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-   -   IFR Alternate Question (https://www.pprune.org/pacific-general-aviation-questions/454894-ifr-alternate-question.html)

MyNameIsIs 18th Jun 2011 13:20

Nice post FDG.

What I was alluding to in my initial post is that this, like many other aspects of our regulations, are completely open to individual interpretation. "Grey Area" just does not describe the regs well enough!

Out of interest, how did you determine or how do you know that the 57.1.3 reference is being read "too literally"?
What does "not available" mean? Not available because there never is one, or not available because something has happened and we cant get the normal TAF out for that place?


Interpretation.... That is the problem.
Some plain old common sense, proper planning and safe operation is the key.

'tis why you always have a bit of extra gas!

MOQ 18th Jun 2011 14:05

I would have to say "Yes, you do require Alternate" in this specific example.



AIP ENR 1.10 Para 1.2.1 / Jepps ATC AU-600 Para 1.2.1


A forecast must be either a flight forecast or an area forecast with an aerodrome forecast for the destination and, when required, the alternate aerodrome. For a flight to a destination for which a prescribed instrument approach procedure does not exist, the minimum requirement is an Area Forecast.

In this example, the aerodrome does have published instrument approach procedure (R-NAV), so we do require aerodrome forecast. But then...



AIP ENR 1.10 Para 1.2.3 / Jepps ATC AU-600 Para 1.2.3


For flights to a destination for which a aerodrome forecast is required and cannot be obtained or is "provisional", the flight is permitted to depart, provided an alternate aerodrome meeting all the requirements specified in Alternate Aerodromes paragraph is provided.

So, for the aerodromes WITH instrument approach procedure without TAF requires an Alternate.

In the same situation, but for the aerodromes WITHOUT instrument approach procedure...



AIP ENR 1.1 Para 58.2.12c / Jepps ATC AU-300 Para 3.2.12c


For aerodrome without an instrument approach procedure, the alternate minima are the lowest safe altitude for the final route segment plus 500 ft and a visibility of 8 km (also refer to Non-instrument Procedure Destination)

In this case, you do not require to have TAF (See first Quote), and you are not required to have an Alternate as long as you can satisfy the requirement above.


Clear as mud?

Kelly Slater 18th Jun 2011 14:30

Given that there are around 20 replies and FGD135 says that 90% are wrong then I have to say that he is right and no alternate is required, thus making me the other 5% of those that are correct.

Of course he is also correct simply because what he says is correct.

Xcel 18th Jun 2011 14:45

This question will clarify it for ya - ask any Rex or johnsons pilot what their requirements are for alternates when flyingto casino? and you'll get your answer...

No taf
instrument approach
arfor available

alternate Required or not?? Easy to carry alternate there - with so many close airports - but is it required? It's all in black and white!!

Xcel 18th Jun 2011 15:32

Just reread the thread and as usual das has confused everyone...

Thank god fdg is on here...

Did the original poster change his post - where did this random rnav and confusion come from?

to the original poster - simple answer for YOUR post - NO Alternate if lsalt +500 >8km for last route segment

MajorLemond 18th Jun 2011 16:47

To xcel..

Ok then... no alternate req`d....

Show me where in the regs?

cheers

MajorLemond 18th Jun 2011 17:02

just out of curiosity, where do people get the LSALT + 500" covering the requirement from???? we are dealing with 2 separate requirements here:

First and foremost: said Aerodrome HAS NO TAF (Jepps say TAF req`d or ALT req`d

Secondly it has no Navaid: In this instance Lsalt + 500" can be used to satisfy the NAVAID REQUIREMENT.

The lack of an Aerodrome forecast still stands..

Clearedtoreenter 18th Jun 2011 17:14


So, for the aerodromes WITH instrument approach procedure without TAF requires an Alternate.

Seems right. Take a pin with you if you get this in an IREX!

waren9 18th Jun 2011 20:01

Not trying to be a smartass either but could the 10%'ers please supply Jepp references as per the OP's original request?
:confused:

ThePaperBoy 18th Jun 2011 21:39

The reference is in post number 3 - people just have different interpretations of those paragraphs.

I'm with the guys that read it as: no TAF available due to no instrument approach at the field, use the ARFOR and the line about LSALT + 500 (not an automatic alternate required).

A number of those in the know (CASA FOIs, CPs, ATOs etc) also support the view about the "TAF not being available or PROV" refers to the TAF normally being available for use. From memory Bob Tait also went down this path with his IREX book (not that Bob sets the rules but it is a good indication of the answer the test will be looking for if this is your main concern).

Add a pinch of common sense to your fuel calculations and you'll never get caught short. However, on a CAVOK or FEW day I'm not carrying fuel for an alternate many miles away because my aerodrome has no TAF/IAL. In the real world this will badly affect your payload considerations. Can't always just fill the tanks like during your CPL training.


I called a mate who informed me that the RNAV rules changed a while ago and can now under certain circumstances be counted as a radio aid when assessing the requirement for an alternate.
Only TSO146.

blacknight 18th Jun 2011 23:06

We seem to have done the alt due aids pretty well.
Since the destination would be considered to have no aid if you only had a C129 GPS then the rule in AIP ENR 58.2.12 (c) would apply which states the minima as the 500ft/8k thing. It also referrs to ENR 1.10 ss 1.4.1
If we didn't apply this rule away from the coast we couldn't go anywhere without aerial refuelling and a good bladder.
I'm enjoying the discussion on this thread as it seems that there are many interpretations of the same rules all from people with a ticket to go to the same places!!
PS I am assuming we are talking about a PVT flight.

Xcel 19th Jun 2011 01:32

Major lemon - read the original post(as in page one) before jumping up and down!!

das Uber Soldat 19th Jun 2011 02:58

"Just reread the thread and as usual das has confused everyone..."

well done ********. I quoted the regs and asked anyone to show me where its written otherwise. If you find that confusing go back to working in the hair salon. :rolleyes:

Captain Nomad 19th Jun 2011 05:57

FGD and Das, sorry, but you have both confused the issue a bit. FGD you have confused it a bit with the whole melding of VFR/IFR (Jepp ATC pg 304 3.2.12 referring to weather says "For IFR flights the alternate minima are as follows" and in 3.3.1 navaids it specifically says "A flight which is planned to be conducted under IFR on the last route segment") and a lack of distinguishing between wx and navaid alternate requirements. Also, the bit about places with TAF's USUALLY available is a red herring.

Das, you have confused it by saying "It's irrelevant if you have the ability to do an instrument approach or not." It is actually very relevant. Furthermore, you also have not distinguished well between navaid and wx requirements. You did fix up the RNAV bit though regarding it being a substitute for a navaid UNDER CERTAIN CONDITIONS.

I will use examples to try and help illustrate. But it is important to be clear about whether we require the alternate based on wx or navaid (I have ignored lights for simplicity and because it is not relevant to the original 'day' question, I am also assuming PVT/AWK category of operation).

Two locations for example: Coondewanna (no TAF ever - RNAV approach available, no navaid) and Cessnock (assume no TAF available - no approach available, no navaid).

When considering weather, is an alternate required?

Coondewanna: YES (Jepp ATC pg 304 3.2.12 b. - "For aerodromes with an instrument approach procedure where an aerodrome forecast is unavailable... must make provision for a suitable alternate...") Notice it doesn't matter what type or definition of 'unavailable' exists here. It matters not whether it is a place like Leinster on the weekend (TAF during the day only and not on weekends - it also has instrument approaches available), or Coondewanna (no TAF ever - RNAV approach available) - the answer is still the same if the location has an IAP.

Cessnock: CONDITIONAL NO (Jepp ATC pg 304 3.2.12 c. - "For aerodromes without an instrument approach procedure, the alternate minima are the LSALT for the final route segment plus 500ft and vis 8km") By the way, how many of you have a last route segment that is contained fully within the forecast region of a TAF? ARFORs can be, and indeed have to be used when determining this - seriously... If no TAF available alternate required as per Jepp ATC pg 303 3.1.3

When considering navaids, is an alternate required?
Coondewanna & Cessnock: CONDITIONAL NO (Jepp ATC pg 304 3.3.2 - "...a flight may be planned under IFR by day to a destination aerodrome which is not served by a radio navigation aid without the requirement to provide for a suitable alternate aerodrome provided that:

a. not more than SCT cloud is forecast below the final route segment LSALT plus 500 ft and forecast visibility at the destination aerodrome is not less than 8km; and
b. the aircraft can be navigated to the destination aerodrome in accordance with flight under IFR navigation requirments.")

Okay, so my answer to the original question? The question matches the Coondewanna example therefore, YES - it does require an alternate due to weather alternate requirements only. However all you have to do is remove one aspect of the question and change it to the Cessnock example (no RNAV approach available) and the answer becomes a CONDITIONAL NO. The key thing is whether the location has an instrument approach procedure.

waren9 19th Jun 2011 06:05

Thankyou CN, that made sense to me.

das Uber Soldat 19th Jun 2011 07:44

Thanks nomad, that seems a logical interpretation.

MajorLemond 19th Jun 2011 09:44

Nomad,

Thanks for clarifying that, It`s exactly what I thought and the distinction you made between aerodromes with an IAL and one without makes it much easier to interpret the meaning.



Thanks again :ok:

GBO 19th Jun 2011 09:53

If there isn't a TAF, common sense would say, you would carry fuel for an alternate. You wouldn't want to get to the destination and find a howling crosswind that's beyond the aircraft's limits!

Checkboard 19th Jun 2011 14:23

If you commit the aircraft to flying into a cloud, you have to guarantee that you can safely get it out of the clouds.

That's either by:
  1. an instrument approach to an airport, with the weather forecast to be comfortably above the minimum descent alt, or
  2. by flying the aircraft on a leg with the cloud forecast to be comfortably above the lowest safe altitude, so that you can reasonably expect to become visual while still safe from terrain and continue for a visual approach.

Option 2 requires an Area forecast, as you are considering flight in an area to become visual, not around an airport.

blacknight 19th Jun 2011 21:09

CN,
I agree with your assesment except to further qualify that in the original post if you had a TSO 129 GPS this aerodrome would be considered to be a "no aid" destination so the answer would be a conditional no alt required if you can get visual before reaching LSALT. Assumes you can get a good area forecast. On the other hand if you think it will be IMC at the destination then ALT definitely required.


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