Is there something I'm missing about this approach?

Tinstafl

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Tinstafl
So, obviously there is, but I'm trying to figure out if there is a charting difference for Canadian procedures or if I'm actually just missing something basic that I've forgotten...

This comes from a Flightchops video for a circling approach at CZBA (RNAV 32)

It's an interesting video for several reasons but I'm focused on his descent below his vectored altitude prior to being established on a charted portion of the approach. He's vectored at 3,000 to BOXAN (the IF) and cleared for the approach. The 3,000 is already below the MSA but that's fine since he's being vectored. Prior to reaching BOXAN he turns inbound (again, fine), but initiates his descent down toward the "Recommended" BOXAN to VIKTO altitude. I don't see any notes that indicate this is a part of the procedure. There is the 2,600 shown from MESNO but that's not where he is inbound from. I would have said he needed to maintain 3,000 until BOXAN and only then cleared down to the VIKTO altitude of 1,590 or maintain 2,600 until intercepting the advisory glideslope.

What am I missing? This isn't a criticism of what he does. I'm expecting this is either something about how the video was edited or, more likely, a brain-fart on my end and I am missing something. Any thoughts appreciated.
 
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Ben to Kitchener IFR but I don't keep them current.
Wanna publish the plate- most of use don't have Transp. CA plates?!
 
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sure, I think I can post an image shortly. You can see it in the video, but it’s a little bit blurry. I don’t have a subscription either, but I think I can get a copy from a friend.
 
Nah, just set yourself up in a left-hand 27.4 degree arc on final for Runway '3to36' and a right-hand 24.8 degree arc for '15to18'.
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Oh, and avoid the terrain on either side.
 
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He even says "I'm going to force it on down to 2800 to make sure it begins the descent" or something like that.

From what I can find, Canada uses TERPS, virtually identical to the US. So I know something about that.

I can't see any way that early descent would be allowed. Seems like an error on the pilot's part, perhaps a misunderstanding of when to begin descent.

You should write a comment on the video and ask about it, I'd be curious to know his response.
 
Thanks @MauleSkinner - It caught me for a few reasons. One, FlightChops is usually very conscientious about how he presents his errors, but also because there are just some small variations in what and how information is shown on the chart. I'm not used to seeing a VDA listed and most RNAV approaches I can think of will chart some sort of crossing restriction at a fix like BOXAN. Which isn't the case here. And falling back to the MSA doesn't shed light either. And a "Recommended" altitude is strange also.

It's just enough head scratching that I want to dig in to figure out if I have a gap in my knowledge. Or maybe a Canadian pilot can shed some light on what might be different.

I probably will end up flying internationally before too long and obviously need to be up to speed on these kinds of variances.
 
Thanks @RussR. I thought about it but I usually just steer clear of posting to places like YouTube because the viewer group is usually so uninformed that it turns into a typical social media mess, degenerating into an insult war over something simple. Technical forums like this seem more productive and worthwhile.
 
Thanks @RussR. I thought about it but I usually just steer clear of posting to places like YouTube because the viewer group is usually so uninformed that it turns into a typical social media mess, degenerating into an insult war over something simple. Technical forums like this seem more productive and worthwhile.
I agree that YouTube comments sections are typically wastelands of misinformation. However, it seems from this video and others that he actually does participate in the comments section and responds to questions and comments. Since the only person who knows why he descended is him, asking him there seems like a reasonable option.
 
Yeah - I wish it was a world where people didn't love to play gotcha with good pilots who make honest mistakes.

I'll find a way to DM him directly.
 
I’m not sure how relevant this is here, but does Canada use the post TWA/Dulles approach clearance language like we do.

How many of you know what I am alluding to?
 
The longer I look at this chart the more odd it becomes. It makes it look like you could legally fly BOXAN to VIKTO at 1,200. Only 80 feet above the MDA (and 600’ agl … :: gulp :: that can’t be right) all the way from 8 miles out) to the MAP and below the glideslope intercept altitude (I know it’s advisory only) at the FAF.

uhhhh…I’m definitely missing something regardless of whether or not Steve squeaked down too early.
 
The longer I look at this chart the more odd it becomes. It makes it look like you could legally fly BOXAN to VIKTO at 1,200. Only 80 feet above the MDA (and 600’ agl … :: gulp :: that can’t be right) all the way from 8 miles out) to the MAP and below the glideslope intercept altitude (I know it’s advisory only) at the FAF.

uhhhh…I’m definitely missing something regardless of whether or not Steve squeaked down too early.
Dive and drive?
 
Yeah for sure. On that note it does say NA for Cat D…

Could you fly at 600’ for 8 miles under a cloud deck? Sure of course. Not a big deal on a practical level really. IN a cloud deck? That would get my attention a little bit more… and I just wouldnt expect an approach to be effectively designed that way.

I just really have a hard time believing I’m interpreting some of the details of the plate correctly. It doesn’t line up at all with how my brain expects approaches to be designed. Or with what I expect to read on a plate. And I’m generally only an occasional idiot … or at least not a full time dummy. So I’m temporarily bamboozled.
 
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Anyhow, that’s somewhat of a rabbit trail from my original question. I love the minutiae of approaches and plates and TERPS obviously.

But good to know that what stuck out to me in the video was not just missing a detail. I’ll see if i get an answer from FlightChops. Hopefully he doesnt think I’m playing gotcha.
 
The Jepp was posted above. FWIW, this is the Canadian chart. (For those who don’t know, FltPlan has them available.) According to the Canadian approach chart legend, the shaded area represents the minimum altitude for that segment.

Edit: just watched the video. The only question I have is where the descent to 2800 before reaching BOXAN came from.

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I’m not sure how relevant this is here, but does Canada use the post TWA/Dulles approach clearance language like we do.

How many of you know what I am alluding to
"post TWA/Dulles approach clearance language" . . . well I can BooglehooTM
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Hey folks, we are talking about this just shortly after the golden anniversary of this unfortunate event! I wonder if anyone has even thought about the anniversary or if it’s getting lost to history.

Canadian pilots out there does a Canadian approach clearance include an altitude limit till established?
 
The Jepp was posted above. FWIW, this is the Canadian chart. (For those who don’t know, FltPlan has them available.) According to the Canadian approach chart legend, the shaded area represents the minimum altitude for that segment.

Edit: just watched the video. The only question I have is where the descent to 2800 before reaching BOXAN came from.

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Thanks for that. Yep, that clarifies/confirms some things for me. My read of the Jepp chart seems “on course”. The differences seem within the range of normal procedures if a bit different than what I consider “normal”.

So yeah, just that decision to descend prior to BOXAN. We’ll see if any Canadians show up for that question.
 
Thanks for that. Yep, that clarifies/confirms some things for me. My read of the Jepp chart seems “on course”. The differences seem within the range of normal procedures if a bit different than what I consider “normal”.

So yeah, just that decision to descend prior to BOXAN. We’ll see if any Canadians show up for that question.
One more piece to the final approach course. The Jepp charts shows the 2600' altitude as "recommended." If you look at a Canadian chart legend, you'll see that's essentially correct. It's called an "initial altitude" but what it is is the altitude that will allow you to capture the glidepath early and comfortably. It's basically a CDFA stabilized descent target. That's why FlightChops wanted to get down to at least 2800, any higher and, with turn anticipation, he'd be above the glidepath by the time he rolled out from the turn to final.

What I couldn't tell about the 2800 is exactly where he started down. I can envision, for example, being in the turn anticipation area and pushing the 1st 200' of the descent as easily as I can imagine doing it too far in advance. And, of course, there could have been a 2800' instruction that was edited out.
 
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Hey folks, we are talking about this just shortly after the golden anniversary of this unfortunate event! I wonder if anyone has even thought about the anniversary or if it’s getting lost to history.

Canadian pilots out there does a Canadian approach clearance include an altitude limit till established?
Even the the US it's a "sometimes," although most US ATC will tend to give one even when not necessary. I discuss that a bit in my IFR Magazine article, "Gettin' Down" (no paywall for this one)
 
I think in another quick but careful review of the sequence, he's very very close to BOXAN when he "forces" it down. It was simply his statement of "I'm not quite at BOXAN yet and I'm gonna force it down to begin the descent" that flagged it for me. It seems like one of those things where it may or may not have been a technical error, and those things are worth discussing, but it boils down to splitting some pretty fine hairs in this case. And he may have been cleared to descend which negates all of that anyway.

At least I'm walking away with a little better understanding of Canadian approach plates.
 
He even says "I'm going to force it on down to 2800 to make sure it begins the descent" or something like that.

From what I can find, Canada uses TERPS, virtually identical to the US. So I know something about that.

I can't see any way that early descent would be allowed. Seems like an error on the pilot's part, perhaps a misunderstanding of when to begin descent.

You should write a comment on the video and ask about it, I'd be curious to know his response.
If I remember right, in Canada you may descend to the MSA when you get the Approach Clearance. Unlike the US where the MSA is an emergency safe altitude, in Canada it is a 'procedural' altitude. There was a thread here a coupla years or so ago about this. It was a US airport but Canada ran the Approach. It was a fly in to the airport at a resort/hotel place. I think it was Minneapolis Center that delegated the airspace there to Canada. The OP had got an Approach Clearance that did not include an altitude to maintain until established on a published segment. I'll try to find it but I don't always have good luck doing POA searches. Hopefully someone remembers it and can find it.
 
If I remember right, in Canada you may descend to the MSA when you get the Approach Clearance. Unlike the US where the MSA is an emergency safe altitude, in Canada it is a 'procedural' altitude. There was a thread here a coupla years or so ago about this. It was a US airport but Canada ran the Approach. It was a fly in to the airport at a resort/hotel place. I think it was Minneapolis Center that delegated the airspace there to Canada. The OP had got an Approach Clearance that did not include an altitude to maintain until established on a published segment. I'll try to find it but I don't always have good luck doing POA searches. Hopefully someone remembers it and can find it.
I think you are correct that, in our jargon, the Canadian MSA is a "published altitude" like our TAA. But that doesn't help with this question since the last assigned altitude (in the video), 3000, is below the 3100 MSA.
 
I think you are correct that, in our jargon, the Canadian MSA is a "published altitude" like our TAA. But that doesn't help with this question since the last assigned altitude (in the video), 3000, is below the 3100 MSA.
Yeah. I was mostly replying to Russ's Canada's TERPs is pretty much the same as the US. It brings up questions about this Approach. They had him at 3000. Would you climb to 3100 when you got Cleared?? I wouldn't have. I think maybe their rule is that if the plane is below the MSA, then an altitude to maintain until established must be given and the Controller didn't?? None of that changes that the OP did descend prematurely regardless.
 
Yeah. I was mostly replying to Russ's Canada's TERPs is pretty much the same as the US. It brings up questions about this Approach. They had him at 3000. Would you climb to 3100 when you got Cleared?? I wouldn't have. I think maybe their rule is that if the plane is below the MSA, then an altitude to maintain until established must be given and the Controller didn't?? None of that changes that the OP did descend prematurely regardless.
I wouldn't. I think it's the same here and there. "Cleared for the Approach" means you may descend from your last assigned altitude to a published altitude.

The video suggests he may have descended prematurely. But as mentioned in the discussion with @Tinstafl (btw, I love that handle), I'm not certain he did.
 
and yeah, it’s still a little bit ambiguous.
If you are talking about that picture from the AIM, what's ambiguous? There are really only three differences from our rules. One is the use of the MSA as an operational altitude. The other two are (d) & (e). The US doesn't have an equivalent for (d), which is published on the approach chart. I suspect (e) is about IFR flight in uncontrolled airspace.
 
If I remember right, in Canada you may descend to the MSA when you get the Approach Clearance. Unlike the US where the MSA is an emergency safe altitude, in Canada it is a 'procedural' altitude. There was a thread here a coupla years or so ago about this. It was a US airport but Canada ran the Approach. It was a fly in to the airport at a resort/hotel place. I think it was Minneapolis Center that delegated the airspace there to Canada. The OP had got an Approach Clearance that did not include an altitude to maintain until established on a published segment. I'll try to find it but I don't always have good luck doing POA searches. Hopefully someone remembers it and can find it.
Great memory - and that was actually me which is what got me interested in this thread - the place was Piney Manitoba, North Dakota. Likely before 2016 - it’s been so long I’ll try to find the string as well.
 
If you are talking about that picture from the AIM, what's ambiguous? There are really only three differences from our rules. One is the use of the MSA as an operational altitude. The other two are (d) & (e). The US doesn't have an equivalent for (d), which is published on the approach chart. I suspect (e) is about IFR flight in uncontrolled airspace.
No no, the AIM info that you posted is perfectly clear. And the discussion about the differences in Canada in general. I’m just talking about the exact interpretation of the FlightChops video.
 
I wouldn't. I think it's the same here and there. "Cleared for the Approach" means you may descend from your last assigned altitude to a published altitude.

The video suggests he may have descended prematurely. But as mentioned in the discussion with @Tinstafl (btw, I love that handle), I'm not certain he did.
He may not have but he intended to. Said Auto Pilot is in Approach mode cleared to descend, I'm at 3000 not quite to BOXON yet and I'm going to force it down to begin the descent toward 2800. Maybe by the time he got the buttons pushed and plane configured to descend he was at the point where a flyby descent could legally begin. At any rate it's no harm no foul. It's his home drome, he's shot the Approach many times. He picked 2800 instead of the recommended 2600 because he knew it would work.
 
I was interested enough in the question to ask Steve via the video comments. I received a response. We went back and forth a little. I could summarize, but the best bet is to go to the video and find our discussion if you are interested.
 
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