Why does this approach have higher LNAV/VNAV minimums than just LNAV?

[Rockie]

LPV's provide ILS like precision, many with 200 and a half limits, and can be produced for almost any airport anywhere without the need for an expensive ILS installation - cost savings airlines could insist on to reduce their fees paid to NavCanada, airports and other national service providers. The FAA is all over that. On Canada's east coast alone an LPV approach would often make the difference in getting in or not especially in the winter. Runway 25 in Ottawa anyone?

The safety enhancements are obvious as the weather degrades and when taken in context with stabilized approaches. They are unaffected by temperature and guarantee that the aircraft is tracking horizontally and vertically toward the correct touchdown spot on the runway upon reaching minimums. I'll take precision over non-precision any day.

[55+]

LPV's provide ILS like precision, many with 200 and a half limits, and can be produced for almost any airport anywhere without the need for an expensive ILS installation - cost savings airlines could insist on to reduce their fees paid to NavCanada, airports and other national service providers. The FAA is all over that. On Canada's east coast alone an LPV approach would often make the difference in getting in or not especially in the winter. Runway 25 in Ottawa anyone?

The safety enhancements are obvious as the weather degrades and when taken in context with stabilized approaches. They are unaffected by temperature and guarantee that the aircraft is tracking horizontally and vertically toward the correct touchdown spot on the runway upon reaching minimums. I'll take precision over non-precision any day.

Some clarification to the above. In order for Precision landing limits(200ft HAT), vis ½, (A)the airport itself has to be Certified in accordance to criteria in TP-312- Aerodrome Standards and Recommended Practices and (B) The landing surface aka Runway has to assessed as meeting Precision Criteria in regards to take off/approach sloped, strip widths, transitional slopes etc. If those criteria are not met the lowest landing minima approved is 250ft HAT

[photofly]

LPV's provide ILS like precision, many with 200 and a half limits, and can be produced for almost any airport anywhere without the need for an expensive ILS installation - cost savings airlines could insist on to reduce their fees paid to NavCanada, airports and other national service providers. The FAA is all over that. On Canada's east coast alone an LPV approach would often make the difference in getting in or not especially in the winter. Runway 25 in Ottawa anyone?

The safety enhancements are obvious as the weather degrades and when taken in context with stabilized approaches. They are unaffected by temperature and guarantee that the aircraft is tracking horizontally and vertically toward the correct touchdown spot on the runway upon reaching minimums. I'll take precision over non-precision any day.

A NavCanada manager responsible in this area told me the delays in the introduction of more LPV approaches are due to airport operators: an LPV approach needs a detailed site survey for obstacles and a commitment from the airport operator to fund the periodic re-surveys required (as they are for an ILS with similar minimums). Airport operators are not exactly falling over themselves to sign up for this new ongoing cost.

[Rockie]

A NavCanada manager responsible in this area told me the delays in the introduction of more LPV approaches are due to airport operators: an LPV approach needs a detailed site survey for obstacles and a commitment from the airport operator to fund the periodic re-surveys required (as they are for an ILS with similar minimums). Airport operators are not exactly falling over themselves to sign up for this new ongoing cost.

Airport operators can be very short sighted (look at Ottawa), and so can airlines. A LPV gives ILS like capability without the need for an expensive ILS installation. No brainer...

[photofly]

If you present it as a choice between an LPV approach and an ILS then it's a no brainer, sure. But that's a false choice. Most airports are clearly happy having neither.

It may be true that a Ford Galaxy is cheaper or better value than a Ferrari, but that's irrelevant if you don't want to buy a car at all.

[Rockie]

If you present it as a choice between an LPV approach and an ILS then it's a no brainer, sure. But that's a false choice. Most airports are clearly happy having neither.

It may be true that a Ford Galaxy is cheaper or better value than a Ferrari, but that's irrelevant if you don't want to buy a car at all.

Think of it this way, a community somewhere that relies on its airport but only has a crappy NDB approach has someone offer to install and maintain an ILS installation with 250 foot minimums to all its runways - for free. All the community has to do is get someone to build the approach for it.

Sure, the community might pass up such a deal but it would be foolish of them to do so.

Alternatively an airport has instrument runways but cannot justify the cost of purchasing and maintaining a CAT I ILS, or maybe they can but recognize there is a much cheaper option that provides the same capability.

Trying to find an argument here against LPV's but I just can't.

[photofly]

An LPV approach is not free! They have to pay for annual surveys! For ever! Expensive ongoing costs to maintain the approach! Costs money! Every year! Not free! Cheaper than an ILS, but not free!

[Rockie]

An LPV approach is not free! They have to pay for annual surveys! For ever! Expensive! Cheaper than an ILS, but not free!

Yes it's free, the Americans are paying for it. And if the airport already has a crappy NDB approach they're already paying for surveys. Crappy NDB/VOR approach with a navaid that needs to be installed and maintained - or a precision LPV approach that doesn't? Hmmm, let's think about that for a second...,

[photofly]

What are you talking about? The Americans are going to pay for surveyors in fluorescent jackets with theodolites to troll out to Quaqtaq every year to confirm there are no new encroachments on the approach so that Administration Régionale Kativik can have an LPV approach at their airport? You're smoking some good stuff there!

The ongoing survey requirements for a precision or precision-like approach are much higher than anything required for an NDB or LNAV non-precision approach. Airports have been slow to sign up for those significant additional costs.

[Rockie]

What are you talking about? The Americans are going to pay for surveyors in fluorescent jackets with theodolites to troll out to Quaqtaq every year to confirm there are no new encroachments on the approach so that Administration Régionale Kativik can have an LPV approach at their airport? You're smoking some good stuff there!

The Americans are paying 100% of the cost of the GPS and SBAS systems, and have guaranteed full time, no cost availability to all users. Look it up. The Europeans and Russians have done the same.

If the Administration Regionale Kativik is already paying to survey a crappy NDB approach doesn't a LPV make more sense? In fact they can have both since they're paying for the survey anyway right? Obstacle data is obstacle data - hills don't get higher just because there's another approach being built.

What's so hard to understand about this really?

[AuxBatOn]

Antenna and structures are built. The approach needs to be re-surveyed every year at the operator's cost.

[photofly]

What are you talking about? The Americans are going to pay for surveyors in fluorescent jackets with theodolites to troll out to Quaqtaq every year to confirm there are no new encroachments on the approach so that Administration Régionale Kativik can have an LPV approach at their airport? You're smoking some good stuff there!

The Americans are paying 100% of the cost of the GPS and SBAS systems, and have guaranteed full time, no cost availability to all users. Look it up. The Europeans and Russians have done the same.

If the Administration Regionale Kativik is already paying to survey a crappy NDB approach doesn't a LPV make more sense? In fact they can have both since they're paying for the survey anyway right? Obstacle data is obstacle data - hills don't get higher just because there's another approach being built.

What's so hard to understand about this really?

Apparently the bit that's difficult for you to understand is that as a plain fact, the ongoing survey costs of an LPV approach are much higher than the ongoing survey costs of LNAV, NDB approaches et al. And that airport operators are not rushing to commit to those extra costs.

You find it incomprehensible that airports aren't opening LPV approaches every fortnight. I give you the reason, as reported to me by the NavCanada manager responsible in Ontario for LPV approaches, that makes it entirely comprehensible. Frustrating, sure - but understandable.

[complexintentions]

We still have the option to use LNAV only minimums instead of the LNAV/VNAV minimums and frequently do if weather isn't a deciding factor as there is a lot less work required for LNAV only approaches.

Could you please explain what you mean that "there is a lot less work required for LNAV only approaches"? Perhaps in the setup phase i.e. approach validation and the like, but surely flying an approach with vertical/horizontal guidance is a lot less work than doing it in basic modes?

Incidentally I've never done a LPV approach in my entire career, I confess I had to look into the term. I gather it's more of a Canada/US thing? Other than ILS, my own airline operations have always been LNAV/VNAV. (Pre-airline, different story! Chasing that NDB needle when the wind is howling, ugh, don't miss it.) Even for a VOR approach, if it's in the database, can be flown as an overlay with LNAV/VNAV guidance. (To MDA, of course). On very rare occasion if the approach won't validate the vertical might be flown in V/S or FPA, but in thousands of approaches that's happened maybe twice.

I agree with Rockie 100% that airports over a certain size that drag their heels on lower-minimum approaches are shortsighted and saving a dime to spend a dollar. And of course there's the safety issue, but as they like to say in Canadian aviation, "Safety Third!". I mean really, what's the odd 320 plunking in short of YHZ between friends?

[Rockie]

In the US there are 1291 CAT I ILS's.

In the US as of last May there were 3678 LPV approaches, 940 of which have 200 foot minimums and 1739 of which are to non-ILS runways. More are being developed every month.

In the US there are a combined 1681 NDB/VOR approaches compared to 6073 LNAV approaches and 3553 LNAV/VNAV approaches.

The FAA clearly gets it.

Your airports, TC and too many operators in Canada might not get it yet Photofly, but sooner or later they will.

Also if you would please explain the cost difference in finding the highest obstacles in any given area. Does a 200 foot tower on final cost more to find for a LPV approach than it does for a NDB approach? Is the obstacle data not valid for both approaches? In the OP example the controlling obstacle for the LPV seems to be the same one for the circling. Did it cost more to find for the LPV?

[photofly]

I think the FAA funds the costs of the LPV approach, much like they provide a lot of airport funding, out of tax dollars.

Canada doesn't have nearly the same level of federal investment in aviation. But if we did, those dollars aren't free - they come out of everyone's pocket. Most people would probably say that the people who would benefit from better approaches should pay, so that means higher airfares and more investment from airlines into airports. I think everyone "gets it" but nobody has an economic incentive to do anything about it.

Also if you would please explain the cost difference in finding the highest obstacles in any given area. Does a 200 foot tower on final cost more to find for a LPV approach than it does for a NDB approach? Is the obstacle data not valid for both approaches? In the OP example the controlling obstacle for the LPV seems to be the same one for the circling. Did it cost more to find for the LPV?

I can't answer that. I can only tell you what was told to me, which is that more or less any airport in Canada can have an LPV approach approved shortly after pressing the button on approving the ongoing survey costs. The lack of LPV approaches is entirely down to airport operators not providing the funding.

[Rockie]

I think the FAA funds the costs of the LPV approach, much like they provide a lot of airport funding, out of tax dollars.

Canada doesn't have nearly the same level of federal investment in aviation. But if we did, those dollars aren't free - they come out of everyone's pocket. Most people would probably say that the people who would benefit from better approaches should pay, so that means higher airfares and more investment from airlines into airports. I think everyone "gets it" but nobody has an economic incentive to do anything about it.

Oh no Photofly, very few people in TC, at airports or in the airlines here in Canada "get it" yet, and you just inadvertently said why. They don't see the economic (or safety) incentive to do so.

But they will eventually.

[photofly]

I'm afraid I don't share your certainly that riches and safety nirvana await us as soon as Sleeping Beauty in the airport finance department wakes up from her slumbers and notices the LPV possibilities. I think they do the sums as carefully as they can - certainly more carefully than you and with better data than you - and act if the results show a benefit.

[valleyboy]

The problem is LPV requires WAAS which costs money. Money most (not all) airlines will not spend until they're forced to

I have not seen a GPS not WAAS enabled in the last 12 years but then again I never worked for a level 1 carrier. I can remember the day and that was about 25 years ago when were were laughing at the "big red" going vor to vor with no area nav and to us it was a no brainer that it was required equipment even back then. Now fast forward to close to present day and the "modern" fms systems with no GPS module -- DAMN!!!

[Rockie]

And I wish I could share your certainty Photofly that decision makers are as good as you seem to think. Evidence doesn't support it though. How many companies have sacrificed safety and their very future to present a good quarterly bottom line?

No, I don't share your rosy certainty at all.

[55+]

Actually an Instrument Approach Procedure(including anything with vertical guidance) can be designed to any airstrip without any type of runway assessment, however the lowest MDA/DA/DH authorized is 500ft HAT. There are many examples where this has indeed happened, I did designs to such locations and it was certainly better than nothing.

[photofly]

So LNAV and NDB approaches don't need any survey at all? If so, that would certainly be a bit cost differentiator compared to LPV.

[55+]

Correct, if a specific landing surface/runway is assessed as non-instrument(no survey) the lowest minima authorized is 500ft HAT, no matter what the procedure, even WAAS LPV. As mentioned there are good many examples in the CAP and more specific in the RCAP. If ROC + governing obstacle in the final approach segment show by calculation a HAT under 500ft on a non-instrument runway, it is a requirement to bring up the HAT to 500ft or above.

[Rockie]

Correct, if a specific landing surface/runway is assessed as non-instrument(no survey) the lowest minima authorized is 500ft HAT, no matter what the procedure, even WAAS LPV. As mentioned there are good many examples in the CAP and more specific in the RCAP. If ROC + governing obstacle in the final approach segment show by calculation a HAT under 500ft on a non-instrument runway, it is a requirement to bring up the HAT to 500ft or above.

A LPV could still be produced for the airport with 500' minimums. That would still provide precise IFR lateral and vertical guidance toward the touchdown zone that would be unaffected by temperature. Still a win as far as anybody would be concerned even with higher minimums. Lots better than no instrument approach.

And guess what? No navaid required on the ground to pay for, monitor or maintain.

What was the argument against LPV's again?

[photofly]

I don't think most people would be slightly enthused to see an LPV approach to 500' - there's not much point. In fact I can hear the bitching on AvCanada about it already.

Most new GPS boxes will give you an advisory glide slope on any non-precision approach - the benefit of an LPV is ILS-like minimums.

[Rockie]

I don't think most people would be slightly enthused to see an LPV approach to 500' - there's not much point. In fact I can hear the bitching on AvCanada about it already.

Most new GPS boxes will give you an advisory glide slope on any non-precision approach - the benefit of an LPV is ILS-like minimums.

That's hardly the only benefit. Independence from any ground navaid, and a big one for Canada is their immunity from barometric errors. And I'll bet there are lots, and lots, and lots of communities in Canada without any kind of IFR approach who would welcome one even with 500 foot minimums (not to mention pilots and operators) and many more who would love to have true LPV minimums and the accuracy they provide since the terrain already has to be surveyed. Plenty also who would gladly pay for the survey since they don't have to pay for a ground based navaid.

Come on Photofly, quit trying to invent reasons to not get one of these. They're the greatest thing to come around in ages and I'm surprised they aren't sprouting up everywhere. The only thing better as far as I'm concerned are GLS's, and I can't wait until they become the new standard everywhere.