Low Cloud
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Nobody has mentioned yet the missed approach height for imc rated approaches, these may well be above the actual cloudbase your flying around in.One thing I have had to do in the past is approach imc somewhere with an atc and half decent minimum approach height then skim in under the clag to get home.
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Nobody has mentioned yet the missed approach height for imc rated approaches, these may well be above the actual cloudbase your flying around in.One thing I have had to do in the past is approach imc somewhere with an atc and half decent minimum approach height then skim in under the clag to get home.
If you arrive IFR and go missed, then you have to fly the published missed approach.
If you got visual before DA/MDA why didn't you land?
If for whatever reason you went missed and doing so you are still (or again) in IMC then you have to either fly another approach (as published) or divert, as per the normal rules.
You do not go missed on an IFR approach and then duck down off the published missed approach procedure to get below cloud again, to fly somewhere visually!! The missed approach procedure is designed to avoid terrain and if you do "your own thing" off it you might well hit something.
One cannot do IFR ad hoc. One has to either fly VFR (that means being visual) or fly IFR (which means you may or may not be in IMC). The planning is quite different for the two.
There is no such thing as an "IMC rated approach". An approach is flown as published.
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some airports will allow you and help you to descend imc and then resume your own navigation before being on final approach. I did not mean that you can be on approach and then bail out and apologise for being misleading.
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Cloud seldom "switches on or off" at defined heights. You gradually (or suddenly) loose forward vision. What rod1 said is technically correct but I am sure he didn't recommend it. Sorry for butting in rod.
DO
DO
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some airports will allow you and help you to descend imc and then resume your own navigation before being on final approach.
But "before being on final approach" is not really correct because it is from the final approach track that one normally breaks off when visual.
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some airports will allow you and help you to descend imc and then resume your own navigation before being on final approach.
At an airport with a procedure you could fly the procedure and once established VMC ask to terminate the procedure and continue to make a visual approach or break off the approach completely and depart en route. With the consent of AT I see no reason why you should not do so at any point in the procedure. For example if you arrive in the hold in IMC at 3,000 and descend in the hold to 2,000 at which point you become visual and request to break off the procedure with consent I do not see an issue. This might for example prove a useful means of making a let down whilst ensuring adequate terrain clearance and in theory seperation from en route traffic.
That aside I dont see how else AT could "allow or help you" with a descent from to IMC to VMC - for example if you were to arrive in the overhead of an airport without a procedure in IMC and descend in their overhead they are not in a position to "guarantee" any terrain seperation or seperation from other traffic any more or less than en route.
It amy be true that they will have a better idea what traffic there is below the cloudbase than you might en route (assuming you cant receive a RIS and non transpoding en route traffic beside) and it may also be true that you know very specifically where you are and therefore what terrain implications exist but you are now involved in a "home made" letdown with all the risk involved in doing so.
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“you said 1ft under a thick overcast was ok, does that mean then that cloud seperation doesn`t apply to what is above you?”
No! The VFR rule I was demonstrating is;
At or below 3000 ft, 140kn or less, clear of cloud and in sight of the surface, Min 3km vis.
If you fly at 3000ft and 140kn, you can see some ground below, the vis is 3km but there is a solid overcast directly above you then you are VMC. There is no “500ft from cloud” rule. I am not suggesting this is a good idea as you have lost any hope of see and avoid if some chancer is descending through cloud with no radar service and not talking to anyone then you could be in deep dodo, but that is admittedly statistically unlikely.
It is also fine to fly at 3000ft with a broken layer of cloud below you, provided you keep the above rule in mind. It is often possible to carry out long Xcountry flights in quite poor weather and remain totally legal by using the above rule. It is however vital that you have the skill and the equipment to get you out of trouble if the weather gets unexpectedly bad.
I recently toured Scotland from the midlands on a weekend when the vis was 3k but there was NSW and nil wind. I had to use VOR to backup the nav, but again this is perfectly ok. I have also configured my aircraft so its normal cruse speed is 138kn, so I do not get a speeding ticket!
Rod1
No! The VFR rule I was demonstrating is;
At or below 3000 ft, 140kn or less, clear of cloud and in sight of the surface, Min 3km vis.
If you fly at 3000ft and 140kn, you can see some ground below, the vis is 3km but there is a solid overcast directly above you then you are VMC. There is no “500ft from cloud” rule. I am not suggesting this is a good idea as you have lost any hope of see and avoid if some chancer is descending through cloud with no radar service and not talking to anyone then you could be in deep dodo, but that is admittedly statistically unlikely.
It is also fine to fly at 3000ft with a broken layer of cloud below you, provided you keep the above rule in mind. It is often possible to carry out long Xcountry flights in quite poor weather and remain totally legal by using the above rule. It is however vital that you have the skill and the equipment to get you out of trouble if the weather gets unexpectedly bad.
I recently toured Scotland from the midlands on a weekend when the vis was 3k but there was NSW and nil wind. I had to use VOR to backup the nav, but again this is perfectly ok. I have also configured my aircraft so its normal cruse speed is 138kn, so I do not get a speeding ticket!
Rod1
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At an airport with a procedure you could fly the procedure and once established VMC ask to terminate the procedure and continue to make a visual approach or break off the approach completely and depart en route. With the consent of AT I see no reason why you should not do so at any point in the procedure.
It is relatively common for a radar equipped controller to vector aircraft to intercept an extended final approach course and descend you to their minimum vectoring altitude, at which point hopefully you are right at/under the cloud base and can see ground straight underneath you and make the couple of foot descent into VMC. This is a reasonably sensible approach when the cloud base is around 1000-1200 ft AGL
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if some chancer is descending through cloud with no radar service
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mm flynn
Look at where meiklepap stays and have a look at the chart or the MDA at the few fields with radar.
I would be surprised if there was one with an MDA below 4500ft.
Come to think of it did this not start as a low level VFR question?
DO
Look at where meiklepap stays and have a look at the chart or the MDA at the few fields with radar.
I would be surprised if there was one with an MDA below 4500ft.
Come to think of it did this not start as a low level VFR question?
DO
Last edited by dont overfil; 6th Jun 2008 at 17:03.
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All of them have MDA's less than 4500. I expect you meant MSA - which goes out 25 miles or grid MEA which covers a large distance as well. The fields I looked at all seem to have Minimum Vectoring altitudes at or near the platform altitude of the approach. But, as you say this was a VFR question.
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mm flynn
You are of course correct. I really should not do this at work, half the brain is elsewhere.
The point I was trying to make is you can't go far in Scotland at 1000ft
do.
You are of course correct. I really should not do this at work, half the brain is elsewhere.
The point I was trying to make is you can't go far in Scotland at 1000ft
do.
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“Thread drift... Rod , you mean that you could make the MCR01 go even faster than 138kts if you wanted to? Seriously impressive....”
The short answer is yes, but it is not as simple as that…
There are no figures on how to set up my kit built C/S prop on my airframe. This means I have to adjust and test, adjust and test. I have the fine pitch stop where I want it but the coarse pitch stop is too fine to achieve best performance, especially at altitude. In order to adjust and test I need a day, which is very smooth (no nasty bumps), as the aircraft does 152kn TAS (3000ft) flat out, and if I move the coarse pitch stop it will go faster (by an unknown amount). This brings up the other problem, the VNE is 162kn, which is ok, but the rough air speed is 128kn. There are certainly conditions, say above a broken layer, or on a still evening when it would be perfectly safe to cruse at 140kn plus, but it has its down sides.
My aircraft is an MCR01 Club, which has a bigger wing than an MCR01 Sportster. A well sorted sportster will cruse at 160kn (but has 30kg less useful load and needs more runway). To do this it uses a special “high speed” blade on the PV50 prop hub. I have the standard blades, but am now getting into the speed band where the “high speed” blades would be more efficient. There is no danger of my blades failing, but I am loosing performance. The importer would love to see what would happen if I fitted the high speed blades, but unless he loans me £700 worth of blades to try I am unlikely to find out!!
I am also getting 15lph (mogas) and I suspect that getting an extra 7 or 8kn would push the fuel burn up to 18lph+. I will probably have another play at some point, but I am having too much fun flying her long distance to go back to development right now. Over the winter I may upgrade the glass HSI to a full “synthetic vision” big screen system and maybe tweak the prop some more as well or I may just keep flying her as much as possible…
Rod1
The short answer is yes, but it is not as simple as that…
There are no figures on how to set up my kit built C/S prop on my airframe. This means I have to adjust and test, adjust and test. I have the fine pitch stop where I want it but the coarse pitch stop is too fine to achieve best performance, especially at altitude. In order to adjust and test I need a day, which is very smooth (no nasty bumps), as the aircraft does 152kn TAS (3000ft) flat out, and if I move the coarse pitch stop it will go faster (by an unknown amount). This brings up the other problem, the VNE is 162kn, which is ok, but the rough air speed is 128kn. There are certainly conditions, say above a broken layer, or on a still evening when it would be perfectly safe to cruse at 140kn plus, but it has its down sides.
My aircraft is an MCR01 Club, which has a bigger wing than an MCR01 Sportster. A well sorted sportster will cruse at 160kn (but has 30kg less useful load and needs more runway). To do this it uses a special “high speed” blade on the PV50 prop hub. I have the standard blades, but am now getting into the speed band where the “high speed” blades would be more efficient. There is no danger of my blades failing, but I am loosing performance. The importer would love to see what would happen if I fitted the high speed blades, but unless he loans me £700 worth of blades to try I am unlikely to find out!!
I am also getting 15lph (mogas) and I suspect that getting an extra 7 or 8kn would push the fuel burn up to 18lph+. I will probably have another play at some point, but I am having too much fun flying her long distance to go back to development right now. Over the winter I may upgrade the glass HSI to a full “synthetic vision” big screen system and maybe tweak the prop some more as well or I may just keep flying her as much as possible…
Rod1
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Apart from being able to carry full fuel , 6 people and the kitchen sink ( none of which I ever do) I have to wonder why I put up with chugging along at a stately 135 kts at 18 gals an hour in a C206. I am gonna have to get me one of these plastic fantastics methinks......
PPL limited to VFR?
A number of comments have incorrectly stated that the holder of a PPL is restricted to VFR flight only. This is not strictly correct. The UK PPL(A) and JAA FCL PPLs allow flight in IMC in class G airspace as long as the pilot can still see the ground and maintains the specified flight visibility. (I,e the vertical and horizontal distances from cloud do not apply.) The NPPL does require the pilot to remain VFR at all times.
Where is this info? The Air Navigation Order - part of which is appended.
ANO Jan 2008 (CAP
PPL (A) & JAA FCL PPL
c) unless his licence includes an instrument rating (aeroplane) or an instrument
meteorological conditions rating (aeroplanes), fly as pilot in command of such an
aeroplane:
(i) on a flight outside controlled airspace when the flight visibility is less than
3 km;
(ii) on a special VFR flight in a control zone in a flight visibility of less than 10
km except on a route or in an aerodrome traffic zone notified for the
purpose of this sub-paragraph; or
(iii) out of sight of the surface;
(e) unless his licence includes an instrument rating (aeroplane), fly as pilot in
command or co-pilot of such an aeroplane flying in Class A, B or C airspace in
circumstances which require compliance with the Instrument Flight Rules;
(f) unless his licence includes an instrument rating (aeroplane) or an instrument
meteorological conditions rating (aeroplanes), fly as pilot in command or co-pilot
of such an aeroplane flying in Class D or E airspace in circumstances which
require compliance with the Instrument Flight Rules; or
NPPL
(5) He shall not fly:
(a) as pilot in command of such a SSEA on a flight outside controlled airspace when
the flight visibility is less than 5 km;
(b) as pilot in command of such a SLMG or microlight aeroplane on a flight outside
controlled airspace when the flight visibility is less than 3 km.
(c) as pilot in command of any such aeroplane:
(i) on a special VFR flight in a control zone in a flight visibility of less than 10
km;
(ii) out of sight of the surface; or
(iii) at night; or
(d) as pilot in command of any such an aeroplane in circumstances which require
compliance with the Instrument Flight Rules.
Where is this info? The Air Navigation Order - part of which is appended.
ANO Jan 2008 (CAP
PPL (A) & JAA FCL PPL
c) unless his licence includes an instrument rating (aeroplane) or an instrument
meteorological conditions rating (aeroplanes), fly as pilot in command of such an
aeroplane:
(i) on a flight outside controlled airspace when the flight visibility is less than
3 km;
(ii) on a special VFR flight in a control zone in a flight visibility of less than 10
km except on a route or in an aerodrome traffic zone notified for the
purpose of this sub-paragraph; or
(iii) out of sight of the surface;
(e) unless his licence includes an instrument rating (aeroplane), fly as pilot in
command or co-pilot of such an aeroplane flying in Class A, B or C airspace in
circumstances which require compliance with the Instrument Flight Rules;
(f) unless his licence includes an instrument rating (aeroplane) or an instrument
meteorological conditions rating (aeroplanes), fly as pilot in command or co-pilot
of such an aeroplane flying in Class D or E airspace in circumstances which
require compliance with the Instrument Flight Rules; or
NPPL
(5) He shall not fly:
(a) as pilot in command of such a SSEA on a flight outside controlled airspace when
the flight visibility is less than 5 km;
(b) as pilot in command of such a SLMG or microlight aeroplane on a flight outside
controlled airspace when the flight visibility is less than 3 km.
(c) as pilot in command of any such aeroplane:
(i) on a special VFR flight in a control zone in a flight visibility of less than 10
km;
(ii) out of sight of the surface; or
(iii) at night; or
(d) as pilot in command of any such an aeroplane in circumstances which require
compliance with the Instrument Flight Rules.
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Last time I read up on all this I came to the conclusion that a JAA PPL may not fly in IMC, but a CAA PPL may (there being one tiny little difference between the definition of IMC and the weather limitations on the CAA PPL, forget what the detail was now but it was weather conditions in which I wouldn't be flying anyway).