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 17th May 2012, 04:46 #381 (permalink) Join Date: Jun 2009 Location: Jakarta Posts: 104 The photos we see are from the 1st flight of the day, so these are not the passengers that perished. Obviously the Russian pilots and crew went down in the crash. As far as the Sky Airlines cabin crew, not sure if they were on both flights. In some respects, the human face put on this crash may do more too help solve what happened and prevent similar incidents in the future. Yes, it is very sad, but the impact on the flying public, especially here in Indonesia can help improve safety And awareness in the near future.
 17th May 2012, 08:48 #383 (permalink) Join Date: Dec 2010 Location: Middle of G Age: 73 Posts: 131 Link the link wouldn´t work, also after several attempts so use the the link posted by Road_Hog - post # 337 Last edited by Annex14; 17th May 2012 at 08:51.
17th May 2012, 09:09   #384 (permalink)
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Henra :
Quote:
 The canyon ist not that wide (<1/2 mile). Assuming a speed of 200kts and the fact that they would pull max a 2G turn (probably even less) would bring them beyond the middle of the canyon when completing the turn into the canyon. (a = v^2 /r => R = v^2/ (2*9,81m/s) => Turn Radius R = 540 m = 1/3 mile.
This is wonderful in theory. I know only a tiny little bit about mountain flying, but one thing I have learned is that you do not get inside a 1/2 mile canyon below the ridges, and if you do then you stay on the sunny side, opposite to where the winds comes from and you slow down . There you might have a chance to make a 180 if the end is blocked, If you stay in the middle or on the others side , your turn will be far wider and part of it will be inside the downdraft.
As the Ziegler brothers former bosses of Air Alpes used to say : "it is far easier to teach to fly to a guy that know mountains , than to teach the mountains to an experienced pilot "

17th May 2012, 09:25   #385 (permalink)

Join Date: Jun 2009
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Quote:
 Originally Posted by annex14 the link wouldn´t work, also after several attempts so use the the link posted by Road_Hog - post # 337 Jo
That link is to part one of the article, which is worth a read.

This is the link to part two put online today.

I haven't had time to go through it yet, so I can't comment as to the quality of it,

Once again copy and paste it (copy from right to left), don't click on it.

You should read part one if you have not already read it. There is a link to it in the preface of part two.

17th May 2012, 10:17   #386 (permalink)

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Quote:
 Originally Posted by ATC Watcher There you might have a chance to make a 180 if the end is blocked, If you stay in the middle or on the others side , your turn will be far wider and part of it will be inside the downdraft.
Honestly I don't think they ever planned executing a 180 inside the canyon. even if flying close to one ridge it would be really unlikely you could do that with an airliner in a halfmile wide canyon.

And that is what puzzles me.
Let's have a look at the options:

1) Turning too early
Maybe they wanted to fly along the outside of the mountain and turned too early as per mcgyver81's theory (which really has some merit to it).
=> That would require that they couldn't see the left ridge of the canyon. That was the aspect I was referring too with my rough calculation of the turn radius. Conclusion: a normal turn would have brought them as close as a quarter mile to the left canyon wall.
They apparently flew FL2000 which is 1800m (impact at ~1850m) and thus ~200m below long parts of the left ridge which itself is slightly higher than the right ridge. So they would have to be able to see the right ridge to skim along but not the higher and probably closer left ridge. Still absolutely possible depending on local weather phenomena.

1a) Turning too early without continuous sight of the mountains
They just saw the right 'entry corner' of the canyon briefly, took it as a reference point and started turning into a direction which would lead them alongside the mountain range without seeing the right ridge after that or seeing it only intermittedly.

2) Deliberate 'canyoning'.
Requires less technical violation of Occam's razor (see explanation above) but seems so much more irresponsible to do that in an airliner in a mountaineous area with which you are not familliar that it might be less probable than the first option despite requiring less assumptions.

3) completely blind and unaware turning into the canyon thinking they are clear of the mountains.
=> Quite improbable, as that would be a hell of a coincidence not hitting any ridge prior to impact.

Did I overlook any other option?

 17th May 2012, 10:34 #387 (permalink) Join Date: Nov 2004 Location: Perth - Western Australia Age: 64 Posts: 596 Razoray - The photos circulating are definitely of an earlier flight, but the pax list of the Sukhoi shows that out of the 45 deceased pax, 11 were hosties employed by Sky Aviation, plus another two executives of the same company. That's a big hole in anyones company or organisation. Latest List Shows 45 People Aboard Crashed Sukhoi Jet | The Jakarta Globe One can speculate extensively on what caused the accident, but the entire scenario effectively screams poor flight planning (we're only going for a quick joyflight!); quite possibly inadequate pre-flight briefing; and a substantial degree of complacency on the part of the pilots. These were old, bold pilots, and they paid the ultimate price.
17th May 2012, 13:01   #388 (permalink)

Join Date: Aug 2008
Location: Germany
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Quote:
 Does it seem a bit strange that both black boxes weren't found fairly quickly once the SAR forces were on the spot?
Black boxes do not transmit their position unless they are under water (due to triggered Under Water Locator Beacons).
Only deployable Flightrecorders (which are mainly used in military aircraft/helicopter installtions) have ETL's installed which transmit their position (or the position of deployment) on 406 MHz to the satellite for locating the black boxes).

Last edited by flighttest-engineer; 18th May 2012 at 13:21. Reason: quote added

17th May 2012, 16:34   #389 (permalink)
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Quote:
 the Radar signal should have been re-aquired again on the western and northern side of the mountain,

Interesting point, but I guess the radar operator would only have got primary for a while, and that may well have been very weak even at that range.

Anyone know how long it takes for secondary display to kick back in.

(They do have secondary, don't they?)

 17th May 2012, 16:48 #390 (permalink) Psychophysiological entity   Join Date: Jun 2001 Location: A Whilom nimble brain. With 31 million posts. Age: 73 Posts: 3,378 Turning? Not a chance. When I GooEarth the eastern end of the Inn valley, it looks huge, but turning in it with a full load of pax is a very different story. I wrote this in a style appropriate for Jet Blast, but I promise you, it was a very accurate description of events on that day. http://www.pprune.org/jet-blast/3520...ml#post4548355 I remember one of my old skippers - wartime experience and all that - saying if he was confronted with a vertical wall of granite, he soar. "what else could you do?" One may well ask, though an aircraft with proper controls might well be rolled off the top of a loop, but try persuading a computer that it's a good idea.
 17th May 2012, 18:17 #391 (permalink) Join Date: Dec 2010 Location: Middle of G Age: 73 Posts: 131 Radar signal If they have Secondary it comes up imediately that the two antennas are in line of vision again, provided transponder is working. A primary target, I agree , might have been more difficult to re-aquire, not that it wouldn´t show as fast, but because of the obviously present clouds. If these had enough water or ice it will cover the Radar return at least to a very large amount.
17th May 2012, 18:19   #392 (permalink)
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henra
Quote:
 Did I overlook any other option?
Yes and not only one , there are all the technical failures possibilities , the human interferences ones , etc..
That is why it is better to wait for the CVR that will give some clues ( or perhaps not)

However in this case, in the meantime the media propaganda is likely to be in full gear: the Indonesians to prove that they did not do anything wrong, the Russians that the aircraft was not at fault and is safe to buy. So caution on what you read on the media.

loose rivets :
Quote:
 I guess the radar operator would only have got primary for a while, and that may well have been very weak even at that range. Anyone know how long it takes for secondary display to kick back in. (They do have secondary, don't they?
"Radar operators " are called Air traffic controllers today. They issue instructions if you are in IFR to keep you clear of other aircrfat and terrain.
In this case ,the R/T exchange reported in the media ( if they are correct ) would indicate that the aircraft flew VFR . If this is confirmed , then the controllers are releived from their responsibility of separate for terrain ( read flying below MSA ) and depending on the class of airspace you are in they do not have to monitor the flight on radar anymore. If you subsequently crash, of course we can find your track on the video recording, but while you crash no-one is likely to be looking at you on radar.
( excatly what happenned on the 2 recent crashs in Nepal by the way)

For your info in the XXI st century,in civilian ATC , Primary radar is the exception, SSR secondary the norm .. Return depends on Antenna rotation and availibility or not of a multiple radar tracking system , ,but to give you an idea, anything between 3 and 10 seconds.
.

 17th May 2012, 20:07 #393 (permalink) Psychophysiological entity   Join Date: Jun 2001 Location: A Whilom nimble brain. With 31 million posts. Age: 73 Posts: 3,378 Ooooo, sēmantikós! Sorrreeeee. There was an element of sarcasm in the 'they do have secondary . . .' but I don't really want to get into the relative qualities of various countries radar. Though in my day, it could be chalk and cheese. Last edited by Loose rivets; 17th May 2012 at 20:12.
 17th May 2012, 21:24 #394 (permalink) Join Date: Dec 2010 Location: Middle of G Age: 73 Posts: 131 really sorry !! Uuuuh, Ouch, that is the last I wanted to say. Intention was to say, if at that special moment Secondary was available . . . . Sorry, and please no hard feelings !!
17th May 2012, 21:45   #395 (permalink)

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Location: San Clemente, CA
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Loose rivits:

Quote:
 Turning? Not a chance. When I GooEarth the eastern end of the Inn valley, it looks huge, but turning in it with a full load of pax is a very different story.
Quote:
 I wrote this in a style appropriate for Jet Blast, but I promise you, it was a very accurate description of events on that day. I remember one of my old skippers - wartime experience and all that - saying if he was confronted with a vertical wall of granite, he soar. "what else could you do?" One may well ask, though an aircraft with proper controls might well be rolled off the top of a loop, but try persuading a computer that it's a good idea.
LOWI is tame these days for those with the equipment and training:

 17th May 2012, 22:19 #396 (permalink) Join Date: Jul 2007 Location: Germany Posts: 400 Flight simulator flyby of suspected crash location I made two flybys in the X-Plane flight simulator in an airplane of similar performance to give you an idea of the terrain of the probable crash location. This is in no way intended to be representative of the actual flight path, only to give a rough idea of what the terrain is like, to the extent of X-Plane 10's global scenery resolution. Part 1: coming in from the north Part 2: coming in from the south (The actual simulator ride is much smoother, but the video was recorded at lower framerate.) If and when flight data recorder data will be published I will probably make an animation of the actual flight path. Last edited by bsieker; 18th May 2012 at 07:37.
 17th May 2012, 23:23 #397 (permalink) Join Date: Mar 2003 Location: East of the sun, West of the moon Posts: 2,055 Bernd, thank you for this - it does indeed give a good idea of the terrain clearances and, likely, the speed at which the terrain is approached.
 17th May 2012, 23:31 #398 (permalink) Join Date: May 2012 Location: Australia Posts: 12 Thanks, Bsieker for the videos! I wonder how close the radar paths match from the morning flight?
 18th May 2012, 01:05 #399 (permalink) Join Date: Jan 2008 Location: Atlanta, GA, USA Posts: 278 bsieker, you video shows clearly that this is not a valley, but an amphitheater, as is typical of stratocone volcanoes, e.g. Mt. St. Helens, that blow their stacks.
 18th May 2012, 01:06 #400 (permalink) Join Date: Apr 2009 Location: San Clemente, CA Posts: 1,572 Bernd: Great job!
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