JFK Lead-in lights, visual or Instrument??

[lowpitchstop]

Had a question on when you're legal to leave the MDA on the VOR 13L into JFK. Once you're at DMHYL the chart says to take over "visually" by using the Lead-in lights... I interpret that to mean passing your MAP (DMHYL) if you have the lead-in lights insight, you're legal to start down (even if you don't have the runway or runway environment etc).

Anyone have an "official" answer.

Thanks

MO

 

[Amish RakeFight]

Well, the lead-in lights are there to help guide you to the runway visually when departing the 041 radial off Canarsie. Think of the lead-in lights as a "bending" of the radial to line you up with 13L or 13R. It's really just an extension of the radial. There isn't any legal provision allowing you to descend below MDA (800') based upon acquiring the lead-in lights alone, especially if you don't have the runway in sight. The FAR's governing the descent below MDA will still be applicable. Things like charted visibility (2 miles), ability to descend using normal rates and the 10 or so visual indicators normally required. If the lead-in lights are not visually acquired by DMYHL, then you go missed. If you acquire them and lose them at some point while tracking them towards the east, you go missed. But as far as following them to the runway, you should remain at MDA while tracking the lead-in until you have the runway environment in sight.

 

[Princedietrich]

Yeah, what he said.


But in a literal answer to your original question, the leadin lights are a visual component of an instrument procedure. Rather similar to an LDA PRM approach.

 

[lowpitchstop]

I guess my big issue is.. now that you're PAST the MAP (DMYHL) MDA "should" no longer apply and the instrument portion of the approach is over ,(since you're now navigating "visually"). As per the reg, the Missed approach procedure is no longer valid IF you continue BEYOND the MAP. Now if you are at 800' (the MDA) and have the lead in lights in sight you're authorized to continue. Once PAST the MAP logic would say you're now on a Visual approach and can initiate a descent (since you may not be able to make out the runway "environment" until you roll out on final (and will be WAY too high to make a safe landing) to intercept a normal glidepath. The runway is over 35 degrees off your heading throughout most of your maneuvering.

Any thoughts.

Thanks in advance

MO

 

[727C47]

usually the vis is at least 5 miles when the Canarsie approach is in use, I have never seen it offered anywhere near minimums.at 5 miles ,even in haze you will have the LDINS and the rwy at DMYHL

 

[Amish RakeFight]

I guess my big issue is.. now that you're PAST the MAP (DMYHL) MDA "should" no longer apply and the instrument portion of the approach is over ,(since you're now navigating "visually").

MDA altitude still applies even beyond DMYHL. You may only commence descent once the required visual indicators are identified. This may take place at or before DMYHL, but it may also take place beyond DMYHL. As I stated before, coming off the 041 out of Carnarsie, you would begin to follow the lead-in lights until the runway environment is in sight. The lead-in lights serve the same purpose as the electronic radial. The lead-ins are sort of like a "bending" of the radial to follow. An extension of the 041 which helps guide you to the runway via a transition from the navigational signal to a visual signal. Even though you are navigating visually, this in and of itself does not permit a descent out of MDA if the field is not in sight. Would you begin descend out of MDA prior to reaching your calculated VDP even if the field were in sight? Probably not. Similar thing here.

As per the reg, the Missed approach procedure is no longer valid IF you continue BEYOND the MAP. Now if you are at 800' (the MDA) and have the lead in lights in sight you're authorized to continue. Once PAST the MAP logic would say you're now on a Visual approach and can initiate a descent (since you may not be able to make out the runway "environment" until you roll out on final (and will be WAY too high to make a safe landing) to intercept a normal glidepath. The runway is over 35 degrees off your heading throughout most of your maneuvering.

Actually, if you read the plate the MAP instructs are as follows:

"At or beyond MAP, climbing right turn to 4000 via heading 100 degrees and V-16 to DPK VOR/DME and hold."

So as you can see, the missed approach CAN take place either before (climb only), at or after DMYHL. You may continue via the lead-in lights without the runway environment yet in sight. IF you have the lead-in lights at DMYHL, you continue. If you lose the lead-in lights during the visual transition you go missed. You can go missed if you never acquire the lead-ins, if you acquire them and subsequently lose them, or if you follow them but pick up the runway too late to descend at a normal rate.

That you are going "visual" only means you are visually tracking the lead-ins, it is not a "visual approach" as defined in the AIM. This would be accomplished under a different set of criteria. And for one, it would require at least basic VFR - 1,000 and 3. As you can see on the approach plate for the VOR 13L, the MDA and weather is 800-2. Obviously far below any visual approach minimums.
Also, the lead-in lights help to assist in mantianing compliance with noise abatement procedures, so even when one does acquire the runway environment while following the lead-ins, you must still track the lights in order to remain clear of noise sensative areas.

As far as the runway being 35 degrees off to the right, that is not necessarily a constricting angle. You should be able to acquire the runway environment before rolling out on final. Once you have it in sight, then you may begin descent out of MDA.

 

[lowpitchstop]

Thanks "Amish Rakefight" (love that). The approach plate I'm flying off of does not use that verbage for the Missed approach.. mine reads.. RT HDG 100 intercept V16 to DPK climb 4000.

In addition, on the profile view, it shows a descent (slanted line) beginning right at DMYHL (to the runway).

I will take your advice and remain at MDA until I see the appropriate visual cues; and will go missed if too high when I see them (probably won't happen in the "real" world, but those Sim instructors love to keep the weather at Mins for the approach).

Thanks for the follow-up

MO

 

[Amish RakeFight]

FYI - the chart I referenced was an NOS chart. It includes the pictorial and written version of the MAP. The written version states AT OR BEYOND, but the pictorial symbols leave this out, providing only arrows, headings and a navaid.

It too displays the descent slant coming out of DMYHL, although this is only meant to represent the possible commencement of descent if the runway enviorment is in sight at DMYHL. The slant in and of itself does not indicate a necessity to begin an immediate descent out of MDA. It is there basically for illustrative purposes of how the approach should normally conclude. Most other charts will display a path climbing away after arrival at the MAP, since this is a "unique" approach (VOR 13L) the designers have included the dashed line to indicate the climb away portion of the MAP (as usual) but have also included a dashed bold line to indicate the ability to continue the approach beyond the charted MAP. Normally one goes missed at the charted MAP point, but here the MAP is DMYHL which is also the point where you transition to a visual path, tracking the lead-in lights. So the chart is essentially telling us that if the lead-in lights aren't acquired by DMYHL, we go missed. If the lead-in lights are acquired, we may continue to track it until the runway becomes visible. We are allowed to follow this lighted path to the respective runway (13L or 13R) at MDA.

The plate lists the ground track DME off DMYHL to 13L as 3.6 and 3.2 miles for 13R. If cleared for 13L, by the time you arrive at DMHYL, depending on visibility of course, you should be able to see the runway at this point. The 3.6 mile figure is the total groundtrack length - not the straight line distance from DMHYL direct to the threshold of 13L.

 

[59PA]

It appears on Jepp chart that LDIN lights are part of the approach light system. Therefore you may leave MDA as necessary to complete the landing, not below 100 feet without futher visual reference.

 

[Amish RakeFight]

It appears on Jepp chart that LDIN lights are part of the approach light system. Therefore you may leave MDA as necessary to complete the landing, not below 100 feet without futher visual reference.

LDIN lights are considered separate and distinguished from ALS lights which allow the descent to 100' above TDZE without any other visual cues. It states that the LDIN lights are designed to provide a track up to the ALS where once acquired, one could then descend down to 100' above the TDZE if the runway environment is not yet insight. The description goes on to state that the LDIN lights purpose is to also allow a trackable ground path flown visually to a point or distance from the runway where charted visibilities would allow the descent given the visibilities.

So in sum, after arriving at DMYHL, one must remain on the LDIN light ground track and hold MDA until the ALS or runway environment is acquired. the LDIN lights are not considered part of the ALS lighting system and thus do not permit descent below MDA without the aforementioned requirements.



http://www.naco.faa.gov/content/naco/acfstatus/RDs/04-01-162_Use_of_Lead_In_Light_Systems_LDIN.pdf

GOVERNMENT/INDUSTRY AERONAUTICAL CHARTING FORUM 04-01
April 28-April 29, 2004
Recommendation Document ​

Subject: Use of Lead-In Light Systems (LDIN)
Background/Discussion: [FONT=Arial,Arial]LDIN consists of a series or group of 3 flashing lights in a linear or cluster configuration and may be augmented by steady-burning lights. These lights are installed along the approach path at or near ground level where special problems exist such as hazardous terrain, obstructions, or noise abatement procedures. LDIN are terminated at any approved approach lighting system or at a distance from the threshold compatible with authorized visibility minimums permitting visual reference to the runway environment. An operator requested standard CAT I minima for the installation of LDIN. Order 6850.2A, Visual Guidance Lighting Systems and Order 8260.3, TERPS, denote LDIN as a VFR lighting system and not approved for use with precision or non-precision approaches. LDIN would not qualify for lighting credit under 14 CFR Part 91.175(c)(3)(i) and 121.65 1(c)(3)(i).[/FONT]