Go Back  PPRuNe Forums > Flight Deck Forums > Rumours & News
Reload this Page >

BREAKING NEWS: airliner missing within Egyptian FIR

Rumours & News Reporting Points that may affect our jobs or lives as professional pilots. Also, items that may be of interest to professional pilots.

BREAKING NEWS: airliner missing within Egyptian FIR

Old 10th Nov 2015, 19:44
  #2061 (permalink)  
 
Join Date: Mar 2007
Location: Canada
Age: 53
Posts: 8
Using an image from post 2049, we might be able to gain more understanding about the force(s) that broke the APU/tail cone section off the fuselage:

The mysterious hole seen in the APU fwd firewall appears to have been elongated by what seems to be a harness of Tefzel wires. That is to say, whatever forces were involved here were
strong enough to break the 4 mount points but not enough to rip this harness clean. Incredibly, that section had to remain attached for an amount of time while the hole was being distorted.

And for the critics, I consider my post to be 90% observation and 10% speculation.


Last edited by VNee; 10th Nov 2015 at 20:09. Reason: Please resize image if displaed on PPRuNe. Too large. Now 15% smaller -VNee
VNee is offline  
Old 10th Nov 2015, 20:12
  #2062 (permalink)  
 
Join Date: Mar 2014
Location: WA STATE
Age: 74
Posts: 1
Question HS flopping speculation

#2078 (permalink)

The residue would be minimal- and in the airstream might be well dispersed- in addition the 'blast' and smoke would be minimal

AND pretty much limited to the sections/skins/and pieces like HS "wing" box we have not seen, but which must have been present when finding the CVR and FDR.
While there may be some residue on the pieces we have seen- it would not be obvious just from the photos available

Minimum shrapnel also
CONSO is offline  
Old 10th Nov 2015, 20:26
  #2063 (permalink)  
 
Join Date: Jan 2008
Location: Hotel Sheets, Downtown Plunketville
Age: 72
Posts: 0
Originally Posted by CONSO View Post
#2078 (permalink)

The residue would be minimal- and in the airstream might be well dispersed- in addition the 'blast' and smoke would be minimal

AND pretty much limited to the sections/skins/and pieces like HS "wing" box we have not seen, but which must have been present when finding the CVR and FDR.
While there may be some residue on the pieces we have seen- it would not be obvious just from the photos available

Minimum shrapnel also
Cannot agree with above, for answers see Pan Am 103, in particular:

"DERA's Feraday and Dr. Thomas Hayes examined two strips of metal from AVE 4041, and found traces of pentaerythritol tetranitrate (PETN) and cyclotrimethylene trinitramine, components of Semtex-H, a high-performance plastic explosive manufactured in Pardubice, Czechoslovakia (now Czech Republic)"

Pan Am was also at 31000 feet and at similar speed when it was brought down.

Unless, since then technology in armaments and explosives have advanced to a capability of manufacturing bombs that on detonation leave no residual trace whatsoever, it would be a certain bet it will be found.
Chronus is offline  
Old 10th Nov 2015, 20:30
  #2064 (permalink)  
 
Join Date: Aug 2009
Location: Texas
Age: 60
Posts: 5,448
Russian communications intercepted by U.S. intelligence agencies showed Russia believed the plane that crashed in Sinai, Egypt, on Oct. 31 was brought down by a bomb, U.S. sources familiar with the matter said on Monday
I really wish these "sources" would shut the hell up. Then again, this really does not make the Intel folks look good. "We heard the Russians talking about it, therefore we think it was a bomb, so we told them, in effect feeding them their own work as our 'intel assistance'" isn't what I'd call exceptional Intel work.

I expect that this might be a purposeful leak used as a smokescreen. Actually, I hope it is or my worries on who is guarding the zoo in the Intel world will have increased.

As noted above, all this talking around the problem has hit the Egyptian tourist industry in the chest with a spike. Not good.

Last edited by Lonewolf_50; 10th Nov 2015 at 22:23.
Lonewolf_50 is offline  
Old 10th Nov 2015, 20:35
  #2065 (permalink)  
 
Join Date: Sep 2005
Location: Moscow, Russia
Posts: 1,022
Chronus, if you know where to look, make analysis will be piece of cake. Otherwise, you must collect samples from any suspicious part and lab test them until you found what you looking for. It's also answers question "why two weeks" - not because each test is slow, but because there is a looooot of samples.
Kulverstukas is offline  
Old 10th Nov 2015, 20:38
  #2066 (permalink)  
 
Join Date: Sep 2014
Location: Budapest
Posts: 1
Bombing accidents/time required

Smot911

"Does it really take a week to analyze possible explosive traces, or is somebody buying time?"

Lockerbie: they found PETN and other tracks after a week.
UTA-772: a week or more (investigation in France).
https://en.wikipedia.org/wiki/UTA_Flight_772

IIRC in both cases investigators also found the parts of timer.
Both cases require hundreds of soldiers to collect all possible parts, in second case investigation says they collect 15 tons of debris to check the explosive traces.

However, despite we are in 2015 the basic components of explosives are the same (like PETN). There are more sophisticated explosives, but hardly available for terrorists I think.

Anyway, there is a list if someone want search similarities or differences.
https://en.wikipedia.org/wiki/Timeli...ombing_attacks
BigaC is offline  
Old 10th Nov 2015, 20:44
  #2067 (permalink)  
 
Join Date: Mar 2014
Location: WA STATE
Age: 74
Posts: 1
#2081 (permalink)
Cannot agree with above, for answers see Pan Am 103, in particular:
Note i didn't say NO residue - just that obvious signs like shrapnel and smoke would be mostly on the parts we have not seen.
And if chem residue in small quantities ( as compared to a suitcase style bomb or one in a container ) is still present on the pieces left for photos- it would not be obvious from the photos.

Unfortunately , everyone thinks of an explosive leaving a major size flash and smoke as in pearl harbor or similar- or blowing the whole plane apart, etc

And if many parts/sections b must be examined - it does take time
CONSO is offline  
Old 10th Nov 2015, 20:55
  #2068 (permalink)  
 
Join Date: Apr 2008
Location: Paris
Age: 70
Posts: 275
Explosives leave residue. Hence:

Residue ==> confirmed explosive device. ==> set loose the terror cops.
No residue ==> no explosive.
No explosive ==> probable mechanical failure. ==> set loose the airframe inspectors.

Edmund
edmundronald is offline  
Old 10th Nov 2015, 20:58
  #2069 (permalink)  
 
Join Date: Jan 2008
Location: Hotel Sheets, Downtown Plunketville
Age: 72
Posts: 0
Originally Posted by Kulverstukas View Post
Chronus, if you know where to look, make analysis will be piece of cake. Otherwise, you must collect samples from any suspicious part and lab test them until you found what you looking for. It's also answers question "why two weeks" - not because each test is slow, but because there is a looooot of samples.
Not uttered a word about pieces of cake. Air crash investigation is a painstaking
task, am sure that with such a landmark event, not a single piece of stone will be left unturned, let alone the wreckage that lays scattered on that stone and rock strewn desert.
Chronus is offline  
Old 10th Nov 2015, 21:56
  #2070 (permalink)  
 
Join Date: Jan 2008
Location: Somerset
Posts: 17
Prada
that pivot point pic is v useful, thanks.


I am slightly confused, being more used to tiny simple planes. If I am wrong please enlighten me.

The jackscrew is the means of trimming the HS +/- by small increments, and would not be able to rapidly change the AofA of the HSs. The bottom bracket or trunnion of the JS must be linked in some way to the main pivot bearings further aft, otherwise the HSs could not articulate.

Large and speedy increments or decrements of the HS are generated by the elevators on the trailing edge.

If the JS- for whatever reason - becomes detached, the HSs will align (as you suggest) with the immediate airflow at the tail, and the trimming effect will be lost.

Would loss of the jackscrew (and hence taking away of trim) result in the PF making a quick reaction to re-trim using the elevators, and could this cause a full scale deflection + or- of the HS, unmoderated or even jammed by the broken JS ?

I'm trying to work out the consequences of a single point of failure loss of the JS.
sarabande is offline  
Old 10th Nov 2015, 22:03
  #2071 (permalink)  
 
Join Date: Jun 2009
Location: London, UK
Age: 42
Posts: 46
Presence or absence of explosive residue determining likely cause.

Question. What if malefactor ...?
I've been pondering similar for the last few days.

An explosive or mechanical device wasn't even needed. Just access to the aircraft for someone with a couple of tools and a basic knowledge of flight dynamics (and/or directed by someone who had more advanced knowledge). The aircraft was on the ground for 12 hours, possibly unsecured. Various acts* of mechanical sabotage could have taken place in that time.

In my eyes, sabotage undetectable to the naked eye or sniffer dogs could be far more dangerous than explosives.

However, why did nothing happen until that particular altitude? If the airframe was seriously compromised, wouldn't something have happened/been detected earlier, even just an erroneous sensor reading or vibration? Would it have even left the ground?


*public forum - unsure whether we want to discuss exact details here?

Last edited by papershuffler; 10th Nov 2015 at 22:23.
papershuffler is offline  
Old 10th Nov 2015, 22:20
  #2072 (permalink)  
 
Join Date: Jul 2006
Location: UK
Posts: 35
Originally Posted by Control Eng View Post


If that force was due to impact by the HS and/or pivot assembly, it is inconceivable that the frame would not be totally distorted.
I take your point re this. As I'm seeing it up to now, the HS goes down, the lower edge of the HS pivot attaching lug striking the connecting pin/bolt/casting which connects the two halves of the 'sandwich'. This causes the pivot mounting to twist around the HS pivot, with aerodrag on the HS causing the lower pinion to push backward onto the APU cone, twisting the lower supporting frame with it. What you then have is the length of the pivot mount sandwich prising away the APU cone at the lower end below the slot, the two halves of the sandwich exerting equal force on the inner and out edges of the APU cone surround frame on both sides.

The key to why the surround doesn't distort could be in the alignment of the cone attachment lugs at the top - they are vertical - so as the pivot mounts force out the lugs at the bottom, the top end opens up like a hinge.

Having said all that though...
Bertie Bonkers is offline  
Old 10th Nov 2015, 22:20
  #2073 (permalink)  
 
Join Date: Jun 2008
Location: Ventura, California
Age: 61
Posts: 257
How? Posts

How it could be done speculation is unwise in my opinion. It rarely seems to be moderated out, and many of us probably learned enough in high school chemistry to come up with numerous vectors.

With a forum as widely read as PPRuNe, participants should assume that at least some viewers have less than noble intentions, and exercise appropriate discretion.

Far back in this thread I posted one such speculation, not quite the full recipe but enough to make further research simple. Within a few minutes someone else (thank you whoever you were) suggested it might not be such a good idea for the reasons stated above.

My post now reads "Deleted by author."
thcrozier is offline  
Old 10th Nov 2015, 22:20
  #2074 (permalink)  
 
Join Date: Mar 2009
Location: us
Age: 59
Posts: 212
Apparently field tests for the most common explosives found nothing so they are testing now for homemade\exotics.

Which begs the question why would ISIS do that, aren't there plenty of commercial/military explosives available in the Sinai already.
vovachan is offline  
Old 10th Nov 2015, 22:27
  #2075 (permalink)  
 
Join Date: Jun 2008
Location: Ventura, California
Age: 61
Posts: 257
A little study on devices used in the past should help you understand.
thcrozier is offline  
Old 10th Nov 2015, 22:30
  #2076 (permalink)  
 
Join Date: Mar 2014
Location: wales
Age: 77
Posts: 316
Jdamnation http://www.pprune.org/rumours-news/5...ml#post9176759

Two ways to do that are risky

a) go out to aircraft alone - risky someone may question why or caught on cctv
b) have it in pocket whilst loading (or unloading bay), you may get detected with it or placing it.

If a bomb in that compartment it was almost certainly in baggage, enough reports that scanning was inept at best.

Thinking ahead:-

I am ony aware of 1 bomb that was placed in an aircraft (toilet) as opposed in passenger luggage (inc cabin)

If this were to turn out to be the scenario, the question of on ground aircraft security arises, to the best of my knowledge no external hatches or doors are lockable perhaps they will need to be made secure in some way.

Remembering the reactions to 911 will we see something along these lines.

Aircraft having a alarm system like a shop set by crew on leaving, can only be reset from flight deck which is locked, so access not prevented but is known.

Perhaps an extra ad hoc cabin crew member who does not leave until cleaning, refuelling, cleaning, baggage unloading is complete is complete, same person would have to be there prior to main crew to give access to catering and refuelling (if not done earlier), sort of like a junior crewchief.
oldoberon is offline  
Old 10th Nov 2015, 22:31
  #2077 (permalink)  
 
Join Date: Jul 2006
Location: UK
Posts: 35
Originally Posted by vovachan View Post
Apparently field tests for the most common explosives found nothing so they are testing now for homemade\exotics.

Which begs the question why would ISIS do that, aren't there plenty of commercial/military explosives available in the Sinai already.
And would you not actively seek to leave a trace to show you did it?
Bertie Bonkers is offline  
Old 10th Nov 2015, 22:36
  #2078 (permalink)  
I don't own this space under my name. I should have leased it while I still could
 
Join Date: Dec 2002
Location: Lincolnshire
Age: 76
Posts: 16,646
Vovochan, simple. Common known explosives are detectable by equipment so designed to detect them. This is true of any detection system, they are reactive.

The shoe bomber evaded detection. The liquid limit again came in after first use
Making phones and laptops power up was yet another.

Now I know two common similar objects could be designed to by pass security ONCE. I know another common item that could be redesigned for several purposes but still pass the scanners.

And a friend showed me another common item that 99% carry but is lethal in trained hands.

These devices are so far undetected but are never the less known about.
Pontius Navigator is offline  
Old 10th Nov 2015, 22:59
  #2079 (permalink)  
 
Join Date: Apr 2013
Location: In the electronics bay!
Posts: 22
Originally Posted by Bertie Bonkers View Post
I take your point re this. As I'm seeing it up to now, the HS goes down, the lower edge of the HS pivot attaching lug striking the connecting pin/bolt/casting which connects the two halves of the 'sandwich'. This causes the pivot mounting to twist around the HS pivot, with aerodrag on the HS causing the lower pinion to push backward onto the APU cone, twisting the lower supporting frame with it. What you then have is the length of the pivot mount sandwich prising away the APU cone at the lower end below the slot, the two halves of the sandwich exerting equal force on the inner and out edges of the APU cone surround frame on both sides.

The key to why the surround doesn't distort could be in the alignment of the cone attachment lugs at the top - they are vertical - so as the pivot mounts force out the lugs at the bottom, the top end opens up like a hinge.

Having said all that though...
Simple mechanics of levers - if you apply a force half way along a lever to exert a force at the end of a lever, then the original force has to be twice the magnitude.

The resultant force ripped the mountings out of the framework and twice the force did not distort the framework - no!

The whole 'loss of HS control' theory is a non starter without tail cone damage in this area.
Control Eng is offline  
Old 10th Nov 2015, 23:13
  #2080 (permalink)  
 
Join Date: Sep 2008
Location: 41S174E
Age: 52
Posts: 2,767
Aircraft having a alarm system like a shop set by crew on leaving, can only be reset from flight deck which is locked, so access not prevented but is known.

Perhaps an extra ad hoc cabin crew member who does not leave until cleaning, refuelling, cleaning, baggage unloading is complete is complete, same person would have to be there prior to main crew to give access to catering and refuelling (if not done earlier), sort of like a junior crewchief.
Non of that prevents a baggage handler simply leaving their smart phone in the hold as they finish up their job.
framer is offline  

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information

Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.