IFR cruising altitude below LSALT in day VMC
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Me thinks Icarus53 didn't RTFQ.
Time to get back to the books!
AIP ENR 1.5 (Jep Terminal section) only applies to Holding, Instrument Approach and Departure procedures.
The visual approach requirement listed in ENR 1.5 describes a situation in which an aircraft is not in VMC but allows a visual based approach. The aircraft is clear of cloud but may not have minimum VMC visibility or distance from cloud requirements and therefor is still in IMC.
If an IFR aircraft is in VMC by day it may operate at any appropriate IFR cruise level, below LSALT/MSA if it wishes. It still operates to IFR procedures, which if there is no stress of weather means normal Low Flying rules (CAR 157) and circuit joining procedures. The only time it need be operated to a VFR procedure is if navigating by visual reference to ground or water (which is perfectly legal for an IFR aircraft to do in VMC) then it must apply the position fixing requirements as required (ENR 1.1 19).
The visual approach requirement listed in ENR 1.5 describes a situation in which an aircraft is not in VMC but allows a visual based approach. The aircraft is clear of cloud but may not have minimum VMC visibility or distance from cloud requirements and therefor is still in IMC.
If an IFR aircraft is in VMC by day it may operate at any appropriate IFR cruise level, below LSALT/MSA if it wishes. It still operates to IFR procedures, which if there is no stress of weather means normal Low Flying rules (CAR 157) and circuit joining procedures. The only time it need be operated to a VFR procedure is if navigating by visual reference to ground or water (which is perfectly legal for an IFR aircraft to do in VMC) then it must apply the position fixing requirements as required (ENR 1.1 19).
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Gents, whilst we are on the subject can anyone point me to the reference which proves I can descend below the route LSALT once I have fixed myself past a critical obstacle en route? (The IFR case not the night VFR case) My thoughts are that if I draw the splay on a topo map, calculate the LSALT IAW gen 3.3 then re calculate it without the obsticle (ie I have positively fixed myself past it), that would then be my new LSALT for the remainder of the route 
It makes sense and could give you an operational advantage but I just can't find a bloody reference to confirm my thoughts. Lets also say it's not day VMC either.
cheers
It makes sense and could give you an operational advantage but I just can't find a bloody reference to confirm my thoughts. Lets also say it's not day VMC either.cheers
There is no such rule under australian regulations in reference to IFR, NVFR has an option to replan LSALTS when visually passed critical obstacles in flight (AIP GEN 3.3/3.10), IFR may not. The LSALT is valid for the route segment, if one is published it must be used, if not than one must be calculated fron point to point (segment) using the approved method.
In preflight planning you could vary your flight path to approach over lower terrain and specify fixes, calculate segment LSALTS and so on. The fixes must comply with IFR navigation & position fixing requirements.
Again CAR 178 is quite clear regarding IFR minimum altitude requirements.
In preflight planning you could vary your flight path to approach over lower terrain and specify fixes, calculate segment LSALTS and so on. The fixes must comply with IFR navigation & position fixing requirements.
Again CAR 178 is quite clear regarding IFR minimum altitude requirements.
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slow n low
You could just 'invent' a point (radial and range or GPS position) en route and abeam said obstacle and begin calculating a new LSALT splay from this point. Just mark the point of your flight plan, report at it as required, and once through that point (visual, GPS or DME range/bearing) the new LSALT is valid.
You could just 'invent' a point (radial and range or GPS position) en route and abeam said obstacle and begin calculating a new LSALT splay from this point. Just mark the point of your flight plan, report at it as required, and once through that point (visual, GPS or DME range/bearing) the new LSALT is valid.
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you need an excuse
My thinking process when learning and applying IFR height requirements has always been "you need an excuse to be where you are" (in altitude).
So anywhere along your flight you should be able to ask yourself "am I allowed to be here" and the answer hopefully will be something like:
- yes I'm above the route LSALT, or
- yes I'm established within 25nm and above the MSA,or
- yes I'm within the circling area, or
- yes I'm above the relevant DME step (also handy to apply in reverse on departure)
- etc etc
If you can't think of an excuse straight away then you had better be in day VMC which is your last option. There are no loopholes in IFR requirements, smarter people than us would have found them by now and punched themselves into a hill somewhere.
So anywhere along your flight you should be able to ask yourself "am I allowed to be here" and the answer hopefully will be something like:
- yes I'm above the route LSALT, or
- yes I'm established within 25nm and above the MSA,or
- yes I'm within the circling area, or
- yes I'm above the relevant DME step (also handy to apply in reverse on departure)
- etc etc
If you can't think of an excuse straight away then you had better be in day VMC which is your last option. There are no loopholes in IFR requirements, smarter people than us would have found them by now and punched themselves into a hill somewhere.
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Thanks all, just getting prep in for when the QFI plays the "what if" game 
(damn instructors...) The intermediate point sounds like a fair and valid option
Cheers
(damn instructors...) The intermediate point sounds like a fair and valid optionCheers
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For the military gent earlier in the post - IFR is a civilian concept adopted by the military but subject to military adjustments.
If you fly below the LSALT in peacetime then I'm sure it is only because your military airplane has a navigation system capable of much finer tolerances that the average C402 in "beacon crawl" mode. I'm thinking F111 with TFR and P3 with search radar. These airplanes are IFR for flight planning purposes but how they fly is authorized by the RAAF not CASA. During wartime I'm sure prosecuting the mission would take precedence over weather conditions but once again you're not flying spitfires and B17's anymore.
Civilian pilots always fly visually (not VFR) on departure even if it is only the 300 metres visibility dispensation they and the aircraft have; and unless they are CAT 3C qualified always finish the flight with at a minimum view of the runway from 200 feet and 550 metres! A visual approach is defined as an IFR procedure to get around separation and procedure change issues but you are still flying below the LSALT using your eyeballs for navigation. A visual departure can be conducted by day in VMC, but not at night.
To go back to the original question. There is nothing to stop our pprune colleague from departing IFR, flying visually en-route then recovering from above the LSALT on an instrument approach. But if he flies visually on departure, visually en-route and visually on arrival and landing, at no stage has he flown under the IFR even if he puts it on his flight plan.
If you fly below the LSALT in peacetime then I'm sure it is only because your military airplane has a navigation system capable of much finer tolerances that the average C402 in "beacon crawl" mode. I'm thinking F111 with TFR and P3 with search radar. These airplanes are IFR for flight planning purposes but how they fly is authorized by the RAAF not CASA. During wartime I'm sure prosecuting the mission would take precedence over weather conditions but once again you're not flying spitfires and B17's anymore.
Civilian pilots always fly visually (not VFR) on departure even if it is only the 300 metres visibility dispensation they and the aircraft have; and unless they are CAT 3C qualified always finish the flight with at a minimum view of the runway from 200 feet and 550 metres! A visual approach is defined as an IFR procedure to get around separation and procedure change issues but you are still flying below the LSALT using your eyeballs for navigation. A visual departure can be conducted by day in VMC, but not at night.
To go back to the original question. There is nothing to stop our pprune colleague from departing IFR, flying visually en-route then recovering from above the LSALT on an instrument approach. But if he flies visually on departure, visually en-route and visually on arrival and landing, at no stage has he flown under the IFR even if he puts it on his flight plan.
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Mr Approach
So by your reckoning a RPT flight flown entirely visually on departure, visually en-route and visually on arrival and landing would not have operated under the IFR? I think not. IFR is a set of procedures not a flight condition.
Also operating at low level IFR requires no extra kit if done visually
. Still IFR but VMC
But if he flies visually on departure, visually en-route and visually on arrival and landing, at no stage has he flown under the IFR even if he puts it on his flight plan.
Also operating at low level IFR requires no extra kit if done visually
. Still IFR but VMC
But if he flies visually on departure, visually en-route and visually on arrival and landing, at no stage has he flown under the IFR even if he puts it on his flight plan.
Thread Starter
Sorry for the late reply. Been away on a charter.
Now, it appears that the consensus of opinion, as well as my view, is that, it IS permissible to cruise below LSALT in day VMC when operating IFR between two non towered aerodromes 40 NM apart.
To diverge slightly and without knowing all the particular RPT/Company procedures, but when my mates join the airlines, they say that when cleared to descend into a non towered aerodrome, say Dubbo, even on a "blue sky" day, that they must set LSALT in the Altitude Selector and wait until 30 NM before setting circuit altitude.
Why can't they set circuit altitude in the first place?
Anyone know?
Now, it appears that the consensus of opinion, as well as my view, is that, it IS permissible to cruise below LSALT in day VMC when operating IFR between two non towered aerodromes 40 NM apart.
To diverge slightly and without knowing all the particular RPT/Company procedures, but when my mates join the airlines, they say that when cleared to descend into a non towered aerodrome, say Dubbo, even on a "blue sky" day, that they must set LSALT in the Altitude Selector and wait until 30 NM before setting circuit altitude.
Why can't they set circuit altitude in the first place?
Anyone know?
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Years ago I was taught that you could submit an IFR plan and on any particular leg, if you wanted to, you could in the remarks on the right of the plan nominate VFR for that leg, thus fly a VFR leg on an IFR plan. Dd it many times, especially on a last short leg to get home. Not that hard really. Or you could, in flight, just cancel IFR and fly the last bit visual. Again not hard.
A flight is either IFR or VFR, the pilot must nominate which rules he is undertaking as among other things the SAR and Traffic alerting are completely different. It is possible to show on a plan notification a change to VFR at a point enroute. However this then makes the plan and flight from this point VFR only, this is usually done to avoid IFR alternate requirements.
Setting LSALT/MSA on descent is just an SOP which is done as a routine to avoid descent in IMC below a critical altitude (do it all the time and you don't forget when it counts). It is possible and happens often on certain short routes that IFR RPT aircraft may fly below route LSALT during the day in good weather (VMC).
As has been stated many times before IFR = Instrument Flight Rules, a pilot flying on an IFR plan in VMC is still operating under the IFR. The pilot does not need to look at his insturments at all in VMC, navigation could be solely with reference to a WAC/VTC and ground features and it would still be under the IFR and legal in VMC.
Setting LSALT/MSA on descent is just an SOP which is done as a routine to avoid descent in IMC below a critical altitude (do it all the time and you don't forget when it counts). It is possible and happens often on certain short routes that IFR RPT aircraft may fly below route LSALT during the day in good weather (VMC).
As has been stated many times before IFR = Instrument Flight Rules, a pilot flying on an IFR plan in VMC is still operating under the IFR. The pilot does not need to look at his insturments at all in VMC, navigation could be solely with reference to a WAC/VTC and ground features and it would still be under the IFR and legal in VMC.
bb744,
You could do that, in the GOD's. Not so sure what happens now?
Just submit an IFR flightplan, and nominate VFR or NVMC procedures for certain legs!
Eg. Before there were navaids at YBMC, you would submit an IFR plan. But you would plan VFR Procedures from Nambour VOR (being the last available navaid) to Maroochy airport. That way, when you became visual, you didn't have to gin around at the LSALT!
In the example GBO gives, you could submit an IFR plan, an nominate VFR procedures for the leg out and back!
How do I remember that sh!t ?
You could do that, in the GOD's. Not so sure what happens now?
Just submit an IFR flightplan, and nominate VFR or NVMC procedures for certain legs!
Eg. Before there were navaids at YBMC, you would submit an IFR plan. But you would plan VFR Procedures from Nambour VOR (being the last available navaid) to Maroochy airport. That way, when you became visual, you didn't have to gin around at the LSALT!
In the example GBO gives, you could submit an IFR plan, an nominate VFR procedures for the leg out and back!
How do I remember that sh!t ?
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I don't get this "nomintate a leg VFR proceedures" thing. If you're IFR you're IFR. If you're IFR and you want to maintain flight in VMC then more power to you. Better still if you're in VMC go crazy and fly at whatever level you want below LSALT. You'll still be on full reporting but if you're in class G then its not like they can stop you. The only time I'd choose to downgrade from IFR to VFR is if I was in VMC and it would significantly reduce my workload by dropping to VFR and getting rid of full reporting. You'll no longer have SARWATCH but, again, just submit a VFR SARTIME when you downgrade.
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Good one desmo
Lucky for Forkie, I was on board the day he wanted IFR into YPJT......... he was mortified when he got ditched out of the system and had to VFR it to the reporting point!
I had the trusty VTC out............. and I think he actually enjoyed it after that! Red Bull things, training RFDS........lost count of the number in the circuits at the time!
J
Lucky for Forkie, I was on board the day he wanted IFR into YPJT......... he was mortified when he got ditched out of the system and had to VFR it to the reporting point!
I had the trusty VTC out............. and I think he actually enjoyed it after that! Red Bull things, training RFDS........lost count of the number in the circuits at the time!
J
