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-   -   Turkish MD-83 Crash (https://www.pprune.org/rumours-news/302525-turkish-md-83-crash.html)

Machaca 12th Dec 2007 02:21

Path to Türbetepe?
 
In the first few days following the accident, rumors were rampant the pilots short-cut before CARDAK.

Next we heard that they were cleared direct IPT.

Now we are told flight 4203 flew YAA KFK EKSEN1C IPT.

http://img139.imageshack.us/img139/3...s01bls3.th.jpg


Hmmmm. 18 minute racetrack, lawsuit filed, empty CVR, incomplete FDR data. Any chance the logbook with any MEL's will apppear?


-=MachacA=-

PBL 12th Dec 2007 05:28

Machaca,

thanks for all the info.

There are a lot of things wrong with the images used to illustrate the supposed track. For example, they look as though they come from some sort of official publication, but the runway is oriented at about 40° to "upright" and the inbound course at about 60°. Whereas the runway is designated 05, which means it is oriented somewhere nearer 50° magnetic and the inbound course is 043° magnetic. The magnetic variance is 3.2°E, so the difference between magnetic and true does not account for this discrepancy.

Interestingly, the outbound course of the aircraft is shown on these images as more or less aligned with the Rwy. Which it wasn't, if the track data are to be believed.

If he wasn't on radar, I wonder how someone managed to reconstruct the track? And if he was on radar, how come nobody said anything to him as he proceeded outbound 30° off track into mountainous country? And if this is from the FDR, I guess all that "unusable" data somehow became usable.

The track doesn't cohere with md80Forum's observation that he reported overhead VOR at 23.18Z and inbound at 23.36Z (post of [email protected]), according to MaxBlow's transcription of the Hurriyet report on 30.11@10:54PPRuNe. (Emphasised also by clearedtocross on 07.12q12:39PPRuNe. Note: I give PPRuNe time, because, despite claims, PPRuNe does not time posts at UTC. Neither does it maintain a constant offset to UTC: PPRuNe posting times changed by an hour when European daylight savings ended.) It would mean he took 18 minutes to traverse what looks to be about 24 nm, which does not compute given there was only a light wind.

Lomapaseo asked what critical data one expected to get answered only from the black box. I would have thought that the box's recorded heading, altitude and airspeed would be crucial info, whether it corresponds to real heading and altitude or not (nav equipment failure, for example, as suggested by clearedtocross on [email protected]). Or is there some reason to expect these not to have been recorded?

Speaking of the boxes, MaxBlow was reporting on the day of the crash that they were said to have been recovered. I wonder why it took almost two weeks to figure out if the data were usable? Flightglobal (David Kaminski-Morrow) was reporting on 05.12 that the German BFU was expected to analyse the data (link from cwatters [email protected]); it has still taken a week since then.

hetfield and Cyclone733 asked about radar and have not been answered. I don't know for sure yet. Given that the airport has virtually no facilities (no fuel, for example, and no jet starting unit) I would be surprised if it had radar. I doubt that en-route radar would be much help at approach elevations some 1000 ft above terrain: the procedure turn on the approach is at 7000 ft and there is 6000+ ft terrain some 5 nm left of the approach path and also at about double that distance right.

I don't see what relevance the list of nav problems apparently associated with decommissioning of ONS might have to this crash yet (listed by MachacA just now). This was a simple VOR-DME procedure, and they were supposed to have been following a VOR radial outbound at 223°. It is hard to see how one could be 30° off that unless one completely misread the chart (a mistake which has little to do with what kit is on board).

During the discussion about CFIT versus stall-in, there were various "if" scenarios involving hitting with one wing first, on rising terrain, and so on. Do we now agree from the pictures that the aircraft hit flat on the roughly flat top of a hill; that there appear to be gear traces in the impact point; and that the impact trace is unusually short for incidence parameters of (say) 140 kt at 3 degrees-ish?

I also noticed that a lot of posts have disappeared, expecially all those by BoeingMEL. I wonder if that is embarrassment or censure?

PBL

maxrpm 12th Dec 2007 08:14

PBL: "This was a simple VOR-DME procedure, and they were supposed to have been following a VOR radial outbound at 223°. It is hard to see how one could be 30° off that unless one completely misread the chart (a mistake which has little to do with what kit is on board)."


I seems that they were cleared direct to the VOR from the north to start the VOR/DME from there. If that is the case they were not supposed to fly 223° outbound as they had to enter the racetrack yet.

Inbound from the north - a parallel or a teardrop entry would have been the appropriate choice.

A teardrop entry would have called for 193° heading (30° to the left from 223°) follwed by a right turn to 43° to establish on the 223 Radial inbound.

I do not know if the information about their actual heading of 253° outbound can be confirmed but if this can be confirmed it looks like an error in the direction of the turn.

Instead of 30° to the left in order to enter the racetrack they turned 30° to the right giving them 253° heading.

The rest of the picture would fit. In 12DME they turn right in order to establish inbound on the 223Radial. But from their actual position this is impossible.
223 Radial is not coming in so they extend their turn to the north still waiting to get established on radial 223.


If this hypotheses has some ground than they must have realeased after a few minutes that something was wrong. Seeing the airport lights 10 miles to their right they might well have decided to stop the confusion and just turn in visually on that clear but dark night.

They never reported established inbound on the VOR/DME appr. instead they reported field in sight. Not an uncommon or suspecious call but fitting the picture.

Still there is no explanation for the 18min timegap.

Earl 12th Dec 2007 08:55

http://www.turkishdailynews.com.tr/a...?enewsid=91065
ISTANBUL - Associated Press

An initial investigation shows that pilot error caused the plane crash that killed all 57 people on board last month, local media reported yesterday.

Authorities say they believe the pilot became disoriented while preparing to land at Isparta in southwest Turkey, but further investigation was needed, CNN Türk television and the daily Zaman newspaper reported.

"The primary data suggests the pilot lost spatial consciousness," Zaman quoted an unidentified civil aviation official as saying.

The office of Ali Ariduru, head of Turkey's Civil Aviation Authority, said he was not immediately available to comment on the reports. Atlasjet, the operator of the flight, declined to comment.

The Atlasjet MD-83 was flying from Istanbul to Isparta when it crashed early on the morning of Nov. 30, killing 50 passengers and seven crew members. Authorities have said the plane was off its flight path when it crashed. The wreckage was found 11 kilometers from the airport, on a mountain around 1,500 meters high.

Zaman and another newspaper, Yeni Şafak, said investigations showed the cockpit voice recorder was not recording before the crash, and the flight data recorder produced little usable data. However, CNN Türk said the recorders were working properly.

Officials had said there was no indication of sabotage in the disaster, which occurred in good weather minutes before the plane was scheduled to land.

Atlasjet, a private airline established in 2001, operates regular flights inside Turkey and chartered flights to Europe and other foreign destinations.

Earl 12th Dec 2007 08:59

Conflicting reports from the media, CNN Turk is quoted as saying the recorders were working properly.

PBL 12th Dec 2007 10:08

maxrpm,

I won't disagree with anything you're saying, but I would like to point out two possibly conflicting pieces of information.

1. I acknowledge the intervention from SeattlePilot who reported his good friend working the flight, and then finding out that Ankara gave them direct IPT, which would have them coming in from the north.

But then MachacA just suggested "we were told" he was on the EKSEN 1C arrival, but printed a map showing a path from CARDAK (CRD), which is the PELIL 1C arrival. These are reciprocals of each other: EKSIN comes in to IPT on the 078° radial, on a heading of 258° from EKSEN, and PELIL comes in on the IPT 260° radial, on a heading of 080° from CRD. So on PELIL he would be making a direct entry.

2. You say

Originally Posted by maxrpm
They never reported established inbound on the VOR/DME appr. instead they reported field in sight

Looking at the ATC transcript from Hurriyet, reported by MaxBlow on 30.11.2007@10:54PP, he was asked to report inbound by ATC and reported "established inbound" at 23:36Z. We don't know yet which approach he was on, the VOR DME, or the VOR/NDB (the difference I see is whether you measure the turn inbound by DME or by time).

PBL

Machaca 12th Dec 2007 12:35

Teardrop 30 degree Error
 
maxrpm,

I believe you nailed it. Tired crew makes simple error. Comports with Ockham's razor.


-=MachacA=-

Machaca 12th Dec 2007 12:45

Truthiness and Flight Paths
 
I've more trust in SeattlePilot's hearsay re direct IPT than the "officials" at some press conference aired by CNN Turk yesterday:

http://www.cnnturk.com/VIDEO/index.asp?vid=2679

What a circus! Those diagrams!!! What black boxes are those -- I thought they were in a lab in Germany?!


-=MachacA=-

lomapaseo 12th Dec 2007 12:52


I believe you nailed it. Tired crew makes simple error. Comports with Ockham's razor.


-=MachacA=-
If the "tired crew makes simple error" is simple and probably common, what is the backup barrier that should have caught this and prevented the rest of the combinations that resulted in this accident:confused:

I mean that we can expect more tired crews and more simple errors but we should not be accepting this as the only cause of the accident.

Where's the intervention to this?

Machaca 12th Dec 2007 13:22


what is the backup barrier that should have caught this and prevented the rest of the combinations
All the standard answers apply. Training, CRM, equipment upgrades (EGPWS), double checking your sums, duty time/rest, communication...


-=MachacA=-

lomapaseo 12th Dec 2007 15:31


All the standard answers apply. Training, CRM, equipment upgrades (EGPWS), double checking your sums, duty time/rest, communication...

I don't agree. Most of the above are precursors to the crew error not additional barriers to an accident following common crew errors.

pls8xx 12th Dec 2007 15:42

Flight Path
 
While I am still struggling to pinpoint the crash site, there is one thing I am rather certain about ... the heading at time of impact was generally NE, parallel to the runway.

One of the photos made on the morning of Nov. 30 had the camera pointed parallel with the crash scene. In it one can see shadows near 90 degrees to the camera angle. The shadows are 2 to 2.5 times the height of objects.

Using the solar calculator at .... www.srrb.noaa.gov/highlights/sunrise/azel.html


By trial and error I adjust input to get a solar elevation that will yield shadows of the length seen in the photo. This occurs about 9:45 AM. The azimuth of the sun at that time was about 149 degrees.

http://i9.photobucket.com/albums/a93/pls8xx/solar.jpg

Turning back to the photo, one can see a high point along the horizon in the upper left that is near alignment with the crash scene. Google shows a peak about 25 mi at around az 54 degrees from the general area of the crash.

http://i9.photobucket.com/albums/a93...g?t=1197476726

From info on radio communications, gear down comments, an altitude less than 7000, and the flight path derived from the above analysis, I conclude that it's likely the crew thought they were on final approach.

PBL 12th Dec 2007 18:17

Now that, pls8xx, is class! Very nice.

PBL

Earl 12th Dec 2007 21:19

Quote:lomapaseo
Oh, and just what critical question did you expect to get answered only from the black box ?

Earl: CVR should have added quite a bit of information as to what happened.
Approach briefing to begin with, who was the PF,PNF, EGPWS warnings and what actions were taken, CRM, standard call outs, many things that would have helped this investigation, if true that they were disoriented this would be more than apparent on the recording.
This was an important piece of the investigation.
DFDR would have backed up much of this info.
Really surprising question here!
Care to expand on this comment?
Or just more Media!

Green Guard 12th Dec 2007 22:52


Hmmmm. 18 minute racetrack, lawsuit filed, empty CVR, incomplete FDR data. Any chance the logbook with any MEL's will apppear?
You must be kidding !!
Just think why was CVR "empty" and FDR "incomplete"" !! :{

Machaca 13th Dec 2007 02:59

Nice work pls8xx!

Using both on-site photos looking out and many photos of scenery in the surrounding locales, I used roads, terrain, vegetation, landmarks, reports, etc. to deduce Türbetepe's location and the point of impact to be:

LAT 37.873 -- LON 30.200

http://img89.imageshack.us/img89/916...ge01cy6.th.jpg

Here's a view looking West over IPT to Türbetepe:

http://img89.imageshack.us/img89/937...epe1sl5.th.jpg

Here's a view looking South to Türbetepe from above the town of Aydoğmuş:

http://img443.imageshack.us/img443/9...700emk3.th.jpg

Here's a flyover view of the area -- crash site area is obscured by the inboard canoe!

http://img150.imageshack.us/img150/5...147bai8.th.jpg

From atop Türbetepe you can easily look about in Google Earth and match up the views seen in many of the photos taken at the crash site.


-=MachacA=-

PBL 13th Dec 2007 07:38


Originally Posted by Earl
Or just more Media!

No earl, he is not, as you could check for yourself.

Let me take this opportunity to say that I find these sorts of prejudiced comments unnecessary. Much of the information any of us have about this accident has been gleaned through the hard work of journalists. I prefer to appreciate this necessary work, not to demean it.

PBL

MaxBlow 13th Dec 2007 08:17

more charts
 
www.airporthaber.com/hb/detay.php?id=22559

here're more pictures/charts showing the track flown by the aircraft.
Maybe someone can translate the text.

hetfield 13th Dec 2007 08:35

@Max

What does the 2nd picture say about DFDR (red)?

MaxBlow 13th Dec 2007 09:24

DFDR
 
I'm not 100% sure but understand the following:
'Once analysed the DFDR will explain why the aircraft was flying this track'

learsimmer 13th Dec 2007 12:29

If anyone reading this is familiar with flying in the next valley parallel to and to the West of Isparta (that's the valley that contains Cardak airfield and the town of Basmakci) could they say at what minimum altitudes an aircraft flying overhead, say Basmakci, could be expected to receive useable radio transmissions from Isparta VOR (IPT 117.50) or Isparta NDB (IPT 349)?

Nick

hetfield 13th Dec 2007 16:40

@post 264 by Max

What does this picture say?

http://www.airporthaber.com/hb/pic.php?id=16838




- is it a guess by journalists?
- is it a radar plot?
- if so, did radar coverage stop after the aeroplane entered mountaneous terrain or after the crash?

Thx

PBL 13th Dec 2007 17:29

The pictures from airporthaber.com are not necessarily that helpful. The first one shows the approach with a direct entry into holding from the northwest. The second shows an approximation to the actual track, with the annotation that the DFDR will give the exact data (hetfield: that is what it says).

They are the only representation I have seen that suggest the aircraft approaching IPT from the northwest. The EKSIN 1C arrival from UA-18 from the Afyon VOR comes in to IPT from the East, from intersection EKSIN on a heading of 258° on the 078° radial of IPT; the PELIL 1C arrival from CARDAK (CRD) on a heading of 080° on the CARDAK radial 080 and then the 260 radial of IPT from PELIL. There is no arrival from the northwest. If they had flow Afyon direct Isparta, as suggested by SeattlePilot, then they would have come in from the north heading about 184°, because that is where Afyon is. The magnetic variation at IPT is 3.2°E. One can see all that from the en-route chart snippet uploaded by MachacA, and the arrival and approach plates to which the links have been given in this forum.

The best info comes from the article from Hurriyet on 12 December, included by Machaca. It doesn't say where the aircraft came from, but it does say that they came in at 8,000 ft. After passing the VOR they followed a track of 253° until 12 nm out, then turned right. They also didn't stop at the inbound heading of 043°, but went a further 50° around to 093°. Then they hit Türbutepe at about the 1,500 m mark. There was a GPWS warning. At the "pull up" warning, they did indeed pull up and put in power, but the power application pitched the aircraft up and the tail struck.

Hurriyet says that this information comes from preliminary analysis of the FDR and CVR, and that these have been sent to Germany for further analysis.

So it looks as if it was CFIT, as many have thought.

The question here is: why 253°? The following was suggested to me in PM (by a participant who is a little fed up with certain participants chewing others out for not being professional pilots). This is close enough to the 258° heading required for the EKSIN 1C arrival. Perhaps they had loaded the heading for the EKSIN 1C arrival at or before Afyon, and then after they were cleared direct switched to that instrument upon station passage at IPT, without remembering or checking that this was the arrival heading they had loaded and not the outbound heading for the VOR/DME 05 approach. This is pure speculation, though.

Thanks very much to my student Tülay Inci who translated the text for me today in conversation.

PBL

zeynep737 13th Dec 2007 18:20

This accident showed us that the Turkish government is still inadequate about solving these kind of disasters..ı m a Turkish citizen and ı can watch what our authorized people r doing here..this is the 3. plane crash in Turkey since 1998,and in all accidents the reason of the crashes were explained on the day of event but in this case noone can explain and ı still cant find out why?ı m not an aviation authority but its not just a pilot fault,there r missing parts..first they said the CVR was empty and now they say CVR is being solved(?)There were 6 Turkish nuclear physicians aboard from Boğaziçi University and Doğuş University-going to Isparta to a symposium-they were working on a material named torium,when these element is used in Turkey in nuclear stations than our country will never need petrol oil,and while our external debt is 450 billion $,with the usage of this element our country would have 70 trillion $ source...With this invent our country would be one of the most biggest energy source but somehow it was stopped(!) the cause of this accident cant be just because of pilot fault...

hetfield 13th Dec 2007 18:26


the cause of this accident cant be just because of pilot fault...
I'm afraid, it can...

zeynep737 13th Dec 2007 18:37

ı hope this accident can be explained as soon as possible..it was pilots first flight to Isparta which means that they didnt know the area(thats why therer r landing charts but ı guess the crew trusted themselves a lot..)

LuckyStrike 13th Dec 2007 22:01

- It is a clear night
- "Runway in sight" reported

These are the established facts that I have drawn out from various posts here...

Now if that's the case how would they end up in those mountains as there is no limitation for the pilots to see the runway after assuming their crash heading? They would be following the runway as they were making the turn to complete the racetrack one thinks...

As far as I understood from what's plotted on the charts on MaxBlow's post, they indeed flew on the 223 heading but then, for some unknown reason, instead of turning to 43 another heading was chosen which is <43 degrees and from the plots you could see the path flown is not a 180 degree right turn.

Based on these I would personally assume that from their entrance point to the racetrack (which should be <223 degrees) took them over to the mountains on the magnetic S. Having this fact in mind, they then extended their turn in order to cut runway centerline assuming still flying on the lake. Thus confidently they started the descent but ended up unfortunately in the mountains.

I am looking the charts and see the crash site between 4000 and 5000'. Looking at D5 IPT, it shows 4560'. Maybe a longshot for many but for me it is mind bothering...

However there is a major flaw in this theory: If it was possible to follow the runway lights as there was clear skies, one would definitely observe the deviations and take corrective/evasive actions. This I can't explain... :ugh:

Belgique 14th Dec 2007 06:37

The Near Side of any Dark Hill....
 
An initial investigation showed that pilot error caused the Nov. 30 crash of an Atlasjet MD83 that killed all 57 people on board, Turkish news media reported Tuesday. The wreckage was found seven miles from the airport, on a mountain around 5,000 feet high.
.
Reflect upon the "black hole" effect and the near side of intervening hills. It is possible to be seeing quite clearly the runway lights from 0.7 to 77+ miles away on a night with good visibility. However, very much "unseen" is the unlit hill between you and the airfield that increasingly juts blackly up into your flight-path. Airplanes don't necessarily go where they're pointed...... an “into wind” or underpowered flight path can often fall parabolically short (which enables the dark unseen intermediate terrain to claim its victims). It's nothing to do with "spatial consciousness", it's all to do with unseen hazards and the perils inherent in eye-balled descents and NPA's (non-precision approaches).
.
So, all the evidence thus far would seem to indicate that the crew declared themselves to be "visual" with the airfield - and that they simply flew into the near-side of a darkened mount - as their too-steep/insufficiently powered arcing descent took them latterly beneath their visual sight-line. The only chance one ever has of seeing that very subtle development happening is if there are lights very obvious in the foreground disappearing as they are subtly obliterated by the darkened hill. However such lights can easily become: “out of sight/out of mind” and those very final developments can be quite sudden. It would be careless in the extreme ever to rely upon a night visual approach and discard any requirement to observe Minimum Sector Safe Altitudes just because you can see a distant destination airfield’s lights clearly in the distance.

PBL 14th Dec 2007 06:46

LuckyStrike,

Originally Posted by LuckyStrike
As far as I understood from what's plotted on the charts on MaxBlow's post, they indeed flew on the 223 heading but then, for some unknown reason, instead of turning to 43 another heading was chosen which is <43 degrees and from the plots you could see the path flown is not a 180 degree right turn.

Please read my post concerning the Hurriyet article. I don't believe the chart with track to which you referred is an accurate rendition. They apparently flew 253° outbound, not 223°.


Originally Posted by LuckyStrike
However there is a major flaw in this theory: If it was possible to follow the runway lights as there was clear skies, one would definitely observe the deviations and take corrective/evasive actions. This I can't explain...

Aircraft don't have rear view mirrors. You can't see runway lights away from which you are flying.

BTW, it occurs to me that this progression of errors shows the value of the appropriate procedures: a parallel or teardrop entry to the holding pattern (depending on the exact direction from which they approached IPT) and *then* flying the 12 nm outbound leg of the approach from holding. The holding pattern is well protected and you get a chance to reconfirm outbound and inbound headings for the approach itself.

PBL

hetfield 14th Dec 2007 07:01


The plane disappeared from radar screens shortly before it was due to land at Isparta
Extract from posting #1.

Was it Antalya Radar?
Did the plane disappear after it entered mountaneous terrain or after the crash?

PBL 14th Dec 2007 07:49


Originally Posted by hetfield
The plane disappeared from radar screens shortly before it was due to land at Isparta ........
Was it Antalya Radar?
Did the plane disappear after it entered mountaneous terrain or after the crash?

I thought I had answered this above, but it seems I didn't. Hurriyet suggests that radar contact was lost as it descended below 8,000 ft approaching Isparta. I presume this is normal.

Since people seem to be thinking about the chart from airporthaber.com, it may be worth while to be specific about why it is likely to be misleading.

First, we do not know for sure that the aircraft approached Isparta direct from Afyon. Indeed, MachacA's chart snippet showed it on UW91, departing UW91 shortly before CRD to fly direct. So the airporthaber.com chart would be consistent with this direction of approaching Isparta.

But then the chart has him turning on the outbound course *before station passage*. Now, one supposes the runway lights were on so these might act as a reference point to anticipate the turn, but why would you anticipate the turn? You're going to have to pull a 180° procedure turn at the other end, so why do something that will misalign you on final?

But let's say he does that, and proceeds outbound on the inbound track as airporthaber.com shows. He then pulls a procedure turn to the *right* to get on the inbound track, and ends up 7nm or so away. We know he was 7 nm away from the inbound course.

Now, at 185kts max (as per the approach plate), let's say he was going 180 kts, 3nm per minute. Pulling a 180° turn takes you a minute, and you have gone half way around a circle. The circumference of your circle is two minutes in time; 6 nm. Let's say 6.28.. i.e. 2 times pi. Then your radius is about 1 nm and your diameter 2 nm, so you are 2 nm left of inbound course. How on earth could you get 7 nm away, even if you are sloppy with the turn?

So that's why I am more inclined to go with Hurriyet's 253°. But that explanation does have them coming from Afyon, not on UW91.

PBL

LuckyStrike 14th Dec 2007 15:21

PBL,

Agreed on the explanations that you have given quoting my reply... In the first part I was also trying to stress that what is plotted on the charts just can't be reflecting what happened.

And just to clarify, I am well aware of no mirror situation.:E However I was referring to the inbound leg not the outbound; so you should be seeing the airport lights. (i.e. flying at 0<x<43°)

Well anyway FDR will solve the many questions in my mind...

PBL 14th Dec 2007 16:59

LuckyStrike,

understood; thanks for the clarification.

This emphasises the point about proper procedures. Even if they had some wrong heading set, if they had entered holding first with a one-minute outbound after station passage and then a turn back inbound, as one is supposed to do, then they would have noticed visually that they were not aligned with the HIALS, which is almost aligned with the inbound course. At that point they likely would have been prompted to check and correct.

Still speculation, not confirmed by definitive course data, but looking likelier based on indirect info.

PBL

pls8xx 14th Dec 2007 18:51

Sometimes it can be useful to take a theory and review it. If found to violate a known fact, it can then be eliminated as a possibility.

With that in mind, I'll take up the supposition that the outbound leg was flown in error at heading 253 instead of the correct 223.

In the graphic below I have moved the graphics from the chart, rotated 30 degrees to the 253 heading and scaled to the google image. Another copy of the raceway is then overlaid at the turn-back position with the correct heading shown.

We might now consider what the crew expected to see near the end of the turn. Some time has passed since the outbound error was made, and a referral to the chart may have induced the crew to pull out of the turn at the chart heading of 043. They would have expected to see the runway dead ahead.

On a heading of 043, the town of Keciborlu is straight ahead at about 12 miles. The 05 runway is 30 degrees right at 12 miles. As the turn is completed, if lights at Keciborlu are visible they will be seen before the lights at the runway.

http://i9.photobucket.com/albums/a93/pls8xx/TURN.jpg

A closer look at the line of sight to these two points might be helpful. There is also the possibility that some mist has formed over the higher elevations at this time of night. Though general conditions are clear, a low line of sight over peaks may be less than perfect.

In the graphic below I show the two lines of sight that I will profile.

http://i9.photobucket.com/albums/a93/pls8xx/PHOFILE.jpg

The profile below is that to the 05 runway. A grid was selected for vertical and horizontal scale. The ground line was taken from google earth data along a line with 1 mile way-points shown. The descent profile from the chart was imported and scaled to the graphic. The descent profile was refined from the data and shown as a light blue line.

Note that the line of site from the point of turnback is just over a ridge about 3 miles from the runway. The runway will be seen from an angle, not straight on, and very early in the descent they will be lost completely, as seen by the red line.

http://i9.photobucket.com/albums/a93...x/PROFILE1.jpg

The profile from the turnback to the town of Keciborlu is a bit more interesting. Once again the lights are seen over the tops of peaks though any mist that was there. High ground near the town blocked sight of the left part of town and created a hard straight edge to the lights on that side. Lower ground slightly to the right of profile allowed some of the lights to be seen. Once again as descent progressed, all the lights would have been lost (red line). Note also the crash site suggested by Machaca lies only 0.6 mile left of this profile and the way a standard descent pattern might intersect the ground line near this point if the crew tried to pull out. This scenario would also be compatible with my earlier conclusion that the heading at impact was NE and likely close to the chart heading for final.

http://i9.photobucket.com/albums/a93...x/PROFILE2.jpg

The question now becomes, is there a known fact that would eliminate this possibility. If not, one must remember that there may well be other possibilities that also would fit the facts now known.

LuckyStrike 14th Dec 2007 19:44

Please check the aerial photo and use hybrid setting

pls8xx, that's real good piece of work you have done. However I can't hold myself down from asking this question:

After turn to final, Keciborlu lies straight ahead and along the line are 6 villages (Cukuroren, Kuyucak, Yesilyurt, Yenitepe, Senir, Kozluca together with the runway and also Keciborlu). Now, if you examine the aerial photo from a distance and the chart, you'll see that on the final leg you shouldn't be encountering any kind of light as you are flying over the lake. However if you fly the path to Keciborlu you'll be encountering more than one village with lights. That would give you a hint that you are not over the lake of course assuming no mist, no fog clear skies. At least to the co-pilot who was ex-AF...

Still, I must say I find your theory reasonably well organised.

pls8xx 14th Dec 2007 20:15

LuckyStrike, you make a very good point about lights where there should only be black water. I would think this would apply even more so on the outbound leg. Could be the outbound on 253 is plain wrong. Still, I believe it was stated the pilots were new to the area?, and the villages appear to be small. I wonder how many lights there would be at that time of night. Then there is some water where you will see the light from a boat. A pilot's past experience might dictate whether an occasional light over what he thought to be water would raise a red flag or not.

A long day, late night, and the last runway in sight. Sometimes the mind just seems to shut down.

piesupper 14th Dec 2007 21:21

lights from boat?
 
Doubtful if there would be any boats out on that lake, especially at night. Lake Burdur is alkaline and I don't think has much in the way of fish in it. Its not the tourist season and anyway this is not a particularly tourist area so there are unlikely to be any pleasure boats out either.

Towerman 15th Dec 2007 07:01

Can anyone confirm whether the Turkish authorities have introduced an age restriction on aircraft coming onto the Turkish register or operating from Turkey?

MaxBlow 30th Dec 2007 09:07

CVR u/s
 
German investigators confirmed that the CVR was u/s.
After the first techlog entry it should have been repaired within 72hrs / 3 sectors but has been flying for 9 days like this.

Green Guard 30th Dec 2007 19:56

Towerman
 

Can anyone confirm whether the Turkish authorities have introduced an age restriction on aircraft coming onto the Turkish register or operating from Turkey?
may be a naive question. Can you find any country in world with younger MD83-s then in Turkey ?
You should rather think about MaxBlow post above.
:}


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