Alternates & METAR/SPECI
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Alternates & METAR/SPECI
Hi all,
1) I understand that you can't use a METAR for flight planning requirements. However, if a METAR or SPECI is issued en-route to your destination stating the weather is OVC below the Alternate Minima do you require an alternate which the TAF didn't previously require.
2) Also if the TAF during flight planning does not require an alternate or holding, do you require an alternate/holding if there is an amended TAF en-route stating weather is below alternate minima. Are you now required to divert en-route to carry the fuel for the alternate/holding requirement.
Thanks
newifr
1) I understand that you can't use a METAR for flight planning requirements. However, if a METAR or SPECI is issued en-route to your destination stating the weather is OVC below the Alternate Minima do you require an alternate which the TAF didn't previously require.
2) Also if the TAF during flight planning does not require an alternate or holding, do you require an alternate/holding if there is an amended TAF en-route stating weather is below alternate minima. Are you now required to divert en-route to carry the fuel for the alternate/holding requirement.
Thanks
newifr
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New IFR
1) yes
2)yes
As said above always use common sense and if in doubt carry the fuel. The boss may be angry though, but at least you will be alive to tell the tale, and he will still have his aircraft intact. A fair outcome me thinks!!
1) yes
2)yes
As said above always use common sense and if in doubt carry the fuel. The boss may be angry though, but at least you will be alive to tell the tale, and he will still have his aircraft intact. A fair outcome me thinks!!
METAR or TTF METAR ?
Be careful with the terminology.
A METAR is completely different to a TTF METAR.
A TTF METAR overrides a TAF. A METAR does not!
A METAR is merely an observation, with no trend attached, and the TAF is your main reference.
That said, if the TAF for your destination is good, and the METARS are trending down, you should be thinking about your options.
Based on your question:
1) NO
2) YES
A METAR is completely different to a TTF METAR.
A TTF METAR overrides a TAF. A METAR does not!
A METAR is merely an observation, with no trend attached, and the TAF is your main reference.
That said, if the TAF for your destination is good, and the METARS are trending down, you should be thinking about your options.
Based on your question:
1) NO
2) YES
I've had plenty of times where airservices australia has got the weather completely wrong
From the AIP:
So, if you receive an actual METAR reporting weather below the alternate minima, and the aerodrome isn't subject to the "continuous weather watch provided by TTF", and you are going to arrive within 30 mins of that METAR, you would be very hard pressed to convince a judge that you were operating with due care if you had to declare a fuel emergency to land below the minima ... 
58.2 Weather Conditions
58.2.1 Except when operating an aircraft under the VFR by day within 50NM of the point of departure, the pilot in command must provide for a suitable alternate aerodrome when arrival at the destination will be during the currency of, or up to 30 minutes prior to the fore- cast commencement of, the following weather conditions:
...
58.2.3 When weather conditions at the destination are forecast to be as specified at para 58.2.1, but are expected to improve at a specific time, provision for an alternate aerodrome need not be made if suf- ficient fuel is carried to allow the aircraft to hold until that specified time plus 30 minutes.
58.2.1 Except when operating an aircraft under the VFR by day within 50NM of the point of departure, the pilot in command must provide for a suitable alternate aerodrome when arrival at the destination will be during the currency of, or up to 30 minutes prior to the fore- cast commencement of, the following weather conditions:
...
58.2.3 When weather conditions at the destination are forecast to be as specified at para 58.2.1, but are expected to improve at a specific time, provision for an alternate aerodrome need not be made if suf- ficient fuel is carried to allow the aircraft to hold until that specified time plus 30 minutes.
APRuNe - Amatuer Pilots Rumour Network
CAR 257 (6) (b) states that you can only continue to a destination when conditions are below weather minimums if you are certain you will be able to gain visual reference to land on arrival.
I would say that if METARs(SPECI) were indicating that conditions were worsening below alternate minima and trending towards landing minima you would be losing your "reasonable grounds" if you then arrived and conditions were below landing minima. This is unless there was an inter or tempo or some other transient effect which could explain the conditions and you had fuel available to hold.
ENR 58 is mainly for planning purposes but also would most likely cover you for the reasonable check en-route as well.
(6) This regulation does not prevent a pilot from:
(a) making an approach for the purpose of landing at an aerodrome;
or
(b) continuing to fly towards an aerodrome of intended landing
specified in the flight plan;
if the pilot believes, on reasonable grounds, that the meteorological minima determined for that aerodrome will be at, or above, the meteorological minima determined for the aerodrome at the time of arrival at that aerodrome.
(a) making an approach for the purpose of landing at an aerodrome;
or
(b) continuing to fly towards an aerodrome of intended landing
specified in the flight plan;
if the pilot believes, on reasonable grounds, that the meteorological minima determined for that aerodrome will be at, or above, the meteorological minima determined for the aerodrome at the time of arrival at that aerodrome.
ENR 58 is mainly for planning purposes but also would most likely cover you for the reasonable check en-route as well.
Last edited by 43Inches; 11th Jul 2012 at 13:58.
And the Questions were....?
Answered by Capt Fathom......!
Drivel about Lawyers, Judges, Courts, reasonable grounds etc are all attempts to justify a PIC not making a COMMAND decision based on the RULES.
Common sense great, but for heaven's sake if you fly worrying about what the prosecution attorney is opening with at the trial then drive a taxi.
Jesus Wept!
Answered by Capt Fathom......!
Drivel about Lawyers, Judges, Courts, reasonable grounds etc are all attempts to justify a PIC not making a COMMAND decision based on the RULES.
Common sense great, but for heaven's sake if you fly worrying about what the prosecution attorney is opening with at the trial then drive a taxi.
Jesus Wept!
Last edited by ad-astra; 11th Jul 2012 at 22:39.
ad-astra, the question was posed as an in-flight scenario. Capt fathoms answer only applies to the minimum fuel required in a pre-flight fuel planning scenario. Once in flight if actual weather reports (METAR/SPECI/AWS) are stating weather below minimums then CAR 257 applies. Usually if unforcast conditions below minima occur a hazard alert will be issued followed by an ammended TAF some time later. If you happen to be the first one to observe these conditions then you have to make the decision without the assistance of forecast information. It is possible if you departed with minimum fuel you may have little time to decide to go to an alternate or return to departure point if you wait for amended information.
What you are saying is that based on Capt Fathoms response if a SPECI was issued stating low cloud and visibility at your destination but the current TAF indicated CAVOK you would continue with no allowance for a diversion if possible at the time.
It is exactly these situations that lead pilots to pressing on and hoping for the best rather than applying legal common sense.
I have had a few scenarios at different ports where AWS information en-route indicated low cloud, fog or mist forming not on the forecast. Firstly I informed FIS and asked for any amended TAFs, which on most occasion none was available, replaned fuel required for a diversion then usually shortly afterwards SPECI is issued and 5-10 minutes later the met guys would issue an amended TAF. All these events occured on commercial revenue flights and in some cases a diversion was needed and safe landing at an alternate carried out.
What you are saying is that based on Capt Fathoms response if a SPECI was issued stating low cloud and visibility at your destination but the current TAF indicated CAVOK you would continue with no allowance for a diversion if possible at the time.
It is exactly these situations that lead pilots to pressing on and hoping for the best rather than applying legal common sense.
I have had a few scenarios at different ports where AWS information en-route indicated low cloud, fog or mist forming not on the forecast. Firstly I informed FIS and asked for any amended TAFs, which on most occasion none was available, replaned fuel required for a diversion then usually shortly afterwards SPECI is issued and 5-10 minutes later the met guys would issue an amended TAF. All these events occured on commercial revenue flights and in some cases a diversion was needed and safe landing at an alternate carried out.
Last edited by 43Inches; 11th Jul 2012 at 23:46.
Once again I will quote Capt Fathom...
No
Common sense and airmanship will dictate otherwise!
Be careful with the terminology
Based on your question:
1) NO
2) YES
1) NO
2) YES
do you require an alternate which the TAF didn't previously require
Common sense and airmanship will dictate otherwise!
The AIP is a compliance document not a regulation, ENR-58 is a preflight planning document. If you were top of descent with your airfield in sight (clear with CAVOK METAR) and an amended TAF was issued saying you now require an alternate due fog would you divert if you only had just enough fuel to do so at this point?
CAR 257 is the actual regulation, it does not apply particularly to planning stage it is an in-flight control the same as the rules for collision avoidance. The CAR does not refer to the forecast or observed just the simple wording that if conditions are below minimum you may not proceed there (unless item (6) is assured).
If you are flying towards Caerbannog on minimum reserves and the AWS conditions suddenly indicate below minimum weather and look down and see that Castle Anthrax is CAVOK with fuel and lodging available. Why not land?
CAR 257 is the actual regulation, it does not apply particularly to planning stage it is an in-flight control the same as the rules for collision avoidance. The CAR does not refer to the forecast or observed just the simple wording that if conditions are below minimum you may not proceed there (unless item (6) is assured).
If you are flying towards Caerbannog on minimum reserves and the AWS conditions suddenly indicate below minimum weather and look down and see that Castle Anthrax is CAVOK with fuel and lodging available. Why not land?
Last edited by 43Inches; 12th Jul 2012 at 00:25.
Don't fly me anywhere IFR, OK
Last edited by Aimpoint; 12th Jul 2012 at 00:26.
43Inches, the metar in the OP is not below minimums though, it is only below the alternate minima which is for use when planning, and it is just a metar. So no, you don't require alternate fuel, but it should be a cue for you to have a think about your options.
Last edited by AerocatS2A; 12th Jul 2012 at 00:31.
Aerocat I have not refered to alternate minima throughout my posts, just minima. Its really becomes a pilot decision en-route with regard to whether you can land safely or not on arrival. If you can not be certain that this is possible than a diversion to somewhere you can be certain should be considered and held as a backup plan.
My point is for en-route considerations the TAF or any forecast is someones educated theory on the anticipated weather, the METAR/SPECI/AWS/Pilot Observations Etc... are the actual weather conditions.
If the SPECI was below landing minima yet TAF indicated CAVOK would the answer be different?
A further point to consider is if another IFR aircraft ahead of you reports that they only just got visual with low cloud and reduced visibilty, the TAF and METARs all indicate CAVOK, what then?
My point is for en-route considerations the TAF or any forecast is someones educated theory on the anticipated weather, the METAR/SPECI/AWS/Pilot Observations Etc... are the actual weather conditions.
If the SPECI was below landing minima yet TAF indicated CAVOK would the answer be different?
A further point to consider is if another IFR aircraft ahead of you reports that they only just got visual with low cloud and reduced visibilty, the TAF and METARs all indicate CAVOK, what then?
Last edited by 43Inches; 12th Jul 2012 at 01:06.
You didn't, but the question in the original post refers to alternate minima. The CAR you reference refers to minimums for landing which is not alternate minima but landing minima. So your use of the CAR doesn't address the question in the OP. It comes down to the difference between what you are required to do and what would be a good idea. If a metar has weather below alternate mins and the TAF is ok, there is no requirement to pick up some more fuel, but it might be a good idea to, or it might not, it's really just an indication that you should investigate further.
The CAR states unless you are reasonably certain that weather will be above approach minimum at your time of arrival. If the trend on the METARs indicate that it will not be certain then you are starting to get into dangerous territory. AIP ENR 58 is clear cut from a planning perspective, obviously you can not use point observations to remove requirements but they can be used to asssess whether the forecast is accurate. If the accuracy of the forecast is in doubt it can't be used until such time as this ambiguity is removed.
You have to use your brain to assess from observations in flight whether or not you will have landing minima on arrival. In preflight the alternate minima is designed as a buffer to allow for deteriorations below this level not to affect your fuel integrity on arrival. Depending on how far away from a destination you are and your fuel status then how you treat SPECI or Hazard alerts will be different.
If you ignored a SPECI that was between landing and alternate minima, continued and conditions went below landing minima on your arrival and you had to declare an emergency you would be ruled under CAR 257. Especially if at the time of the initial observations you had sufficient fuel to divert to an suitable alternate it would be an interesting case.
You have to use your brain to assess from observations in flight whether or not you will have landing minima on arrival. In preflight the alternate minima is designed as a buffer to allow for deteriorations below this level not to affect your fuel integrity on arrival. Depending on how far away from a destination you are and your fuel status then how you treat SPECI or Hazard alerts will be different.
If you ignored a SPECI that was between landing and alternate minima, continued and conditions went below landing minima on your arrival and you had to declare an emergency you would be ruled under CAR 257. Especially if at the time of the initial observations you had sufficient fuel to divert to an suitable alternate it would be an interesting case.