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1  NCO Club: Off Topic Discussions / The Aisles: Non-military News and Snippets / Re: A-380 emergency landing! on: 15 November 2010, 20:53:54
So in effect the scavange side if the bearing box was blocked by debris causing the oil level to increase and overwhelm the labyrinth seal which then dumped too much oil onto the hot side of the turbine. Fire ensues and the turbine ultimately fails. Interesting development, again, luckily not a major disc problem.
2  War & Conflicts Discussions / World War I / Re: Armistice Day on: 14 November 2010, 21:53:41
In the corner of a foreign field
3  NCO Club: Off Topic Discussions / The Aisles: Non-military News and Snippets / Re: A-380 emergency landing! on: 12 November 2010, 22:32:48
Turbine stages (especially the HP) are usually protected with impinging cooling air blown over the blades, this is normally tapped off the compressor from the latter stages so that the temperature differential isn't too high. It is normally blown either through the turbine shaft, disc and through the blades, or around an anullar ring and through the stator blades. I couldn't see any evidence of cooling ducts in the disc in the photo.
I would imagine, looking at the disc piece that the bearing gave way first and the turbine 'followed on'.
Having said that the disc is somewhat different to what I am used to in gas turbines, alot thinner than I would expect. Mind you the number of compressor stages required have been dramatically reduced over the last two decades.
4  NCO Club: Off Topic Discussions / The Aisles: Non-military News and Snippets / Re: A-380 emergency landing! on: 11 November 2010, 19:24:04
So it could well be oil lines adrift. That is fortunately an easier fix than a turbine disc redesign.
5  NCO Club: Off Topic Discussions / The Aisles: Non-military News and Snippets / Re: A-380 emergency landing! on: 10 November 2010, 22:56:25
Indeed many questions.
I have just read that the Trent does drive it's generators off the IP which I find surprising. The normal architecture of multi-spool engine has the HP spool on the outside making it the easiest to fit a PTO for your extra's (fuel pump,oil pump etc). That photo is what happens when a turbine disc enters a fuel tank (two in the case of XL232). There wasn't much left when the flames died down. Fortunately no casualties.
6  Military Hardware, Gear and Equipment / Aerial Equipment / Re: Hawker Hurricane: 75 years ago: November 6 1935 on: 10 November 2010, 22:13:39
I agree with you Rattler, the Hurri was inferior to the Bf109 which is why it was sent after the bombers (the higher percentage of victories is then clear).I do believe in reality the 109 had a tighter circle than both the Hurri and the Spit. I also read somewhere that one of the test a/c had it's wings ripped off during some high 'G' so I'm not surprised that the average pilot wouldn't fly it to 10/10ths
7  NCO Club: Off Topic Discussions / The Aisles: Non-military News and Snippets / Re: A-380 emergency landing! on: 10 November 2010, 22:03:07
By geared disc am I to assume they mean the PTO for the ancilliaries? It would explain the bell forming on the inner edge. That would make it a HP disc and as good is, the first. If so, it could have been far worse.
8  NCO Club: Off Topic Discussions / The Aisles: Non-military News and Snippets / Re: A-380 emergency landing! on: 10 November 2010, 08:09:12
Good points Rattler.
I'm also familiar with the Tyne.
I was a little unsure as to the id of the disc. It had been named as a comp disc failure by a fair number of people who I thought knew their stuff.
My first thought seeing it was turbine judging by the blade mounting (fir tree) compressors are normally pinned into place. However the disc is a lot thinnier than I would expect, especially in a HP turbine (judging by the size).
Disc failure due to bearing failure? Hmm.
It is certainly a stress induced failure, that much can be seen by the size of the remnant.
9  NCO Club: Off Topic Discussions / The Aisles: Non-military News and Snippets / Re: A-380 emergency landing! on: 9 November 2010, 20:08:40
As far as the RR engine and the oil found, it is now under investigation whether this is a resnance leak caused by the higher power of the Quantas models (compared to Lufthansa, e.g.).

Hmm, I find that a little strange. Vibration loosening an oil line. All bolts/nuts/flange nuts are generally locked in some way (self locking nut, spring rings, locking tabs or wire) vertainly in something as important as engine oil. Vibration fretting gaskets? Not something I'd expect. Any cracking of oil lines would give large oi; leaks but could be easily solved by changing the lemgth of the affected lines. Gas turbines are notorious for destructive frequencies. If you have ever looked closely at all the plumbing you will notice that a great number of pipes have extra length and seemimgly unneccessary bends and loops. They are normally there to counter resonance frequencies.
10  NCO Club: Off Topic Discussions / The Aisles: Non-military News and Snippets / Re: A-380 emergency landing! on: 9 November 2010, 07:21:45
Indeed, just like a car, if the cost of repair is higher than a certain percentage of the book value then the insurance company will write it off.
The owner may buy it back if they wish and rebuild it, even if it costs more. They rarely do that obviously.
11  NCO Club: Off Topic Discussions / The Aisles: Non-military News and Snippets / Re: A-380 emergency landing! on: 8 November 2010, 07:34:21
Yep, the wing fix will be leaving a few engineers scratching their heads for a while. I know that the wing is a one-piece structure but I don't know how it's built. I assume that it's two chemically milled skin sections joined together with internal struts. A very strong wing but incredibly difficult to repair. BDR repairs tended to involve a sheet of mild steel (6mm thick) and Jo-bolts.
I hadn't heard of the engine overspeed, I assume that there is a mechanical governer as well as the FADEC to ensure the engine never exceeds design limits. It would be interesting to see how much it oversped.
12  NCO Club: Off Topic Discussions / The Aisles: Non-military News and Snippets / Re: A-380 emergency landing! on: 7 November 2010, 21:52:43
A few things Rattler.
1. It does look like a compressor disc, it also ruptured in the classic 1/3-2/3 with probably a third small piece broken off.
2. A disc failure is almost never contained certainly the rear discs (larger and more mass)
3. Design flaw? Possible but more likely a fabrication fault.
4. Maintenance fault? Again possible, I would have to see the maintenance records to see if any engine modules were replaced.
5. The FADEC problem on number one will cause a few red faces, both at Airbus and RR. Indeed a FADEC engine will maintain the last selected thrust when there is a total failure of power. That might be a carry-over from a Tornado accident in 1983 where the a/c experienced a total power failure and both engines ran away and failed.
<a href="http://www.mod.uk/NR/rdonlyres/77186A18-0C22-43CA-AA81-4A64C4E600D8/0/maas83_22_tornado_gr1_za586_27sept83.pdf" target="_blank">http://www.mod.uk/NR/rdonlyres/77186A18-0C22-43CA-AA81-4A64C4E600D8/0/maas83_22_tornado_gr1_za586_27sept83.pdf</a>
13  Military Hardware, Gear and Equipment / Aerial Equipment / Re: Aerial equipment: videos on: 24 October 2010, 19:16:55
What I see on the film is that he came in too hot, realised at the last moment and tried to correct. That's when it seemed to stall.
I'll dig around for more info
14  NCO Club: Off Topic Discussions / The Blackboard: Posts Related To Calendar Entries / Re: Don Moore (1946-2009) 1 year missed on: 6 March 2010, 22:16:05
Indeed, RIP.
There's nothing more to add.
15  The Military / Humor, Jokes and Fun in the Military / Re: New Spanish Subs on: 11 February 2010, 21:06:08
Read this snippet on another forum, sort of makes sense to some point:

Quote
The Spanish are all excited to see their new submarines ready to
deploy. These beautifully designed subs have glass bottoms so the new
Spanish navy can get a really good look at the old Spanish navy.


Smiley

Rattler

I assume then that they will be patrolling the North sea and the coast of Scotland?
16  War & Conflicts Discussions / 35t & 38t / Re: Pz III TNHP (Model H) on: 11 February 2010, 21:04:07
Yes, it is a Pzkpfw 38(t) as opposed to the later 38(d) version.
17  NCO Club: Off Topic Discussions / The Lounge - Get A Beer & Just Chatter Away / Re: The Omnipresent, currently playing (music) thread... on: 4 February 2010, 21:16:32
Nice Matt.
What would appear to be a contradiction in terms, Pink Floyd and blues, but Dave Gilmour did start out in a blues band.
Pink Floyd - More Blues

And
Pink Floyd - Seamus The Dog

This is the dog they used for Seamus.
A somewhat different style of blues, tight and ordered, not everybodies taste. I think it works though.
18  NCO Club: Off Topic Discussions / The Lounge - Get A Beer & Just Chatter Away / Re: The Omnipresent, currently playing (music) thread... on: 3 February 2010, 00:51:42
Herman does his try-outs some 10 kliks from where I live. I've seen him quite a few times now. He's still good.
19  NCO Club: Off Topic Discussions / The Lounge - Get A Beer & Just Chatter Away / Re: The Omnipresent, currently playing (music) thread... on: 2 February 2010, 20:50:59
The Dutch music scene has produced a wide variety of good artists.
De Dijk - Als Ze Er Niet Is (External Embedding Disabled)
Another one, very '80's but a great number.
Golden Earring - When The Lady smiles

And mixture of Dutch and Belgium, somewhat older and more sedate but I think a good translation from the original French.

Herman van Veen : Een Vriend Zien Huilen

The original is called Voir Un Ami Pleurer by Jacques Brel
20  NCO Club: Off Topic Discussions / The Lounge - Get A Beer & Just Chatter Away / Re: The Omnipresent, currently playing (music) thread... on: 1 February 2010, 23:33:10
Another couple of nice Belgian numbers
K's Choice - Not An Addict (European version)

K's Choice - Everything for free


The first one just gives me goose bumps evrytime I hear it.

And of course we couldn't forget
Vaya con dios - Heading for a fall
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