LPV Approaches/ Approach Lights?

airdale

airdale

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airdale
From my amateurish attempts to understand TERPS Order 8260 it does not appear that approach lighting systems are explicitly required for ILS or LPV approaches, but that rather their presence allows minimums to be reduced.

Does anyone know if it is possible to have an LPV with a 200 or 300 AGL DH and 1/2 mile viz if there is no approach light system? Have you seen any?

Said another way, can a small city airport with no space to add approach lighting ever expect to get an LPV approach to 200 or 300 AGL?
 
If they don't have room for approach lighting it's unclear they have enough clearway to get the lowest minimums anyhow.
 
250 HAT, yes, it's possible. 200 HAT? No -- that requires an approach light system. Wally or John can probably quote chapter and verse from TERPS on that.
 
flyingron said:
If they don't have room for approach lighting it's unclear they have enough clearway to get the lowest minimums anyhow.
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There are reasons other than lack of space in which to put an approach light system for there to not be one.
 
flyingron said:
If they don't have room for approach lighting it's unclear they have enough clearway to get the lowest minimums anyhow.
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Ron Levy said:
There are reasons other than lack of space in which to put an approach light system for there to not be one.
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Case in point...

Holley Mountain Airpark was all set to put in approach lights. Unfortunately, the runway sits on top of a mountain and the terrain drops off sharply beyond the runway ends. There is no way, without considerable expense, to put lights on either end.
 
Anymouse said:
Case in point...

Holley Mountain Airpark was all set to put in approach lights. Unfortunately, the runway sits on top of a mountain and the terrain drops off sharply beyond the runway ends. There is no way, without considerable expense, to put lights on either end.
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Funding is often a reason for no lights. Another reason is that if there are objects penetrating the approach surfaces enough, the mins won't drop even if there are lights, so why bother? Without a proper obstruction survey and threshold siting study, it's all just speculation.

I'd be happy to commission the survey and analysis for you. It would take something like $50K to $150K to cover it.
 
airdale said:
From my amateurish attempts to understand TERPS Order 8260 it does not appear that approach lighting systems are explicitly required for ILS or LPV approaches, but that rather their presence allows minimums to be reduced.

Does anyone know if it is possible to have an LPV with a 200 or 300 AGL DH and 1/2 mile viz if there is no approach light system? Have you seen any?

Said another way, can a small city airport with no space to add approach lighting ever expect to get an LPV approach to 200 or 300 AGL?
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Lots of factors at play with LPV. Without ALS you won't see less than 3/4, but you could see a DA of 200 if all factors are satisfied. Many GA airports have the vertical survey that permits LPV, but lack sufficient clearance in the visual segment, or perhaps there is no parallel taxiway. Without the taxiway the visibility cannot be less than 1 mile.

If the airport meets all requirements for 200 and 3/4, be happy. Approach lights simply are not worth the price at a small airport to gain 1/4 mile visibility.
 
Ken Ibold said:
Funding is often a reason for no lights. Another reason is that if there are objects penetrating the approach surfaces enough, the mins won't drop even if there are lights, so why bother? Without a proper obstruction survey and threshold siting study, it's all just speculation.

I'd be happy to commission the survey and analysis for you. It would take something like $50K to $150K to cover it.
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That's quite a price range.
 
Ken Ibold said:
Funding is often a reason for no lights. Another reason is that if there are objects penetrating the approach surfaces enough, the mins won't drop even if there are lights, so why bother? Without a proper obstruction survey and threshold siting study, it's all just speculation.

I'd be happy to commission the survey and analysis for you. It would take something like $50K to $150K to cover it.
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Trust me, obstructions on the approach path are not an issue there. Tree tops are below the threshold.
 
aterpster said:
That's quite a price range.
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Yep. It depends on a lot of stuff, including most recent available survey data and whether it was flown to the new standards. How many runway ends. Precision vs non-precision. Number, locations and extent of surface penetrations. How much the aerial survey costs. Whether there are existing PACS/SACS or whether they have to be set...
 
We have less than 300' (can't remember ,225 0r 275) and a mile with no approach lights. We had ODALS on our AIP Capital Improvement Plan but as that year neared, it turned out that the Feds would fund them only if they would result in an improvement in minimums. There were other requierments that we couldn't meet. The required Runway Prot. Zone size grew beyond what was available above ground and we would have had to buy a lot more avigation easements.
 
There were other requierments that we couldn't meet. The required Runway Prot. Zone size grew beyond what was available above ground and we would have had to buy a lot more avigation easements.
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Too bad, Graueradler, that many airport commissions that CAN hit all the targets with their airport often take it for granted and don't protect the airspace. Low minimums are very important for the areas served by the airport, but many of the "locals" don't understand just how important GA access to the area is and let things slip away. Very sad.
 
Ron Levy said:
250 HAT, yes, it's possible. 200 HAT? No -- that requires an approach light system. Wally or John can probably quote chapter and verse from TERPS on that.
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Not true. You can get 200 DH with an LPV without approach lights. The visibility requirements will be 3/4, the same as if there was an approach light system but it was inoperative. One example RNAV (GPS) RWY 6 KLKR. Note also they don't have precision markings on the runway.

http://155.178.201.160/d-tpp/1310/05853R6.PDF
 
Anymouse said:
Case in point...

Holley Mountain Airpark was all set to put in approach lights. Unfortunately, the runway sits on top of a mountain and the terrain drops off sharply beyond the runway ends. There is no way, without considerable expense, to put lights on either end.
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Ever been to MGW? The approach lights are on towers to get them up to the level of the runway.
 
aterpster said:
Lots of factors at play with LPV. Without ALS you won't see less than 3/4, but you could see a DA of 200 if all factors are satisfied. Many GA airports have the vertical survey that permits LPV, but lack sufficient clearance in the visual segment, or perhaps there is no parallel taxiway. Without the taxiway the visibility cannot be less than 1 mile.
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What's the reasoning behind the parallel taxiway requirement? Need enough viz to be able to see somebody back-taxiing in time to go around?
 
flyingron said:
Ever been to MGW? The approach lights are on towers to get them up to the level of the runway.
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Yep! That's the "Considerable expense" part. Our little airpark didn't think it was worth it. (No idea what the full cost would have been to engineer and build the towers. It was before my time there.)
 
airdale said:
Said another way, can a small city airport with no space to add approach lighting ever expect to get an LPV approach to 200 or 300 AGL?
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Yes, with an ODALS instead of ALS. Visibility minimums will be 3/4 sm (RVR 4000') and they won't even need the extra paint for precision markings AFAIK.

Ref: Table 3-2 & 3-5a, Order 8260.3.

dtuuri
 
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dtuuri said:
Yes, with an ODALS instead of ALS. Visibility minimums will be 3/4 sm (RVR 4000') and they won't even need the extra paint for precision markings AFAIK.

dtuuri
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I doubt anyone will spend the money for RVR equipment at these small airports. That means installing HIRLs as well, which is big bucks.

If everything is up to snuff you will have 3/4 without ALS or HIRLs.

If the runway is 200 and 3/4, such as KGGW Rwy 30, a Part 91-only pilot has all he/she needs.
 
Graueradler said:
We have less than 300' (can't remember ,225 0r 275) and a mile with no approach lights. We had ODALS on our AIP Capital Improvement Plan but as that year neared, it turned out that the Feds would fund them only if they would result in an improvement in minimums. There were other requierments that we couldn't meet. The required Runway Prot. Zone size grew beyond what was available above ground and we would have had to buy a lot more avigation easements.
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We are adding REILs next year. It won't change the minimums but will improve the pilot's chance of seeing the runway environment at mins.
 
(OP here) Thanks for the info, guys. Very informative.
 
aterpster said:
I doubt anyone will spend the money for RVR equipment at these small airports. That means installing HIRLs as well, which is big bucks.
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Good point. I didn't mean to imply RVR was feasible, only mentioned it as a point of reference.

aterpster said:
Your point?
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He probably wanted to indicate that REILS doesn't need more real estate, like ODALS does. Even with just REILS, 200' minimums and 3/4 sm visibility are possible according to Table 3-5a. I can say from experience that REILS isn't a lot of help at minimums on an ILS-type approach. A RAIL is much better, ODALS is a poor second. REILS is suited for circling or locating a parallel runway next to a lit-up full-blown ALS system, see my tutorial here:

dtuuri
 
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dtuuri said:
He probably wanted to indicate that REILS doesn't need more real estate, like ODALS does. Even with just REILS, 200' minimums and 3/4 sm visibility are possible according to Table 3-5a. I can say from experience that REILS isn't a lot of help at minimums on an ILS-type approach. A RAIL is much better, ODALS is a poor second. REILS is suited for circling or locating a parallel runway next to a lit-up full-blown ALS system, see my tutorial here:
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Where do you see the reference to REILs in 3-5A? 200 and 3/4 is authorized with NALS, provided everything else is in place.

ODALs came about historically as an aid for circle to land. That concept didn't go very far.
 
aterpster said:
Where do you see the reference to REILs in 3-5A? 200 and 3/4 is authorized with NALS, provided everything else is in place.
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I didn't say REILS was in the table, just that "according to" the table 200 & 3/4 is possible. NALS means "no ALS", ergo REILS is not an ALS--read under that (NALS) column.

dtuuri
 
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dtuuri said:
I didn't say REILS was in the table, just that "according to" the table 200 & 3/4 is possible. NALS means "no ALS", ergo REILS is not an ALS--read under that (NALS) column.

dtuuri
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So, what is your point about REILs?

You've lost me. :)
 
aterpster said:
So, what is your point about REILs?

You've lost me. :)
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Well, ateamer didn't respond to your question re: what ateamer's point was, so I speculated REILS was mentioned because it needs less real estate than ODALS, which I had previously mentioned. I pointed out REILS can offer the same minimums as ODALS, i.e., 200 & 3/4 which is even lower than the example ateamer gave. I cited the source for that was Table 3-5a. When pressed by you, I explained that REILS is not an ALS, so we refer to the NALS column. Capish? :)

dtuuri
 
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