Incorrect AWOS

Jay Honeck

Jay Honeck

Touchdown! Greaser!
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Jun 6, 2008
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Ingleside, TX
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Jay Honeck
We are based at KTFP (Ingleside, TX), and fly every few days.

We have noticed that our AWOS is consistently off by about 300' - 400', and not in a good way. When it is reporting "1300 broken", for example, we are usually in the bases at about 900'.

Is there a website or procedure for reporting this? It's been consistent for the last 4 months.
 
RotorAndWing said:
Airport manager
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How refreshingly old school. I've sent him an email.

With thousands of these reporting stations, I'm surprised to hear that there's no email, website or some central clearinghouse for reporting discrepancies like this?
 
That's how the chain is here, airport manager gets in contact with the AWOS maintenance folks. Then they re-pack rolls of $100 bills in the equipment until next time. :goofy:
 
Jay Honeck said:
How refreshingly old school. I've sent him an email.

With thousands of these reporting stations, I'm surprised to hear that there's no email, website or some central clearinghouse for reporting discrepancies like this?
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AWOS equipment is maintained by the local airport entity, isn't it?

I am not sure why you would envision some additional government(?) structure or bureaucracy be created and maintained for this function.

Maybe with new regulations requiring all airport managers to log into the clearing house daily as well to make certain someone hasn't reported an error with their AWOS vs walking into the airport office and telling them?

This would be no different than a central website for, say, hotel guests to report that the HVAC in their room is malfunctioning and smoking, eh?
 
Jay Honeck said:
With thousands of these reporting stations, I'm surprised to hear that there's no email, website or some central clearinghouse for reporting discrepancies like this?
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AWOSs are built at the request of the airport and usually with government funds dedicated to airport improvement projects. The airport as a whole(airport manager) is responsible for the maintenance and service of it. Not the FAA. AC-150/5220-16D has a whole list of criteria for accuracy of AWOSs. As others have stated it is best to just let the airport manager know that it is inaccurate. He may have a certified technician come test it or wait until its periodic maintenance is required.

Kinda like El Paso said, I'm not gonna call the Hilton 1-800 number if I need the AC fixed in my room :D.
 
DXR is another place that has the same sort of issues on a regular basis. It's a class "D", so we just tell the guys in the tower.
 
ElPaso Pilot said:
AWOS equipment is maintained by the local airport entity, isn't it?

I am not sure why you would envision some additional government(?) structure or bureaucracy be created and maintained for this function.

Maybe with new regulations requiring all airport managers to log into the clearing house daily as well to make certain someone hasn't reported an error with their AWOS vs walking into the airport office and telling them?

This would be no different than a central website for, say, hotel guests to report that the HVAC in their room is malfunctioning and smoking, eh?
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"Additional government structure"? I'm talking about a single page on the FAA website.

When I'm flying on a cross country flight, and notice a problem with one of the dozens of AWOS's along the way, I'm not going to look up the local airport manager's phone number. But if there were a central clearinghouse for reporting a discrepancy, I might take the time. This seems pretty easy, to me, but what do I know?

But whatever -- I've reported it to my buddy Paul, our top-notch new airport manager. I'm sure he will look into it.
 
I'm certified to inspect, calibrate and repair Allweather AWOS stations.

They are required to be inspected and calibrated 3 times a year and the inspection and calibration observed by an FAA inspector once a year. The airport has the freedom to sign a maintenance contract, get the work done on a per-call basis, or provide their own tech or use a freelance certified tech. If the AWOS station is not maintained to FAA standards, the FAA can and eventuall will decertify it and take it off the air.

As to your altimeter setting being wrong, Allweather AWOS uses two precision sensors and they have to agree by something like 5 feet else the altimeter data goes missing. So you're either using a non-Allweather AWOS and all bets are off, or someone has possibly configured the station with the wrong field elevation constant.

EDIT: Thanks. Ceilometer problem. They use a laser that fires a pulse straight up and measures backscatter reflection time as the beam goes through the cloud layers. No easy way to repair it in the field, will probably have to go back to the factory for repair and calibration.

As others have said, the airport manager is the first contact. If it's an Allweather AWOS, you can pm me with details and I can try to shake the tree a little bit.
 
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I read it as the cloud height measurement being inaccurate, not the altimeter setting. I know nothing of how these things work though.
 
StinkBug said:
I read it as the cloud height measurement being inaccurate, not the altimeter setting. I know nothing of how these things work though.
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Correct. The altimeter seems to be okay. It just seems to be measuring the cloud height incorrectly.
 
AWOS is inaccurate often and not just ceilings.

That's why at uncontrolled fields I'm constantly trying to confirm the winds reported with anything on the ground and finally the sock or tetrahedron.

It's happened more than once after arriving and looking at the sock I've had to reasses and re-announce that we're landing opposite of what we intended or on a different runway if it's a multiple runway drome.
 
txflyer said:
AWOS is inaccurate often and not just ceilings.
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Yes. I was flying into an airport one time that had a 6,000' x 100' main runway and a couple of grass crosswind runways. The AWOS was reporting a 25kt crosswind on the main runway. It was spring, so I called on the Unicom to ask the FBO what the condition of the sod was. "Oh, the AWOS has been screwed up for a couple of days!" was the answer. The 25kt crosswind was really on the sod. So the AWOS wind direction sensor was bad.

Even if I had missed looking at the sock (I am not as careful about that as I should be) I would have quickly figured it out on final. But I still wonder what might have happened if a student pilot came by and attempted to land on the grass runway that the AWOS would have led him to.
 
Graueradler said:
AWOS cloud heigths are AGL aren't they?
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And since they're based on a measurement at a solitary spot, may not always be useful. I was staying at the airport today and AWOS was reporting clear below 12,000. That may have been true in that one tiny spot. But overall it was more like 2500' broken.
 
I had a charter one time from Kotzebue to ambler. I called the awos for weather. It told me 10 miles visibility. So off we went.

About 20 miles out the vis started dropping. At 5 miles out it was down to 1 mile* and I had dropped down and was following the Kobuk river.

After I landed I asked the passenger what he had going in Ambler.

He told me he was there to fix the AWOS and that I was the only pilot that would go.....:hairraise::lol::lol:

*1 mile clear of clouds is all I needed to be legal
 
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