A confession

cowman

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Cowman
Today I conducted VFR operations both from and to an airport with an ASOS reporting a visibility of 1.5miles. Below is a picture representative of the actual field conditions.

2403773A-153C-48FD-91F2-9E013E1742F4.jpeg

Joking aside, is there any regulatory or generally good reason for not just ignoring an obviously wrong automated weather report? If I had filed IFR on the return trip for some reason and it still said 1.5mi visibility would I still be required to file an alternate? Would approaches where that was below minimums become unavailable?

I mean I'm sure any reasonable pilot is just going to go visual. But since is this is POA let's be the best kind of correct- technically correct.
 
You don’t need any specific conditions to fly an approach… you can do it in 0/0… just can’t land. Landing is all about actual conditions, not reported ones.

I’ve landed VFR at a class D that was technically IFR (overcast 800 or so), but was just a cloud layer on top of the center of the field and almost CAVU at the approach end of the runway in use. I came in VFR and they gave me pattern entry instructions. That was the piece that actually surprised me - I was ready for them to deny me and me having to request SVFR.
 
Funny, I did the same thing not long ago. Here's hoping that we both don't get busted.
(My prepared defense in case I get called on it is that the temp/dewpoint spread was 20/16)
 
Today I conducted VFR operations both from and to an airport with an ASOS reporting a visibility of 1.5miles. Below is a picture representative of the actual field conditions.

View attachment 110687

Joking aside, is there any regulatory or generally good reason for not just ignoring an obviously wrong automated weather report? If I had filed IFR on the return trip for some reason and it still said 1.5mi visibility would I still be required to file an alternate? Would approaches where that was below minimums become unavailable?

I mean I'm sure any reasonable pilot is just going to go visual. But since is this is POA let's be the best kind of correct- technically correct.
Regulatory speaking, some operations are dictated by Reported Surface Visibility, some are not. They are dictated by Flight Visibility. At what airport did this happen?
 
In my experience, most automated WX systems are horribly inaccurate and most of the time are totally unreliable. I listen to them for the altimeter setting and proceed as planned. Flame away!
 
You don’t need any specific conditions to fly an approach… you can do it in 0/0… just can’t land. Landing is all about actual conditions, not reported ones.

I’ve landed VFR at a class D that was technically IFR (overcast 800 or so), but was just a cloud layer on top of the center of the field and almost CAVU at the approach end of the runway in use. I came in VFR and they gave me pattern entry instructions. That was the piece that actually surprised me - I was ready for them to deny me and me having to request SVFR.
What may have happened is Controllers can use the latest observation immediately for aircraft operations. They don't have to wait for the METAR be issued or ATIS cut
 
Reminds me of the day I departed Sacramento in practically unflyable conditions and when I called to get a clearance to "on top," they advised me the weather was Ceiling indefinite, Sky partially obscured, visibility three miles, smoke and haze.

It was VFR! Coulda fooled me...
 
Reminds me of the day I departed Sacramento in practically unflyable conditions and when I called to get a clearance to "on top," they advised me the weather was Ceiling indefinite, Sky partially obscured, visibility three miles, smoke and haze.

It was VFR! Coulda fooled me...
I assume you got a climb to OTP anyway?
 
I've been advised that destination weather was below VFR when I could clearly see the airport and surrounding area from 15 miles away. Since approach can't suggest it, you have to remember to request SVFR. They may give you the hint, though, with "what are your intentions?".
 
If they are reporting IMC but you can see the airport from 15 miles away you don't need to ask for SVFR, you tell them you see the airport and you want to land if it's controlled, or just go and land if it's uncontrolled.
 
Fly the airplane based on what you see, weather changes quickly. ATIS does not.
 
I was once "stuck" at an airport where the end of the RW nearest the coast (where the awos is) was fogged in, but everywhere inland, including 85% of the RW was clear. Not knowing any better (I had about 75 hours then) I waited until the fog rolled out.

My current understanding is that at an uncontrolled field, it's up to the pilots discretion. The awos controls what controllers can do, but is just advisory for pilots. If you cause a problem however, be sure the record of the awos will be presented as evidence against you.

With regards to filing, you always need an alternate unless the forecast for the time of arrival is above MVFR. When you get there and you can see the field, just report the field in sight and take the visual, or cancel for cookies.

Unless you're flying part 121, determining if flight visibility is good enough to land is on the pilot. I'm not sure if awos is controlling for the rare times an airliner lands at an uncontrolled field.
 
If they are reporting IMC but you can see the airport from 15 miles away you don't need to ask for SVFR, you tell them you see the airport and you want to land if it's controlled, or just go and land if it's uncontrolled.
I don’t know if that’s always true. The incident I mentioned was at BTV (Burlington VT) where there are trainees, who I believe are told to go by the reported weather station info regardless of what they see out the window, but if I get time later I’ll try to look it up.
 
One time in Alaska flying a 207 I was outside the Class E airspace and the AWOS was reporting 1/2 mile visibility. I called the on field flight service to request SVFR. I was told the surface visibility is 1/2 mile, remain outside the Class E surface area. I told FS I would be holding over a VFR reporting point to wait out the visibility.

Official talk over, the FS guy called me by name and said the weather observer is taking an observation as we speak. A minute later he came back with ''visibilty in the Class E is now observed as 1 mile (the magic mile) state your intentions. I requested SVFR and got clearance. Just as soon as I finished repeating SVFR instructions and reported my position, the director of operations reported in and requested SVFR. FS responded with ''visibility in the Class E surface area is now 1/2 mile, state intentions.''

Since he was in a Piper 1040 he just went to center and requested a pop up clearance for the ILS. I knew I was going to get it once he was on the ground, and I did. He was wanting to know why I was flying a 207 in 1/2 mile visibility. My response....''I don't get paid unless I am flying.''

The visibility was not 1/2 mile. I saw the runway a good 1/4 out...
 
I don’t know if that’s always true. The incident I mentioned was at BTV (Burlington VT) where there are trainees, who I believe are told to go by the reported weather station info regardless of what they see out the window, but if I get time later I’ll try to look it up.
If you can, find out if the Controllers there are LAWRS certified?
 
I don’t know if that’s always true. The incident I mentioned was at BTV (Burlington VT) where there are trainees, who I believe are told to go by the reported weather station info regardless of what they see out the window, but if I get time later I’ll try to look it up.

That's pretty crappy if that's what they do.
 
I don’t know if that’s always true. The incident I mentioned was at BTV (Burlington VT) where there are trainees, who I believe are told to go by the reported weather station info regardless of what they see out the window, but if I get time later I’ll try to look it up.
Trainees or not, if they aren’t certified observers, they can’t override the official report.
 
Flips off the radio.

There, now I can land at an uncontrolled field when the station is reporting imc when it’s Vmc.

if I can fly nordo in vmc, I can land at an uncontrolled field in vmc regardless of what the station says.
 
If they are reporting IMC but you can see the airport from 15 miles away you don't need to ask for SVFR, you tell them you see the airport and you want to land if it's controlled, or just go and land if it's uncontrolled.
Even if you are cleared to land, you are responsible for complying with the rules applicable to your flight, VFR or SVFR.

91.155(d) and 91.157(c) are written the same way for VFR and SVFR, respectively, and in both cases you can only operate based on flight visibility "if ground visibility is not reported." If the airport reports less than 3 miles ground visibility, you can't operate VFR within the airspace regardless of a landing clearance. If it reports less than 1 mile ground visibility, then you can't operate SVFR there.

7110.65 section 7-5-7 has a note that says: "Clear an aircraft to land at an airport with an operating control tower, traffic permitting, if the pilot reports the airport in sight. The pilot is responsible to continue to the airport or exit the surface area. 14 CFR Section 91.157 prohibits VFR aircraft (other than helicopters) from landing at any airport within a surface area when ground visibility is less than 1 mile."

My read on this is that you can't just ignore the reported weather if the airport is in controlled airspace (including a Class E surface area).
 
Even if you are cleared to land, you are responsible for complying with the rules applicable to your flight, VFR or SVFR.

91.155(d) and 91.157(c) are written the same way for VFR and SVFR, respectively, and in both cases you can only operate based on flight visibility "if ground visibility is not reported." If the airport reports less than 3 miles ground visibility, you can't operate VFR within the airspace regardless of a landing clearance. If it reports less than 1 mile ground visibility, then you can't operate SVFR there.

7110.65 section 7-5-7 has a note that says: "Clear an aircraft to land at an airport with an operating control tower, traffic permitting, if the pilot reports the airport in sight. The pilot is responsible to continue to the airport or exit the surface area. 14 CFR Section 91.157 prohibits VFR aircraft (other than helicopters) from landing at any airport within a surface area when ground visibility is less than 1 mile."

My read on this is that you can't just ignore the reported weather if the airport is in controlled airspace (including a Class E surface area).
So you can’t fly nordo at class e airports?
 
So you can’t fly nordo at class e airports?
That's not what I said. I was responding to the claim that you can always land VFR at an airport with reported IMC if you can see the airport. I pointed out the regulations that say otherwise.

That being said, you can't fly NORDO at a Class E airport when it's reporting less than 3 miles visibility or a ceiling under 1,000 feet, because you need a radio to get SVFR clearance.
 
That's not what I said. I was responding to the claim that you can always land VFR at an airport with reported IMC if you can see the airport. I pointed out the regulations that say otherwise.

That being said, you can't fly NORDO at a Class E airport when it's reporting less than 3 miles visibility or a ceiling under 1,000 feet, because you need a radio to get SVFR clearance.
How can you know it's not reporting vis > 3 miles when you don't have a radio and it's sunny as far as you can see?
 
How can you know it's not reporting vis > 3 miles when you don't have a radio and it's sunny as far as you can see?
You can accidentally look at the AWOS display in the FBO or hear it on their base station radio. I admit, that's a rookie mistake and I never should have done such a foolish thing. (In my case, the ceiling was 800 feet and my eyeballs agreed it was a lowish overcast. Not exactly the clear skies scenario described here. But it's legally indistinguishable as far as I can see. Get it, as far as I can see?)
 
What class of airspace was the airport in?
@cowman ? This matters. What airport? Surface Area or not? If so, D or E? Primary or Satellite Airport?

Run of the mill class E uncontrolled field, no shelf and not near any B C or D. If you want to pull it up on a chart it's KUIN. BTW this is NOT the first time my eyeballs and this field's ASOS have disagreed. I might not trust my eyes on cloud height but when I can see clearly from one end of the field to another... and the cornfields beyond from the ground and have clear view of the field from over 20 miles out, I will absolutely trust my eye judgement over the ASOS.


Even if you are cleared to land, you are responsible for complying with the rules applicable to your flight, VFR or SVFR.

91.155(d) and 91.157(c) are written the same way for VFR and SVFR, respectively, and in both cases you can only operate based on flight visibility "if ground visibility is not reported." If the airport reports less than 3 miles ground visibility, you can't operate VFR within the airspace regardless of a landing clearance. If it reports less than 1 mile ground visibility, then you can't operate SVFR there.

7110.65 section 7-5-7 has a note that says: "Clear an aircraft to land at an airport with an operating control tower, traffic permitting, if the pilot reports the airport in sight. The pilot is responsible to continue to the airport or exit the surface area. 14 CFR Section 91.157 prohibits VFR aircraft (other than helicopters) from landing at any airport within a surface area when ground visibility is less than 1 mile."

My read on this is that you can't just ignore the reported weather if the airport is in controlled airspace (including a Class E surface area).

In my specific case I actually made a mental note to look, I was > 20 miles from the airport and clearly able to see the entire field. ASOS was still reporting 1.5 haze at that time. It was late afternoon, the airport had a similar report earlier that day. Actual conditions were clearly sky clear and unlimited visibility all day, all other airports across the area were reporting sky clear and vis > 6 or vis 10miles and had been all day. The photo above was taken immediately after landing. There was absolutely zero chance whatsoever of that report being correct. There is some major construction work being done on the field and a whole slew of NOTAMs regarding that. Nothing about the ASOS, they did mention a wind direction indicator being out of service but I'm pretty sure that means the big metal airplane wind indicator not the ASOS. My wild guess is dust from construction work was clouding the sensor but that's pure speculation.
 
Run of the mill class E uncontrolled field, no shelf and not near any B C or D. If you want to pull it up on a chart it's KUIN. BTW this is NOT the first time my eyeballs and this field's ASOS have disagreed. I might not trust my eyes on cloud height but when I can see clearly from one end of the field to another... and the cornfields beyond from the ground and have clear view of the field from over 20 miles out, I will absolutely trust my eye judgement over the ASOS.




In my specific case I actually made a mental note to look, I was > 20 miles from the airport and clearly able to see the entire field. ASOS was still reporting 1.5 haze at that time. It was late afternoon, the airport had a similar report earlier that day. Actual conditions were clearly sky clear and unlimited visibility all day, all other airports across the area were reporting sky clear and vis > 6 or vis 10miles and had been all day. The photo above was taken immediately after landing. There was absolutely zero chance whatsoever of that report being correct. There is some major construction work being done on the field and a whole slew of NOTAMs regarding that. Nothing about the ASOS, they did mention a wind direction indicator being out of service but I'm pretty sure that means the big metal airplane wind indicator not the ASOS. My wild guess is dust from construction work was clouding the sensor but that's pure speculation.
What was the temperature/dew-point spread?
 
I've been advised that destination weather was below VFR when I could clearly see the airport and surrounding area from 15 miles away. Since approach can't suggest it, you have to remember to request SVFR. They may give you the hint, though, with "what are your intentions?".

A friend said he was once asked "is there anything special we can do for you?"
 
I was trying to get out of a delta to jump to an airport 7 miles away and the sky that direction was clear, but above the station there was a cloud. The controller said "I can't clear you for takeoff. There are things you can do to get out, but I can't suggest them to you. What would you like to do?"
 
I was trying to get out of a delta to jump to an airport 7 miles away and the sky that direction was clear, but above the station there was a cloud. The controller said "I can't clear you for takeoff. There are things you can do to get out, but I can't suggest them to you. What would you like to do?"

A friend said he was once asked "is there anything special we can do for you?"

Don't you wonder how many pilots don't get it when that happens?

I know several that scratch their heads when presented with that scenario.
 
Run of the mill class E uncontrolled field, no shelf and not near any B C or D. If you want to pull it up on a chart it's KUIN. BTW this is NOT the first time my eyeballs and this field's ASOS have disagreed. I might not trust my eyes on cloud height but when I can see clearly from one end of the field to another... and the cornfields beyond from the ground and have clear view of the field from over 20 miles out, I will absolutely trust my eye judgement over the ASOS.
Since you want the “technically correct” answer…straight from 91.155:

(d) Except as provided in § 91.157 of this part, no person may take off or land an aircraft, or enter the traffic pattern of an airport, under VFR, within the lateral boundaries of the surface areas of Class B, Class C, Class D, or Class E airspace designated for an airport -

(1) Unless ground visibility at that airport is at least 3 statute miles; or

(2) If ground visibility is not reported at that airport, unless flight visibility during landing or takeoff, or while operating in the traffic pattern is at least 3 statute miles.

So flight vis can’t fly override reported vis, even if reported vis is wrong.

Having said that, have you ****ed anyone off lately who would report you?
 
Since you want the “technically correct” answer…straight from 91.155:

(d) Except as provided in § 91.157 of this part, no person may take off or land an aircraft, or enter the traffic pattern of an airport, under VFR, within the lateral boundaries of the surface areas of Class B, Class C, Class D, or Class E airspace designated for an airport -

(1) Unless ground visibility at that airport is at least 3 statute miles; or

(2) If ground visibility is not reported at that airport, unless flight visibility during landing or takeoff, or while operating in the traffic pattern is at least 3 statute miles.

So flight vis can’t fly override reported vis, even if reported vis is wrong.

Having said that, have you ****ed anyone off lately who would report you?

I'm a poor FAR lawyer but this part doesn't say anything about "reporting" or ASOS. It just says that ground visibility is at least 3 statute miles and doesn't specify how I determine that. I would argue I can determine that visually. I would further argue that since pireps are a thing, a pilot can self-report visibility.
(1) Unless ground visibility at that airport is at least 3 statute miles; or
I would say that if we can determine somehow that the visibility *IS* at least 3 statute miles we're legal and need not proceed to 2. Unless we need to start asking questions about what is meant by "is" :D

But, for fun... the second part sounds like it only applies to airports where where no reporting is available
(2) If ground visibility is not reported at that airport, unless flight visibility during landing or takeoff, or while operating in the traffic pattern is at least 3 statute miles.
However, again we have that word "is" without any reference to how we determine that state of being. Which certainly at the very least implies pilots are able to make such judgements themselves.
 
I'm a poor FAR lawyer but this part doesn't say anything about "reporting" or ASOS. It just says that ground visibility is at least 3 statute miles and doesn't specify how I determine that. I would argue I can determine that visually. I would further argue that since pireps are a thing, a pilot can self-report visibility.
(1) Unless ground visibility at that airport is at least 3 statute miles; or
I would say that if we can determine somehow that the visibility *IS* at least 3 statute miles we're legal and need not proceed to 2. Unless we need to start asking questions about what is meant by "is" :D

But, for fun... the second part sounds like it only applies to airports where where no reporting is available
(2) If ground visibility is not reported at that airport, unless flight visibility during landing or takeoff, or while operating in the traffic pattern is at least 3 statute miles.
However, again we have that word "is" without any reference to how we determine that state of being. Which certainly at the very least implies pilots are able to make such judgements themselves.
No, you’re a really ****ty FAR lawyer. ;) Ya gotta read ‘em to be just poor.
Ground visibility means prevailing horizontal visibility near the earth's surface as reported by the United States National Weather Service or an accredited observer.
 
Hol' up. Does this mean if the fog is so thick that I can't see the taxiway in front of my prop but the ASOS says "sky clear visibility 6 miles" I'm good to go? There has to be some provision for cases where the weather station is clearly reporting incorrectly.
 
Hol' up. Does this mean if the fog is so thick that I can't see the taxiway in front of my prop but the ASOS says "sky clear visibility 6 miles" I'm good to go? There has to be some provision for cases where the weather station is clearly reporting incorrectly.
There is. You report it to airport management, and they either get it fixed or NOTAM it OTS.
 
This seems incredibly silly to me, especially as Salty noted it's entirely legal to fly nordo. That said, this is from flying magazine:

Food for thought regarding AWOS/ASOS weather reports: The following is an excerpt from an FAA legal interpretation dated May 24, 2012, concerning VFR flight visibility reported by automated weather stations.

“You describe a scenario where a pilot on a VFR flight plan arrives at an uncontrolled airport in Class E airspace to the surface and picks up the AWOS information for that airport. The AWOS report states that there is a ceiling of 100 feet and visibility is one-fourth mile with calm winds. You further explain that the pilot flies over the airport and determines that there is a fog bank over one end of the runway which obscures the last 1,000 feet but the other 9,000 feet are clear.

“You asked whether a pilot in this scenario is in violation of §91.155 if he lands at the airport.

Yes, if the pilot lands at the airport in the scenario described above, he is in violation of §91.155. In order for a pilot to land an aircraft or enter the traffic pattern of an airport, ground visibility at the airport must be at least 3 statute miles. See 14 CFR §91.155(d). The AWOS is reported a ceiling of 100 feet and visibility of one-fourth mile. This clearly does not meet the visibility requirements as outlined in § 91.155. The pilot’s report of flight conditions cannot supersede the AWOS in this scenario. The determination of the visibility by a pilot is not an official weather report or an official ground visibility report.”

I would argue that that scenario is different though as part of the runway is obscured.
 
Another wrinkle:
We all treat AWOS & ASOS the same (or at least I do), but I believe there is a legal difference in that the NWS has ownership in the ASOS systems and they are considered more accurate.

Also @cowman if there's construction on the airport, there a high probability that some dust from that activity had settled on the sensor and it needs cleaned. It's probably worth a call to airport ops/manager, particularly if it's doing it consistently.
 
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