Releasing an Aircraft IFR on a METAR?

4EngineETOPS

Well-Known Member
We have a policy against doing that. Unless you can show the Government TAF is unavailable or unreliable, we can’t get a RAMTAF..or “shop for a legal forecast”. There was a time we’d call the weather god Kavoris and he’d always give us mins for dispatch. Placed who like to use the 24 hour tempo tend to get this treatment (I’m looking at you former Soviet Union).



What do you do if the TAF amends on flight? Same same.
Same "weather shopping" policy for us. The only time I would even consider dispatching using a METAR would be if a trend of METARs over several hours significantly disproved the TAF. In that case, I'd order an EWINS TAF and compare that to all other relevant data.
 

DispatcherSam

NOTAMed OTS
My first airline used to have an exemption for this in addition to 3585 or whatever you confounded kids are calling it these days. The other exemption was only really good for flights less than 45 mins long
 

A1TAPE

Well-Known Member
What do you mean by "weather shopping"? I've heard of the term "helicoptor shopping" in the HEMS industry. That's when a hospital will call for a helo but get turned down due to wx THEN call another helicopter service but not tell the crew that they were already denied by the first helicopter due to wx.
 

bbmikej

Well-Known Member
What do you mean by "weather shopping"? I've heard of the term "helicoptor shopping" in the HEMS industry. That's when a hospital will call for a helo but get turned down due to wx THEN call another helicopter service but not tell the crew that they were already denied by the first helicopter due to wx.
It's essentially when you have weather that is right around mins but the TAF is illegal but generally correct so you call either NWS, WSI or another source of forecasts and hint that you want a forecast that is legal. Even if you don't think the weather will actually be above mins when you get there.
 

A1TAPE

Well-Known Member
It's essentially when you have weather that is right around mins but the TAF is illegal but generally correct so you call either NWS, WSI or another source of forecasts and hint that you want a forecast that is legal. Even if you don't think the weather will actually be above mins when you get there.
Is this ever looked down upon by the FAA or examined as a possible accident cause by the NTSB should one occur? A good example would be lets say you have an airport where they are reporting winds that exceed the limits of the aircraft. The better forecast you request deletes the winds. The aircraft overruns the runway on landings. Would the NTSB say that had the enhanced forecast played a role leading up to the accident?
 

bbmikej

Well-Known Member
Is this ever looked down upon by the FAA or examined as a possible accident cause by the NTSB should one occur? A good example would be lets say you have an airport where they are reporting winds that exceed the limits of the aircraft. The better forecast you request deletes the winds. The aircraft overruns the runway on landings. Would the NTSB say that had the enhanced forecast played a role leading up to the accident?
Absolutely. You would have to have a good answer for why you wanted a second opinion. On the other hand however, if a forecast says an airport will be 1/4sm for the next 5 or 6 hours and the vis has been increasing and has been at over a mile for a bit, it is perfectly ok to call and ask them to take a look at it.
 

who'swho

Don't hesitate. Penetrate!
Is this ever looked down upon by the FAA or examined as a possible accident cause by the NTSB should one occur? A good example would be lets say you have an airport where they are reporting winds that exceed the limits of the aircraft. The better forecast you request deletes the winds. The aircraft overruns the runway on landings. Would the NTSB say that had the enhanced forecast played a role leading up to the accident?
Winds are irrelevant when deciding whether it's legal for dispatch or not, beyond carrying a wind alternate. You dispatch off visibility.
 

A1TAPE

Well-Known Member
Winds are irrelevant when deciding whether it's legal for dispatch or not, beyond carrying a wind alternate. You dispatch off visibility.
But if the reported winds would be outside the aircraft limitations such as a tailwind, then you couldn't release the aircraft.
 

IJD

Well-Known Member
But if the reported winds would be outside the aircraft limitations such as a tailwind, then you couldn't release the aircraft.
I have never heard of getting a Ram TAF for winds.Just visibility. It usually happens at out stations that don't get ammended TAFs. The TAF is showing a quarter mile but the metar is showing 2SM, you call and get one, and then hopefully in about 15 minutes you have a legal TAF to dispatch too.
 

McCrosky

Well-Known Member
What do you mean by "weather shopping"? I've heard of the term "helicoptor shopping" in the HEMS industry. That's when a hospital will call for a helo but get turned down due to wx THEN call another helicopter service but not tell the crew that they were already denied by the first helicopter due to wx.
For example., a previous job we would have a flight to an airport in the Stan’s. The local Weather service TAF had a 1/4SM for our arrival time, so, we had access to the Air Force weather service and could get their forecast. It also had 1/4SM. So then we’d call Kavoris and mention that we need a forecast for CrapHole Craptastistan and somehow drop and hint a 1/2SM would be nice to have. And as if by magic, we had a legal forecast. And away we went. I only remember a couple times where we actually had to divert.

But if the reported winds would be outside the aircraft limitations such as a tailwind, then you couldn't release the aircraft.
FAR 121.195(e) says you can.
 

who'swho

Don't hesitate. Penetrate!
But if the reported winds would be outside the aircraft limitations such as a tailwind, then you couldn't release the aircraft.
What's the point of a WIND alternate? All you need for dispatch is visibility. That's it. Have you gotten your license yet? Obviously NOT.
 

who'swho

Don't hesitate. Penetrate!
121.195(e) says you need one.
I think you misunderstood me. That's what I was saying. Just because winds are forecasted to be beyond what we need for landing (i.e. crosswinds forecast beyond limits at a single runway airport) doesn't mean you can't dispatch it. I wouldn't bother getting an EWINS forecast in that situation. But yes, you would need a wind alternate if winds are forecasted to be out of limits. A1 was saying you can't release if the winds are forecasted out of limits.
 

4EngineETOPS

Well-Known Member
But if the reported winds would be outside the aircraft limitations such as a tailwind, then you couldn't release the aircraft.
Crosswinds are often not considered to be AFM limitations in certain circumstances, depending on the manufacturer. The listed maximum crosswind on a dry runway, for example, is not limiting for many aircraft.
 

A1TAPE

Well-Known Member
Winds are irrelevant when deciding whether it's legal for dispatch or not, beyond carrying a wind alternate. You dispatch off visibility.
I get that all operators are different in terms of their criteria for a legal dispatch. This excerpt was from a NWA Airlink flight that crashed in traverse city, MO years back. Emphasis mine.

National Weather Service (NWS) forecast was for sustained winds of 18 knots with gusts to 30 knots. This forecast, exceeding a 10-knot tailwind sustained component, would mean no dispatch to Traverse City and no use of ILS runway 28, the only precision approach. A VOR approach to runway 10 was not usable because minimums were too high. Visibility was okay.
He spoke with the Northwest meteorology office and they issued a revised forecast. They have the ability to amend forecasts. The revised forecast by the Northwest office was for no gusts.
 

who'swho

Don't hesitate. Penetrate!
I get that all operators are different in terms of their criteria for a legal dispatch. This excerpt was from a NWA Airlink flight that crashed in traverse city, MO years back. Emphasis mine.

National Weather Service (NWS) forecast was for sustained winds of 18 knots with gusts to 30 knots. This forecast, exceeding a 10-knot tailwind sustained component, would mean no dispatch to Traverse City and no use of ILS runway 28, the only precision approach. A VOR approach to runway 10 was not usable because minimums were too high. Visibility was okay.
He spoke with the Northwest meteorology office and they issued a revised forecast. They have the ability to amend forecasts. The revised forecast by the Northwest office was for no gusts.
Whoever wrote whatever article you are referencing was wrong. I'm guessing they probably never dispatched a flight. Whether you can dispatch a flight or not depends on visibility. Whether you can shoot the approach... different story. Dispatching into crappy weather with an alternate allows you to at least go take a look.
 
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