CAP GEN question!!! please help

[k91]

I am just starting to get into the CAP GEN and I have a question to a part I can not understand

Page 22 and Page 24 both have charts

Both are in the Approach Ban Section, under titles MIN VISIBILITY AEROPLANES

One chart is for Non Precision APV or CAT 1 the other is for OPS SPEC Non Precision AVP or CAT 1

I get what a op spec is but how do the numbers in the two columns relate? Is on the numbers on the approach plate and the other column the vis you need? How would a pilot remember all these numbers?
How are these charts used by companies? Is CAP ADVISORY VIS the numbers on the approach plate?? How does it relate to the other column of VIS REPORT?

I am having a bit of a hard time with the entire thing, as it is almost written in another language to me

Thank you all (even the smart ass answers! LOL)

PS: Im a Long time float guy with a opportunity to do some IFR trg, but not handy anyone that can explain this too me

[oldtimer]

Many operators have an Ops Spec allowing lower limits than published in the CAPs. In that case, they all have the RCAPs. The restricted CAPs. Operators are able to go to a web site and then download and print off their own charts. Kelowna had a CAP minimum of 650 feet but the RCAP took you down to 250 feet. I cannot remember the vis requirement.

[AOW]

First you must determine whether your company has the ops spec. This is pretty easy by checking your COM. If the answer is yes, then the question is can you take advantage of it. There are various restrictions, and they are different if it is a precision or non-precision approach.

Now you know which chart is limiting. So you find the approach that you're planning to fly, and look next to the MDA/DH that is applicable to you, and you will see a distance in miles. This is the advisory visibility, or what the designers of the approach think is an ideal distance back from the MAP to commence the descent from MDA. The approach ban kicks in if the visibility is considerably worse than this value. Once you know which chart to use, and the advisory vis, pull out the appropriate chart, and you can determine the minimum visibility that will let you attempt the approach. I keep the CAP GEN handy in the cockpit for this reason (and for cold weather correction)!

If you wonder where the numbers come from, the non-ops spec numbers correspond to 3/4 of the advisory visibility, while the ops spec numbers are half of the advisory vis.

Good luck!

[k91]

Thanks guys this is slowly becoming more clear

So those charts are only for Commercial Operators, ok that makes sense

Would i be correct if I said:

The first chart is for those without ops spec
The second chart is for those with ops spec

For a commercial operator:
If the reported vis is 1/4 sm or 1200 RVR but the numbers on the plate by that approach (advisory vis) are 1/2 sm and RVR 2600 either

DONT HAVE OPS SPEC = NO APPROACH PAST THE FAF AND GO AROUND
or
DO HAVE OPS SPEC TO APPROACH TO 1/4 rvr 1200 AND CAN CONTINUE PAST THE FAF

[k91]

Wait ok

I think I have this

If the CAP gives a number advisory vis of 1/2sm or RVR 2600 I can go past the faf with what ever is listed in the next column

I use the first chart if I work at a place with no op spec and the second chart if I have a op spec number 19, 303, 503


Why do they bother to put an "Advisory Vis" at all? Why not just have the VIS REPORT numbers listed for the first chart and only have the ops spec chart in the cap gen


Thank you all for following my gong show this far!

[BTD]

If you are a commercial operator:

No ops spec, use the chart that corresponds to the 3/4 recommended vis

Ops spec , use the chart that corresponds to 1/2 the recommended vis.

If you are doing this at an actual commercial op read the ops spec closely. Often even with the allowance to go to 1/2 the recommended vis, for an ils there will be a restriction to 1600 rvr or other. There are additional requirements to go down to 1200 that need to be taken into account.

So your above example may not be correct, depending on on airport lighting and aircraft equipment.

After all that then you can start to factor in aerodrome operating vis.

Btd

[ahramin]

Very simple. You look up your advisory vis on the approach plate for the approach you want to do. Then you find this value in the CAP Advisory Vis column of the appropriate chart in the CAP GEN (ops spec or non). Then look at the required vis (to the right) corresponding to the Advisory Vis and voila, that's the vis you need.

[BTD]

The advisory vis is the visibility that you can expect a successful approach while maintaining a reasonable descent profile. You could always see it much closer but then would need to do a chop and drop.

In this US at "advisory vis" is limiting for the approach

[AOW]

Ok: for an ILS with 1/2 SM advisory vis...
If you are not a commercial opperator, the only approach ban that applies is below 1200 RVR. So in this case you can do the approach.

For a commercial opperator without the ops spec, the chart shows 3/8 SM OR 1600 RVR is your minimum for the approach, so at 1200 RVR, you are approach banned.

For a commercial opperator WITH the ops spec you must determine if the aircraft and airport meet the requirements for taking advantage of the ops spec: for a precision approach, you must have 2 crew, an autopilot that can shoot the coupled approach to mins, or a flight director - if you use a pilot monitored approach procedure, and the airport must have centre line lighting. If you don't meet all of those requirements, you must "fall back" to the non-ops spec numbers, and will be approach banned if the RVR is below 1600.
If all of the conditions are met (including having the ops spec), you can still shoot the approach at 1200 RVR, but will be banned if it drops further.

[wallypilot]

I think I see where you are getting confused.

CAP advisory vis is the minimum on the approach plate. This number corresponds to the minimum you require to land from that approach. However, more often than not, visibility varies over the area of the aerodrome, and the Tower reported VIS may not accurately reflect the vis at the decision point, or visibility is up and down, but tower reported VIS is not re issued to reflect that. So many variables even if tower reported vis for example 1/2SM. Basically, point is reported VIS may not accurately reflect VIS at the decision point.

So, there is the approach ban rule. This rule allows an IFR aircraft to shoot the approach when vis is as low as 75% of CAP advisory value. This serves two purposes. It allows aircraft to fly the approach when tower vis may not reflect decision point vis, or also to allow the aircraft to do the approach, and maybe take advantage of a fluctuating improvement in vis. As long as reported vis or RVR corresponds to 75% of the CAP advisory value, you can shoot the approach past the FAF. If upon reaching the decision point, you have the required Runway References,you can legally land.

Second, it prevents aircraft from doing what TC considers is a risky operation by shooting the approach when visibility is so low that in TC's opinion the likelihood of a successful landing is minimal. So TC feels that below 75% of CAP, it is not worth the risk for the aircraft to continue and "have a look". In this case you are "banned" from shooting the approach when vis is below 75% of CAP advisory value.

That is unless you are a POC operator, or as a commercial operator, you do some paperwork, and get an Ops Spec which would allow your company to magically be blessed to change that 75% value to 50%.

Make sense?

[x-wind]

Hello,

First I want to correct the first two responses.

1) The OPS SPEC 019, 303 or 503 are for the commercial operator to use the chart on page 24. That's pretty straight forward or should be. It has nothing to do with the RCAP which is OPS SPEC 099.

2) Advisory visibility has nothing to do with when approach designers think you should commence decent to the minimum decent altitude (MDA). Advisory visibility has a lot of functions as it relates to the approach ban and alternate airports, however, primarily it is published to give a minimum visibility for which the approach can be accomplished successfully. These graphs you're looking at are also for CAT 1 precision approaches, which don't have MDA's they have decision height (DH).

K91's questions:
1) The two pages you're confused about relate in the sense that they're both for commercial operators. One is for commercial operators that have OPS SPEC 019, 303 or 503 though. That is it, as the titles suggest.
2) Yes, you need to review what the approach ban is before getting into the specifics of how it works. But, you do take you're advisory visibility (look near the back of the CAP gen in the legend for what that is & compare it to the approach ban as it applies to you. If you're flight training you're going to using the general aviation approach ban chart, not the commercial operator ones)
3) Personally I don't remember the approach ban numbers, you don't need to for the written IFR test either. IFR flying requires really good cockpit organization- you will have to be able to find the information you need when you need it.
4) Companies pilots will use these charts as they are. The CAP GEN is required to be onboard the airplane. Before commencing an approach a company pilot must insure they are legally permitted to do so.
5) Visibility report is just that. The visibility reported from the aerodrome you'd like to land at.

Instrument flight rules initial training is a lot of work to understand it correctly. I started by basically reading the RAC section of the AIM. From there I went into the CAP GEN & then I started practicing flight planning exercises and working my way through the questions that came up there. I used the internet to referance things quickly along the way- a good example is google "TC.GC.CA OPS SPEC 099" the first search response is exactly what you want & in 3 minutes I know exactly what that OPS spec really is. I use to instruct IFR training at Perimeter, I worked with a few high time float pilots who were entering the IFR world - they all had the wrong initial impression that it would not be as much work as it actually was. Cheers,

[AOW]

2) Advisory visibility has nothing to do with when approach designers think you should commence decent to the minimum decent altitude (MDA). Advisory visibility has a lot of functions as it relates to the approach ban and alternate airports, however, primarily it is published to give a minimum visibility for which the approach can be accomplished successfully. These graphs you're looking at are also for CAT 1 precision approaches, which don't have MDA's they have decision height (DH).

Funny, I always assumed that the advisory vis (for a straight in approach) was the distance corresponding to where you would be on a 3 degree glideslope at MDA, or in the case of a precision approach, the distance corresponding to how far back you will be at DH, if you're on the glidepath. If not, it works out surprisingly close.

[k91]

Wow thanks so much everyone

So does a POC operator under CARS 604 need to follow this or do they go by GENERAL AVIATION APPROACH BAN?

Thanks again everyone for the answers, this is a big big help

[ahramin]

604 is not a commercial operation, so only part VI approach ban applies.

[k91]

so Private operators have to follow CAR part 602.129

Would a 702 operator fall under APP BAN for Commercial Operator or no, b/c they only do Aerial work? Unless they have IFR ops on their OC?

Thanks!

[Ki-ll]

2) Advisory visibility has nothing to do with when approach designers think you should commence decent to the minimum decent altitude (MDA). Advisory visibility has a lot of functions as it relates to the approach ban and alternate airports, however, primarily it is published to give a minimum visibility for which the approach can be accomplished successfully. These graphs you're looking at are also for CAT 1 precision approaches, which don't have MDA's they have decision height (DH).

Funny, I always assumed that the advisory vis (for a straight in approach) was the distance corresponding to where you would be on a 3 degree glideslope at MDA, or in the case of a precision approach, the distance corresponding to how far back you will be at DH, if you're on the glidepath. If not, it works out surprisingly close.

The specific wording they use is

The minimum standard visibility required for the pilot to establish visual reference in time to descend safely from the MDA is dependent upon the HAT/HAA

and for precision approaches:

The minimum standard visibility required for the pilot to establish reference in time to descent safely from the DA is dependent upon the HAT.

Then they publish several tables which describe what the minimum visibility can be and also what the credit for lights can be. This visibility cannot be lower the absolute minimum that they prescribe in another table.
I guess what they mean by "safely" is described by the maximum descent gradients on final which can be no higher than 400ft/nm (3.77 degrees), the optimum is 318ft/nm (3 degrees).

[x-wind]

There is nice to know information and there is need to know information.

From the Aeronautical Information Manual (AIM). This manual is for pilots. RAC 9.19.3 Landing Minima:
"...Published landing visibilities associated with all instrument approach procedures are advisory only. Their values are indicative of visibilities which, if prevailing at the time of approach, should result in required visual reference being established. (See GEN 5.1 for the definition.) They are not limiting and are intended to be used by pilots only to judge the probability of a successful landing when compared against available visibility reports at the aerodrome to which an instrument approach is being carried out." Published landing visibilities are also put on circling approaches.

K91, yes anyone who operates under PART VI (General Operating & Flight Rules) of the CARs is subject to 602.129 (the table in the approach ban section of the CAP GEN appropriately labelled is a more practical way for you to think about it).
Any Commercial Air Service is subject to the approach ban that is for commercial operators when they're flying IFR.

Here are some useful tips regarding the CARs.
The first number = PART
The second number = zero (REGULATION) or two (STANDARD)
The third number = Subpart

example: 603.04

This is PART VI (General Operating & Flight Rules)
It is a regulation because the second number is a zero. If it was a two it would than be a standard, but it is not.
It's Subpart 3 (Special Flight Operations)

[willow burner]

Once you have a handle on which chart you re supposed to be using, its pretty easy to remember the limiting numbers for the apprchs that you use the most.

Be sure to read the bit in the cap gen about when an apprch ban is in effect, particulary of you fly north of 60.

Also, futher to the point about MDA vs advisory vis vs a reasonable final aprrch slope, there are lots of non precision aproaches, at least up north, where breaking out at the MDA, configured to land, and at the advisory vis distance from the runway puts you in a position where a straight in apprch would be very steep, if not impossible. They are intended as circling aproaches, the option to land straight in is available if you break out early.

[ahramin]

Any examples willow burner?

[Ki-ll]

I think Chibougamau NDB A approach a good example of an approach where only circling minima are authorized due to higher than maximum gradient of descent from the FAF to MDA.

[The5chord]

Once you have a handle on which chart you re supposed to be using, its pretty easy to remember the limiting numbers for the apprchs that you use the most.

Be sure to read the bit in the cap gen about when an apprch ban is in effect, particulary of you fly north of 60.

Also, futher to the point about MDA vs advisory vis vs a reasonable final aprrch slope, there are lots of non precision aproaches, at least up north, where breaking out at the MDA, configured to land, and at the advisory vis distance from the runway puts you in a position where a straight in apprch would be very steep, if not impossible. They are intended as circling aproaches, the option to land straight in is available if you break out early.

North of 60 it doesn't apply. I believe it should be done away with completely. Why is it okay north of 60 but not south. Why is it I can get into many places special vfr or vfr with 1sm but not ifr because the approach ban is in effect at 1 1/4 or higher? Does TC prefer me to fly reduced vfr into these airports?