IFR Approach to minimums..are you allowed?
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IFR Approach to minimums..are you allowed?
Of interest to all you "bus drivers" flying around (and through) the land of the long white cloud.
Are you aware of the CAA Rule Parts 121.159, 125.159, and 135.159 that read as follows...
121.159 Aerodrome operating minima – IFR flight
(a) A pilot-in-command shall not continue an instrument approach to an aerodrome past the final approach fix or, where a final approach fix is not used, the final approach segment of the instrument approach procedure if, prior to passing the final approach fix or the final approach segment, current meteorological information indicates the visibility at the aerodrome is less than the visibility prescribed under Part 95 for the instrument approach procedure being used.
(b) For the purpose of this rule, the final approach segment begins—
(1) at the final approach fix or facility prescribed in the instrument approach procedure; or
(2) when a final approach fix is not prescribed for a procedure that includes a procedure turn, at the point where the procedure turn is completed and the aeroplane is established on the final approach course within the distance prescribed in the procedure.
[Until Part 95 comes into force, instrument approach procedures are prescribed under Part 19]
Are you aware of the CAA Rule Parts 121.159, 125.159, and 135.159 that read as follows...
121.159 Aerodrome operating minima – IFR flight
(a) A pilot-in-command shall not continue an instrument approach to an aerodrome past the final approach fix or, where a final approach fix is not used, the final approach segment of the instrument approach procedure if, prior to passing the final approach fix or the final approach segment, current meteorological information indicates the visibility at the aerodrome is less than the visibility prescribed under Part 95 for the instrument approach procedure being used.
(b) For the purpose of this rule, the final approach segment begins—
(1) at the final approach fix or facility prescribed in the instrument approach procedure; or
(2) when a final approach fix is not prescribed for a procedure that includes a procedure turn, at the point where the procedure turn is completed and the aeroplane is established on the final approach course within the distance prescribed in the procedure.
[Until Part 95 comes into force, instrument approach procedures are prescribed under Part 19]
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I have it on good authority that CAA are taking an "active interest" in the topic and was just wanting to "raise awareness" for those that might want to "take a look" on those occasions where the advertised conditions might not quite be what is required.
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Yip!
I guess the real issue here comes that when the weather is as the rule says "at minimums" one has to make a decision as to whether the conditions are fluctuating? More often than not (unless its fog in HN Slackie then its there a looooong time!
LOL) when the weather is this poor it does often fluctuate and so where does one draw the line at having a go!?
It would be like departing on a tempo where the tempo is saying conditions will be below minimum, you are still legal to depart because tempo is a fluctuating remark to a point? you would have a go at the apporach in a 'Gap'.
Hey Slackie, whats the onus on you as a controller to advise an aircraft on approach of weather conditions? I presume you would advise an aircraft if it goes below minima so that aircraft can initaite the missed app?
Good to see you ATC's giving us a heads up!
I guess the real issue here comes that when the weather is as the rule says "at minimums" one has to make a decision as to whether the conditions are fluctuating? More often than not (unless its fog in HN Slackie then its there a looooong time!
LOL) when the weather is this poor it does often fluctuate and so where does one draw the line at having a go!?It would be like departing on a tempo where the tempo is saying conditions will be below minimum, you are still legal to depart because tempo is a fluctuating remark to a point? you would have a go at the apporach in a 'Gap'.
Hey Slackie, whats the onus on you as a controller to advise an aircraft on approach of weather conditions? I presume you would advise an aircraft if it goes below minima so that aircraft can initaite the missed app?
Good to see you ATC's giving us a heads up!
Grandpa Aerotart
This is just the Kiwi version of UK CAA 'approach bans'. Unless RVR is at or above the appropriate minimum you are banned from preceding below 1000', essentially, on the approach. If you do so they have several 'standard phrases' that indicate you're pissing em off but they won't actually order you to go around...but a world of hurt awaits you when you pull up at the aerobridge.
Difference being, I suspect, that UK ATC have transmissometers that show them what the actual RVR is out on the runway as opposed to having an educated guess and then trying to micromanage your approach and landing. Clearly AKL has transmissometers these days but what of other NZ airports?
Difference being, I suspect, that UK ATC have transmissometers that show them what the actual RVR is out on the runway as opposed to having an educated guess and then trying to micromanage your approach and landing. Clearly AKL has transmissometers these days but what of other NZ airports?
Cathay has had the same "approach ban" rule below 1000' AGL for years and years.
As far as I was aware it was a company thing, maybe it came from the UK CAA and CX followed it?
However it's up to the Crew to use and abuse, not ATC.
And you don't need RVR readings either, VIS will be controlling if RVR is not available.
As far as I was aware it was a company thing, maybe it came from the UK CAA and CX followed it?
However it's up to the Crew to use and abuse, not ATC.
And you don't need RVR readings either, VIS will be controlling if RVR is not available.
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Slackie,
As far as I know it's a reasonably well known rule, particuarly at Eagle where it often comes up in the interview when discussing hypothetical approaches, "...what would you do if ATC advised that vis was below prior to the FAF?" and then " ... but what if you were inside the FAF and ATC advised the same. What would you do?" The rule only applies to visibility, so if you've started an approach and it goes below mins then you could theoretically continue and "have a look".
CAA taking an "active interest"?? Are you refering to a recent incident that was reported by HN Twr involving a regular Air Transport Operator?
S2K
As far as I know it's a reasonably well known rule, particuarly at Eagle where it often comes up in the interview when discussing hypothetical approaches, "...what would you do if ATC advised that vis was below prior to the FAF?" and then " ... but what if you were inside the FAF and ATC advised the same. What would you do?" The rule only applies to visibility, so if you've started an approach and it goes below mins then you could theoretically continue and "have a look".
CAA taking an "active interest"?? Are you refering to a recent incident that was reported by HN Twr involving a regular Air Transport Operator?
S2K
The Oz regs seem to be a little more flexible. Perhaps fog at a primary airport would be a no-no but in other cases:
and that is why CASA says:
Part of 257 says:
It is very difficult, IMHO, for anybody except the flight crew to know what can be seen at the designated minimum.
176A Determination of visibility and cloud base for I.F.R. flights
(1) Subject to regulation 257, the pilot in command of an aircraft
operating under the Instrument Flight Rules is responsible for
determining the visibility and cloud base for the take-off and landing
of the aircraft.
(2) In determining visibility, the pilot in command of an aircraft must take
into account the meteorological conditions, sunglare and any other
condition that may limit his or her effective vision through the
windscreen of the cockpit of the aircraft.
(3) In determining the cloud base, the pilot in command of an aircraft
must:
(a) for take-off—take into account the current available weather
forecasts and reports; and
(b) for landing—determine the cloud base from the cockpit of the
aircraft while in flight.
(1) Subject to regulation 257, the pilot in command of an aircraft
operating under the Instrument Flight Rules is responsible for
determining the visibility and cloud base for the take-off and landing
of the aircraft.
(2) In determining visibility, the pilot in command of an aircraft must take
into account the meteorological conditions, sunglare and any other
condition that may limit his or her effective vision through the
windscreen of the cockpit of the aircraft.
(3) In determining the cloud base, the pilot in command of an aircraft
must:
(a) for take-off—take into account the current available weather
forecasts and reports; and
(b) for landing—determine the cloud base from the cockpit of the
aircraft while in flight.
(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.
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Why was this moved???
MODERATORS....Why was this moved??? It directly involves RPT and scheduled Airline pilots NOT GA pilots...CAA Rule Parts 121 and 125 apply to Medium and Large aircraft on Air Transport Operations!!! Please consider moving this back to the other forum!!!!
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S2K...nothing was "reported by HN Twr" as you put it...it was as much a surprise for us as anyone else...in fact none of us were aware of the rules as they don't appear in any of our documentation...I had to go looking to find the references.
In HN's case we report the vis as we see it wrt known landmarks and their distances from the tower...we recognise that what we see may be (and in many cases IS) completely different to the vis on the actual runway and as viewed from the cockpit.
We know what the minimums are for the approaches, but do not know what minimums may be imposed by individual companies or in fact what minimums a pilot may impose on him/herself that may be well above the published ones. In fact if memory serves correctly, some companies even have different missed approaches than those published (e.g. I think one company has the MA from NZNR involving a 5 or 10 degree turn that isn't in the published procedure).
In HN's case we report the vis as we see it wrt known landmarks and their distances from the tower...we recognise that what we see may be (and in many cases IS) completely different to the vis on the actual runway and as viewed from the cockpit.
We know what the minimums are for the approaches, but do not know what minimums may be imposed by individual companies or in fact what minimums a pilot may impose on him/herself that may be well above the published ones. In fact if memory serves correctly, some companies even have different missed approaches than those published (e.g. I think one company has the MA from NZNR involving a 5 or 10 degree turn that isn't in the published procedure).
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At my work, we definitely make this aware to the kiwi students and the UK students (app ban). But I always ask; why have app minima if you’re going to supersede what’s on the plate with this limitation?
I definitely see the logic with a precision approach & this rule, as i could imagine something with a crap load of inertia (74/77) doing at missed at 200AGL would still coming bloody close to the ground.
As for HN, need more rwys? today was "crazy times"
I definitely see the logic with a precision approach & this rule, as i could imagine something with a crap load of inertia (74/77) doing at missed at 200AGL would still coming bloody close to the ground.
As for HN, need more rwys? today was "crazy times"
Bloggs,
You've hit on a particular bug-bear of mine.
Virtually no where else is it legal to shoot an approach past an approach ban point with conditions reported below minima, as Chimbu has said.
As an FO in Aus, though, I more than once had Captains who would "Take a look" when conditions were obviously below minima. In my opinion this was illegal as there was no "reasonable grounds" to think they would be able to land, but it was never questioned and was a cultural norm throughout Aussie airlines.
I believe Qantas has instigated the equivelent of an approach ban in recent years, and good on them for it.
True, but if the vis is below minima before they ebven start, they shouldn't be there!!
If we could now just convince them to always carry an alternate.....
You've hit on a particular bug-bear of mine.
Virtually no where else is it legal to shoot an approach past an approach ban point with conditions reported below minima, as Chimbu has said.
As an FO in Aus, though, I more than once had Captains who would "Take a look" when conditions were obviously below minima. In my opinion this was illegal as there was no "reasonable grounds" to think they would be able to land, but it was never questioned and was a cultural norm throughout Aussie airlines.
I believe Qantas has instigated the equivelent of an approach ban in recent years, and good on them for it.
It is very difficult, IMHO, for anybody except the flight crew to know what can be seen at the designated minimum.
If we could now just convince them to always carry an alternate.....
who makes such decisions & when?
It isn't a decision, it's a report. At a controlled airport ATC have visibility reports available from a number of sources, the most sophisticated being a transmissiometer, the least being a groundsman counting runway lights. In any case, what is obtained is a Reported Ceiling and Visibility.
In most countries if this number is less than that required by you (and THAT is a number which might have several variables) you cannot do an approach to minima. In Australia the "Reasonable expectation" loophole is used as an open invitation to have a go.
I believe this will have to be cleaned up before Australia gets Cat II or Cat III approaches, as go-around from those minima are high-risk events which should happen as the rare exception, not the routine event after "Having a look".
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Doesn't Cat IIIC have a 0 feet minima, in which case you wouldn't be having a look, you would be landing...
The groundsman is probaly more accurate than the transmissiometer, as the beam of light is very narrow and only measures in one direction, also the height at which it measures is considerably lower than the eye height of most heavy jets...
the most sophisticated being a transmissiometer, the least being a groundsman counting runway lights.
HH,
Cat IIIB CAN have no decision height (which is actually subtley different from a 0' decision height) but you require 50m Vis to shoot the approach, mostly so you can taxi when you get there!!!
IIIC is, in theory, 0/0, but doesn't actually exisit in practice at the moment.
Actually Cat II and IIIA are where things get tricky, as a go-around from minima (100 and 50' respectivley) may result in a touch-down during the manoeuvre- one reason why the regs should ensure it doesn't happen very often!!
Cat IIIB CAN have no decision height (which is actually subtley different from a 0' decision height) but you require 50m Vis to shoot the approach, mostly so you can taxi when you get there!!!
IIIC is, in theory, 0/0, but doesn't actually exisit in practice at the moment.
Actually Cat II and IIIA are where things get tricky, as a go-around from minima (100 and 50' respectivley) may result in a touch-down during the manoeuvre- one reason why the regs should ensure it doesn't happen very often!!
Wiz,
First, you may remember Operational Control. Then, ATC had the power to prevent you from commencing an approach if they deemed the weather to be below the minimums. The only power they have now is to close the aerodrome if hazardous conditions exist, and the CAR applies. In conditions and with the facilities )or lack thereof) that we have in Oz, I don't have a problem with the current rules where the PIC decides. As I mentioned in my earlier post, I don't think it'd be very clever to land if ATC was reporting the vis as 200m in fog.
The other issue is that at almost every aerodrome that is not at a capital city, "approach ban" system would be an abject failure because accurate met obs are just never available. The only practical option is to "have a look", which is allowed by the reg. We are all professionals and provided we have options eg an alternate or holding, then why would a crew deliberately press on below the minimums?
First, you may remember Operational Control. Then, ATC had the power to prevent you from commencing an approach if they deemed the weather to be below the minimums. The only power they have now is to close the aerodrome if hazardous conditions exist, and the CAR applies. In conditions and with the facilities )or lack thereof) that we have in Oz, I don't have a problem with the current rules where the PIC decides. As I mentioned in my earlier post, I don't think it'd be very clever to land if ATC was reporting the vis as 200m in fog.
The other issue is that at almost every aerodrome that is not at a capital city, "approach ban" system would be an abject failure because accurate met obs are just never available. The only practical option is to "have a look", which is allowed by the reg. We are all professionals and provided we have options eg an alternate or holding, then why would a crew deliberately press on below the minimums?
