Pope:

Excellent post!

I doubt we will hear on the CVR from the PNF, "PAPI in sight."

Airbubba..Just repeating what a Birmingham controller wrote on a union blog....

Just out of curiosity, I projected this out to the see how much clearance would be afforded by this. I used the spot which JC identified on Google earth which everyone mocked him for. Turns out that a obstacle clearance plane of 2.2degrees would give a clearance of about 65 feet to an airplane exactly on a 3.2 degree PAPI, 3700 ft from the threshold. That's remarkably close to the clearance from the terrain which JC figured using Google earth. Granted, the first point of impact was quite a bit further out and lower than this, so this is only peripherally related to the accident. However it is interesting to note how little clearance you might have over a half mile from the threshold and perfectly centered on the PAPI.

Thanks for sharing it, most of what I know about the mishap outside of the NTSB briefings is similarly anecdotal.

Perhaps not a player with UPS but some of the A306's I flew years ago had FMS's with very limited memory and internationally some procedures would not be in the database or, even worse, waypoints and constraints would be missing. I flew with Sperry, Smiths and some other kind of FMS, I can't remember. I think UPS only uses the A306's domestically these days so maybe this isn't a problem anymore.

This is ridiculous. How could such an approach be allowed, especially at night, with such little terrain clearance? The threshold crossing height is 50ft; 6000ft/1nm further back, you only have another 50ft higher (100ft in total) to give 2W/2R on the PAPI, with wheels hanging probably 30ft below that?

Surprising isn't it? There's always the possibility that I misunderstood aterpster, but that's how it pencils out.

It will be interesting to see when more of the CVR is released. Considering the AP wasn't disengaged (or dis-engaged itself) until 1 second before it, one could wonder if they recognized the terrain issue in time to realize how low they really were. In context of the "black hole" visual anomaly, wouldn't it be rather ironic if lack of lighting and other visual features from the houses removed (for safety reasons) actually ended up contributing to the accident.

I really wonder if this still would have happened if there was some kind of marker lighting on hill where the cockpit currently resides or on the plateau towards the threshold.

I know I would rather have that to help judge the distance.

To be clear, the homes were purchased/removed for noise abatement, not safety.

Surprising ....but real....

As I posted before the last 1/2 to 1 mile you litteraly buze the hill all the ways down to the RWY. It is like doing a low flyby over a downhill slope to the rwy.

It has been several years since I have done that approach, so I can not really say how high above the terrain you are. But the first night I did that approach the only think that came to my mind was " Only sh.. that is close !!! and that is being on the Papi.
In my opinion, on a "normal approach" the ground appear that close when you are really close to crossing the threshold and not being 1/2 to 1 mile away from the rwy.

The Careful Enough Statement of a Problem -
 

....implies the solution.

"This is ridiculous. How could such an approach be allowed, especially at night, with such little terrain clearance? The threshold crossing height is 50ft; 6000ft/1nm further back, you only have another 50ft higher (100ft in total) to give 2W/2R on the PAPI, with wheels hanging probably 30ft below that?"

So I'm assuming that FAA is the authority that decides what specific approach parameters will be published as officially sanctioned (or otherwise designated as safe and effective). And that in the ordinary course of the business of regulation of civil aviation in the US, FAA will await the outcome of the NTSB investigation and report process, prior to changing the approach parameters. Or is this not correct: might FAA change the published approach parameters on an interim basis? Has this happened after other mishaps on final? (And I'm sorry if there is a term more technically appropriate than 'parameters' for the (evidently) altitude and/or glideslope limits.)

Also, is there some periodic review process by which FAA checks on whether approach corridor limits have been shown, through the experience of the aviators who flew them, to need adjustments? It is easy to have the sense that FAA has its hands full just keeping the creaky ship afloat, and things like checking for any needed updates to APP corridors is a luxury the taxpayers have neither demanded nor realized they need to pay for. How does it work?

obstacle clearance from FAF to VDP/MAP is SUPPOSED to be 250'

http://www.skybrary.aero/bookshelf/books/811.pdf

WillowRun 6-3, A-Squared, Capn Bloggs & All those who believe GoogleEarth Elevation/Hgt data:

GoogleEarth provides good approximations of real-earth elevations and is good for relative differences, but it cannot be considered accurate at any single location within confidence levels that you'd want to consider whether you have appropriate clearance or not for approach/dep procedure design. Sometimes it's spot on to the nearest metre, other times not. Depending on where the location is and also often where the location is in relation to nearby terrain and buildings, the elevations can easily be out by up to say ±8 mtrs / ±26.5ft. This is due to the various sources of the data and how the data is modelled. The positional referencing of the image data to WGS84 lat/longs however is far more accurate.
In a sense it's a bit like the FlightAware data, in that it's sampled from actual observations using available data sources. The data is not certified to a particular integrity level though and thus needs to be used and interpreted with care and qualifications, depending on the purpose.

If Capt Bloggs and ASquared calcs are actually more or less correct, then that will come out in the investigation as result of FLT inspection of the PAPIs and resurvey of the terrain and remaining obstacles near the crash site, as well as review of the procedure flown (as selected in the FMS and as flown). In any case, if as it seems to be that the aircraft was simply way too low at that point, the issues you raise may, or may not, in fact be relevant or significant.


ironbutt57:
Yes, you're right: obstacle clearance for an NPA (with a FAF) in the primary area of a final approach segment is 250' (246' actually, or 75m). Take the highest obstacle between the FAF and the MAPt, add the obstacle clearance margin (and any comfort buffer that the designers feel appropriate for whatever reason, including taking into account potential inaccuracy tolerances in the obstacle and terrain data they're using) and round up to the nearest 10' = MDA.
Use of stepdown fixes allow interim descent points in the final segment, obviously.

However, when flying on the VDA (or even dive & drive), once you get to the MDA, that's it: can't continue descent unless RWY in sight and intending to land, and from then on you're in the visual segment and obstacle clearance is up to the pilot.

See also the next bit.

For info: re Obstacle Clearance in the Visual Segment (of Charted APCHs):

Some time back ICAO mandated that all States should assess new and old procedures (when reviewed/amended) for obstacles in the visual segment - ie, between the MDA/DA and the THR (actually, 60m prior usually).
Basically this is done by assessing a pseudo surface at 1.12° less than the promulgated APCH angle. Safety assessments, mitigations (which could include removal or cutting down of obstacle) &/or amendments to the procedure would be required if an obstacle penetrated the visual segment surface. Safety assessment might also indicate additional mitigations, such as additional marking/lighting of obstacles / terrain in the visual segment - eg, like the hill area 1/2-1 mile prior to the runway - ref skysign's post #380).Aterpster can elaborate on current FAA implementations of this ruling if required (in addition to the analysis that they do of 34:1 surfaces).
In any cases, statements regarding obstacles in the visual segment and implications for pilots are contained in the FAA AIM (relevant extracts are in this thread).
Note also previous posts on the 1° clearance for the PAPIs when installed and calibrated as additional mitigation.


Missed Approach:
To those who have discussed the relevant techniques when reaching the MDA whether flying dive & drive (heavies seriously still doing that?) or CDFA (or even DDA = MDA+50 for CANPA technique):
Unless the operator has a specific approval to do otherwise, the MDA is a legal minimum and busting it is a serious no-no.

With regard to this thread though, they'd gone well past the MDA and info provided by NTSB indicates that they were proceeding to land, so further discussion of handling the missed in this case is irrelevant.


ATerpster:

Thx for trying to correct the various misunderstandings of the different types of APCHs with regard to LNAV, LNAV/VNAV, RNAV GNSS APV, LPV, RNAV RNP AR, etc. Saved me some time. Well done on providing all of the other relevant AFM and FAA material for reference too.
Ian W: If, after reading Aterpster's reply and other material from qualified sites, then you could continue the discussion on the TechLog, but not in this thread as those issues are irrelevant here.

Given that the UPS cargo area is at the south west end of 6/24 I can't see any reason at all why anyone would choose to land a widebody on a shorter, narrower runway with less navaids and a two and a half mile taxi to get where you need to be. :confused:

Which brings up another point about the flight planning on UPS1354. Whether or not 6/24 was ever an option. Although 6/24 was NOTAM'd closed until further notice it is being claimed that aircraft were being landed on it less than 15 minutes after the crash.

So when was 6/24 reopened and when was the decision to reopen made?

Were the crew of 1354 made aware of 6/24's availability albeit after a short delay and a few extra track miles? I appreciate that if your preferred runway is NOTAM'd 'CLSD UNTIL UFN' you plan for another approach but if it is onto an unfamiliar runway that puts you down in the wrong part of the airport surely at some point in the sector the question would have been asked "Does anybody know when 6/24 is due to reopen?"

guess what we all don't know yet is whether the airplane had levelled off, then drifted below the appropriate altitude for that segment of the approach, (unlikely since the autopilot was engaged) or the aircraft was on a high rate of descent and continued below acceptable altitudes in an attempt to regain profile..(likely given the "sink rate" callout") wait and see what the DFDR reveals

Ahhh now i know why at some airports,there is a note that says,for those pilots: Do NOT mistake the highway lights for the approach lights.:E

Maybe 06/24 was reopened because there was a pile of smouldering wreckage and a few fire engines in the undershoot of 18. :zzz:

And as Airbubba raised a lot earlier in the thread, the small vertical error margin does make altimeter setting something to return to - the difference between 29.92 and BHM QNH 29.97 just happens to be 50ft low - "with wheels hanging 30ft below that".

Here, there are very few NPAs that have a true Visual Segment, where the visibility minimum is less than the distance to the runway. On any NPA, I would hazard a guess that if following a 3°-ish profile, you will always be able to see the threshold at the MDA if the vis is on the minimums or greater.

True, however at this point the crew would be operating visually on the PAPI and well below the MDA, and the altimeter value would be not a consideration.

I wonder if the crew was fighting sleep. Micronaps are not uncommon flying overnight.

The FAA as well as EASA need to establish and approve GPS/LPV approaches at all airports in lieu on the traditional N/P/As.

It will help to keep pilots out of the dirt a mile short of the runway, with the advances in the glass cockpit for both GA and Transport Category Aircraft. TAWS technology could be improved too.

All this talk about approach types etc is very interesting, however these folks appear to have been below airport elevation when striking trees and power lines....was somebody not monitoring inside??

ironbutt57:

Only at MDA, not below.

The VGSI provides 1 sloping 1 degree obstacle clearance surface, which begins about 1,000 feet south (in this case) of the runway threshold.

captjns:

This runway does not qualify for LPV, LNAV/VNAV, or ILS because the necessary qualifying visual segment areas are not sufficiently free of obstacles. This is true of many runway ends. There also has to be the correct type of survey, which many smaller airports are unwilling to pay for. (that is not the limitation at KBHM).

True most of the time. But, the FAA does have weak advisory standards for safety areas like these

Radio Altimeter???
 

Does this aircraft not have a radar altimeter? Every aircraft I ever flew in actual IFR conditions had a radar altimeter (some better than others). To my knowledge, no one has even mentioned it on this thread. I would think that once an approach is commenced the radar altimeter would be an integral part of the normal instrument scan.

Right that is true, but that applies to the obstacle cleareace afforded by the MDA *if* you are *at* the MDA.

That's a completely separate issue than the clearance afforded by the PAPI once you have descended below MDA on the PAPI.

A Squared,

The exchange between Aterpster and I was about the fact that the current Jepp plate lists the minimums to LOC Rwy 18 as NA at night. I was asking what could drive this requirement and he advised that the Jepp plate was inaccurate, the ball note making the approach NA if the VGSI are inop is accurate.

Well no, it really does not. You're confusing two different concepts. The obstacle clearance given by the PAPI has nothing to do with the obstacle clearance provided by being at MDA. And altimeter errors would have no effect on the clearance either way of the PAPI clearance.

The place where the airplane first started contacting trees was much lower than 50 feet below MDA and much lower than 50 feet below the PAPI so the approximately 50 ft altimeter error from not setting QNH on descent couldn't explain the accident.

Thanks for clarifying that Pipeliner,

- has this been confirmed? I do not see that 'altimeters' would possibly be 'in scan' at the time of the crash ('visual') but if this is true it is difficult to argue against screwing up the visual slope on the VGSIs. I assume they were 'ON'? I cannot also see how this fits with descriptions earlier from someone of 'skiing down the slope to the runway?

"FAA fails to pick up on vital clue that the aircraft were getting close to houses on the 18 approach"

Dear Mr Administrator

I'm writing to you to complain about the noise emanating from those homes underneath the approach to 18 at BHM. It's like they have parties all night every night. When my buddy and I fly the LOC 18, we try real hard to keep to sterile cockpit procedures but it's impossible with all that din. Can't you tell 'em to keep it down?

Regards

UPS Crew

---

Dear UPS crew

You're right, it is pretty loud, isn't it!? But it's OK, we're gonna get the airport to buy the houses and leave them empty. That should keep the noise down.

Regards

The Administrator

:)

Seriously, lots to learn all round from this one, I imagine.

Roulette,

As someone with a degree in surveying an mapping and who worked in that industry for years before I started flying for a living, I probably have a better understanding than most of the limitations of Google earth. I agree with your comments, especially that the accuracy varies widely in different locations. Certainly there are areas where even the 8 meters +/- accuracy in elevation would be optimistic. And again you're correct that there is no guaranteed level of accuracy anywhere, as here would be in a professionally prepared topographic product.

But given that the elevations at the airport match the published ones very well, it's probable the the errors are in the range of tens of feet, and not hundreds of feet. Which is useful for estimating things like: Did the crash happen above or below the airport elevation, or MDA.



Completely agree with that. I pointed out the PAPI obstacle clearance issue, merely as a point of interest. I never meant to suggest that it was a a factor in this accident, clearly they were far below the PAPI when they started hitting trees.

And it is worth noting that the image of the USGS topographic map posted by aterpster, which *is* a professional topographic product with a specified level of accuracy, shows elevations of around 840 MSL at the high point, and about 750 where the trees were first contacted.

boac....having previously operated there and reviewing the topography, the accident initial impact seems to be on an upslope, then sliding over the top to the top of the rise where the airport lies, also RE the monitoring, not sure of UPS' task sharing procedures, but generally speaking the pilot monitoring has the task of monitoring inside to assure the pilot flying has not fallen prey to some optical illusion and developed a wrong mental picture, resulting in significant deviation from the desired flight path...which is very possible during a night approach with scattered cloud layers...

BOAC, no, it absolutely has not been confirmed. Both Google Earthj *and* the USGS topographic map (See previous discussion) indicate elevations in the neighborhood of 750 ft MSL in the area where the flight first started hitting trees. From there the ground slopes up toward the airport.

There is nothing to suggest that they were below the airport elevation.

In Re Memoriam thirteen fifty-four
 

Having finished the morning portion of APCH acronym & abbreviation soup (mostly), I would like to proffer a question. The finely-honed details being discussed here (if my zero-hours legal mind is working at all) coalesce around the critical inquiry "How could this have happened?" The incredulousness seems rooted in the sense that this flight crew - while not open to criticisms such as those being leveled at the Asiana crew (and they too, and the people who were killed in that accident, should rest in peace) - flew way too low. Somewhere in the approach sector they deviated from a minimally safe altitude and the Swiss cheese holes lined up such that they didn't realize it and had no substantial reason to wonder. Quite different than the non-FTFA op on the Asiana flight deck, right?

The clue-seeking and thinking out loud here, the data scrutiny, the contextualizaion of approach sector design - to an administrative law and regulatory mindset, all speak to some subtle flaw in the approach corridor design. Subtle, and no less fatal.

So, here's my question. The UPS freightdogs perished in a moment both tragic and revelatory. Tragic because they were working stiffs who were just doing their gigs, to provide for their families, or to chase wine and women, or whatever their lives were about. In our system we honor the workaday ones, we don't fly couches or practice the law of cutting the lawn, we work. And revelatory because the approach corridor design process is revealed here to need mending. (In my discipline of the law this sometimes is known as "mend your hold".)

What does your fraternity of PIC and civil aeronautics do to honor their memory? Will a scholarship fund be established for their children or nieces or nephews or the kids at the local church temple mosque or yoga studio if they have none of their own? or at the Boy Scouts or Girl Scouts or 4-H or Explorers or the entity which the US ought to form combining all four of these groups? I began my career as a labor attorney and I don't even know if they were organized into a labor union! What can be done that will honor their memory, and at the same time help the taxpayers of this country realize that aviation safety doesn't just happen. It does not just happen by itself.

I'd gladly volunteer my legal services, saving to suitors the proverbial dollar (Sound as a Dollar), to set up a trust or scholarship. Or to press for legislative reform of how FAA updates approach corridors. I'm WillowRun Six-Three, good day.

- not making sense??

The trees are higher than the airport elevation on a ridge with an upslope. The ridge was higher than the airport elevation.

After clearing the crest of the ridge it slopes downward towards the airport.

BOAC, sorry, that was worded poorly. Yes, where the accident occurred, the ground is sloping up in the direction of the airport. Somewhere in the vicinity of where the wreckage came to rest, the hill crests, then the terrain slopes *down* toward the airport.

TDZE for RWY 18 is 644 feet, significantly lower than the area of the accident.

Does that clarify what I meant?

Yes thanks - do we have an initial impact elevation?

The terrain in the vicinity of where the airplane started hitting trees is between 750 and 800 ft MSL. Trying to define it any closer than that without actually being there and measuring thing would be futile.