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Airbus: A380 has a weight problem

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Airbus: A380 has a weight problem

Old 9th Jul 2004, 06:31
  #41 (permalink)  
 
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I fail to get this point about 1.3 seconds per evac.

By using the same logic

777-300: 434 seats (and that isn't even the max).
10 doors, half shut off.
87 pax per door.
90 seconds.
1.03 seconds per pax.

With regards to the three engined 747, are you thinking of this?



In which case, this is a 747-300 proposal concieved well after EoS of the 747-100.

I share the scepticism of others as to whether the original 747 was ever planned with a full length upper deck.
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Old 9th Jul 2004, 07:02
  #42 (permalink)  
 
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That Picture configuration of the 3 eng 747 was considered for the SP type but because of the massive difference in structure of the wing and and tail section, it was not a goer.
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Old 9th Jul 2004, 09:19
  #43 (permalink)  
 
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I cannot confirm that Airbus plan a double slide for the upper deck. The 747-400 slides are. I would be surprised if they were not planned to be so because of torsional twisting problems- it would be harder to keep a long slide like that untwisted in wind. The nightmare video of the Pan Am SFO take-off incident where extensive hydraulics failure caused a tip back after landing and the slides flailing in the downdraft of the helicopters buzzing around filming with people falling off them must never be repeated, not from that height!
I actually think the upper deck will be a slightly safer place to fly. You have more 'padding' below you. I'm familiar with the operation of the upper deck slides and have no doubt they are virtually as good as the lower deck ones. I would assume the same manufacturers will produce them and they have the benefit of 20 years progress in slide technology on the -400.
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Old 9th Jul 2004, 11:35
  #44 (permalink)  
 
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16 doors in total - Diehl

"The Airbus A380 will be the first commercial aircraft equipped with a doors and slides management system. In its basic version A380-800, the Airbus will have sixteen passenger and two cargo doors. In order to maximize handling comfort and safety - especially in case of the emergency - doors and hatches will be centrally monitored and electrically actuated through the DSMS for the first time.

The DSMS consists of electronic computers, sensors, and actuators. The core of the DSMS is the doors and slides management control unit (DSMCU), a central computer where all status and control data for doors, hatches, and escape slides are gathered. In addition, there is a local door controller (LDC) installed in every door to individually control every single door. Each LDC has an emergency power supply allowing the doors to be opened even in the event of a failure of the main power buses in the aircraft. Special sensors are meant to determine the position of the body after emergency landing to make sure that the escape slides will be extended to the correct length."
-----------------------------------------------------------

There are eight slides a side: six on the upper deck, eight on the main-deck doors, and two on the wing/belly fairing. Each is 15m (49ft) long.

With complex underside bracing for rigidity, all the slides except the single-track wing/belly units will accommodate two people side-by-side. The wing/belly slides run parallel with the fuselage until they reach the wing trailing edge, then slope down.


FAA overview
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Old 9th Jul 2004, 12:49
  #45 (permalink)  
 
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FAA OVERVIEW

I WOULD HAVE LIKED TO SEEN THAT OVER VIEW BUT LINK IS NOT WORKING.

LOOK;

BOEING AND AIRBUS KNOW HOW TO DESIGN PLANES. WITH THE ADVENT OF CAD/CAM AND ALL THE COMPUTER PROCESSING POWER AVAILABLE TODAY I AM CONFIDENT THE 380 WILL SUCCEED ONCE BUILT.

THE WEIGHT ISSUES WILL CONTINUE AND THEY WILL LIKELY FIND REMEDIES FOR EACH. ALL OF THIS WILL HAVE A COST ON PERFORMANCE NUMBERS.

WE ARE ALL JUST SPECULATORS NO ONE KNOWS UNTIL THE FINAL NUMBERS ARE IN FROM TESTS.

I FOR ONE WOULD JUST LIKE TO GET MY HANDS ON ONE ONCE COMPLETE
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Old 9th Jul 2004, 14:28
  #46 (permalink)  
 
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BahrainLad,

Search the internet. If you know where to look you will find the info on the 747 being originally designed as a double decker.

To the rest,

It's not the function of the slide I am talking about. I am sure on they will function fine. It is the human component here that I think will be the failure point. Next time you are in a 4 story building look out the window and think to yourself....in the pitch black would I jump on a slide without hesitation from up here? Maybe you would, but the chances of at least one person freezing and blowing the test out of 200 is very high. I am not beating on Airbus's ability to design a safe airplane. It's the logic that went behind it.
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Old 9th Jul 2004, 15:15
  #47 (permalink)  
 
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Well I found this website:
http://www.flug-revue.rotor.com/FRhe...04/FR9904e.htm

In August 1965 Joseph Sutter joined the team as Chief Designer. After the program launch in March 1966 Sutter and his team looked at 50 different designs with two decks. The double-decker design was not ideal, because passengers could not be evacuated in the time prescribed by the American Aviation Authority FAA. After viewing an improvised mock up of a cabin, which was uncovered, Trippe discarded the double deck idea. The view from the improvised top deck had given almost verybody present vertigo. It is obvious why everyone involved, apart from one Pan Am pilot, refused to use the attached emergency escape slide. After this sobering experience Trippe wanted to look at the 1:1 model of a conventional single deck, which was still being constructed. This design already had the famous hump, which was to be the trade mark of the 747. It goes without saying that the hunchback attracted many sarcastic comments. It was alleged that Boeing designed the hunchback to enable wealthy captains to sit on their thick wallets and not bump their heads.

There was a practical reason for the distinctive curve. Trippe had asked for the cockpit to be situated above the cabin. This was going to make loading easier. The space behind the cockpit was allocated to the air conditioning system and other instruments. However, businessman Trippe had other ideas. "This space is reserved for passengers. Couldn't we install a bar there?" Sutter agreed with this idea, but other ideas like glass nose for first class passengers only caused everyone to shake their heads. Impressed with the size of the cabin, there were many suggestions as to how to use it, i.e. a restaurant, cinema, hairdressing salon or even a casino.
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Old 9th Jul 2004, 15:32
  #48 (permalink)  
 
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747FOCAL

If you are scared enough, you will jump with pleasure.
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Old 9th Jul 2004, 17:09
  #49 (permalink)  
 
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Cap 56,

I am going to say it one more time. We are talking about the certification test here, not actual operations.

During the test the only thing the people will be scared of is the test itself. There will be no fire, the aircraft will not be sinking or anything else that would make one want to get off in a hurry.

supercarb,

Thank you very much.

BahrainLad,

I did not mean that the 3 engine design of the 747 was original concept, just that it had been discussed. I got a lot of better pictures of it and others than that one that has been floating around the net for years.
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Old 9th Jul 2004, 18:00
  #50 (permalink)  
 
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We've got to move up to the 21st Century here. So, 40 years ago when Boeing was designing the 747, they rejected the long U/D concept because of the height. No doubt slide development was still in its infancy and they couldn't be trusted. Well here we are 40 years later with (thanks to the 747) many, many years of slide experience and development, and just as the world moved from 707 type areoplanes to 747 cabin levels, and we are flying people around with Upper Deck slides happily, the world will move to really big aeroplanes with Upper Decks and slides to handle them. It's just a question of progress, and it will happen! It's just a question of getting used to it. Airbus has made a pretty good stab at civil airliners- I trust them to have got the design and capabilities right. Why don't we just let them prove they have got it right?
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Old 9th Jul 2004, 18:05
  #51 (permalink)  
 
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Notso Fantastic,

Did you not read what I just said? I said I am not worried about the design of the slide or anything else in the design. All I am saying is that when they go to do the test I think they will have more than a bit of a challenge in getting 200 people from nearly 40 ft in the air to the ground in 90 seconds is all. It's not the airplane, it's the people. And we all know how much the French like to whine....... Or was that how much they like wine. Hey thats it, just get everybody roaring drunk and they will jump without the slide.
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Old 9th Jul 2004, 18:11
  #52 (permalink)  
 
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747FOCAL.....right on. I insist the human component is the determining factor that has most blaznely been left out of the computation. Todays world ( and yesterdays too for that matter)
is designed around profit. The more you can stick in a plane on a particular route means more money generated equal covering costs in a shorter period but thats it. When most of todays airlines show profit, it is always in a comparative manner: in actual fact there are very very few that actally make money, in other words, have something left after paying everything off to the creditors.
SAFETY has taken a third place to Efficiency, first being Economy, and some people wont admit it.
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Old 9th Jul 2004, 18:34
  #53 (permalink)  
 
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Yes I have read your message 747Focal, but it is becoming clouded in anti French/European issues that shouldn't be part of this.
I still don't see the problem. We have accepted by operating the 747-400 the concept of having people on the Upper Deck and providing them with slides from the Upper Deck. We are going to test the A380 to see if we can get 33 pairs of people out in 90 seconds from each of 3 doors- nearly 3 seconds a pair, from a similar height. 3 seconds in an emergency situation is a long time. All they have to do is jump and sit. Slides don't choke up- once you are on it it is a non-stop one way journey at the same speed for everybody. Let's leave it to Airbus to see if they can prove their hypothesis.
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Old 9th Jul 2004, 19:48
  #54 (permalink)  
 
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Notso Fantastic,

Sorry, I am not trying to be anti French/European. I was only having a bit of fun with this. In fact if I were just a tad bit younger and not with woman and child I would most certainly take a stab out of making a career in the European aviation industry. I truly love it over there. The month I spent at the RR facility at Hucknall for an RB211 engine test 2 years ago almost had me quitting and staying.

I agree, we have accepted people travelling on the upper deckof the 747 for years. It is safe. I am just trying to get everyone to think about the human factor that goes into any certification test.
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Old 9th Jul 2004, 20:22
  #55 (permalink)  
 
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The world needs the economics of large scale aeroplane operation. It is time to move over to double deckers as it cannot be achieved with single deckers. If an extra pair of doors have to be added, it is no great disaster. The French cure may well be to insist on changing the rules!
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Old 9th Jul 2004, 20:41
  #56 (permalink)  
 
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When it comes to FAR/JAR 25 you won't find many that will listen to softening the rules. I thought the JAA might give Airbus a chance at proving it by analysis, but not the FAA. Turns out they both want them to prove it can be done.

I don't know where they came up with the 90 seconds. Everybody in the business knows if the airplane is on fire you got maybe 20 seconds or the fumes from toxic burning plastic will kill you where you stand.
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Old 10th Jul 2004, 01:38
  #57 (permalink)  
 
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Roger that Toulouse. There was/were aircraft manufacturers which in the past (in the US?) allowed passengers to rehearse some part of the evac drill, or at least plan/be briefed on some part of it in advance, and I saw it on either the 'Discovery' or 'Discovery Wings' Channel. This was certainly allowed by the regulatory "authorities", to use the word authorities very loosely (other than creating and enforcing what is on legal documents)... Has this never happened with foreign companies? From what I remember, the people in the certification drill had practiced it until it was performed in the required time. Some worked for the company, and many were family members (probably more familiar with airline cabins and safety features than our typical 'local yokels') in some cabin seats. If an aircraft is sold all over the world, then it meets the requirements of all certification standards, unless built to more than one configuration etc.

My comments were not to suggest that a real-world evacuation which involves a collapsed landing gear or high winds, could only happen to an A-380. But the A-380 is the topic here, however awkward it is for Airbus staff to read certain questions or remarks. Boeing people might feel the same way about their products. It must be a very unique experience to take part in the drills and very rewarding should it happen while flying 'the line'. May God help the poor flight attendants on any plane when those people turn into a herd of panicked sheep, often rushing forwards to the main cabin door.

My concerns are not with the manufacturers, but how regulatory "authorities" can promote certain short cuts in certification of any aircraft type, not to mention many things-most having nothing to do with evacuation. One of the FAA's former mandates was to "promote aviation", while it attempted to regulate it. Bit of a conflict?

Are 'foreign' regulatory authorities never labeled 'the Tombstone Agency"?

Last edited by Ignition Override; 10th Jul 2004 at 05:55.
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Old 10th Jul 2004, 08:42
  #58 (permalink)  
 
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toxic burning plastic
?
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Old 10th Jul 2004, 09:22
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Sorry about that link Sonic Zeppelin. See here.
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Old 11th Jul 2004, 16:21
  #60 (permalink)  
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A380 pix MSN 001 flight test a/c





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