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troddenmasses
29th Mar 2007, 12:29
I have an IMC that has just lapsed, and also happen to have just joined a new club. I was discussing doing some refresher training with the CFI, and was discussing minimums. I always believed that the minimum landing weather conditions for an IMC holder were 1800m vis and system minima + 50ft PEC + 200ft DH/MDH (with an absolute minimum of 500ft DH and 600ft MDH). As I flew from Cardiff, I always used 500ft as my Decision height.

This new CFI tells me that the rules have now changed, and said rather dismissively that if I did that nowadays, it would be illegal. Whilst I don't relish the idea of flying in pea soup type weather, I would like to know the actual minimums. I have trawled through LASORS, and found a mention of 'Schedule 8 of the ANO'. When I look this up, it doesn't mention weather minima. Can anybody point me in the right direction please?

'Chuffer' Dandridge
29th Mar 2007, 12:41
From the ANO:

Instrument meteorological conditions rating (aeroplanes)

(1) Subject to paragraph (2), the rating shall within the United Kingdom:

(a) entitle the holder of a United Kingdom Private Pilotís Licence (Aeroplanes) or a United Kingdom Basic Commercial Pilotís Licence (Aeroplanes) to fly as pilot in command of an aeroplane without being subject to the restrictions contained respectively in paragraph (2)(c) or (f) of the privileges of the United Kingdom Private Pilotís Licence (Aeroplanes) or (3)(g) or (i) of the privileges of the United Kingdom Basic Commercial Pilotís Licence (Aeroplanes);

(b) entitle the holder of a JARĖFCL Private Pilot Licence (Aeroplane) to fly as pilot in command of an aeroplane in Class D or E airspace in circumstances which require compliance with the Instrument Flight Rules.

(2) The rating shall not entitle the holder of the licence to fly:

(a) on a special VFR flight in a control zone in a flight visibility of less than 3 km; or

(b) when the aeroplane is taking off or landing at any place if the flight visibility below cloud is less than 1800 metres.

troddenmasses
29th Mar 2007, 12:52
OK, so if i'm talking about flying home to Filton or Cardiff, which has class D airspace all around it, if the weather is poor, and i'm returning IFR, I can fly with a visibility under cloud of 1800m - same as I ever could. Now how about the decision height. Say I'm using the ILS - can I still go down to 500ft? As I say, the CFI says that I can't, but I would like to see it somewhere - it isn't an easy one to find.

englishal
29th Mar 2007, 12:53
Minimums are the same as for the IR with regards DH / MDA.....

troddenmasses
29th Mar 2007, 13:00
I was absolutely sure that when I did my IMC originally, that 200 or 300 feet needed to be added for an IMC holder, and that the minimum DH was 500ft, and that the minimum MDH was 600ft. I have now been told by the CFI that this has increased substantially - are you saying that this isn't true, and that I can now fly down to IR minima? I would be very shocked at that - it doesn't seem the type of thing that the CAA would do.

vetflyer
29th Mar 2007, 13:13
minima are the same for both IR & IMC... BUT very strongly recommendaed to use the revised minima you suggest.

mm_flynn
29th Mar 2007, 13:13
This has been debated a number of times. I have never seen any legal references other than that quoted in post 2. I believe that it is 'recommended' (maybe in LASORS) that minima similar to what you have described apply. In addition, I believe that is what you are tested on and strongly encouraged to use as your absolute minima. However, I believe Englishal is correct - and this is not a recent change.

FlyingForFun
29th Mar 2007, 13:15
The increases in DH/MDH which you learnt when you did your IMC rating were, and always have been, recommended, but not legal limits. Chuffer's quote confirms this. I think you will find the recommendation somewhere in the AIP (not the ANO), but it is not mandatory. The minimum viz, however, is mandatory.

As for any recent changes, I don't know of any, and I have no idea what your CFI is talking about.

FFF
--------------

troddenmasses
29th Mar 2007, 13:15
Thank you very much for that. Can anybody point me in the correct direction to find minima? Many thanks in advance.

Posted at the same time as the above - I'll go have a nice browse of the AIP then..... Should while away the hours :)

Fuji Abound
29th Mar 2007, 13:41
Not again! (no disrespect TMs).

The position with regards to IMCR minima is clearly set out in the ANO.

The only possible debate is what is meant by the use of the words either side of recommended - some take the view the higher minima are recommended others that they are mandatory.

There was a very lengthy debate on this forum about this within the last year (use the search function) with both sides of the arguement being put.

At the time I wrote to the CAA and I for one was absolutely satisfied from their response beyond any possible doubt that the CAA consider the recommended higher minima are just that - recommended.

If you are in any doubt the best you can do is write to them for yourself - they are really very helpful, and I suspect have answered this question more than a few times.

That means your CFI is wrong and you might want to suggest to him if he is teaching the IMCR he should also write to the CAA so he can teach the rating correctly! :)

S-Works
29th Mar 2007, 13:43
The minima in law to land is 1800m forward viz. the minima for approach is 1800m forward met viz and the DH/MDA of the approach.
The recommndations to add 200ft plus PEC with suggested minima of 500ft PA 600ft NPA are contained in a PINK AIC.
An IMC only not in VERY current practice would be VERY stupid to attempt an approach beyond the 500/600ft recommendations In fact I would suggest even those are too low if you are not CURRENT.

troddenmasses
29th Mar 2007, 13:59
Thank you very much for that information. Believe me - I hate flying in poor weather, but believe the IMC to be a critical piece of training for flying in the UK. I have no intention of disappearing into nasty weather, just because my license says that I can.

What I don't like is being told by an authority figure that I can't do something because it's against the law, and then not going on to prove it. If it is against the club rules, fair enough - but don't quote rules as being from the CAA if they aren't.

Fuji Abound - Sorry if this has been asked before, but as I don't spend THAT much time on here, I haven't seen that particular question asked before. It isn't quite as popular as the 'Can I log time spent flying next to my friend as P1s' or 'Can I wear gold braid'. I did try the search function, but didn't really come up with a satisfactory answer. I suppose that when using any search function, you really have to know the key words to use. If you don't, then you will come up with nothing.

BOSE - X. I have searched through every pink bulletin that is on the ais website, and found nothing. Sorry.

Thanks for your help, though - I will keep on searching, and when I find the correct page, I will print it out and give it to the CFI. I don't think that the confrontational method is best when it will be he doing the test.

Fuji Abound
29th Mar 2007, 14:15
I did try the search function, but didn't really come up with a satisfactory answer.

Here it is.

http://www.pprune.org/forums/showthread.php?t=213479&highlight=imc+minima

but don't quote rules as being from the CAA if they aren't.

Exactly - a bit pointless really.

An IMC only not in VERY current practice would be VERY stupid to attempt an approach beyond the 500/600ft recommendations In fact I would suggest even those are too low if you are not CURRENT.

Does it really matter what you have or havent - if you are not current, then dont do it, if you are current have your own minima and apply them. Same goes for an IR, aerobatics, you name it.

S-Works
29th Mar 2007, 14:28
Sorry Fuji what was the point of your statement?

Was the fact that the words VERY & CURRENT were in BLOCK CAPITALS not enough of an indication that I was refering to CURRENCY and not qualifications?

troddenmasses
29th Mar 2007, 14:29
Thank you all who have helped. I have finally found the passage that I'm interested in - AIP AD 1.1.2 It says:
3.3.2 IMC Rating holder in current practice
3.3.2.1 Pilots with a valid Instrument Meteorological Conditions (IMC) Rating are recommended to add 200ft to the minimum DH/MDH, but with absolute minima of 500ft for a precision approach and 600ft for a non-precision approach.


At least I have something to print out now to pop under the nose of the CFI to prove that it hasnt changed recently, as he told me.

IO540
29th Mar 2007, 14:42
Having spoken to countless instructors, I know for a fact that most of them don't know that an IMCR holder can legally fly to the minima published on the approach plate.

The mistaken belief that the +200ft / 500ft / 600ft / whatever is law is really widespread.

Of course the pilot needs to be current, and needs to be flying a suitably equipped plane, and this is where judgement has to come in. Not everything can be written down in black and white. But this is true for all IFR operations, not just flying some instrument approach. Flying an ILS down to 200ft, over flat as a pancake East Anglia, is a lot safer than flying say the NDB/DME 20 IAP into Shoreham down to its MDH of 800ft.

bookworm
29th Mar 2007, 14:51
The word that usually causes the difficulty in the AIP entry that you correctly quote is "absolute". It is tempting to interpret it as "mandatory, not recommended" but I believe that someone (IO540?) has a note from the CAA confirming the intention as "absolute, not relative to the minimum DH/MDH".

I find the use of absolute values rather strange. If you feel you need a cushion to avoid obstacles by more than the PANS-OPS margins, add a cushion. But it really doesn't matter what height above the threshold that corresponds to.

Fuji Abound
29th Mar 2007, 16:21
Sorry Bose - you are correct.

I know sometimes posters take pleasure in thinking IMCR holders as opposed to IR holders have to be in some way more current. I appreciate that was not your position and I am always conscious that with an IR I need to be current before flying to minima.

mark147
29th Mar 2007, 17:10
I find the use of absolute values rather strange. If you feel you need a cushion to avoid obstacles by more than the PANS-OPS margins, add a cushion. But it really doesn't matter what height above the threshold that corresponds to.I'd agree for a non-precision approach but following an ILS does get more and more tricky as you get closer to the threshold so I think the 500ft recommendation has some merit. I've no idea what the 600ft height is for though. Sounds like a committee meeting in which someone proposed the 500ft value and someone else said "and NPAs are less accurate so we should recommend a higher minimum for those"...

M.

bookworm
29th Mar 2007, 18:38
but following an ILS does get more and more tricky as you get closer to the threshold so I think the 500ft recommendation has some merit

Fair enough, but adding 200 ft to the ILS minimum DH results in a DH of at least 400 ft. Is that sooooo much harder to fly down to than 500 ft?!

englishal
30th Mar 2007, 07:38
An IMC only not in VERY current practice would be VERY stupid to attempt an approach beyond the 500/600ft recommendations In fact I would suggest even those are too low if you are not CURRENT.
You know what....I tend to disagree, seriously!;)

It doesn't matter how current you are, if you intercept the needles for an ILS and have a nice stabilized approach, keeping the needles centred, then any monkey can fly the approach. The difficult bit is knowing when to go missed and knowing that you have set everything else up properly (missed approach aids dialled in, brief for the missed, having a plan B!) and knowing when things are going wrong.

Believe it or not, instrument flying is not rocket science as some like to make out. I've held an IR since 2002 and there have been times when I have been "un-current", not legally but feeling. One thing I notice though is that the more instrument experience you have, the quicker currency comes back - a bit like riding a bike, if you're 40 years old and haven't ridden for 20 years, you'll feel a bit wobbly at first but not really dangerous, and it doesn't take long for it to come back. This equally applies to IR and IMCr holders......

Just my humble opionion of course.:)

S-Works
30th Mar 2007, 08:17
Your full of crap Al. You are just looking for a fight! ;)

Knowing when to make the Missed Call, setup and IDENT the aids is just as much a part of CURRENCY as being able to keep the needles centred or the correct rate of descent for a Non Prec.

You are right, Instrument flight is not rocket science and is in fact easier than VFR flight. But it relies on Currency to do it safely regardless of the rating printed on your license and at no point did a single out any rating. My comment was about currency nothing else.

Fright Level
30th Mar 2007, 09:52
I understood that cloud base is not the main factor in determinining approach limits, but that it is the visibility. The problem with the IMC combo of 1800m and 400/500 feet is that on a 3 degree slope, at 500 feet, you'll still be almost two miles from touchdown in a vis of a mile, so at the limits, you may end up throwing away a perfectly legal approach simply because you can't see the runway until you get a little further along.

In practise, it may be better to confirm sight of the ground at 500' then continue down the GS a little further until the runway comes into sight. Of course a decent CAT2/3 lighting system at the airfield helps greatly as the approach lights will easily be seen at 500' even if the runway isn't.
I've taken a couple of PPL/IMC mates in the sim and frozen it right on their limits to show them how murky it still looks at 500' but that within another 10-20 seconds on the approach, the whole picture changes and the warm fuzzy feeling follows.

IO540
30th Mar 2007, 10:07
In practice the 1800m viz requirement is not a problem. I don't recall it ever being a problem in 5 years.

This may be because viz is rarely that bad. 1800m is serious haze/mist and in those conditions one tends to not have a cloudbase problem. 3000m is common (like today) but 1800m is not common.

The biggest problem is cloudbase below the MDH or DH. Much of the UK is not flyable because of this, much of the year, and that includes most airfields with an IAP too. Only an ILS really cracks it.

englishal
30th Mar 2007, 13:39
Your full of crap Al. You are just looking for a fight!
;)
Heck, just stick the AP into approach mode and fly it on the AP. That is always current:} 50' pull the power and watch George flare for you.....easy:O

Fuji Abound
30th Mar 2007, 22:11
The real problem for the IMCR holder is that usually the approaches flown during training are not to the tolerance required for an IR. Therefore an IMCR holder must develop his skills in line with his "willingness" to accept lower minima. If he does so in a controlled way he will achieve the same skill level as a newly minted IR holder, if he does not, he will need quicker reactions and a steady hand the first time he becomes visual after an approach to near minima.

rich poole
15th Nov 2007, 17:39
Hi, had a quick search and havenít found anything on the topic but basically Iím on a structured modular course and as part of our hours building weíve been given the chance to do an IMC rating. As I will be going onto gain and IR etc is it necessary to do the IMC? I can see that the IMC would give u an advantage going into the IR but would the 15hours of dual be better spent on P1 time?

Thanks for the advice in advance
Rich

IO540
15th Nov 2007, 18:55
At a guess, an IMCR will give you single crew IFR privileges in UK airspace Classes D,E,F,G whereas your multi crew JAA ATPL will give you no single crew IFR privileges whatsoever.

Whether, once you have your ATPL, you could knock off a quick IR checkride in some piston twin to get a single crew ME IR (which is way better than an IMCR because it gives you worldwide IFR privileges in any JAA-reg single crew SE or ME plane) in less time, is a good question.

An IMCR is rarely done in 15hrs to the required standard. 25 is more like it.

Cobalt
15th Nov 2007, 19:38
rich,

worst case, the IMC rating will make you a very bored student as you struggle to fill the sim hours for your IR with sensible things to do.... ;)

If you don't mind spending an additional 1000-1500 pounds during hourbuilding (for better equipped a/c, instructor, test, and fees) I would do it, but you won't get full payback in saved IR hours because of the minimum 55 hours (no credit).

Re hours - you need 200 TT and 100 PIC, so unless you already used 80 for your PPL and night qualification that is not a factor. Don't think the 15 hours PIC will set you apart from other "low hours" candidates after CPL/IR.

Ah, one more thing - I would recommend doing the IMC rating with proper screens or at very least a hood, not foggles. Screens give the most realistic "IMC" experience, foggles make things far too easy. Hood is halfway in between if you don't cheat.

S-Works
15th Nov 2007, 19:56
If he does the hours with an IRI at his commercial school as if they were towards the IR he can get an IMC when he meets the standard and the hours will still count towards the IR as long as they are completed within the the appropriate time frame etc.

NorthSouth
16th Nov 2007, 08:00
IO540:an IMCR will give you single crew IFR privileges in UK airspace Classes D,E,F,G whereas your multi crew JAA ATPL will give you no single crew IFR privileges whatsoeverSurely that's not right? The guy's on a "structured modular course". That presumably means he will be doing a CPL followed by a ME IR on a single-crew piston twin. Therefore his IR when he gets it will give him all the single crew IFR privileges you can get. He won't lose those until that rating lapses because he doesn't do his annual route sectors etc. That MIGHT be because he's only then flying multi-crew aircraft, but might be because he's flying nothing, or only singles. And in any case he won't get an ATPL until he has 1500 hours and a type rating on a multi-crew type. Until that point his flying is done on a CPL.
NS

rich poole
16th Nov 2007, 15:54
Thanks very much for the advice, does seem a lot more sensible to spend the time constructively.
Rich

Three Yellows
18th Nov 2007, 22:06
Bose-X said:
Your full of crap Al. You are just looking for a fight!

and you're not then Bose-X?

The timetable is this summer. We are working on the changes now with a submission for june.

(Re: The "new IR")