Why are the LPV approaches going away?

timotb

timotb

Filing Flight Plan
Joined
Jul 16, 2014
Messages
18
Display Name
Display name:
Tim
Does anyone know why the FAA is replacing RNAV vertical guidance approaches with non-vertical guidance approaches? LPV -> LP Back to the old chop and drop flying.
 
timotb said:
Does anyone know why the FAA is replacing RNAV vertical guidance approaches with non-vertical guidance approaches? LPV -> LP Back to the old chop and drop flying.
Click to expand...

What do you base that statement on ?
 
I am also interested in the source for this statement or some example procedures.

There is a situation where if a new obstacle survey is performed, it can result in new obstacles (or trees growing) that would prohibit an LPV but allow an LP. So if that was the case, LPV could be removed in exchange for LP. But that would be a case-by-case basis, not a blanket policy.
 
weilke said:
What do you base that statement on ?
Click to expand...
I have been noticing LPV approaches/ vertical guidance approaches being replaced with LP approaches at smaller airports. KAKR, KTSO are just two examples. I have been under the impression that this is a trend in the last few years. My source was a pilot group gathering and personal observation.
 
Last edited:
timotb said:
I have been noticing LPV approaches/ vertical guidance approaches being replaced with LP approaches at smaller airports. KAKR, KTSO are just two examples
Click to expand...

So you pick two airports in NE Ohio and promote the FAA is doing away with LPV approaches?

See note at KTSO and KAKR in profile view, Visual Segment - Obstacles. There are minimums to keep you away from stuff and an LPV won’t do it.
 
Last edited:
Doesn’t surprise me, less value for more tax dollars.
 
Clip4 said:
So you pick two airports in NE Ohio nd promote the FAA is doing away with LPV approaches? See note at KTSO, Visual Segment - Obstacle
Click to expand...
Your right. It's a small observation. Am I to assume no one else is seeing this trend?
 
timotb said:
Your right. It's a small observation. Am I to assume no one else is seeing this trend?
Click to expand...
This “trend” to higher minimums due to added/growing obstacles has been there since long before GPS approaches came into being.
 
timotb said:
I have been noticing LPV approaches/ vertical guidance approaches being replaced with LP approaches at smaller airports. KAKR, KTSO are just two examples. I have been under the impression that this is a trend in the last few years. My source was a pilot group gathering and personal observation.
Click to expand...

I'm not sure what you mean. The RNAV approaches at KAKR and KTSO never had LPV minimums. Therefore, they were not downgraded, they just don't have the obstacle environment to support LPV in the first place. The big clue in these two cases is the presence of the "visual segment - obstacles" note.

Now, if you're talking about the advisory vertical guidance that Garmin and Jeppesen provide which would be called "LP+V" in these cases, that could be causing the confusion. Garmin/Jepp make this advisory vertical guidance available on non-vertically guided approaches as an aid. They use the published Vertical Descent Angle, normally 3.00 degrees, to do this. You will see this on the chart in the profile view as an angle sign then 3.00, above the TCH.

However, if there are substantial obstacles in the visual segment (like in these two cases), there is no VDA published and therefore no angle for Garmin/Jepp to use, so they will not create the advisory glidepath, therefore no LP+V (or LNAV+V).
 
MauleSkinner said:
This “trend” to higher minimums due to added/growing obstacles has been there since long before GPS approaches came into being.
Click to expand...

They can’t afford a chainsaw? Or need a number for a landscaper?


They’ll reduce safety vs trimming a tree, but won’t let people with ADHD fly a airplane for...safety. Oh FAA, never change lol
 
James331 said:
They can’t afford a chainsaw? Or need a number for a landscaper?

They’ll reduce safety vs trimming a tree, but won’t let people with ADHD fly a airplane for...safety. Oh FAA, never change lol
Click to expand...

Not to ruin a righteous anti-government rant, but in most of these cases it's not the FAA that needs to (or even can) take action - it's the airports, local government and communities.

For example, if the trees are growing to an unsafe height, the FAA will notify the airport. The airport might be owned by the city or county or state, or be privately owned. But it's not owned by the FAA, so the best they can do is notify the owner that there is a problem. It's up to the owner to do something about it. If the tree is on airport property, then it might be just as simple as renting a chainsaw. Or it might not, depending on local environmental considerations. If the tree is off airport property, then it becomes a matter of negotiating with the landowner to do something about it.

If the tree is not lowered or removed, then the FAA has no choice but to raise minimums or NA the procedure or a few other such options.
 
RussR said:
Not to ruin a righteous anti-government rant, but in most of these cases it's not the FAA that needs to (or even can) take action - it's the airports, local government and communities.

For example, if the trees are growing to an unsafe height, the FAA will notify the airport. The airport might be owned by the city or county or state, or be privately owned. But it's not owned by the FAA, so the best they can do is notify the owner that there is a problem. It's up to the owner to do something about it. If the tree is on airport property, then it might be just as simple as renting a chainsaw. Or it might not, depending on local environmental considerations. If the tree is off airport property, then it becomes a matter of negotiating with the landowner to do something about it.

If the tree is not lowered or removed, then the FAA has no choice but to raise minimums or NA the procedure or a few other such options.
Click to expand...

If the airport took tax dollars out of our paychecks to get that approach they need to do their part, perhaps instead of going after all the dumb crap the FAA goes after they could go after these airport owners/muni, forced them pay back that money in a insanely short period of time, or fine them XYZ amount of money a day, and have assists taken if they don’t pay up, it’s what the government does to citizens after all.

Thing is to me tax is tax and government is government
 
James331 said:
If the airport took tax dollars out of our paychecks to get that approach they need to do their part, perhaps instead of going after all the dumb crap the FAA goes after they could go after these airport owners/muni, forced them pay back that money in a insanely short period of time, or fine them XYZ amount of money a day, and have assists taken if they don’t pay up, it’s what the government does to citizens after all.

Thing is to me tax is tax and government is government
Click to expand...
Yes, Grant Assurance 16, 19, 20, and 21 obligate the airport sponsors to remove obstructions when able, or mark and illuminate them as necessary. They are also required to take necessary steps to ensure compatible land use around the airport. Problem is, not all airport authorities have the ability to compel adjacent land owners to remove obstructions. If the FAA were to penalize the airport sponsor, it would be in the form of denial future AIP funds, which would be counter productive to users of the airport.
 
Brad Z said:
Yes, Grant Assurance 16, 19, 20, and 21 obligate the airport sponsors to remove obstructions when able, or mark and illuminate them as necessary. They are also required to take necessary steps to ensure compatible land use around the airport. Problem is, not all airport authorities have the ability to compel adjacent land owners to remove obstructions. If the FAA were to penalize the airport sponsor, it would be in the form of denial future AIP funds, which would be counter productive to users of the airport.
Click to expand...

You’d think they would verify control over trees getting XYZ high would be assured before they spend the $$ on the approach
 
James331 said:
You’d think they would verify control over trees getting XYZ high would be assured before they spend the $$ on the approach
Click to expand...
Are you suggesting that they shouldn't build an approach if they can't get 200 & 1/2 minimums? The reality

it isn't realistic to require the airport to control every land parcel that could have an obstruction that penetrates the 34:1 surface area of an approach. Often times the obstructions aren't discovered until the survey has been completed (often funded by the FAA). It wouldn't make sense to spend the Mkney on a survey but not design an approach to the runway, even if the minimums are increased due to obstructions.
 
timotb said:
Your right. It's a small observation. Am I to assume no one else is seeing this trend?
Click to expand...
I'm not seeing any trend. Having said that, it's up the airport, not the FAA, to maintain the obstacle free areas for LPV. LPV is the same as Category I ILS in that sense.
 
timotb said:
Your right. It's a small observation. Am I to assume no one else is seeing this trend?
Click to expand...

I think everyone agrees the answer is no, but people are going to continue to argue about it for several more pages.
 
Brad Z said:
Are you suggesting that they shouldn't build an approach if they can't get 200 & 1/2 minimums? The reality

it isn't realistic to require the airport to control every land parcel that could have an obstruction that penetrates the 34:1 surface area of an approach. Often times the obstructions aren't discovered until the survey has been completed (often funded by the FAA). It wouldn't make sense to spend the Mkney on a survey but not design an approach to the runway, even if the minimums are increased due to obstructions.
Click to expand...

Yeah, and trees grow.

Caution: OT
Last week I was having a happy chat over a glass of wine and commented on how cool I thought some of the autopilot features are that are appearing in cars. Since we were the only 2 people at the pool side bar, I tried to engage the bartender in the conversation. His only reaction was an anti-government rant from somewhere way out in right field, “you know they’ll never let it happen when they see how much money they’ll lose”.

I’m thinking, “Huh”? Who is ‘they’ and what money will ‘they’ be losing? He went on to explain the obvious; that auto-driven cars will not get any tickets for speeding or running red lights and that there is no way the guv’ment will ever give up that revenue. Therefore ‘they’ will never allow them.

As I tried to recover from severe conversational whiplash, I tried to redirect the conversation to the technical or social aspects of auto-driven cars. But no, in his mind there was nothing else to consider. They will never allow such cars due to the loss in revenue from traffic violations. Wow

Explains a lot or at least something.


Sent from my iPad using Tapatalk Pro
 
Brad Z said:
Are you suggesting that they shouldn't build an approach if they can't get 200 & 1/2 minimums? The reality

it isn't realistic to require the airport to control every land parcel that could have an obstruction that penetrates the 34:1 surface area of an approach. Often times the obstructions aren't discovered until the survey has been completed (often funded by the FAA). It wouldn't make sense to spend the Mkney on a survey but not design an approach to the runway, even if the minimums are increased due to obstructions.
Click to expand...

Not at all, just they should be like
“Hey so those trees are not in the critical area, but probably will be in a few years, are you guys willing and able to make sure they don’t above XYZ feet tall”
 
You've never dealt with land owners adjacent to an airport. Often times those relationships are quite strained. We as the airport (aka the government) can't just go onto private property and cut down someone's tree.

Also, there has been some changes to obstruction standards over the years as well. Most recently, the obstruction clearance criteria for circling approaches. This has caused many approaches to see increased minimums as a larger margin of safety.
 
James331 said:
They can’t afford a chainsaw? Or need a number for a landscaper?
Click to expand...

It's not always that simple. The controlling obstacles may not be on airport property, and may require permission of private property owners to remediate.
 
James331 said:
Not at all, just they should be like
“Hey so those trees are not in the critical area, but probably will be in a few years, are you guys willing and able to make sure they don’t above XYZ feet tall”
Click to expand...

Did you read the Grant Assurances I cited? It already exists:

20. Hazard Removal and Mitigation. [Airport Sponsor] will take appropriate action to assure that such terminal airspace as is required to protect instrument and visual operations to the airport (including established minimum flight altitudes) will be adequately cleared and protected by removing, lowering, relocating, marking, or lighting or otherwise mitigating existing airport hazards and by preventing the establishment or creation of future airport hazards.
 
Brad Z said:
Did you read the Grant Assurances I cited? It already exists:

20. Hazard Removal and Mitigation. [Airport Sponsor] will take appropriate action to assure that such terminal airspace as is required to protect instrument and visual operations to the airport (including established minimum flight altitudes) will be adequately cleared and protected by removing, lowering, relocating, marking, or lighting or otherwise mitigating existing airport hazards and by preventing the establishment or creation of future airport hazards.
Click to expand...

So these LPVs that we paid for are going away due to a failure of the airport management to do their jobs? Wonder if that’s something someone could sick a lawyer on them for, if individuals were held personally to the fire you’d probably get less shenanigans at the expenses of the flying public.
 
RussR said:
I'm not sure what you mean. The RNAV approaches at KAKR and KTSO never had LPV minimums. Therefore, they were not downgraded, they just don't have the obstacle environment to support LPV in the first place. The big clue in these two cases is the presence of the "visual segment - obstacles" note.

Now, if you're talking about the advisory vertical guidance that Garmin and Jeppesen provide which would be called "LP+V" in these cases, that could be causing the confusion. Garmin/Jepp make this advisory vertical guidance available on non-vertically guided approaches as an aid. They use the published Vertical Descent Angle, normally 3.00 degrees, to do this. You will see this on the chart in the profile view as an angle sign then 3.00, above the TCH.

However, if there are substantial obstacles in the visual segment (like in these two cases), there is no VDA published and therefore no angle for Garmin/Jepp to use, so they will not create the advisory glidepath, therefore no LP+V (or LNAV+V).
Click to expand...


Thank you Russ. Exactly my point. LP+V approaches on the Garmin 430w seems to me to be fewer than just a few years ago. Using the LPV approaches was a bad example on my part. This is disappointing as the alternative to "advisory" non-precision rnav approaches without vertical guidance is "chop and drop". None of the airports I would point to as an example have obstacles as an issue in my opinion. Garmin is just eliminating them from the procedures data base. So Garmin, NOT the FAA is responsible for fewer advisory vertical guidance approaches; if we can agree on that?
 
Last edited:
timotb said:
Thank you Russ. Exactly my point. LP+V approaches on the Garmin 430w seems to me to be fewer than just a few years ago. Using the LPV approaches was a bad example on my part. This is disappointing as the alternative to "advisory" non-precision rnav approaches without vertical guidance is "chop and drop". None of the airports I would point to as an example have obstacles as an issue in my opinion.
Click to expand...
That’s why we have people to build approaches for us...so we don’t have to know or have an opinion as to which obstacles are an issue.
 
The removal of a VDA and noting of "visual segment - obstacles" (which then results in Garmin/Jepp removing the advisory glidepath +V) is based on the FAA's Flight Inspection evaluation of the approach. It's not just based on survey data and calculations.

The obstacle clearances used in TERPS are not based on extreme worst case scenarios, but are indeed based on "pretty bad" scenarios. So, your altimeter setting is off, your equipment isn't exactly calibrated, you're not flying perfectly, you're below glidepath, the wind is adverse, you're in the fastest airplane allowed by the categories published on the approach, all of that.

So often what looks clear to us in a 172 on a nice clear day with everything working perfectly, may not meet the stringent clearance requirements.
 
RussR said:
The removal of a VDA and noting of "visual segment - obstacles" (which then results in Garmin/Jepp removing the advisory glidepath +V) is based on the FAA's Flight Inspection evaluation of the approach. It's not just based on survey data and calculations.

The obstacle clearances used in TERPS are not based on extreme worst case scenarios, but are indeed based on "pretty bad" scenarios. So, your altimeter setting is off, your equipment isn't exactly calibrated, you're not flying perfectly, you're below glidepath, the wind is adverse, you're in the fastest airplane allowed by the categories published on the approach, all of that.

So often what looks clear to us in a 172 on a nice clear day with everything working perfectly, may not meet the stringent clearance requirements.
Click to expand...

Which is counter intuitive, +V would put you in position to intercept VASI/PAPI to avoid the visual segment obstacles.
 
timotb said:
Thank you Russ. Exactly my point. LP+V approaches on the Garmin 430w seems to me to be fewer than just a few years ago. Using the LPV approaches was a bad example on my part. This is disappointing as the alternative to "advisory" non-precision rnav approaches without vertical guidance is "chop and drop". None of the airports I would point to as an example have obstacles as an issue in my opinion. Garmin is just eliminating them from the procedures data base. So Garmin, NOT the FAA is responsible for fewer advisory vertical guidance approaches; if we can agree on that?
Click to expand...

I could see Garmin removing the +V approaches due to potential liability. The +V part of the approaches are not necessarily FAA approved or flight checked. The glidepath that Garmin generates could inadvertently cause someone to go below minimums at a step down fix, or to use the MDA as a DH/DA, which actually has different obstacle clearance criteria. I could see the company asking why are we putting something out there that isn't official and opening our company up to the risk.
 
Clip4 said:
Which is counter intuitive, +V would put you in position to intercept VASI/PAPI to avoid the visual segment obstacles.
Click to expand...
But the +V assumes IFR/TERPS obstacle clearances, which don’t exist below MDA for those runways, even if the visual requirements for the VASI/PAPI do.
 
MauleSkinner said:
But the +V assumes IFR/TERPS obstacle clearances, which don’t exist below MDA for those runways, even if the visual requirements for the VASI/PAPI do.
Click to expand...

+V is advisory to the MDA, +V is never applicable below the MDA.
 
Clip4 said:
+V is advisory to the MDA, +V is never applicable below the MDA.
Click to expand...
+V is only provided if that advisory glidepath can be flown from the FAF to the runway using TERPS criteria. In the case of the approaches in question, it can’t, therefore no advisory glidepath.
 
James331 said:
So these LPVs that we paid for are going away due to a failure of the airport management to do their jobs? Wonder if that’s something someone could sick a lawyer on them for, if individuals were held personally to the fire you’d probably get less shenanigans at the expenses of the flying public.
Click to expand...

It's more like the FAA changes their obstacle clearance requirements to improve safety and find obstacles that now penetrate protected areas where they did not before. And some of those obstacles may be far away from the airport on privately owned property. Unless private property owners consent to remediation, the approach and minimums must be altered to meet requirements. I think is it inappropriate to apply punitive measures to airport management to fail to anticipate changes in approach design margins promulgated by the FAA. As usual, boiling down complex regulatory problems into a simple black and white complaints is rarely productive. We've had several obstacle issues with our LPV approaches over the years and in each case we were able to work with the FAA to make required remediation or reach an accommodation that maintains maximal usefulness while respecting private property owner rights. Nobody has threatened to take away an LPV approach at our airport or one nearby, but some have been redesigned to meet updated safety standards.
 
chemgeek said:
It's more like the FAA changes their obstacle clearance requirements to improve safety and find obstacles that now penetrate protected areas where they did not before. And some of those obstacles may be far away from the airport on privately owned property. Unless private property owners consent to remediation, the approach and minimums must be altered to meet requirements. I think is it inappropriate to apply punitive measures to airport management to fail to anticipate changes in approach design margins promulgated by the FAA. As usual, boiling down complex regulatory problems into a simple black and white complaints is rarely productive. We've had several obstacle issues with our LPV approaches over the years and in each case we were able to work with the FAA to make required remediation or reach an accommodation that maintains maximal usefulness while respecting private property owner rights. Nobody has threatened to take away an LPV approach at our airport or one nearby, but some have been redesigned to meet updated safety standards.
Click to expand...

I can give you a perfect example here. We have one runway that has a LNAV only GPS approach. We can't get a LPV approach because of an old barn located just outside of the airport fence. The farmer that owns the barn refuses to sell, and even managed to get it listed on the National Historic Registry to prevent the airport from taking it. There is zoning in place today that would prevent anyone from building so close to the end of the runway, but this building is grandfathered because it predated the zoning ordinance. The airport's hands are tied on the issue, so why punish the airport for something totally out of their control?
 
midwestpa24 said:
I can give you a perfect example here. We have one runway that has a LNAV only GPS approach. We can't get a LPV approach because of an old barn located just outside of the airport fence. The farmer that owns the barn refuses to sell, and even managed to get it listed on the National Historic Registry to prevent the airport from taking it. There is zoning in place today that would prevent anyone from building so close to the end of the runway, but this building is grandfathered because it predated the zoning ordinance. The airport's hands are tied on the issue, so why punish the airport for something totally out of their control?
Click to expand...

Be a shame if that barn caught on fire and burned down ;-)


Tom
 
midwestpa24 said:
I could see Garmin removing the +V approaches due to potential liability. The +V part of the approaches are not necessarily FAA approved or flight checked. The glidepath that Garmin generates could inadvertently cause someone to go below minimums at a step down fix, or to use the MDA as a DH/DA, which actually has different obstacle clearance criteria. I could see the company asking why are we putting something out there that isn't official and opening our company up to the risk.
Click to expand...
It won't be coded if it violates a step-down.
 
You must log in or register to reply here.
Back
Top