A confession

Jim K said:
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.
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The scenario is different, but the reg is the same, as would be the interpretation.
 
dbahn said:
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?".
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PaulS said:
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.
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My post above was poorly worded and was clarified later. It occurred at a class C airspace (KBTV) where the weather station was reporting IFR conditions but airspace all around it was excellent VFR. As long as the reported visibility was at least one mile, they could authorize but not suggest SVFR. Different scenarios apply in class E and G airspace.
 
Jim K said:
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.
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Wait, so if it's CAVU at the station and the first 500 feet of runway and 0/0 thereafter, it's legal to land???????
 
MauleSkinner said:
Per 91.155, yes, but 91.13 would probably kick in at some point.
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Once the wheels touch the ground, you're no longer flying... so do any weather mins apply at that point?
 
kaiser said:
Once the wheels touch the ground, you're no longer flying... so do any weather mins apply at that point?
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"No longer flying" covers you for 91.13 (a), but then there's still (b).
 
cowman said:
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.
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Correct me if I’m wrong but the requirement to file an alternate is based on forecast weather, not actual at the time of planning or departure. And the visibility requirement is flight visibility, so that’s your call as PIC.
 
At our home airport, the ASOS sometimes reports erroneous low vis or ceilings. I think most of the time it is due to spider webs over the sensor or other things like that. Maybe a call to unicom on the radio or phone would add credence to your decision to land or takeoff despite the ASOS.
 
Jim K said:
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.
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I always wondered why they don't simplify the 123 rule into "If +/- 1 hour of ETA your destination is not VFR, then file alternative"
 
mryan75 said:
Correct me if I’m wrong but the requirement to file an alternate is based on forecast weather, not actual at the time of planning or departure. And the visibility requirement is flight visibility, so that’s your call as PIC.
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I’ll let you read the reg(s) and correct yourself…might stick a little better. :)
 
This convo brings to mind the location of the sensors on the airport. I know at KAAA - Logan County the AWOS is a fair bit from the runway and obscured by buildings which I have to believe has effect on the wind reporting. That was often a hot topic when hangar flying.
 
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