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182 crashed into trees at Porepunkah

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182 crashed into trees at Porepunkah

Old 21st Jan 2023, 23:33
  #201 (permalink)  
 
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And, so far as I can tell, it’s no different today. I’ve done it many times. But here is the key point re VFR:
as long as you were above 3000amsl/1000agl
Above that line in the sky, the operational requirement in the definition of VMC in MOS Part 91 does not apply. My educated guess is that’s because above that line you’re not going to collide with the ground or water.
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Old 22nd Jan 2023, 01:00
  #202 (permalink)  
 
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If you’re really flying NVFR in G at or below 3,000’ AMSL or 1,000’ AGL and [i]really “can’t see sh*t” - nothing, even in the direction you’re flying - I really wish you luck
Why do you need luck Clinton? You've pre plotted your flight on a WAC with necessary splay from departure point out to the required distance off track, and likewise at destination, noted the highest elevation of obstacles within that area and plan the flight at an elevation of at least 1,000' above that highest obstacle. If you comply with that requirement how are you
My educated guess is that’s because above that line you’re not going to collide with the ground or water.
You see dragons where none are to be seen.
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Old 22nd Jan 2023, 21:43
  #203 (permalink)  
 
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Originally Posted by Squawk7700
Sighted every 30 minutes otherwise you need to be endorsed for VOR or GPS (when you’re above cloud).

Is that still the case these days?
Yep. ENR 1.1-4.2 "When navigating by visual reference to the ground or water.."

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Old 22nd Jan 2023, 21:59
  #204 (permalink)  
 
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Originally Posted by Clinton McKenzie
And, so far as I can tell, it’s no different today. I’ve done it many times. But here is the key point re VFR:
as long as you were above 3000amsl/1000agl
Above that line in the sky, the operational requirement in the definition of VMC in MOS Part 91 does not apply. My educated guess is that’s because above that line you’re not going to collide with the ground or water.
Clinton, can you please explain why you keep harping on endlessly about this "line in the sky" that, AFAICT, relates to nothing more than remaining "clear of cloud" in VMC?!??

For starters, ENR 5.4-1 and AIP GEN 3.3 indicates your LSALT must be greater than 1,360' AGL (not 1,000') and there are plenty of places along the eastern seaboard where flying at 3,000' AMSL will send you into a hillside.

I suspect you're getting a little confused, because your last paragraph is at best misleading, if not entirely incorrect.

Last edited by PiperCameron; 22nd Jan 2023 at 22:15.
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Old 23rd Jan 2023, 00:36
  #205 (permalink)  
 
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If, as far as you can tell, the line in the sky relates to “nothing more than remaining clear of cloud”, you’re not reading and comprehending what Table 2.07 in MOS Part 91 says. Could you please (please) go and read that Table, and in particular Item 4 in that Table? All the way from the left column to the right column. Then read what’s above that Table.

If, for example, you are flying at 1,000’ AGL in G above 8/8ths of fog and below a layer of 8/8ths of cumulous with bottoms of - pick any number - 2,500’, you are “clear of cloud”. But are you operating in VMC as defined in MOS Part 91? I think not. You’re at or below 1,000’ AGL. If I’m wrong, it means the operational requirement in the final column against Item 4 in that Table is meaningless.

And I draw a distinction between “operating” generally and navigating and position fixing. I consider navigating and position fixing to be a subset of operating. There’s that saying about “aviate, navigate, communicate”.


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Old 23rd Jan 2023, 00:39
  #206 (permalink)  
 
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your LSALT must be greater than 1,360' AGL (not 1,000')
Not strictly correct, if the highest obstacle is more than 360' above the terrain (say TV antenna) LSALT is 1,000' above that object (antenna), if the antenna is less than 360' or there being no antenna the LSALT is then 1,360 above the terrain, if the elevation of the highest terrain or obstacle is not above 500' the LSALT must be not less than 1,500'.

One area not mentioned is weather forcast, if planning a NVMC what cloud base will you accept above your LSALT, Clinton's 3,000AMSL 1,000AGL says clear of cloud, you really, really going to accept that?
If, for example, you are flying at 1,000’ AGL in G above 8/8ths of fog
Well you're not in sight of ground or water so it's a no no.
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Old 23rd Jan 2023, 00:55
  #207 (permalink)  
 
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That’s precisely my point!

And, it’s a no no if you’re flying along at 3,500’ AMSL [sorry: I meant 3,000' AMSL] above 8/8ths of fog and can’t see any ground or water.

Last edited by Clinton McKenzie; 23rd Jan 2023 at 03:20. Reason: Mistake in the AMSL number.
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Old 23rd Jan 2023, 01:18
  #208 (permalink)  
 
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Originally Posted by megan
One area not mentioned is weather forcast, if planning a NVMC what cloud base will you accept above your LSALT, Clinton's 3,000AMSL 1,000AGL says clear of cloud, you really, really going to accept that?
Simple. Since for a NVFR flight you must maintain VMC, then the cloud base (for the entire route) must be greater than LSALT + 1,000'. If not, you can't and you don't depart.


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Old 23rd Jan 2023, 01:26
  #209 (permalink)  
 
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Originally Posted by Clinton McKenzie
And, it’s a no no if you’re flying along at 3,500’ AMSL above 8/8ths of fog and can’t see any ground or water.
By day, yes.. but by night, it's not relevant. Night VFR does not depend solely upon position fixing by ground or water - refer posts above.

Under NVFR you must assume the 8/8ths fog (and various other monsters) are waiting for you below your LSALT and be competent to navigate by other means. That's why NFVR is a Rating, not simply an endorsement.
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Old 23rd Jan 2023, 01:54
  #210 (permalink)  
 
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Nor does day VFR depend solely upon position fixing by ground or water.

But I can see that you’ve come to the conclusion that the operational requirement in Item 4 of Table 2.07 of MOS Part 91 has no application to NVFR operations in G at or below the higher of 3,000’ AMSL and 1,000’ AGL. Presumably, then, the rules (as you interpret them) do not prohibit a NVFR departure from an unlit aerodrome into inky blackness in which the pilot can’t see sh*t, provided the forecast cloud base is OK. (Just to circle back to the original theoretical question…).
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Old 23rd Jan 2023, 02:07
  #211 (permalink)  
 
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Hot off the press from the CASA 'Regulatory Guidance Centre':
Question: Does an aircraft being operate NVFR in G airspace at or below whichever is the higher of 3,000’ AMSL and 1,000’ AGL have to remain in VMC as defined in Part 91 MOS and comply with the corresponding operational requirement that: “Aircraft must be operated in sight of ground or water”?

If yes, does that mean that the pilot in command of an NVFR flight must, whenever operating at or below whichever is the higher of 3,000’ AMSA and 1,000’ AGL in G airspace, be able to physically see the ground or water?

Answer: An aircraft operating as a VFR flight (day or night) must comply with the VMC criteria referred to in regulation 91.280 of the Civil Aviation Safety Regulations 1998 (CASR) for the aircraft and airspace in which the flight is conducted. Division 2.4 of the Part 91 Manual of Standards (MOS) prescribes requirements relating to the operation of an aircraft for a VFR flight.

When operating below 1000ft AGL or 3000ft AMSL (whichever is higher), the aircraft must be operated in sight of ground or water, and the pilot must be able to physically see ground or water. This is illustrated in Table 2.07 (3) of the Part 91 MOS.

If something is in sight or within sight, you can see it. If it is out of sight, you can't see it. To apply this rule you must be able to actually see the ground or water.

The only time a NVFR flight would be operating lower than 3000ft AMSL or 1000ft AGL would be in accordance with subregulation 91.277(3) of CASR - taking off or landing or within the NVFR circling area of an aerodrome (within 3NM). At any other time, the aircraft must be at or above the NVFR LSALT in accordance with subregulation 91.277(2) - 1000 feet above the highest obstacle within 10NM of the aircraft. This height will always be above 1000ft AGL.

Further information is available in the Visual Flight Rules Guide on page 205 and may be applicable to your enquiry.

This guidance is current at the time it has been provided, however may be subject to change over time or at the discretion of the policy holder.
I wouldn't have used the word "illustrated", but their point is clear. And "this height" may always be above 1,000 AGL, but it won't necessarily always be above 3,000' AMSL.

Do with that what you will.
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Old 23rd Jan 2023, 04:38
  #212 (permalink)  
 
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Originally Posted by Clinton McKenzie
But I can see that you’ve come to the conclusion that the operational requirement in Item 4 of Table 2.07 of MOS Part 91 has no application to NVFR operations in G at or below the higher of 3,000’ AMSL and 1,000’ AGL. Presumably, then, the rules (as you interpret them) do not prohibit a NVFR departure from an unlit aerodrome into inky blackness in which the pilot can’t see sh*t, provided the forecast cloud base is OK. (Just to circle back to the original theoretical question…).
Well, yes. As per the answer you got from CASA:
The only time a NVFR flight would be operating lower than 3000ft AMSL or 1000ft AGL would be in accordance with subregulation 91.277(3) of CASR - taking off or landing or within the NVFR circling area of an aerodrome (within 3NM).
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Old 23rd Jan 2023, 11:13
  #213 (permalink)  
 
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.. and you can't circle within 3nm of the runway during the climb to 3000/LSALT without being able to fix your position relative to the runway - so you need to see the runway, and thus need lights for take-off (or sufficient ambient moon or ground lighting).
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Old 23rd Jan 2023, 13:54
  #214 (permalink)  
 
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the pilot must be able to physically see ground or water..........If something is in sight or within sight, you can see it. If it is out of sight, you can't see it. To apply this rule you must be able to actually see the ground or water.
That piece of CASA's advice is bollox, light is an electromagnetic radiation of a frequency that the human retina is able to detect and form an image in the brain. From whence is the ground or water accessing this electromagnetic radiation in order for you to see same? The requirement is to be in sight, not to be able to see. With a half moon the entire moon is in your sight but you can only see half of it, because it's the only bit radiating electromagnetic radiation in the visible spectrum. To be able to see the ground or water the guy is saying you should be able to discern every tree, unlit house, chicken coop, horse and cow, or estimate the wind strength and direction over water by observation of the waves, and what is going to provide the source of illumination, only fly when no cloud and a full moon? Get real. Now if we were able to see in the infra red spectrum different story.


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Old 23rd Jan 2023, 21:24
  #215 (permalink)  
 
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Originally Posted by Checkboard
.. and you can't circle within 3nm of the runway during the climb to 3000/LSALT without being able to fix your position relative to the runway - so you need to see the runway, and thus need lights for take-off (or sufficient ambient moon or ground lighting).
Sensibly, yes.. but legally, no. If the aerodrome is serviced by navaids or you have a certified RNP2 or better GNSS device on board you're competent to use, given the stated requirement is to "remain within 3nm", then it seems legally you could indeed depart.

If you're flying the aircraft properly NVFR, then the first opportunity you have to look back for the runway won't be until after you turn crosswind anyway, so whether or not it's lit (or the lights have timed out on you) is somewhat irrelevant... but if you get anywhere near 3 miles spiralling up then you better look out - Clinton will be watching!!
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Old 23rd Jan 2023, 23:12
  #216 (permalink)  
 
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The only time a NVFR flight would be operating lower than 3000ft AMSL or 1000ft AGL would be in accordance with subregulation 91.277(3) of CASR - taking off or landing or within the NVFR circling area of an aerodrome (within 3NM).
Is that true?

Are there no circumstances in which it is 'legal' to cruise at 2,500' AMSL NVFR? If, for example, LSALT for A to B is 1,500' AMSL and forecast and actual cloud base is 5,000', what rule says you can't cruise A to B at 2,500' AMSL NVFR (provided, of course, that you operate in sight of the ground or water)?
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Old 24th Jan 2023, 00:06
  #217 (permalink)  
 
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Originally Posted by Clinton McKenzie
Is that true?

Are there no circumstances in which it is 'legal' to cruise at 2,500' AMSL NVFR? If, for example, LSALT for A to B is 1,500' AMSL and forecast and actual cloud base is 5,000', what rule says you can't cruise A to B at 2,500' AMSL NVFR (provided, of course, that you operate in sight of the ground or water)?
Congratulations, Clinton. Now you've got CASA confused!
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Old 24th Jan 2023, 00:50
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Originally Posted by Fort Fumble
When operating below 1000ft AGL or 3000ft AMSL (whichever is higher), the aircraft must be operated in sight of ground or water, and the pilot must be able to physically see ground or water. This is illustrated in Table 2.07 (3) of the Part 91 MOS.
So...UUhhhh....How does that work for a NVFR departure with no external lighting beyond the runway? Soon as you cross the upwind threshold you're reliant on instruments. Or is it "Thou shall fly NVFR only within the 3 days either side of a full moon"??
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Old 24th Jan 2023, 01:08
  #219 (permalink)  
 
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Given the complex, convoluted dog's breakfast they've created, and continue to create, who wouldn't be confused, PiperCameron? The people answering the questions may be confident as to the validity of their conclusions and the relevance and accuracy of the facts they assert, but to pick up megan's theme: there be dragons in there!
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Old 24th Jan 2023, 01:48
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Originally Posted by megan
That piece of CASA's advice is bollox, light is an electromagnetic radiation of a frequency that the human retina is able to detect and form an image in the brain. From whence is the ground or water accessing this electromagnetic radiation in order for you to see same? The requirement is to be in sight, not to be able to see. With a half moon the entire moon is in your sight but you can only see half of it, because it's the only bit radiating electromagnetic radiation in the visible spectrum. To be able to see the ground or water the guy is saying you should be able to discern every tree, unlit house, chicken coop, horse and cow, or estimate the wind strength and direction over water by observation of the waves, and what is going to provide the source of illumination, only fly when no cloud and a full moon? Get real. Now if we were able to see in the infra red spectrum different story.


CASA's 'Regulatory Guidance Delivery' folk omitted what I consider to be fundamentally important, intersecting definitions:
visibility means the ability, as determined by atmospheric conditions and expressed in units of distance, to see and identify prominent unlighted objects by day and prominent lighted objects by night.

VMC (short for visual meteorological conditions) means meteorological conditions that meet the VMC criteria.

VMC criteria:

(a) for a class of aircraft (other than Part 131 aircraft) and a class of airspace (including flight visibility and distance from cloud)—means the criteria prescribed for the class of aircraft and class of airspace by the Part 91 Manual of Standards; and

(b) for Part 131 aircraft and a class of airspace (including flight visibility and distance from cloud)—means the criteria prescribed for the aircraft and class of airspace by the Part 131 Manual of Standards
(And "flight visibility" is defined to have the same meaning as in Annex 2 to the Chicago Convention. "The visibility forward from the cockpit of an aircraft in flight".)
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