IMC or VMC?
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IMC or VMC?
Scenario:
- IFR Flight Plan
- CTR and airport Class C airspace
- Shooting ILS
- Ceiling OVC 015
- Shooting ILS stablished
At 1500ft on the ILS I breakout of clouds and see the airport clearly.
The airport according to those condition is VMC and VFR.
To say I am VMC in class C airspace I need to be 1000ft below clouds.
Am I VMC or IMC? (My guess is IMC)
Isn't it strange to say I am IMC in that situation when a guy is on the traffic pattern doing touch and goes VFR VMC?
Thanks!
- IFR Flight Plan
- CTR and airport Class C airspace
- Shooting ILS
- Ceiling OVC 015
- Shooting ILS stablished
At 1500ft on the ILS I breakout of clouds and see the airport clearly.
The airport according to those condition is VMC and VFR.
To say I am VMC in class C airspace I need to be 1000ft below clouds.
Am I VMC or IMC? (My guess is IMC)
Isn't it strange to say I am IMC in that situation when a guy is on the traffic pattern doing touch and goes VFR VMC?
Thanks!
Last edited by konde_landi; 22nd Oct 2013 at 02:17.
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You are still IMC, you are however visual. you could only be VMC 1000ft clear of cloud which is going to happen somewhere near your overshoot (so its nigh on useless)
The guy busting out some circuits might be doing it special VFR or simply over estimating the cloud base.
The guy busting out some circuits might be doing it special VFR or simply over estimating the cloud base.
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The VFR minimum in class C airspace is 1500ft so he was perfectly fine doing circuits VFR. If the Cloud base was 1400ft he would require a special VFR clearance.
The IFR arrival and the circuit basher would be separated geographically. The IFR arrival reports established on the Localiser and the circuit traffic sighted or reported on downwind, I'm sure he would not be turned be base in front of the arrival unless the ATCO felt this would be safe. In other words the arrival is far enough out on the localiser for this to work. If not just orbit on downwind or at a VRP nearby until he can be fitted in behind No. 2.
Outside Class C I'm not sure.
The IFR arrival and the circuit basher would be separated geographically. The IFR arrival reports established on the Localiser and the circuit traffic sighted or reported on downwind, I'm sure he would not be turned be base in front of the arrival unless the ATCO felt this would be safe. In other words the arrival is far enough out on the localiser for this to work. If not just orbit on downwind or at a VRP nearby until he can be fitted in behind No. 2.
Outside Class C I'm not sure.
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@LookingForAJob
regardless of what Sky Conductor wrote... I'm interested to find the para' from ICAO docs, where "geographical separation" (most probably - By reference to the same or different geographic locations) is mentioned in connection with "local procedures" or "deemed separations" or "local rules".
regardless of what Sky Conductor wrote... I'm interested to find the para' from ICAO docs, where "geographical separation" (most probably - By reference to the same or different geographic locations) is mentioned in connection with "local procedures" or "deemed separations" or "local rules".
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As LookingForAJob has mentioned, it depends on the respective national rules of the air. As far as SARPs are concerned, you'd be in VMC.
According to the definition in ICAO Annex 2, Chapter 1 visual meteorological conditions are 'meteorological conditions expressed in terms of visibility, distance from cloud, and ceiling, equal to or better than specified minima' and, according to the note following the definition, the 'specified minima are contained in Chapter 4.'
Since you are on approach, the minima of 4.2 of Chapter 4 apply. These are 1) ceiling 1500 ft or higher and 2) ground visibility 5 km or higher. Since both ceiling and visibility are better than the prescribed minima, you are by definition in VMC.
According to the definition in ICAO Annex 2, Chapter 1 visual meteorological conditions are 'meteorological conditions expressed in terms of visibility, distance from cloud, and ceiling, equal to or better than specified minima' and, according to the note following the definition, the 'specified minima are contained in Chapter 4.'
Since you are on approach, the minima of 4.2 of Chapter 4 apply. These are 1) ceiling 1500 ft or higher and 2) ground visibility 5 km or higher. Since both ceiling and visibility are better than the prescribed minima, you are by definition in VMC.
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Don't get me wrong LFAJob, I understand and partially agree, especially on the last words regarding murky days...
The only thing is, that PANS-ATM added another little thing...
Note. - In the minima specified in 5.4.1.2 an appropriate buffer has already been included.
And 5.4.1.2.1.1 is a sub-para... There's also a figure.
The only thing is, that PANS-ATM added another little thing...
Note. - In the minima specified in 5.4.1.2 an appropriate buffer has already been included.
And 5.4.1.2.1.1 is a sub-para... There's also a figure.
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At 1500ft on the ILS I breakout of clouds and see the airport clearly.
The airport according to those condition is VMC and VFR.
To say I am VMC in class C airspace I need to be 1000ft below clouds.
The airport according to those condition is VMC and VFR.
To say I am VMC in class C airspace I need to be 1000ft below clouds.
Logically, if you are below cloud and everything below you, between you and the ground with nothing in the way - such as cloud - and you are intending to continue downwards, then - you could cancel IFR (if during the remainder of the approach you were unlikely to go IMC again - but if you had to do a go-around procedure involving climbing back into the murk then you would have to be IFR as you may soon become IMC.
In answer to your question - you were most definately - VMC, which is a condition.
and you were, or rapidly becoming VFR - I do not think anyone will write about you in this case, nor do you need worry. If you had not cancelled your IFR then you were still IFR and yet, unmistakenly, irrevocably and quintessentially V.M.C
IMC - can`t see a
thing! Conditions out of the window (which is why you are on instruments).VMC - can see everything. Conditions out of the window
IFR - IFRules.
VFR - VFRules.
Conditions
Rules
Last edited by Natstrackalpha; 28th Oct 2013 at 12:57.
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Nats, I think a quick look at the definition of IMC and Annex 2 might be in order.
Am I VMC or IMC? (My guess is IMC)
ed that one up too?I fully appreciate that the members of EASA have not got much experience or knowledge and cannot possibly know the difference between the back and the pointy end of an aeroplane nor would they have the je ne sais whotsit to realise the distinct difference between VMC and VFR.
>
>
I appreciate the work you have put in here and the work that you do. I am not being funny - I am merely suggesting (at this juncture) that "they" have probably made a silly rule which makes this simple difference between VMC and VFR opaque, like mashed potato.
I still maintain that there is a difference between a Rule like . . . . Visual Flight Rule(s) and [what you see out the window] Conditions, like: Visual Meteorological Conditions.
>
Please, I was with a bunch of CAA Examiners once and we were flying around in a circle whilst they tried to decide what to do next. We could see clearly out of the window and ISOS but the clouds were all around us and although broken were not more than 20 or 50 feet away from the aircraft and I whinged because we were not under +ive Radar Control and only had a basic service - and, any old aeroplane without a radio could have come our way unannounced and hit us. So here, we were definately IMC - even if we could see out of the window.
The OP said he was visual with the airport and the ground below, also strongly suggesting that there was nothing between him and the airport in the way of cloud - it looks like good Victor Mike below to me . . . VMC below cloud. Albeit if not VFR.
Last edited by Natstrackalpha; 2nd Nov 2013 at 20:31.
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It is no doubt that in the situation the OP described, the aircraft was in IMC.
What I don't understand is the rationale for 1000 ft vertical distance to cloud in class C airspace.
In class B airspace, there are no cloud distance requirements for VMC -- only "clear of cloud" and a flight visibility requirement. That makes sense as all traffic is separated by ATC.
In class C airspace, there is no VFR-VFR separation so the requirement of 1500 m horizontal distance to cloud makes some sense as (e.g.) otherwise two VFR flights could fly along opposite sides of the same cloud at zero horizontal distance and eventually collide.
But in class C IFR is separated from VFR so no IFR flight could descend out of cloud and hit someone flying VFR.
Or are there cases I haven't thought of?
What I don't understand is the rationale for 1000 ft vertical distance to cloud in class C airspace.
In class B airspace, there are no cloud distance requirements for VMC -- only "clear of cloud" and a flight visibility requirement. That makes sense as all traffic is separated by ATC.
In class C airspace, there is no VFR-VFR separation so the requirement of 1500 m horizontal distance to cloud makes some sense as (e.g.) otherwise two VFR flights could fly along opposite sides of the same cloud at zero horizontal distance and eventually collide.
But in class C IFR is separated from VFR so no IFR flight could descend out of cloud and hit someone flying VFR.
Or are there cases I haven't thought of?
