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Interesting Approach Plates

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I recently came by these two articles:

 

7 Instrument Approaches You Have to See to Believe

The Approach Plate Olympics - More Crazy Charts

 

And there's really some interesting stuff in there

 

This DME arc all the way to the runway kills me!

MTN.png

 

The missed approach of Aspen has its own LOCALIZER!:

ASE.png

 

And this approach is done completely leveled to the MAP:

SUN.png

 

Do you have some others worth sharing? If so, please do! :)

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This DME arc all the way to the runway kills me!

Yes, this one is very unique, other approaches I have seen countless times.

 

If you use something like G1000 - it can normally fly approaches with an arc very easily with A/P coupled. But the catch is that and arc is flown with GPS guidance and the final approach course must be flown with whatever is prescribed - VOR, LOC, etc. But here the whole approach including the final course is an arc- I went to see how my G1000 Garmin trainer would handle it - it turns out this particular approach is missing from its database. All other approaches at MTN are available except this one, makes actually perfect sense if you realize how a typical approach within G1000 is constructed, this approach escapes typical classification.

 

Thanks for sharing.

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I flew an FSEconomy assignment in X-Plane yesterday into Castlegar CYCG (Canada), which has a fun altitude drop over the hill and then a turn to line up with the runway down in the valley. This was flying a Turbo Goose so it was easy, but it's a challenge for anything fast and heavy.

 

 

castlegar.jpg

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Yes, this one is very unique, other approaches I have seen countless times.

 

If you use something like G1000 - it can normally fly approaches with an arc very easily with A/P coupled. But the catch is that and arc is flown with GPS guidance and the final approach course must be flown with whatever is prescribed - VOR, LOC, etc. But here the whole approach including the final course is an arc- I went to see how my G1000 Garmin trainer would handle it - it turns out this particular approach is missing from its database. All other approaches at MTN are available except this one, makes actually perfect sense if you realize how a typical approach within G1000 is constructed, this approach escapes typical classification.

 

Thanks for sharing.

 

I imagine the pilot would have to manually fly the arc until crossing R-047, at which point he would see the runway and just fly in visually. The ARC all the way to touchdown is an "idealization" I believe.

 

Here's the up to date plate: https://skyvector.com/files/tpp/1603/pdf/05222VDTZ15.PDF

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I imagine the pilot would have to manually fly the arc until crossing R-047, at which point he would see the runway and just fly in visually. The ARC all the way to touchdown is an "idealization" I believe.

 

Here's the up to date plate: https://skyvector.com/files/tpp/1603/pdf/05222VDTZ15.PDF

 

You'd continue flying the 14.7 DME arc and descending to 900'. Upon crossing the BAL 060 radial at or above 900', then you'd execute the missed. The MAP is ~3.3 miles from the 047 radial (ZOVAP), and with the lowest mins requiring 1 mile, still need guidance to get closer.

 

Remember flying this years ago during my multi- training. Losing (simulated) an engine inside the FAF, and then shooting the missed onto another arc and the hold was sporty...

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You'd continue flying the 14.7 DME arc and descending to 900'. Upon crossing the BAL 060 radial at or above 900', then you'd execute the missed. The MAP is ~3.3 miles from the 047 radial (ZOVAP), and with the lowest mins requiring 1 mile, still need guidance to get closer.

 

Right, that's following the chart exactly. But if you happen to see the runway by the point you descend through 1200ft, you'd fly in visually and forget about following the arc, right?

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Right, that's following the chart exactly. But if you happen to see the runway by the point you descend through 1200ft, you'd fly in visually and forget about following the arc, right?

 

1200 ft has nothing to do with it. You can abandon an instrument approach and proceed visually at any point (assuming certain criteria are met). However, yes, on this approach, if I saw the airport and could proceed visually to land. I wouldn't forget about the arc, rather I'd probably be thinking about the 10 DME arc in the back of my mind. :)

 

Though outside of training, I'd shoot one of the other approaches (LOC/LDA/RNAV) as they all have lower mins.

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1200 ft has nothing to do with it. You can abandon an instrument approach and proceed visually at any point (assuming certain criteria are met). However, yes, on this approach, if I saw the airport and could proceed visually to land. I wouldn't forget about the arc, rather I'd probably be thinking about the 10 DME arc in the back of my mind. :)

 

Though outside of training, I'd shoot one of the other approaches (LOC/LDA/RNAV) as they all have lower mins.

 

Right, thanks!

And yeah, the 1200 was just an "example", what I meant is that say you break out of the clouds at some point before the MAP and see the field, then you'd proceed visually, if you happen to lose visual contact you'd have to fly the missed approach as by the chart. When you say "10 DME", did you mean "11", the missed approach arc?

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I flew an FSEconomy assignment in X-Plane yesterday into Castlegar CYCG (Canada), which has a fun altitude drop over the hill and then a turn to line up with the runway down in the valley. This was flying a Turbo Goose so it was easy, but it's a challenge for anything fast and heavy.

 

 

castlegar.jpg

The fact that there is no runway number in the title of the approach should indicate to you that this is a circling approach, which means that nobody is expected to be able to line up with or descend for any particular runway with normal maneuvers directly from this approach. What you are actually supposed to do is enter a circling maneuver, a visual traffic pattern, for one of the runways upon sighting the airport.

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That approach into KMTN... military jet only. That's why it's not in the G1000.

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That approach into KMTN... military jet only. That's why it's not in the G1000.

Why do you say that?

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To be honest, I don't remember the 'why'... I just remember it coming up once with a training facility.

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To be honest, I don't remember the 'why'... I just remember it coming up once with a training facility.

 

Well it says VOR/DME "or" TACAN, note the "or".

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Here's one from the old Avon STOLPort near Vail, CO...

 

WHR_id_r28_zps50mti4ix.jpg

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Right, thanks!

And yeah, the 1200 was just an "example", what I meant is that say you break out of the clouds at some point before the MAP and see the field, then you'd proceed visually, if you happen to lose visual contact you'd have to fly the missed approach as by the chart. When you say "10 DME", did you mean "11", the missed approach arc?

 

Yeah, 11.. sorry... typo... was still on my first cup of coffee. :)

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That approach into KMTN... military jet only.

Nothing on the approach plate that would suggest it is a military-only approach and as a pilot I have to go by what info is in front of me. The airport is not restricted to military traffic only.

The main reason it is not in G1000 is that Garmin doesn't support final approach course being a curve.

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Yeah... no... it's not in the raw database either... which doesn't care about Garmin one bit.

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Yeah... no... it's not in the raw database either... which doesn't care about Garmin one bit.

 

The VOR/DME or TACAN Z RWY 15 into MTN is not a military only procedure. I don't know why it's not in the raw database, but that doesn't preclude it being available for civilian use.

 

Without doing more digging, the only thing that immediately comes to mind is AC 90-108 - Use of Suitable Area Navigation (RNAV) Systems on Conventional Routes and Procedures which is what allows using RNAV (GPS) in lieu of DME. The language has made it into the AIM, specifically 1-2-3-c (Note: 4):

 

Pilots may not substitute for the NAVAID (for example, a VOR or NDB) providing lateral guidance for the final approach segment.

 

MTN is a rare approach (with an arc as the final approach segment). Here's my blind leap (which may be incorrect)...Since RNAV/GPS is being used in lieu of DME, and DME is what is providing lateral guidance on the final approach segment, it's not authorized.

 

This still doesn't necessarily explain why it's left out of the raw database. It's been awhile (years) since I've dug into RTCA specs & requirements. I'm not sure if there is a database flag that prevents an approach from being flown until certain sensors are present (i.e. what if I'm in a a/c WITH a separate DME, and want to display an approach overlay for SA?). Perhaps they don't include it in the database to prevent someone using the approach in GPS mode when it's obviously not authorized due to the final segment?

 

Don't know.. spitballing here. Would need more time to dig deeper.

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Yeah... no... it's not in the raw database either... which doesn't care about Garmin one bit.

The VOR/DME or TACAN Z at KMTN isn't in any nav databases because it doesn't conform to ARINC rules. IIRC, you can't code Arc-Fix (AF) path terminators on the final approach segment (for a non-precision inside the FAF). 

 

Here's some of my favorites:

How to fail a checkride: KROW HI-ILS RWY 21

Using a Localizer at a different airport: KNZY LOC/DME-A

5-Mile visibility required for LNAV/VNAV mins: KTVC RNAV (GPS) RWY 08

The steepest descent gradient I've seen in CONUS: KDVT RNAV (GPS)-B (there's a reason it's circling only!)

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The steepest descent gradient I've seen in CONUS: KDVT RNAV (GPS)-B (there's a reason it's circling only!)

 

Stepping out of CONUS...and a non-circling... I see your 6.8 degrees, and raise you 9.3 degrees:

 

VNKT VOR DME RWY 02

 

BTW: Thanks for the ARINC clue... Didn't think about encoding fixes in the database...

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Stepping out of CONUS...and a non-circling... I see your 6.8 degrees, and raise you 9.3 degrees:

That's actually not 9.3°...its 9.3%, which works out to only 5.3°. Interestingly, the Nepal plate you provided lists this as 5.5°, but the Jepp lists it as 5.3°, which matches my math. Additionally, from 3.0 DME to the runway you intercept the standard 3.0°.

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ExNusquam, great plates you got there! I will try them out with the 777 and see how it goes, what do you think?

 

 

 


How to fail a checkride: KROW HI-ILS RWY 21

 

Or how to learn the difference between "at or above", "at or below" and "at"

 

 

 


Using a Localizer at a different airport: KNZY LOC/DME-A

 

Someone must have accidentally landed at San Diego.

 

 

 


5-Mile visibility required for LNAV/VNAV mins: KTVC RNAV (GPS) RWY 08

 

But why? What's the point?

 

 

 


The steepest descent gradient I've seen in CONUS: KDVT RNAV (GPS)-B

 

So if your Vapp was, say, 140kt, what would the descent rate be? Something like 1900 ft/min I calculated.

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That's actually not 9.3°...its 9.3%, which works out to only 5.3°. Interestingly, the Nepal plate you provided lists this as 5.5°, but the Jepp lists it as 5.3°, which matches my math. Additionally, from 3.0 DME to the runway you intercept the standard 3.0°.

 

You're right...Damn attention to detail after a bottle of wine...

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But why? What's the point?

Long answer short, a non-temperature compensating Baro-VNAV system will fly a shallower glide-path on cold days, and the procedures are designed to provide safe obstacle clearance even on the average coldest day of the year for that airport. I'm guessing one of the many towers near the final course is close enough to final to necessitate a DA that's 1359' above the threshold. The visibility requirement is high so you can actually see the runway at that altitude. 

 

 

 


So if your Vapp was, say, 140kt, what would the descent rate be? Something like 1900 ft/min I calculated.

6.8°=721.1 ft/NM. 

 

(721.1 ft/1 NM) * (140 NM/60 Min)

NM cancel. Answer should be 1682.6 ft/Min.

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