Cessna 208B crash short of Burley Municipal Airport

FlightmechH3

FlightmechH3

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FlightmechH3
On top of a potato processing plant.

Sounds like light snow could have been a factor. RIP
 
Less than half a nm from the threshold, it appears. UPS freight ship, 30-year-old pilot Brittney Infanger killed.
 
It looks like she clipped the 60' tall silos. Very low considering the distance to the threshold.

Can anyone confirm that she made a go-around before the incident?
 
flightwriter said:
A fair chance, I think, given the C208's history with ice. The accident aircraft was a 2013 model and would've been equipped with TKS.
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One would hope that; it was a relatively pricy option. But then again, sooooo close.
 
This is what ForeFlight synthetic vision would show at 4300' on the RNAV 20...
KBYI-4300ft.PNG
 
That's terrible. Why the heck would they build tower structures on approach, so close to the runway. Family is right. Someone should answer for their decision. Condolences.
 

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DavidWhite said:
Wrong altimeter setting maybe?
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So many things can cause us to be a bit off on an approach. Flying is dangerous despite what we tell ourselves....but having idiots built silos on a Non Precision LNAV approach seems moronic. MDA is 4560 and the silos are 4405. That is not much room for error and a young lady lost her life.
 
Flying Doc said:
So many things can cause us to be a bit off on an approach. Flying is dangerous despite what we tell ourselves....but having idiots built silos on a Non Precision LNAV approach seems moronic. MDA is 4560 and the silos are 4405. That is not much room for error and a young lady lost her life.
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The obstacles that are 4405 MSL (if you're getting that from the sectional chart) are ~4 nm from the airport and are prior to the stepdown fix JAMID, which has a minimum altitude of 4800, which meets clearance criteria.

The obstacles in your picture are not those 4405 obstacles.
 
I fly into that airport with some regularity. I like using it for the IFR Cross Country training flights. However I recall only shooting an approach from that direction in IMC once, and that was back when it was a VOR/DME approach. We never saw the airport and went missed. I tend to use the VOR approach from the West as it is one of the few in our area with that kind of layout..

One of the local news articles quoted a local pilot as saying the problem with that approach isn't the stacks themselves, but steam/smoke often comes from the stacks which makes the visibility on the approach much worse than reported.

Brian
CFIIG/ASEL
 
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Don't forget, the FlightAware altitude is a pressure altitude and is not an MSL altitude. Need to know the altimeter setting at the time to adjust to MSL.
 
RussR said:
The obstacles that are 4405 MSL (if you're getting that from the sectional chart) are ~4 nm from the airport and are prior to the stepdown fix JAMID, which has a minimum altitude of 4800, which meets clearance criteria.

The obstacles in your picture are not those 4405 obstacles.
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All good details. Thanks. However one of the flying instructions to new pilots and I forget where I read this. Do not fly over smoke stacks that are active as heat can generate turbulence and visibility can be reduced. Coming out of a cloud into this can be very distracting.
 
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Some more on this…sad story RIP

Edit duplicate posting of above link at the same time…
 
In depth investigation by Dan Gryder.

He got the light. It was red and not the required high intensity. The company told the EPA one height and the FAA another height because both wanted different things. The FAA had already found seven other obstacles that were too high for the approach to be legal. The city went and unplugged the VASI because they knew it would fly people into the stack.

This approach should have been shut down before the crash. FAA, the company, and the city should be liable IMO.

 
Bonchie said:
In depth investigation by Dan Gryder.

He got the light. It was red and not the required high intensity. The company told the EPA one height and the FAA another height because both wanted different things. The FAA had already found seven other obstacles that were too high for the approach to be legal. The city went and unplugged the VASI because they knew it would fly people into the stack.

This approach should have been shut down before the crash. FAA, the company, and the city should be liable IMO.

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What does, and does not, ruffle the FAAs feathers is infuriating. Opposites day, every day.
 
Bonchie said:
In depth investigation by Dan Gryder.

He got the light. It was red and not the required high intensity. The company told the EPA one height and the FAA another height because both wanted different things. The FAA had already found seven other obstacles that were too high for the approach to be legal. The city went and unplugged the VASI because they knew it would fly people into the stack.

This approach should have been shut down before the crash. FAA, the company, and the city should be liable IMO.

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There's a whole thread on the video. Stop taking Gryder as gospel. What he doesn't and can't know he just makes up to fit a narrative. It takes longer than a couple weeks to do an in depth investigation and put together and edit a video.

https://www.pilotsofamerica.com/community/threads/gryder.138030/
 
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There are a lot of errors in the video analysis. First, the advisory GP does not change for the procedure, it remains at 3.75 degrees, which crosses HIKLO nominally at 6206 feet and JAMID at 4832 feet. The assertion that the GP changes after JAMID is false and manufactured. I used the chart information and the equations used by the FAA to determine the GP height at a distance from the threshold. They take the curvature of the earth into account. The TSO requires that the advisory GP clear all step down fixes and that it is a constant angle. I simulated this using the GTN trainer and took screenshots of the indications at the advisory GP intercept at 7000 feet, which my calculations indicate would occur approximately at 2 NM before crossing HIKLO.

Here is the screenshot close to GP intercept.

gs intercept.jpg


Here is the screenshot close to crossing HIKLO (my calculation is it should occur at 6206)

hiklo.jpg

Here is the screenshot close to crossing JAMID (my calculation is it should occur at 4832)

jamid.jpg

The advisory GP is not suited for descent below the MDA, so any descent to the runway must be visual. The inoperative VASI is shown in the AFD as being 3.5 degrees with a TCH of 46 feet and a displaced threshold of 305'. Although there is an FDC NOTAM to delete the note regarding the VGSI difference, there isn't a NOTAM indicating that the VASI is out of service, so the current chart still displays a VASI and the AFD still indicates it is in service.
 
John Collins said:
There are a lot of errors in the video analysis. First, the advisory GP does not change for the procedure, it remains at 3.75 degrees, which crosses HIKLO nominally at 6206 feet and JAMID at 4832 feet. The assertion that the GP changes after JAMID is false and manufactured. I used the chart information and the equations used by the FAA to determine the GP height at a distance from the threshold. They take the curvature of the earth into account. The TSO requires that the advisory GP clear all step down fixes and that it is a constant angle. I simulated this using the GTN trainer and took screenshots of the indications at the advisory GP intercept at 7000 feet, which my calculations indicate would occur approximately at 2 NM before crossing HIKLO.

Here is the screenshot close to GP intercept.

View attachment 107071


Here is the screenshot close to crossing HIKLO (my calculation is it should occur at 6206)

View attachment 107072

Here is the screenshot close to crossing JAMID (my calculation is it should occur at 4832)

View attachment 107073

The advisory GP is not suited for descent below the MDA, so any descent to the runway must be visual. The inoperative VASI is shown in the AFD as being 3.5 degrees with a TCH of 46 feet and a displaced threshold of 305'. Although there is an FDC NOTAM to delete the note regarding the VGSI difference, there isn't a NOTAM indicating that the VASI is out of service, so the current chart still displays a VASI and the AFD still indicates it is in service.
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Lot’s more about this starting around post #111 here https://www.pilotsofamerica.com/community/threads/gryder.138030/page-3
 
John Collins said:
There are a lot of errors in the video analysis. First, the advisory GP does not change for the procedure, it remains at 3.75 degrees, which crosses HIKLO nominally at 6206 feet and JAMID at 4832 feet. The assertion that the GP changes after JAMID is false and manufactured. I used the chart information and the equations used by the FAA to determine the GP height at a distance from the threshold. They take the curvature of the earth into account. The TSO requires that the advisory GP clear all step down fixes and that it is a constant angle. I simulated this using the GTN trainer and took screenshots of the indications at the advisory GP intercept at 7000 feet, which my calculations indicate would occur approximately at 2 NM before crossing HIKLO.

Here is the screenshot close to GP intercept.

View attachment 107071


Here is the screenshot close to crossing HIKLO (my calculation is it should occur at 6206)

View attachment 107072

Here is the screenshot close to crossing JAMID (my calculation is it should occur at 4832)

View attachment 107073

The advisory GP is not suited for descent below the MDA, so any descent to the runway must be visual. The inoperative VASI is shown in the AFD as being 3.5 degrees with a TCH of 46 feet and a displaced threshold of 305'. Although there is an FDC NOTAM to delete the note regarding the VGSI difference, there isn't a NOTAM indicating that the VASI is out of service, so the current chart still displays a VASI and the AFD still indicates it is in service.
Click to expand...
The advisory GP not being suited for descent below the MDA is a given. But what about at the FAF and a Step-down Fix after that? If on a Glideslope, you can cross those below their minimum altitude. But what about these advisory GP’s? I think the rule is you still have to comply with the altitudes. So what effect might have temperature and altimeter setting had? What was the temperature? How old and accurate was the altimeter setting? Almost an hour old maybe. Had pressure been rising or falling rapidly? What reaction may have there been when realizing you were going to get to 4800 before reaching JAMID?
 
You do have to comply with the indicated altitude on an advisory GP. On a cold day, following the advisory GP will place the aircraft above the indicated altitude due to the fact that the GP does not move, but the altitude indication is higher than the true altitude, so the indication will be above the crossing altitude if you are on GP. On a hot day, the reverse is true, that is the altitude indication is below the true altitude, so in theory, one may have to pause the descent on the advisory GP until past the step down or FAF fix. Of course on a colder than ISA day, the real issue is that the MSL indicated altitude is above the true altitude, so you have less obstacle clearance as you will hit an obstacle at its true altitude. I think as a practical matter, if you are within 100 feet of the crossing altitude, it is probably legal and regardless, the only way to spot a deviation is if there is either a DPE on board or you deviate by more than 200 feet to show up on radar or ADS-B. The only place where there is a high risk of a PD for busting a crossing altitude while following a GP/GS/Advisory GP is on a hot day and well outside the FAF. The closer you are to the runway, the less error that is introduced by temperature if you have an accurate altimeter setting from the airport.
 
John Collins said:
You do have to comply with the indicated altitude on an advisory GP. On a cold day, following the advisory GP will place the aircraft above the indicated altitude due to the fact that the GP does not move, but the altitude indication is higher than the true altitude, so the indication will be above the crossing altitude if you are on GP. On a hot day, the reverse is true, that is the altitude indication is below the true altitude, so in theory, one may have to pause the descent on the advisory GP until past the step down or FAF fix. Of course on a colder than ISA day, the real issue is that the MSL indicated altitude is above the true altitude, so you have less obstacle clearance as you will hit an obstacle at its true altitude. I think as a practical matter, if you are within 100 feet of the crossing altitude, it is probably legal and regardless, the only way to spot a deviation is if there is either a DPE on board or you deviate by more than 200 feet to show up on radar or ADS-B. The only place where there is a high risk of a PD for busting a crossing altitude while following a GP/GS/Advisory GP is on a hot day and well outside the FAF. The closer you are to the runway, the less error that is introduced by temperature if you have an accurate altimeter setting from the airport.
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I've heard that this problem led to an airline crew getting violated because they busted one or more stepdown altitudes, due to following the LAX glideslope well outside the charted glideslope intercept point.
 
John Collins said:
You do have to comply with the indicated altitude on an advisory GP. On a cold day, following the advisory GP will place the aircraft above the indicated altitude due to the fact that the GP does not move, but the altitude indication is higher than the true altitude, so the indication will be above the crossing altitude if you are on GP. On a hot day, the reverse is true, that is the altitude indication is below the true altitude, so in theory, one may have to pause the descent on the advisory GP until past the step down or FAF fix. Of course on a colder than ISA day, the real issue is that the MSL indicated altitude is above the true altitude, so you have less obstacle clearance as you will hit an obstacle at its true altitude. I think as a practical matter, if you are within 100 feet of the crossing altitude, it is probably legal and regardless, the only way to spot a deviation is if there is either a DPE on board or you deviate by more than 200 feet to show up on radar or ADS-B. The only place where there is a high risk of a PD for busting a crossing altitude while following a GP/GS/Advisory GP is on a hot day and well outside the FAF. The closer you are to the runway, the less error that is introduced by temperature if you have an accurate altimeter setting from the airport.
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Yeah. If you have an accurate altimeter setting. I’m wondering if all the +/- errors, altimeter setting, temperature and inherent altimeter error all leaned in the same direction how big it might be.
 
Palmpilot said:
I've heard that this problem led to an airline crew getting violated because they busted one or more stepdown altitudes, due to following the LAX glideslope well outside the charted glideslope intercept point.
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Those were fixes way out yonder and up kinda high. They’ve rebuilt the Approaches to make it not much of a factor anymore.
 
John Collins said:
The assertion that the GP changes after JAMID is false and manufactured.
Click to expand...

I also confirmed this with Garmin's GNX and GTN simulators.

However, an earlier version of their simlator (which I lost access to when i upgraded last week), and I suspect, older nav units do follow different slopes for that approach. Someone with a G1000 simulator verified this and posted on the thread referenced above byu luvflyin. This isn't 100% verified perhaps but should be investigated further before dismissing.
 
I'd like to get some clarification on John Collins post above (#31), and ask a question. He refers to the "indicated altitude" and the "advisory GP" altitude.

I think by "indicated" he means "altimeter reading with proper baro setting for the airport", right? And by "advisory", he means a WAAS altitude from the GPS receiver, correct?

So to check my understanding, a WAAS-derived altitude is true MSL, accurate to a couple of meters, unaffected by atmospheric conditions. The altimeter reading, even with the proper setting for the airport can differ from true MSL as a function of temperature, and the deviation gets worse with increasing altitude above the field, but the altimeter will read correctly on the field.

So my question is this: where does the FAA state that you must follow the advisory GP? I'm not arguing, just asking the question. That makes sense to me if WAAS gives accurate, true MSL, but where does the FAA require this? I am reading AC120-108 and it's not obvious to me in that document. There is one note in subparagraph 6(d)(3):

NOTE: During any approach, pilots should perform a continuous descent flight path that meets all altitude constraints.

But that seems ambiguous as to what source is being used to determine altitude. FAA has so many publications that I wouldn't know where to find more on this topic.
 
Turbo-Arrow-Driver said:
However, an earlier version of their simlator (which I lost access to when i upgraded last week), and I suspect, older nav units do follow different slopes for that approach. Someone with a G1000 simulator verified this and posted on the thread referenced above byu luvflyin. This isn't 100% verified perhaps but should be investigated further before dismissing.
Click to expand...

They are going to comply with the TSO and it will use a single GP value. The TERPS says this:

calculate vda when step down fix is used.jpg
use step down fix with greater angle than faf to determine vda.jpg

Original Procedure with VDA defined from JAMID to be 3.75 degrees and a TCH of 40 using the guidance above method

VDA from original procedure bassed on JAMID.jpg
 
Turbo-Arrow-Driver said:
I'd like to get some clarification on John Collins post above (#31), and ask a question. He refers to the "indicated altitude" and the "advisory GP" altitude.

I think by "indicated" he means "altimeter reading with proper baro setting for the airport", right? And by "advisory", he means a WAAS altitude from the GPS receiver, correct?

So to check my understanding, a WAAS-derived altitude is true MSL, accurate to a couple of meters, unaffected by atmospheric conditions. The altimeter reading, even with the proper setting for the airport can differ from true MSL as a function of temperature, and the deviation gets worse with increasing altitude above the field, but the altimeter will read correctly on the field.

So my question is this: where does the FAA state that you must follow the advisory GP? I'm not arguing, just asking the question. That makes sense to me if WAAS gives accurate, true MSL, but where does the FAA require this? I am reading AC120-108 and it's not obvious to me in that document. There is one note in subparagraph 6(d)(3):

NOTE: During any approach, pilots should perform a continuous descent flight path that meets all altitude constraints.

But that seems ambiguous as to what source is being used to determine altitude. FAA has so many publications that I wouldn't know where to find more on this topic.
Click to expand...

The FAA does not state you must follow the advisory GP. With dive and drive, you are very likely to be below the advisory GP and that is permitted. The advisory GP is simply a guide or one way of descending after passing a fix at or above a minimum crossing altitude to the next minimum altitude. It is not the only way.
 
Turbo-Arrow-Driver said:
I'd like to get some clarification on John Collins post above (#31), and ask a question. He refers to the "indicated altitude" and the "advisory GP" altitude.

I think by "indicated" he means "altimeter reading with proper baro setting for the airport", right? And by "advisory", he means a WAAS altitude from the GPS receiver, correct?

So to check my understanding, a WAAS-derived altitude is true MSL, accurate to a couple of meters, unaffected by atmospheric conditions. The altimeter reading, even with the proper setting for the airport can differ from true MSL as a function of temperature, and the deviation gets worse with increasing altitude above the field, but the altimeter will read correctly on the field.

So my question is this: where does the FAA state that you must follow the advisory GP? I'm not arguing, just asking the question. That makes sense to me if WAAS gives accurate, true MSL, but where does the FAA require this? I am reading AC120-108 and it's not obvious to me in that document. There is one note in subparagraph 6(d)(3):

NOTE: During any approach, pilots should perform a continuous descent flight path that meets all altitude constraints.

But that seems ambiguous as to what source is being used to determine altitude. FAA has so many publications that I wouldn't know where to find more on this topic.
Click to expand...
I understand the altitudes thing as you do. I have never seen anything that says you must follow the advisory GP. I think the name speaks for itself. But they’ve given a lot of advice on why you shouldn’t follow it, exactly, all the way down sometimes.
 
luvflyin said:
I understand the altitudes thing as you do. I have never seen anything that say you must follow the advisory GP. I think the name speaks for itself. But they’ve given a lot of advice on why you shouldn’t follow it, exactly, all the way down.
Click to expand...

My understanding is it will take you down like a ILS, hitting every altitude constraint on the dot, HOWVER when you hit MDA you level off and you’re VFR mode or you’re TOGA at the missed.

Doing a 100% visual landing appears to be even more important after now seeing the FAA will not deactivate illegal approaches, or take legal action, it’s all carrot no stick.
 
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