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-   -   UPS cargo crash near Birmingham AL (https://www.pprune.org/tech-log/521370-ups-cargo-crash-near-birmingham-al.html)

Mudman 16th Aug 2013 14:57

I imagine that the reason for this crash, like most, will be a serious of incremental events that on their own would be benign but in combination prove fatal, "Swiss cheese" etc. I wonder if some kind of visual illusion might be one of those small events.
Visual Illusion Awareness


“Black hole” along the final approach flight path:

In case of approach over water or with an unlighted area on the approach path, the absence of visible ground features reduces the crew ability to perceive the aircraft lateral and vertical position relative to the intended flight path.

Uphill or downhill terrain before the runway threshold:

An uphill slope in the approach zone or a drop-off of terrain at the approach end of the runway creates an illusion of being too high (i.e., impression of a steep glide path, as shown on Figure 1), thus:
Possibly inducing a correction (increasing the rate of descent) that places the aircraft below the intended glide path; or,
Preventing the flight crew from detecting a too shallow flight path.

Ian W 16th Aug 2013 14:59

Fatigue and Performance
 
As people are talking of fatigue affecting performance and the associated regulations both in the US and EU, I thought I would refer to research that has been done using driving simulators. There is a lot of this research so just one link for now, it really merits its own thread perhaps in Tech Log.

from How do prolonged wakefulness and alcohol com... [Accid Anal Prev. 2001] - PubMed - NCBI


How do prolonged wakefulness and alcohol compare in the decrements they produce on a simulated driving task?
" Alcohol consumption produced changes in speed deviation and off-road occurrences of greater magnitude than the corresponding levels of prolonged wakefulness. While limited to situations in which there is no other traffic present, the findings suggest that impairments in simulated driving are evident even at relatively modest blood alcohol levels, and that wakefulness prolonged by as little as 3 h can produce decrements in the ability to maintain speed and road position as serious as those found at the legal limits of alcohol consumption."

aterpster 16th Aug 2013 15:29

Speed of sound:


I don't buy this.

You are not flying into a black hole if visibility is 10nm, you are below the scattered cloud and you can see eight bright red lights in front of you.

PAPIs either work or they don't. They are either on or off and they don't change angle once they are installed and certified. Even if I was Albert Einstein I would trust eight red lights over my calculations.

There is a very good reason why 'too low' is red and 'too high' is white.
PAPIs and VASIs have been found on occasion to be badly misaligned. In fact, for purposes of the visual segment (as defined in TERPs, Chapter 2) the FAA presumes such lights are unreliable for purposes of the visual segment of a NPA. (That presumption can be overcome on a case by case basis.) At an airport such as BHM I presume the FAA had verified these PAPIs as being correctly aligned. Otherwise, the two approaches would have categorically been NA at night because the visual segment is encumbered by penetrations of a 34:1 slope in the visual segment and, perhaps even a 20:1 slope (higher terrain a bit left of centerline with lots of trees and homes.

But, for all we know at this point the flight may have been cleared for a visual.

Capn Bloggs 16th Aug 2013 15:33

18 LOC approach according to Bloggs:

350ft per nm/3.28°.

21 7580
20 7230
19 6880
18 6530
17 6180
16 5830
15 5480
14 5130
13 4780
12 4430
11 4080
10 3730
9 3380
8 3030
7 2680
6 2330 (limit 2300)
5 1980
4 1630
3.3 1385 (MDA)
3 1280
2 930
1 580

Get on it, stay on it. End of story. Too hard to work out? Get the FAA to put it on your charts.

tubby linton 16th Aug 2013 15:34

Lonewolf the Jepp chart gives a descent rate of 813ft/min at 140kt ground speed. The FAF is at BASKN 6D, but only 4.7nm from threshold at 2300ft. The next check height is IMTOY 3.3D, 2nm from threshold at 1380ft.The Jepp shows the 3.28 descent angle starting at BASKN so you wouldn't need all the previous checkheights.
The runway threshold is at 1.3D IBXO, why didn't the installer get it to read zero at te threshold?
Jepp also shows a spot height just after IMTOY of 910ft amsl.
Jepp also has the following note:
Only authorized operators may use
VNAV DA(H) in lieu of MDA(H).

Were UPS approved for this?

ironbutt57 16th Aug 2013 15:45

possible as well their FPA calcs were wrong, sighting 4 reds and not wanting to "de-stabilize" (by climbing back up to the PAPI) they levelled off to re-establish the PAPI and encountered the trees and other in the process of doing this...the boxes looked pretty well cooked....hope they still have retrievable data...

Murexway 16th Aug 2013 16:10


If they were planning on doing a GPS approach then they might not have even tuned up the LOC with associated DME. The only distance reading would have been to the threshold from the FMC. This would have left them low instead of high.

I know it's a bit far fetched but..... stranger things have happened.
Well, this early in something seemingly inexplicable, almost nothing can be considered far-fetched - including sudden crew incapacitation. However, usual practice is (or should be) to use all available navaids. That would include, if possible, using VOR radials to cross check the IAF at COLIG, as well as a time hack at BASKN to time the segment from the FAF to the MAP. But I'm not sure why having an exact readout of the distance to the threshhold (LOC DME minus 1.3) would necessarily result in flying lower-than-published approach altitudes - for any of the RNY 18 approaches.

Capn Bloggs 16th Aug 2013 16:19


Only authorized operators may use VNAV DA(H) in lieu of MDA(H).
Tubby, can you post the Jepp chart?

It's odd that the FAA GPS chart makes no mention of an LNAV/VNAV minima ie a DA when Jeppesen does.


The FAF is at BASKN 6D, but only 4.7nm from threshold at 2300ft. The next check height is IMTOY 3.3D, 2nm from threshold at 1380ft.
Please clarify for me that those underlined altitudes are "not belows" as opposed to profile target/check altitudes?

Murexway 16th Aug 2013 16:21

8driver: Not disputing anything you say. The human factor, including the tendency to be able to "hack it" and be slow to realize the need for a missed approach, is very big in most incidents/accidents, especially on the back side of the clock.

Murexway 16th Aug 2013 16:49

Sorry, I admit I'm old school.... all this stuff about black holes and no lights until the REIL's seems irrelevant. I'm presuming that they were cleared for some sort of instrument approach. Black holes and lack of adequate visual references are why we have instrument approaches in the first place. Even if they were cleared for a visual, especially at night it would be unthinkable that they wouldn't have had some sort of instrument approach briefed and set up. Those are hard altitudes at specific DME's for a reason, and the PAPI's are there for the same reason: obstacles between you and the end of the runway - including terrain.

-JC- 16th Aug 2013 17:06


Just another airport in USA, nothing special really.....Been to Aspen, Telluride, etc and many abroad that would constitute a wording of SPECIAL
While Aspen and Telluride have obvious terrain challenges, the last 1.0nm of the published approaches into these airports is over flat terrain, actually in both the terrain is lower than the threshold. The last mile on the runway 18 approach into BHM seems unique in that the terrain rises to almost 200 feet above threshold elevation just over 1/2 mile from the end of the runway, directly on the runway centerline. The fact that it isn't a big jagged rock but an innocuous looking shallow upsloping hill makes it seem all that more insidious.

Show me a published IFR approach to a major airport that has terrain impacting the glidepath like that over the last mile to the runway ?

tubby linton 16th Aug 2013 17:27

The published altitudes are not below figures for their relavent dme positions. The gps rnav chart also has the same note about approved operators using vnav minima

Coagie 16th Aug 2013 18:00


Murexway, you're pretty hard on somebody suggesting a catastrophic incapacitation. We lost a Captain who had a heart attack rolling out in a DC-8 in Indy on 32 roughly 13 years ago. He started to drift off centerline and the F/O took control but couldn't stop it before they ran into the mud off the end. The engineer had to pry the guys hand off the thrust reversers. No movie, it can happen and it takes awhile to recognize incapacitation. Does your airline train for it? Mine does, although truth be told we always know its coming in training. It can be very ugly (ala JetBlue), it may come on slowly, or it may be very fast

Passenger 389- Nobody is being insulting saying fatigue might be a factor. It isn't like the guy said they planned to have a sleep and wake up on short final. Unless you've been there, done it, and got the T-shirt with back of the clock flying you don't know what it feels like.
Thanks 8driver for pointing the not so far fetched issue of sudden incapacitation and the important issue of fatigue. Having dealt with all sorts of rotating shifts, alerts, etc, I know how tough it is to switch from day to night and night to day, and still know up from down, left from right, not to mention just staying awake and concentrating during critical times. I'm guilty of getting Murexway and Passenger 389 to think, and it ended up hurting their feelings, and they responded impulsively, or they momentarily forget, that pilots have the same physiology as mortals, and are subject to falling asleep, or being incapacitated by illness, through no intent or fault of their own. I'm not used to taking people's feelings into account, when I'm trying to solve a problem, that is not of the heart. I apologize to him and her, for hurting their feelings. It was not my intent.

JimField 16th Aug 2013 18:04

Did you bother to read Sooeet's article for Asiana 214?
 

There's no point in such work (other than for ego) because it can't possibly describe what occurred without the flight data from the recorders. Anything else is just a cartoon.
Sooeet nailed the Asiana 214 final approach profile days before the NTSB released several data points of FDR data for the last 3 nm of the approach. What makes you think that a similar analysis for UPS 1354 is any less accurate? Aren't you jumping to conclusions before looking at the data?

What Happened to Asiana Airlines Flight 214 - Analysis by Sooeet.com

Murexway 16th Aug 2013 18:18

Nope, not offended or "hurt" at all. Since I've flown many all-night trip pairings, I'm not discounting physiology and didn't mean to sound immune to it. :)

Airbubba 16th Aug 2013 18:22


In the lower left hand corner, FAF to MAP times are 1:53 at 150 kts GS, and 1:34 at 180 kts GS. This would tell me, as a pilot, that if I were flying a CAT C or D aircraft on this approach, I should be configured, and on approach speed well before the FAF, and have my estimated ROD figured out before I hit the FAF. If I had a tool in the cockpit that allowed me to create a 3.28 glide slope that keeps me above min altitudes before FAF, all the better.

It looks as though the approach need ~700 fpm ROD if GS is 180, ~580-600 FPM ROD if GS is 150.

I'm just a driver, not a rocket scientist but you might want to re-check those numbers for a 3.28 degree glide path.

Airbubba: The approach plate I am looking at is dated 25 July 2012, from SE-4, AL-50(FAA). Glide slope noted as 3.28 degrees. The math went like this. (It may or may not reflect said glide slope. I don't have my old GS table at hand ...)

Hmm, you have a point, my calc was to MAP, not touchdown.

I'll try a different method.

If I start at the IAF at 3500 feet (as shown) and arrive at threshold (644 feet), I lose 2856 feet over a distance of 12.8 nautical miles.
150 kts GS gives me 2.5 nm per minute (5.12 minutes) 558 FPM.
180 kts GS gives me 3 nm per minute (4.27 minutes) =670 FPM. (Not far from ~700 fpm)

Granted, one should cross the threshold higher than 0 feet AGL. Call the total delta in alt -2800 feet and decrease ROD slightly to hit the box.
From discussions on a PPRuNe sister forum, UPS pilots use Jepps.

I was thinking the crew would probably shoot the RNAV (GPS) RWY 18 approach but they certainly were legal to do the LOC Rwy 18 (don't know why it's RWY on one plate and Rwy on the other).

Anyway, take look at the LOC Rwy 18, chart 11-2 dated 17 AUG 12.

There is a small rate of descent table on the left side. For 140 knots groundspeed, the rate is 803 fpm, for 160 knots, 929 fpm. This seems about right from my experience, your ROD numbers appear to me to be too low for the groundspeed.


You are not flying into a black hole if visibility is 10nm, you are below the scattered cloud and you can see eight bright red lights in front of you.

PAPIs either work or they don't. They are either on or off and they don't change angle once they are installed and certified. Even if I was Albert Einstein I would trust eight red lights over my calculations.
The BHM 10-9A chart has the notation PAPI-L (angle 3.2°), as HDRW points out, there would only be four red lights in this case.

It has been claimed by ALPA in defense of the pilots in the 2002 FedEx TLH crash that moisture can affect the operation of PAPI's:


ALPA is disappointed that the Board did not fully explore the possibility that moisture condensation on the visual approach aid (Precision Approach Path Indicator, or PAPI) gave the crew a false indication. The FAA was aware of this problem as far back as 1983.
ALPA Reaction to NTSB Findings in FedEx Accident. - Free Online Library

M609 16th Aug 2013 18:31


Show me a published IFR approach to a major airport that has terrain impacting the glidepath like that over the last mile to the runway ?

Vel, perhaps not major....but it does welcome A300 and larger aircraft on a regular basis.

Bardufoss/ENDU

Murexway 16th Aug 2013 18:56

Not trying to hang the crew, but unlesss there's evidence of mechanical failure or crew fatigue/impairment, the possiblility does exist of an intentionally flatter than 3.28 degree final approach (with a lower than 48' TCH) in order to plant it on the numbers of a 7,000' runway.

BOAC 16th Aug 2013 18:58


Originally Posted by -JC-
The last mile on the runway 18 approach into BHM seems unique in that the terrain rises to almost 200 feet above threshold elevation just over 1/2 mile from the end of the runway,

- hmm. That would make a 3.28 slope VERY interesting. You sure about that?

tubby linton 16th Aug 2013 19:07

On the 10-9 airport chart there is a symbol almost on the centreline forRW18 for a lit obstacle at 819 ft amsl, The obstacle is within 2000ft of the runway threshold and it would be 175 feet above it. Slightly to the left of the centreline some terrain is depicted at 757ft amsl.


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