IMC minimium
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IMC minimium
"The limits for an aproach for an IMC holder are what ever it states on the approach plate +px error corection (if any)."
I noticed this comment in a previous post. The minimium for IMC holders use to be more cautious than for IR holders. What has changed and is it a good thing.
I noticed this comment in a previous post. The minimium for IMC holders use to be more cautious than for IR holders. What has changed and is it a good thing.
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The way I was told during my CPL (allows privileges of an IMC - I never had a UK PPL let alone IMC) the legal minima were the same as for an IRed pilot - i.e. what you quote. The recommended minima were somewhat higher, and it might be considered foolish to ignore CAA SRG recommendations.
However, I have been corrected here on this before, so would like a definitive answer with reference if anyone has it. I have given up trying to find information in CAA online documentation. This will allow me to speak with authority if asked once I am a flying instructor.
However, I have been corrected here on this before, so would like a definitive answer with reference if anyone has it. I have given up trying to find information in CAA online documentation. This will allow me to speak with authority if asked once I am a flying instructor.
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In the IMC confuser and what I plan to use in the forthcoming exam are:
Precision Approach - Plate MDH + 200 + 50 PEC or 500ft aal whichever is greater
Non Precision - Plate MDH + 200 or 600ft aal whichever is greater
Have these changed then ?
Precision Approach - Plate MDH + 200 + 50 PEC or 500ft aal whichever is greater
Non Precision - Plate MDH + 200 or 600ft aal whichever is greater
Have these changed then ?
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SimJock
Those are the same numbers I learned for my IMC, long ago.
BUT ... the "recent" wisdom is that they are only "recommended" increases to the minima on the plates. The inference is that you can, in theory, legally continue down to the IR minima.
I suspect that may "technically" be right, but I'm not sure I'd advise it. You need to be very current to handle an approach to IR minima in real IMC.
Having done some ILS and NDB approaches today (under the hood) to keep my FAA IR current, I can tell you it ain't easy even if you are pretty current.
Those are the same numbers I learned for my IMC, long ago.
BUT ... the "recent" wisdom is that they are only "recommended" increases to the minima on the plates. The inference is that you can, in theory, legally continue down to the IR minima.
I suspect that may "technically" be right, but I'm not sure I'd advise it. You need to be very current to handle an approach to IR minima in real IMC.
Having done some ILS and NDB approaches today (under the hood) to keep my FAA IR current, I can tell you it ain't easy even if you are pretty current.
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I understood that it is the minima, for an IR rated pilot PLUS 200ft, with an absolute minimum of 500ft for a precison approach & 600ft for a non-precision approach. This is for an IMC rated pilot in current practice, which is defined as having done an instrument approach in the last 28 days.
As a semi-competant IMC rated pilot, (who does take regular practice of IF with an instructor, when rusty), I would not go below the above limits on my own.
BUT, as Send Clowns, asks, if this just the recommended limits or the LEGAL limits for IMC rated pilots? In all the CAA paperwork that I have seen, it is not really clear.
PS. Just had a look in LASORS 2002, but that just seems to say that for an IMC test or revalidation, the candidate must make a let down & approach to "Decision Height", but does not define DH, so do we assume that the IMC test is down to the SAME minima as the IR test? Now I really am confused
Mind you, the examiner who did my last IMC revalidation (in a twin) made me do a procedure ILS, assymetric & down to IR minima, but I assumed that is just 'cos he is sadist, who likes making me work hard
As a semi-competant IMC rated pilot, (who does take regular practice of IF with an instructor, when rusty), I would not go below the above limits on my own.
BUT, as Send Clowns, asks, if this just the recommended limits or the LEGAL limits for IMC rated pilots? In all the CAA paperwork that I have seen, it is not really clear.
PS. Just had a look in LASORS 2002, but that just seems to say that for an IMC test or revalidation, the candidate must make a let down & approach to "Decision Height", but does not define DH, so do we assume that the IMC test is down to the SAME minima as the IR test? Now I really am confused
Mind you, the examiner who did my last IMC revalidation (in a twin) made me do a procedure ILS, assymetric & down to IR minima, but I assumed that is just 'cos he is sadist, who likes making me work hard
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AIP Aerodromes Section 1.1.2 Aerdrome Operating Minima Item 3.3.3 contains the relevant text.
http://www.ais.org.uk/uk_aip/pdf/ad/30101.pdf
although it 'recomends' adding 200ft to the IR DH the absolute minima is still 500/600ft. Earlier on in the document, calculated minima are said to be mandatory.
http://www.ais.org.uk/uk_aip/pdf/ad/30101.pdf
although it 'recomends' adding 200ft to the IR DH the absolute minima is still 500/600ft. Earlier on in the document, calculated minima are said to be mandatory.
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Had a "one to one" discussion on this very thing with an inspector from the CAA a couple of months ago.
A local ATC were getting p****d off by IMC students suddenly doing the go araound at almost two miles out - screwed up their plans for the aircraft behind.....and the guy ahead in the training system who is usually turning back to have another go.
CAA man said, quite categorically, that the 500/600 is RECOMMENDED not mandatory - and continued approach to plate minima is perfectly acceptable.
Personally, I disagree - and always went with the 500/600 idea.
BTW - Simjock....when you do your forthcoming exam, try not to use the phrase
A precision approach does not have an MDH.
A local ATC were getting p****d off by IMC students suddenly doing the go araound at almost two miles out - screwed up their plans for the aircraft behind.....and the guy ahead in the training system who is usually turning back to have another go.
CAA man said, quite categorically, that the 500/600 is RECOMMENDED not mandatory - and continued approach to plate minima is perfectly acceptable.
Personally, I disagree - and always went with the 500/600 idea.
BTW - Simjock....when you do your forthcoming exam, try not to use the phrase
Precision Approach - Plate MDH + 200 + 50 PEC or 500ft aal whichever is greater
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GoneWest Your post has just raised another question in my mind. 
The initial IMC training that I did, plus refresher training since, for instrument approaches, has all been down to IR minima.
I assumed that this was for 2 reasons.
Firstly, it avoids annoying the ATC, as you mentioned, by go-arounds from 2 miles out.
Secondly, it makes the training far more useful, from my point of view. If I can fly an ILS down to 250ft fairly competantly, with an instructor, then I feel reasonably confident to do it down to 500ft on my own.
SO, what minima, do most IMC instructors teach to?
The initial IMC training that I did, plus refresher training since, for instrument approaches, has all been down to IR minima.
I assumed that this was for 2 reasons.
Firstly, it avoids annoying the ATC, as you mentioned, by go-arounds from 2 miles out.
Secondly, it makes the training far more useful, from my point of view. If I can fly an ILS down to 250ft fairly competantly, with an instructor, then I feel reasonably confident to do it down to 500ft on my own.
SO, what minima, do most IMC instructors teach to?
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It looks like the document has been moved. I found it at http://www.ais.org.uk/uk_aip/aip/pdf/ad/30101.pdf section 3.3.2
It states:-
Now, the question is, what is recommended? I think it can be argued that everything after the 'recommended' is just that - i.e., it is only recommended that the absolute minima is 500/600 ft. If it is mandatory, then why wasn't it written:-
However, perhaps the point is that to get this low you must be current at getting this low. Certainly when I did my IMC and subsequent renewals, my decision height was based on this recommendation.
It states:-
Pilots with a valid IMC/Instrument Weather Rating are recommended to add 200 ft to the Instrument Rated pilots' DH/MDH, but with absolute minima of 500 ft for a precision approach and 600 ft for a non-precision approach.
Pilots with a valid IMC/Instrument Weather Rating have an absolute minima of 500 ft for a precision approach and 600 ft for a non-precision approach and are recommended to add 200 ft to the Instrument Rated pilots' DH/MDH?
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Romeo Romeo Thanks for finding the very wording that was the subject of much dispute, at our local flying school, between, instructors, PPLs & students, on a Saturday morning, when it was TOO foggy even for IMC practice
The dispute being:-
Does the "recommended" ONLY relate to the first sub-clause "to add 200ft....." ?
Or does the "recommended" ALSO relate to the second sub-clause "but with an absolute minima of 500ft......" ?
Or, does the second sub-clause stand on its merits, & therefore the "absolute minima of 500ft......" means just that, so it is the LEGAL minima for IMC rated pilots ?
Now what we really need is a nit-picking pedantic flying lawyer, or just clarification from the CAA-SRG would do, please
The dispute being:-
Does the "recommended" ONLY relate to the first sub-clause "to add 200ft....." ?
Or does the "recommended" ALSO relate to the second sub-clause "but with an absolute minima of 500ft......" ?
Or, does the second sub-clause stand on its merits, & therefore the "absolute minima of 500ft......" means just that, so it is the LEGAL minima for IMC rated pilots ?
Now what we really need is a nit-picking pedantic flying lawyer, or just clarification from the CAA-SRG would do, please
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Hi folks,
Well as an IR holder (and previous IMC holder) as well as an instructor i think the privilages & minima are quite clear.
You must remember that obstacles on the approach and in the surrounding area may case the plate minima + 200' to be HIGHER than your 500/600' minima...therefore it would be prudent (and hence recommended - not the wording) to ensure that you are above the IR minima.
The minima is...
The highest of:
1. 500' precision, 600' non-precision
or
2. OCH + PEC (precision) or OCH (non-precision)
or
3. circling minima if the intended approach will not land on the instrument approach's runway.
It is recommended that you add 200' to no.2 due to the nature of the difference between IMC & IR training. The reason the wording is the way it is, is that take RAF Brize Norton, precision approach gives something like 280' dh from the plate + pec. +200 to this - still means you only get 480' - therefore you can only fly to 500'.
The only time with an IMC rating you could legally fly to approach plate minima (+PEC) is when no2 above comes out at 500' or above on a precision app, and 600' or above on a non-precision.
In all cases extreme cold temp error corrections should be applied to the result.
I hope this clears it up.
FF
Well as an IR holder (and previous IMC holder) as well as an instructor i think the privilages & minima are quite clear.
You must remember that obstacles on the approach and in the surrounding area may case the plate minima + 200' to be HIGHER than your 500/600' minima...therefore it would be prudent (and hence recommended - not the wording) to ensure that you are above the IR minima.
The minima is...
The highest of:
1. 500' precision, 600' non-precision
or
2. OCH + PEC (precision) or OCH (non-precision)
or
3. circling minima if the intended approach will not land on the instrument approach's runway.
It is recommended that you add 200' to no.2 due to the nature of the difference between IMC & IR training. The reason the wording is the way it is, is that take RAF Brize Norton, precision approach gives something like 280' dh from the plate + pec. +200 to this - still means you only get 480' - therefore you can only fly to 500'.
The only time with an IMC rating you could legally fly to approach plate minima (+PEC) is when no2 above comes out at 500' or above on a precision app, and 600' or above on a non-precision.
In all cases extreme cold temp error corrections should be applied to the result.
I hope this clears it up.
FF
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Oh yes - forgot to mention - with an IMC rating your are also limited to an RVR of 1800m minimum - or the approach plate minima if higher.
Even an IR rated pilot on an SPA must use 800m or the approach plate - whichever is the higher.
And also its illegal to descend below 1000' aal if your minima is not met/exceeded according to ATC/ATIS information.
Hope this helps,
FF
Even an IR rated pilot on an SPA must use 800m or the approach plate - whichever is the higher.
And also its illegal to descend below 1000' aal if your minima is not met/exceeded according to ATC/ATIS information.
Hope this helps,
FF
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The more I look at it, the more I think that the whole sentence is a recommendation. They could have made it clearer by reiterating the 'recommended' word in the second part of the sentence, but probably thought it was overkill. Certainly, if the 500/600ft rule were mandatory, then it could have been written to indicate this as demonstrated in my previous post.
I think the 1800m RVR is definitely mandatory although I can't find the reference to it in the AIP.
I think the 1800m RVR is definitely mandatory although I can't find the reference to it in the AIP.
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The legal minima is the System Minima. For practical purposes in light aircraft even IR rated pilots do not use this because their altimeters are uncalibrated, they add PEC.
The AIP advises IMC rated pilots to add the prescribed heights to give the minima you are all quoting. The Law however does not prescribe these additions, so unless you come below the system minima you are not illegal. To find out what is legal just read the ANO.
Common sense dictates that pilots scale their minima to match their experience. Hopefully we don't need laws to enforce common sense.
The AIP advises IMC rated pilots to add the prescribed heights to give the minima you are all quoting. The Law however does not prescribe these additions, so unless you come below the system minima you are not illegal. To find out what is legal just read the ANO.
Common sense dictates that pilots scale their minima to match their experience. Hopefully we don't need laws to enforce common sense.
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Thanks for that S&L. From what I remember, the only document concerning flying which is enshrined in our laws is the Air Navigation Order. However as you also state
and if you get it wrong, it carries an immediate death penalty!
Common sense dictates that pilots scale their minima to match their experience. Hopefully we don't need laws to enforce common sense
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"And also its illegal to descend below 1000' aal if your minima is not met/exceeded according to ATC/ATIS information"
Is this right? If so its a JAR thing. The pilot could still commence the approach, down to minimums, but once minimums are met then miss approach had to be performed....at least this is what the FAA state...
Cheers
EA
Is this right? If so its a JAR thing. The pilot could still commence the approach, down to minimums, but once minimums are met then miss approach had to be performed....at least this is what the FAA state...
Cheers
EA
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FF, Just a small point but the "approach ban" preventing you from descending below 1000' aal only applies to the RVR and not to the cloudbase. It is still legal to make an approach if the reported cloudbase is below the DA or MDA (actually DH or MDH) but not if the RVR is below the required figure for the particular approach.
My reading of the 800 RVR limit for single-pilot operations is that it only applies to public transport flights. However, the CAA have said in the past couple of years that it applies to all flights. How this can change without a change to the ANO is beyond me. It is also odd in that most single-pilot approaches are made in cat A aircraft with a much lower threshold speed than most public transport approaches.
RR, I have a feeling that the 1800m RVR is a licence restriction for IMC holders rather than anything else. My ANO says that a PPL without any ratings must have a min visibility of 3km (outside controlled airspace).
My reading of the 800 RVR limit for single-pilot operations is that it only applies to public transport flights. However, the CAA have said in the past couple of years that it applies to all flights. How this can change without a change to the ANO is beyond me. It is also odd in that most single-pilot approaches are made in cat A aircraft with a much lower threshold speed than most public transport approaches.
RR, I have a feeling that the 1800m RVR is a licence restriction for IMC holders rather than anything else. My ANO says that a PPL without any ratings must have a min visibility of 3km (outside controlled airspace).
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Whilst a particular action may not be illegal, don't forget Articles 63 and 64. Endangering the safety of an aircraft and of any person or property.
Your actions must bear a test of reasonableness under the prevailing circumstances.
Your actions must bear a test of reasonableness under the prevailing circumstances.
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FormationFlyer & Strateandlevel Sorry fellas, but I am now even more confused
I agree totally with FF's posting, & I do not fly below the limits that he set out, 'cos I know the my capabilities & I have a strong sense of self preservation
So, for example for an ILS, where OCH + pec = 250ft,
then my recommended minimum is the HIGHER of 450ft or 500ft, = 500ft
But is my LEGAL minimum .... 250ft or 450ft or 500ft?
Also for FF - as you are an instructor, could you confirm whether the CAA requires you to test IMC candidates down to the legal minima for IR holders, or the recommended (or legal?) minima for IMC holders?
Thanks for your help guys
I agree totally with FF's posting, & I do not fly below the limits that he set out, 'cos I know the my capabilities & I have a strong sense of self preservation
So, for example for an ILS, where OCH + pec = 250ft,
then my recommended minimum is the HIGHER of 450ft or 500ft, = 500ft
But is my LEGAL minimum .... 250ft or 450ft or 500ft?
Also for FF - as you are an instructor, could you confirm whether the CAA requires you to test IMC candidates down to the legal minima for IR holders, or the recommended (or legal?) minima for IMC holders?
Thanks for your help guys