if a large area is under bad weather. I'm just not a believer in filing the closest legal airport as an alternate and leaving it at that.
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That's a good point. In this case if there's ANY chance at all that KPTK will be below mins when I get there, I just won't launch. But the weather is coming from the south, and there are at least two airports north of KPTK that are within range and have precision approaches.

In fact, if there's any evidence of the system speeding up before I set out, I'll scrub. I don't want to get stuck at JXN.
 
LDJones said:
I think that's what most of us do, but keep in mind the reason for choosing it in advance is so ATC knows what to expect in the event of lost comm. In that case you've hopefully chosen an alternate you can legally fly.
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IMO, that may be the "letter of the law" but in many cases it's simply not practical. Often the "best" alternates are the nearest airport with an ILS that works for the expected wind direction but that also often happens to be a major airline hub (MSP as an alternate for SGS is a good example) and the LAST thing ATC wants to happen if you go nordo on your way to KFCM is to go missed at SGS and then proceed nordo to MSP just because that's what you filed for an alternate. Even if you put FCM as the alternate you'd be cutting through some rather busy airspace if you followed the nordo rules to the letter.
 
gismo said:
IMO, that may be the "letter of the law" but in many cases it's simply not practical. Often the "best" alternates are the nearest airport with an ILS that works for the expected wind direction but that also often happens to be a major airline hub (MSP as an alternate for SGS is a good example) and the LAST thing ATC wants to happen if you go nordo on your way to KFCM is to go missed at SGS and then proceed nordo to MSP just because that's what you filed for an alternate. Even if you put FCM as the alternate you'd be cutting through some rather busy airspace if you followed the nordo rules to the letter.
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Are you suggesting that the pilot not file an airline airport as the alternate, or are you suggesting that in a lost comm situation the pilot not fly to the airline airport he filed as the alternate?

If, as Wally suggests, the filed alternate is meaningless in a lost comm situation, then what the hell is the point of filing it in the first place? If you HAVE comms, you can tell ATC where you want to go after going missed at the destination.
 
TMetzinger said:
So by that logic, in the days before WAAS, you ALWAYS had to file an alternate if the only approach to your destination airport was GPS?
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No I believe what he was saying is a non-WAAS pilot can't consider GPS approaches at ALTERNATE airports. At least that is my understanding of the regs though it's hazy because I put a 480 in my plane. If you have a non-WAAS gps your alternate needs to be something you can fly without GPS such as a VOR or ILS
 
azure said:
That's a good point. In this case if there's ANY chance at all that KPTK will be below mins when I get there, I just won't launch. But the weather is coming from the south, and there are at least two airports north of KPTK that are within range and have precision approaches.

In fact, if there's any evidence of the system speeding up before I set out, I'll scrub. I don't want to get stuck at JXN.
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Sounds like you have a plan (made from the ground), excellent deal.

One other point about alternates, I believe a lot of pilots select an alternate based primarily on fuel. If you need destination +alternate +45. Then they try to find an airport within 5-10 minutes so they can be legal with 1 hour fuel remaining. Of course if the destination goes below an airport 5 minutes away is probably below also. Flying around busy airspace in DFW I hear a lot of minimum fuel calls and stressed voices when the area goes below. Just another reason I am a believer in early enroute checking.
 
The primary goal of the alternate is to compute the fuel requirements. If an alternate is required (either via weather or no SIAP), then you've got to plan enough fuel to get to a suitable (by the regs) alternate in addition to your 45 minute reserve.

This isn't a big issue here in the east where we have more airports than you can shake a stick at. I always file IAD or CLT on my runs back and forth from CJR to NC26. They're only 35 miles away from the destination, have big runways, nice ILSs, bright approach lights, and ground transportation. Out in the middle of the country sometimes finding a field suitable for an alternate is elusive and you may not have fuel for that.

As pointed out, once you've planned the fuel and filed the thing. It's moot. If I can't get into my destination (or it looks like I might not), I start looking around for a suitable airport with weather that I can get into. It may be a lot closer than my filed alternate.
Once you abandon your initial destination, where you go next is your new destination. It need not be your filed alternate and it can even be NA for filing as an alternate.
 
flyingron said:
No I believe what he was saying is a non-WAAS pilot can't consider GPS approaches at ALTERNATE airports. At least that is my understanding of the regs though it's hazy because I put a 480 in my plane. If you have a non-WAAS gps your alternate needs to be something you can fly without GPS such as a VOR or ILS
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That's what I thought too.
 
flyingron said:
The primary goal of the alternate is to compute the fuel requirements. If an alternate is required (either via weather or no SIAP), then you've got to plan enough fuel to get to a suitable (by the regs) alternate in addition to your 45 minute reserve.

This isn't a big issue here in the east where we have more airports than you can shake a stick at. I always file IAD or CLT on my runs back and forth from CJR to NC26. They're only 35 miles away from the destination, have big runways, nice ILSs, bright approach lights, and ground transportation. Out in the middle of the country sometimes finding a field suitable for an alternate is elusive and you may not have fuel for that.

As pointed out, once you've planned the fuel and filed the thing. It's moot. If I can't get into my destination (or it looks like I might not), I start looking around for a suitable airport with weather that I can get into. It may be a lot closer than my filed alternate.
Once you abandon your initial destination, where you go next is your new destination. It need not be your filed alternate and it can even be NA for filing as an alternate.
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I get the requirement to PLAN for alternatives... I just don't get the requirements to FILE an alternate airport if ATC doesn't pay any attention to it anyway.
 
TMetzinger said:
Are you suggesting that the pilot not file an airline airport as the alternate, or are you suggesting that in a lost comm situation the pilot not fly to the airline airport he filed as the alternate?

If, as Wally suggests, the filed alternate is meaningless in a lost comm situation, then what the hell is the point of filing it in the first place? If you HAVE comms, you can tell ATC where you want to go after going missed at the destination.
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I'm suggesting that a pilot fly to whatever airport makes the most sense given the situation if he goes nordo. The lost comm regulations were written for a different era (non-radar) and for the most part simply don't make sense today. The real purpose of the alternate filing requirements are to make it fairly likely you can go missed at your filed destination and get to an airport where you can successfully complete an approach and land without running out of fuel on the way.
 
TMetzinger said:
So by that logic, in the days before WAAS, you ALWAYS had to file an alternate if the only approach to your destination airport was GPS?

I never read it that way or operated that way, and I'm still not sure that's correct. I always read it to mean that for overlay approaches and enroute nav on airways that you had to have the "other" (NDB or VOR) equipment in the airplane if you had a C129 GPS.

So a "VOR or GPS 29 approach" wouldn't "exist" unless you had the VOR equipment in the airplane too, but a "GPS 29" approach was valid with a C129 GPS.
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With a TSO C129a GPS, you may file to an airport that only has a GPS approach but must have an alternate that has no dependency on a GPS. In regards to the selecting of an alternate, in effect you can consider that the GPS has been removed from your aircraft and the selected approach procedure has no dependency on the GPS and can be flown with the remaining navigation equipment. For example, this excludes an ILS that requires a DME or ADF and you are not so equipped and would depend on using the GPS in lieu of the DME or ADF.

The majority of the WAAS GPS installations don't have this limitation, but some still do if they are at earlier software revisions and have the limitation in their AFMS.
 
John Collins said:
With a TSO C129a GPS, you may file to an airport that only has a GPS approach but must have an alternate that has no dependency on a GPS. In regards to the selecting of an alternate, in effect you can consider that the GPS has been removed from your aircraft and the selected approach procedure has no dependency on the GPS and can be flown with the remaining navigation equipment. For example, this excludes an ILS that requires a DME or ADF and you are not so equipped and would depend on using the GPS in lieu of the DME or ADF.

The majority of the WAAS GPS installations don't have this limitation, but some still do if they are at earlier software revisions and have the limitation in their AFMS.
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John, are you saying that one must file for an alternate even if the weather doesn't require it, just because it's a GPS-only airport and you've got a C129 GPS?
 
aterpster said:
ATC doesn't know your alternate until you miss at your destination and request clearance to KABC, or such.

It you are lost comm the provisions of 91.185 end when you begin the missed approach at your destination. It is emergency authority at the point.
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:yes: ATC has no clue what your alternate is. The alternate has nothing to do with lost commo. SQK 7600 and go missed for another approach or go to your alternate. ATC will clear the way. This thread seems familiar.
 
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How can they clear the way if they don't know where you're going?
 
I've attended two ATC Rainchecks at different centers at which the "alternate is only for lost comm" philosophy was emphasized. No matter what the regs say, center wants your butt on the ground and out of their airspace ASAP if they can't talk to you.
 
TMetzinger said:
John, are you saying that one must file for an alternate even if the weather doesn't require it, just because it's a GPS-only airport and you've got a C129 GPS?
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AFaIK, the weather is still an issue but the requirement is the same as for an IFR destination with no approach, i.e. that it must be good enough to make it to the ground in VMC from the lowest IFR altitude available (e.g. MEA, MOCA, MVA, etc) to eliminate the need for an approach.

Edit: upon further reflection I think this is probably wrong WRT the situation where your intended destination has a GPS approach you can use with your non-WAAS navigator. YMMV.
 
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Jaybird180 said:
How can they clear the way if they don't know where you're going?
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They call FSS on the landline and find out their alternate. Then they protect the airspace IAW the altitude and route in 91.185. What I'm getting at is the purpose of the alternate is a flight planning requirement if you can't get into your destination. As Arterpster said this alternate isn't known to ATC unless the pilot tells them. If you're missed and lost commo your operating in emergency territory. You don't even have a clearance to the alternate. As a former controller I'd expect them to go to their alternate but if they chose to land at an airport along the way because it's VMC, they can.
 
So honesty check:

If I lose coms, I'll go to my clearance airport as I should. Shoot an approach. If I don't get in and fuel has now become a concern (say 1 hour) I am not going direct to my alternate if the reported weather is similar and I have the option of going the other direction to find higher ceilings and a sure landing. Yes, they will be moving people out of the way and most likely very unhappy with me. Hopefully when they see me at the IAF of a better weather airport flying the published approach they will understand my intentions and get everyone out of the way.

I might lose my ticket but in that circumstance I'll do whatever I can to protect my passengers and get on the ground safely.
 
TMetzinger said:
I get the requirement to PLAN for alternatives... I just don't get the requirements to FILE an alternate airport if ATC doesn't pay any attention to it anyway.
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ATC doesn't know what your airplane color or how much fuel you have, but you're required to file them.
 
Correct, the people who say it is for lost comms are wrong. ATC has to guard against you doing just about everything. Yeah, if you are in the soup, you have rules about where you are going. But if you are in VMC you're likely to bail to a practicable VFR field or may end up having other emergencies that may get you off the filed/cleared routing.
Frankly, I think it's wishful thinking that a pilot without comms will go to the destination, miss, go tot he alternate, and then what? Fly around for 45 minutes until he runs out of fuel?
 
John Collins said:
No. I was just discussing the alternate filing requirements.
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OK - Ron seemed to say that you couldn't file to a GPS-only airport without filing an alternate too if your GPS was C129, even if the weather (1-2-3 rule) didn't require an alternate. Of that I'm not (yet) convinced.

I fully agree that IF you need to file an alternate and you only have a C129 GPS on board, the alternate needs to have non-GPS approaches that you can fly. You can still shoot the GPS approach when you get there, though.
 
TMetzinger said:
OK - Ron seemed to say that you couldn't file to a GPS-only airport without filing an alternate too if your GPS was C129, even if the weather (1-2-3 rule) didn't require an alternate. Of that I'm not (yet) convinced.

I fully agree that IF you need to file an alternate and you only have a C129 GPS on board, the alternate needs to have non-GPS approaches that you can fly. You can still shoot the GPS approach when you get there, though.
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I think Ron was suggesting if all the SIAP's at a destination airport were known to be NA at the time of arrival, for example NA at night, then the airport would be treated the same as if the airport did not have a part 97 SIAP during night time and therefore the 1-2-3 exception wouldn't apply. That is a reasonable position to take, but it is arguable that the regulation doesn't cover this case the way it is written. I think the intent of the regulation was to assure that regardless the weather forecast, an instrument procedure that could be flown, either at the destination or if none were available at the destination, then an alternate, would always be part of the flightplan. This way it covers filing to an airport under IFR to an airport without a Part 97 SIAP, if the weather ends up being worse than forecast.

The other hole in the regulations is that the forecast may be better than the required 1-2-3 but still be below the minimums required for the approach.
 
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TMetzinger said:
So by that logic, in the days before WAAS, you ALWAYS had to file an alternate if the only approach to your destination airport was GPS?
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Correct.

I never read it that way or operated that way I'm still not sure that's correct. I always read it to mean that for overlay approaches and enroute nav on airways that you had to have the "other" (NDB or VOR) equipment in the airplane if you had a C129 GPS.
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Read the relevant AC's and the flight manual for your system, and the definition of "supplemental navigation system" in those documents.
 
gismo said:
IMO, that may be the "letter of the law"
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It's not. The one and only one reason for requiring alternates is to force pilots to carry enough fuel to have options. History tells us that if you don't, there will be shortsighted individuals launching with minimum fuel who will be running out of gas left, right, and center, thus ruining the safety record and creating headaches for controllers.
 
Go to a raincheck and listen to ATC's opinion. Why would the alternate matter if communication were possible, especially when a high percentage of the filings are throw-away entries anyway?

flyingron said:
Correct, the people who say it is for lost comms are wrong. ATC has to guard against you doing just about everything. Yeah, if you are in the soup, you have rules about where you are going. But if you are in VMC you're likely to bail to a practicable VFR field or may end up having other emergencies that may get you off the filed/cleared routing.
Frankly, I think it's wishful thinking that a pilot without comms will go to the destination, miss, go tot he alternate, and then what? Fly around for 45 minutes until he runs out of fuel?
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flyingron said:
No I believe what he was saying is a non-WAAS pilot can't consider GPS approaches at ALTERNATE airports.
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You can't consider them at either destination or alternate. The issue is that since the non-WAAS GPS is only a supplemental nav system, you must have an alternate means of IFR navigation to your destination. If the only approach there is GPS, you don't have an alternate means to get there, and you need an alternate airport.
 
TMetzinger said:
I get the requirement to PLAN for alternatives... I just don't get the requirements to FILE an alternate airport if ATC doesn't pay any attention to it anyway.
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Filing isn't the issue as much as having the fuel, but filing is proof of the planning.
 
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