And if you want to put in the quoted poster's name, you put it in the opening quote code like this:

[quote_=Bloggs]quoted text in here[/quote].

Don't use the red underscore before the = sign, I had to otherwise my example quote would become a real quote like this!

Thanks Cyrano, that's even better than my method.

MM43
 

Thanks very much. Just curious.

Regards.

Someone was asking earlier about the Alert vs Sink Rate envelope at differing altitudes.

This is from Honeywell but I'm sure other brands are available! ;-)

http://i1280.photobucket.com/albums/...pse3e80150.jpg

G/S angle?
 

@MM43

The FAA LOC18 approach plate that aterpster showed earlier had TCH of 48' and G/S angle of 3.28. Did you have a different plate, or why did you use 3.20 on your excellent profile graphic?

WR,

Before a report goes final it is sent as a draft to all the parties. They have an opportunity to comment by submitting Submissions. The Board (or Staff) may ignore the comments but the Submissions are published as part of the docket when the final report is released. You have to download the entire docket to get them so if you just read the final report you may or may not see the fruits of the Submissions.

I don't believe it looks at VS. Radio altimeter sees acft closing on the terrain. Acft could be going down or terrain could be rising.
It's just a dumb box.

I don't think the EGWPS is a dumb box, I believe it gets vertical speed information from the IRU's on the A306.

The VDA is 3.28.

The PAPI angle is 3.2.

http://i202.photobucket.com/albums/a...ps47064af9.png

You are correct: V/S vs Rad Alt Logic
 

There is a published formula that describes the "SINK RATE" alert logic which is a function of V/S and Radio Altitude. UPS would have had a VS higher than -1000 FPM (perhaps more like -1200) for the alert to sound.

mm43's chart - visuals - flying testbed (huh?)
 

Two (2) questions, somewhat connected.

Charts, Plates, and angles/distances of REILs, PAPIs & etc. Readers' attention is respectfully requested to be directed to mm43's chart or graph, depicted in post no. 661, above. It depicts a range of approach information, altitudes and ground elevations especially, and related data points derived therefrom. QUESTION is, do there exist depictions of visual cues at distances along a given approach to a given runway? Let me attempt, at least, to illustrate the underlying predicate for this query using the current quasi-investigatory thread. A goodly number of members have analyzed and/or commented upon, or at least provided input of just an informational variety about, the ability of the 1354 pilots to see the PAPIs, and related stuff about the visual set on approach. Stuff like was there a beacon on a hill at some point, what could the CT guy see and whether that matters, and especially the possibly emerging consensus that the approach was flown so low that the visuals blocked the pilots from knowing they were too low -- no, let me make that harsher - the visuals worked in a very nice evil and ultimately fatal conspiracy to lock the pilots into a terribly wrong sense of complacency. So, are there Jepps of the visual variety? I'm asking this even though I am willing to gamble that the Flight Safety simulator programs depict approaches (duh) but how close or or far are those depictions from what the Mark 1 eyeball sees out in front of the aircraft? In terms of very specific alignments of PAPI at given combinations of altitude and distance, and terrain or obstructions, and so on.

Question two. Has anyone tried to build (I know, you'd need funding first, I get that) a testbed aircraft that would shoot approaches which experience has shown to be troublesome, for the purpose of finding out not just what the next approach plate will depict, but a truly safe approach? Let's say a souped-up ex-Pan Am DC-10-30, loaded with instrumentation, ramped up powerplants, and pilots holding zero bs tolerance for other than precision in measurement and analysis. I note this even though I once tried to buy exactly that type of Airplane using nothing but my own name to pay for it...no of course I had not figured the cost of redoing the livery so that it would read, in bright Maize letters outlined in a Blue border with a narrow white space in between THE UNIVERSITY OF MICHIGAN. (Against a Gleeming white base coat all the way down to about 10 degrees port & starboard up from the nose gear doors.) Anyway, does somebody already operate such a testbed for getting better parameters for FAA to improve approach designs?
Thanks for reading. It is a privilege and an honor to be able to communicate with all the fine pilots and others on this board who actually know about this stuff - and I am loath to overstate my welcome, and hence welcome all comments and criticisms.
I'm WillowRun 6-3, la-covet (Hebrew for, 'in honor of') the Willow Run Laboratories of the University of Michigan. Good Day.

to mm43 RE diagram
 

Nice work - can you do something for us? Figure out the sight lines to the bridge on the extended centerline over which I-59 passes - it's just south of the threshold for 36. Here's a Googly from it..

http://maps.google.com/maps?hl=en&ll...359.08,,2,4.34

The FAA has 33 planes and about 200 pilots and technicians in their Flight Inspections Operations Group. Their full time job is to fly approaches and airways and make sure they are up to standards. No DC-10s, just King Airs and biz jets. Every ILS in the National Airspace System is flown every 270 days and every non precision approach is flown about half as often.

@ kenneth house

I got confused when I initially looked at the AL-50 plate, and Tubby Linton drew my attention to the differing G/S angles for RWY 18.

Here is a link to the up-to-date plate info for AL #:50 that was originally posted by aterpster.

@ deSitter

I'll have a look at the clearances for RWY 36 over the I-59 when I get some time in the next day or so.

WillowRun 6-3:

NASA has a DC-8 airborne science laboratory that could be configured to do just that. Approach some science types, maybe through Univ of North Dakota National Suborbital Education and Research Center (NSERC). You never know what might become of it.

DC-8 | NASA Airborne Science Program

The airplane is presently flying the SEAC4RS program out of Houston (KEFD) until Oct 1, in case you're in the area.

Sure it's a dumb box. It can't think on it's own. :hmm:

Oz, et al, even if not intelligent, EGPWS has excellent logic and when heeded has immense capability to save lives.

If the reported EGPWS alert was ‘Sink Rate’ (which I am unable to confirm) then this should have been generated by mode 1 which uses aircraft vertical speed vs Rad Alt. The VS required would appear to be very high for the scenarios surmised so far.

However, if the alert was ‘Don’t Sink’ then this might have been generated by mode 3, but the description of this suggests a dependency on gear and flap switching to determine a difference between after take-off and go around. Although the latter function might apply in this accident, the reported gear and flap position suggests not.

Many accidents have happened in the past when undesired high rates of descent developed when both crewmembers were involved in attaining visual contact/references with the runway/lights/PAPI etc...etc...and nobody was minding the store.(monitoring inside).

what about an incorrect pressure setting? Just a thought, apologies if it has already been mentioned.

What was wrong with reading (or searching) the thread before posting?

Then you would know whether or not it had been discussed (it has).

DaveReidUK

Thank you for taking the time to point that out, as I said it was just a thought. Having taken your advice and reviewed the thread in a little more detail I can see its been mentioned. May I also say your post of a picture (315) in response to the landing gear is equally as useless.

"Many accidents have happened in the past when undesired high rates of descent developed when both crewmembers were involved in attaining visual contact/references with the runway/lights/PAPI etc...etc...and nobody was minding the store.(monitoring inside)."

Is there an effective way to change this behavior? Improved procedures and training?

I do not understand why there is a discussion about R/A EGPWS, given an obvious obstacle it would have most likely been inhibited by the flight crew.

Given that proficiency in instrument flying and approaches are checked at every PC and NPA's are normally covered in PTs, it is strange that incidents like these are still happening in the developed world. Maybe they are so good at visual flying that complacency set in, when instrument approaches are deemed to be a walk in the park!

However I think the pilots had more instrument approaches under their belts than visual approaches and it is baffling how a localiser approach could be so badly stuffed up? Maybe some electronic interference from an active system in their freight or l@ser light interference from the ground? I believe the pilots were highly experienced and very competent, so pilot error must be a very very remote possibility!

As aircraft accident statistics show competency and experience has nothing to do with it. Take some most egregious cases of pilot error (in commercial flying) in the last say 40 years and they were all caused by experienced and well trained crews.
Not sure what it is supposed to mean, approaches in IMC weather are flown in minority of cases, say 10-20% (will depend on geographical area) so visual approaches tend to dominate in pilot's logbook.

@olasek

I think you got trolled:)

mm43, I'm more interested in the sight angle of that bridge from UPS just before the troubles. I have a crazy idea that they may have mistook stalled morning rush hour traffic on this bridge - a mix of red and white lights - for the PAPI. The highway stands at a rather acute angle to the runway so this is possible.

I don't know, but I think that inhibiting the EGPWS only inhibits the terrain database function; the basic functions such as the Sink Rate call would still be active.

I think you can't understand English. His opinion post reads OK to me.

Using Google earth, I compute the following:
highway altitude:+/- 640ft
Mrs Benson pine tree altitude: +/-830ft
distance from highway to pine tree: +/-14200ft

That makes for an angle of less than one degree (0.77°).

The highway altitude is somewhat below runway southern threshold (660).

If they could see the highway, it must have seemed awfully high on their windshield...

@deSitter
 

I go the other way about this arrival.

I think they may have been too low to even see the PAPI or REIL's.

The runway in sight call out was what the PNF saw of the remaining runway lights.

If they mistook lights on I-59 for PAPI's, they (the PAPI's) would have been at the wrong end of the string of runway lights.

If Mrs. Benson's trees are 921' MSL, they were already more than 279' below minimums, possibly before IMTOY.

Also, it's been a long time since I have driven through Birmingham in the morning, is there that much bumper to bumper traffic there at 5 AM?

I live ten miles from the accident site. I frequently drive in to the airport at o'dark thirty. I don't believe there was much traffic on the I-20/59 interstates at that hour. Not saying it couldn't happen, but...

I'm more interested in my brother-in-law's account: He drove to work at an auto shop about 5 miles from the accident, about a half-hour later (5:30). He says the ditches were filling up with fog....

Significative information! Thanks

I'm surprised at the suggestion that pilots routinely inhibit the EGPWS terrain floor function if they think there might be ''obstacles''. I would only do this if I knew that the landing runway was not in the database; after all, the whole point of it is to warn that you're following an unsafe path relative to terrain/obstacles. If you're close enough to trigger a caution or warning, then you need to do something positive quickly!

As they were on an NPA, my reading of FAR 91.175 (being an EU-OPS guy, although it's very similar) says the visual references required are fairly broad and don't mandate slope guidance. Just the approach lighting would be fine until <100' above the TDZ.

Given the falling ground under the approach path and the shorter runway, the expected visual illusion is that of being too low. This might have been countered by uncertainty from the 'black hole effect'. Puzzling. It would be very interesting to synthesise the view out of the window at various stages during the approach when accurate flight data becomes available...

Anyone like to guess at the power setting at impact based on post #315?

...Idle...

Yeah... :}

Fullwings this runway had no approach lighting.

Yes, you're right, I've just looked at the plate. Nearly diverted there a couple of months ago. Makes the VGSI all the more important.

Has anyone here landed on this runway at night? Is there any sort of ''texture'' to the lead-in: lights, strobes, lit areas, etc. or is depth perception difficult?

An approach to this runway was described many pages back as being a black hole. There are strobes on the runway ends and the runway lights are only medium intensity. Do you have a copy of the Navtech(aerad) chart for this place?Does it mention anything about the approach not being available at night?

Yes...

It says: ''Note: When VGSI inop, procedure NA at night. Circling NA'' and the note was revised Dec 2012.

It also gives a 3.3deg slope on the profile chart but a 3.2deg one on the DME vs. ALT box; probably rounding either way.

There are CAT D minima of 1200' and 1 & 5/8sm for the LOC+IMTOY and 1380' and 2sm for just the LOC. Out of interest, the RNAV (GPS) 18 has 1200' and 1 & 3/4sm.