A Sukhoi superjet 100 is missing
Join Date: Apr 2011
Location: Cork, Ireland
Age: 55
Posts: 54
Likes: 0
Received 0 Likes
on
0 Posts
Looks like a perfectly adequate component to me, actually quite robust. I don't think it warrants being called "cheapo". It has a very clear ON/OFF display and is made of steel. Aircraft are not made like cars and there are very good reasons for keeping them simple, from reliable proven components.
Join Date: Sep 2007
Location: The 'Bat Cave' @ HLP in the Big Durian Indo
Age: 61
Posts: 781
Likes: 0
Received 0 Likes
on
0 Posts
On the switch issue it's more a question of longevity and reliability , an aviation switch like Klixon or HP can be $250 to $1,000 , many using gold plated connectors and they're usually good for 20 years of service.
This could have been a quick temporary AOG fix while waiting for proper switches to be sent out.
If you look at the panel the switches are installed in it's a plain steel plate in contrast to the backlit panels used for the other modules , I think this is a temporary installation done by the factory for some reason.
This could have been a quick temporary AOG fix while waiting for proper switches to be sent out.
If you look at the panel the switches are installed in it's a plain steel plate in contrast to the backlit panels used for the other modules , I think this is a temporary installation done by the factory for some reason.
Last edited by aseanaero; 11th May 2012 at 02:29.
Join Date: Feb 2007
Location: Expatsylvania
Posts: 179
Likes: 0
Received 0 Likes
on
0 Posts
Well yeah, they're simple switches, and they switch. No problem there. But besides them looking so different from the rest of the panel, they're not guarded and don't appear to have a stop or anything else of the sort that would prevent accidental movement. Given that it's something as important the FBW system, that's a bit unusual. The background's a different color as well, and it's also the only part of the panel where I see Cyrillic script. Of course none of this would be a big surprise for a prototype or a test bed, if they used one of those planes for the sales tour.
Wreckage or pieces?
I'm rather confused... 
On the one hand we have the pictures from the crash site, which on my admittedly brief inspection appear to show very little of any significant size left; basically indicating a high-speed impact in near level flight (assumption on my part).
On the other hand there appears to be a comment from the rescue/recovery team that the aircraft is in two (severely damaged) but identifiable pieces.
I can't imagine a scenario where the aircraft hit the cliff face resulting in anything other than total disintegration of the airframe (matching the photos), so how do the teams comments make sense?
On the one hand we have the pictures from the crash site, which on my admittedly brief inspection appear to show very little of any significant size left; basically indicating a high-speed impact in near level flight (assumption on my part).
On the other hand there appears to be a comment from the rescue/recovery team that the aircraft is in two (severely damaged) but identifiable pieces.
I can't imagine a scenario where the aircraft hit the cliff face resulting in anything other than total disintegration of the airframe (matching the photos), so how do the teams comments make sense?
Join Date: Sep 2007
Location: The 'Bat Cave' @ HLP in the Big Durian Indo
Age: 61
Posts: 781
Likes: 0
Received 0 Likes
on
0 Posts
So I guess that rules out the two fuselage half's reported earlier.
In failing light and in bad weather it would be easy to imagine what was reported.
Join Date: Mar 2008
Location: UK
Posts: 84
Likes: 0
Received 0 Likes
on
0 Posts
Just one for our ATC colleagues, if I do request a descent to below MSA in an area, what sort of response back would I expect ? Just a clearance without comment ?
.My guess is that this flight was being flown outside controlled airspace? If so, it is not being provided with an air traffic "control" service.
There are a few dependents on whether or not us controllers in England warn a pilot about descending below MSA outside controlled airspace (mainly down to the agreed level of service being provided which is normally respective with the weather conditions). However, imagining I'm providing a Sukhoi aircraft with an appropriate service outside controlled airspace and it requested/advised of descent below MSA, I would most definitely say something along the lines of:
"Caution, you will be descending below the MSA of _____ft. Taking your own terrain separation, descend at your discretion."
Join Date: Dec 2000
Location: On the equator
Posts: 1,291
Likes: 0
Received 0 Likes
on
0 Posts
Don't know whether this video has been posted on here before or not. It shows the aircraft landing and pushing back at Halim airport in Jakarta probably on the day of the cash.
If in fact the "loss of altitude for a low pass flyby of the scenery" hypothesis is true, with the number of journalists and others with cameras onboard one might assume that if any of the equipment survived the incident and is recovered it would be somewhat easily deduced from the recordings or images.
If you're looking for an investigation that assigns blame, you are going to be disappointed by the conflicting press releases.
If it's a pilot or procedural error not much will be said in the public press.
If it's an aircraft system error then a hint might come from the order book.
Since the aircraft is not yet in service press topics serve no purpose
in summary, much will be done behind the scenes to ascertain the cause, but little satisfying press releases.
If it's a pilot or procedural error not much will be said in the public press.
If it's an aircraft system error then a hint might come from the order book.
Since the aircraft is not yet in service press topics serve no purpose
in summary, much will be done behind the scenes to ascertain the cause, but little satisfying press releases.
Sam - welcome to PPRuNe.
You, and a few other posters commenting on the TAWS switch-lights have it right.
The TAWS can be turned off, without affecting GPWS Modes 1 - 5.
If the GPS position is inaccurate, TAWS will not be available.
I had assumed that the reason for the TAWS Display On-Off switch was to be able to choose between the radar display and the TAWS display when both may have been required. In our ops, at least one pilot had to have TAWS ON in designated mountainous terrain - so if radar was also required, the TAWS switch was ON for one ND and OFF for the other. If the TAWS system had a warning, both NDs displayed the warning and the terrain ahead.
Of course, the question is, was the TAWS turned off on this flight, and if not, what did the TAWS do just prior to impact? Were there warnings - how soon - was there a response from the crew?
Google-Earth images deleted due updated data.
PJ2
You, and a few other posters commenting on the TAWS switch-lights have it right.
The TAWS can be turned off, without affecting GPWS Modes 1 - 5.
If the GPS position is inaccurate, TAWS will not be available.
I had assumed that the reason for the TAWS Display On-Off switch was to be able to choose between the radar display and the TAWS display when both may have been required. In our ops, at least one pilot had to have TAWS ON in designated mountainous terrain - so if radar was also required, the TAWS switch was ON for one ND and OFF for the other. If the TAWS system had a warning, both NDs displayed the warning and the terrain ahead.
Of course, the question is, was the TAWS turned off on this flight, and if not, what did the TAWS do just prior to impact? Were there warnings - how soon - was there a response from the crew?
Google-Earth images deleted due updated data.
PJ2
Last edited by PJ2; 11th May 2012 at 15:04.
Join Date: Nov 2008
Location: USA
Posts: 22
Likes: 0
Received 0 Likes
on
0 Posts
The TAWS is ACSS T2CAS according to Sukhoi's webpage here: Sukhoi Company (JSC) - Airplanes - Civil aviation - Sukhoi Superjet 100
This same TAWS is optionally installed in Airbus A320 (instead of Honeywell EGPWS), so it's not surprising the TAWS control panel looks identical. You can see an interactive Airbus TAWS control panel here: A320 Ground Proximity Warning System (GPWS) & Cockpit Voice Recorder (RCDR)
The TAWS "TERR" button is a locking switch/annunciator. It displays FAULT when the TAWS functions are not working (due to lack of power, or IRU, or position, etc) and when the switch is depressed it will display OFF to indicate the TAWS functions have been manually inhibited. I don't think OFF illuminates for faults, otherwise the crew would not know the position of the terrain inhibit switch (active, deactive).
If they were flying low to give the passengers a thrill, it is likely they would have activated the terrain inhibit.
This ACSS T2CAS has a unique feature that voices "Avoid Terrain" instead of "Terrain Terrain Pull Up" if it believes (based on the internal terrain database) that the aircraft might not be able to out-climb the terrain. In that case, the crew is supposed to turn the aircraft instead of performing max climb. Of course, which way to turn will be based on the terrain display so hopefully the terrain database and the position of the aircraft are correct, otherwise the pilot could be mis-led into turning toward higher terrain instead of away from it!!
This same TAWS is optionally installed in Airbus A320 (instead of Honeywell EGPWS), so it's not surprising the TAWS control panel looks identical. You can see an interactive Airbus TAWS control panel here: A320 Ground Proximity Warning System (GPWS) & Cockpit Voice Recorder (RCDR)
The TAWS "TERR" button is a locking switch/annunciator. It displays FAULT when the TAWS functions are not working (due to lack of power, or IRU, or position, etc) and when the switch is depressed it will display OFF to indicate the TAWS functions have been manually inhibited. I don't think OFF illuminates for faults, otherwise the crew would not know the position of the terrain inhibit switch (active, deactive).
If they were flying low to give the passengers a thrill, it is likely they would have activated the terrain inhibit.
This ACSS T2CAS has a unique feature that voices "Avoid Terrain" instead of "Terrain Terrain Pull Up" if it believes (based on the internal terrain database) that the aircraft might not be able to out-climb the terrain. In that case, the crew is supposed to turn the aircraft instead of performing max climb. Of course, which way to turn will be based on the terrain display so hopefully the terrain database and the position of the aircraft are correct, otherwise the pilot could be mis-led into turning toward higher terrain instead of away from it!!
Last edited by GroundProxGuy; 10th May 2012 at 17:10.
PJ2,
On our Airbii the Terr pb being off on the overhead would disable the EGPWS and the NDs would not receive the terrain ahead caution/warning. The pop up feature is only available if the overhead pb is on and the TERR on NDs pbs are off.
The TAWS pb might have been switched off routinely as the system had no terrain clearance info for that airfield and runway.
On our Airbii the Terr pb being off on the overhead would disable the EGPWS and the NDs would not receive the terrain ahead caution/warning. The pop up feature is only available if the overhead pb is on and the TERR on NDs pbs are off.
The TAWS pb might have been switched off routinely as the system had no terrain clearance info for that airfield and runway.
Last edited by Right Way Up; 10th May 2012 at 16:07.
Join Date: May 2012
Location: WSSS
Age: 43
Posts: 1
Likes: 0
Received 0 Likes
on
0 Posts
It seems the picture circulating is actually from the AirBlue crash.
Citing AVHerald:
"There are photos circulating the Internet and in Media that pretend to be of the crash site at Mount Salak, however, in reality show the Airblue A321 which crashed in Pakistan, see Crash: AirBlue A321 near Islamabad on Jul 28th 2010, impacted mountaineous terrain near the airport."
Crash: Sukhoi SU95 over Indonesia on May 9th 2012, aircraft impacted mountain
Citing AVHerald:
"There are photos circulating the Internet and in Media that pretend to be of the crash site at Mount Salak, however, in reality show the Airblue A321 which crashed in Pakistan, see Crash: AirBlue A321 near Islamabad on Jul 28th 2010, impacted mountaineous terrain near the airport."
Crash: Sukhoi SU95 over Indonesia on May 9th 2012, aircraft impacted mountain
Join Date: Jan 2006
Location: US
Posts: 2,205
Likes: 0
Received 0 Likes
on
0 Posts
Having done a short internship with the NTSB many many moons ago and been to many CFIT accidents, it never ceases to amaze me how many occur within less than 100' of passing over the obstacle...
The difference between where the plane is pointing and where it's actually going? AOA.
The difference is very obvious on fighter a/c performing at airshows.
Re TAWS switch operation; see incident #8 (A320) below.
Selecting TERR OFF inhibits the Enhanced modes (Look-Ahead/Map), but the original GPWS modes still work (N.B. Could have been a Honeywell installation).
http://www.icao.int/fsix/_Library%5C...plus%20add.pdf
Selecting TERR OFF inhibits the Enhanced modes (Look-Ahead/Map), but the original GPWS modes still work (N.B. Could have been a Honeywell installation).
http://www.icao.int/fsix/_Library%5C...plus%20add.pdf
I have done many demo flights when working for aircraft manufacturers. There is a tendency for the VIP's on board (most of whom know SFA about aviation) to want to see the aircraft do manoeuvres that are outside of the normal civil operating envelope. Pressure can be put on the crew to demonstrate the agile manoeuvrability as the aircraft has low fuel and payload. Most of the time it is pulled off without consequences. This could well be one of those times it went wrong.
Before assuming that both left- and right-hand seats were necessarily occupied by the Sukhoi crew at the time of the accident, it might be a good idea to wait for the CVR, if it's recoverable.
Join Date: Sep 2007
Location: The 'Bat Cave' @ HLP in the Big Durian Indo
Age: 61
Posts: 781
Likes: 0
Received 0 Likes
on
0 Posts
in summary, much will be done behind the scenes to ascertain the cause, but little satisfying press releases.