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Airbus: A380 has a weight problem

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Airbus: A380 has a weight problem

Old 7th Jul 2004, 15:26
  #21 (permalink)  
 
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Toulouse,

FAR/JAR regulations state that you can't have participated in any EVAC test in the last 6 months. And let me tell you there is nothing safe about an EVAC test regardless of who is doing it. Every EVAC test has it's injuries. From broken bones to stubbed toes. Skin burn from riding the slide down and touching your elbows. When it comes to the A380, I would bet everything I own there will be major injuries mostly from the upper deck passengers. There is a real chance that someone may die.
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Old 7th Jul 2004, 15:50
  #22 (permalink)  
 
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Exactly 747FOCAL. So you see my point. Let's just hope nobody is too injured as you seem to expect with the A380.
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Old 7th Jul 2004, 15:51
  #23 (permalink)  
 
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I am not 100 % sure, but I believe that the average weight of the Asian passenger is way below that of a European.

The A 380 is a people mover and will, in my humble opinion have a lot of success in the East even if it is a bit to heavy.
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Old 7th Jul 2004, 16:29
  #24 (permalink)  
 
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My offer to volunteer for it stands, by the way.
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Old 7th Jul 2004, 16:33
  #25 (permalink)  
 
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So its a little overweight. The launch WILL take place. What worries is the number of passengers on board trying to stay calm enough to wait their turn in line to slide down the ramp if the time comes, and it will. My God, a little investigating proves that the human equation is the weakest point in aviation evacuations. ie: Fight For Survival, Only the Strongest Survive ( yes, pushing and stepping on anything in the way, arms flaying,clenched fists punching at obstacles, even attendants trying to assist) fighting to get away from the aircraft, ME FIRST
before burning to death.
Statistics from the great manufacturers are nice in glossy form, but rewind previous accidents in smaller aircraft requiring rapid, orderly, no-time-wasting evacuations......too many pax.
This is not an attack on the 380 or Airbus, just the logistics behind its pax capacity.
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Old 7th Jul 2004, 19:56
  #26 (permalink)  
 
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This A380 Evac test thing is a complete red herring. I have been looking at the 747-400 Upper Deck slide. It is a double slide securely attached to the door, and non detachable, with large inflatable side fairings near the top. The angle is fairly shallow. In the event a 747 tipped on its tail (in the event of loss of body gear), Doors 1 slides at the front will be unuseable, but the Upper Deck slide will still be perfectly useable. In general using this slide may be slightly riskier due to the danger from its increased length of twisting (in which case don't go down it!), but I would as happily go down that as a main door slide. Now, I don't know how much higher the A380 Upper Deck slide is than a 747-400 one, but I would guess it is not much more than a few feet. So, if 747 Upper Deck door slides have been happily used and they don't have a reputation, where is the problem? I think it is a case of 'put up or shut up'. The designers know what to design for- we should let time prove they got it right.
If the designers of that waterpark in Orlando got their 'Stuka' waterslide (a seemingly near verticle drop on a concrete gutter) right, then who are we to question?
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Old 7th Jul 2004, 20:17
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Notso Fantastic,

Your comparing apples and oranges using the 747 upper deck. The 747 upper deck slide has to deal with maybe 30 at the most people while the A380 will have to deal with over 200 through 3 doors. If you do the math every person on the upper deck has to get from their seat to the door and down the slide in 1.3 seconds. Since you can't see the bottom of the slide you can't see the person that has tripped and fallen so you careen into the back of them. Right after that, the 350 heffer that was in line behind uses you as a spring board. It is going to be a real challenge to certify this thing without hurting somebody.

And your comments about the designers knowing what they are doing.... I would say they are on uncharted territory because this is the first double decker commercial aircraft of its size.
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Old 7th Jul 2004, 20:18
  #28 (permalink)  
 
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not so Mr not so.....at least not according to my books which state tail on gnd renders upperdeck slide unuseable.
I am current on type.
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Old 7th Jul 2004, 20:43
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I am generally hard to convince, but this time the weight of evidence is clearly against the A380 and it simply won't pass the evac test because it isn't a Boeing design. It's probably too heavy to fly anyway. Or too big, or too expensive, or too cheap, or too slow. Hey, here's a new twist! Why don't we start the rumor that it is too slow?

Strange how AB got it so wrong. Wouldn't hurt for some of the more well informed to let the 'Bus folks in on the secret before they waste more investor's money on it.

STL
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Old 7th Jul 2004, 20:48
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SawThe Light,

Never said it was because of not being a Boeing design.

Originally, the 747 was supposed to be a double decker like the A380, but their sumulations made them think they would be unable to satisfy PAX EVAC tests so the shortened deck came about. Interestingly enough, they did not know that much about area ruling and had no idea that the hump would make the airplane perform in cruise better than without the hump.
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Old 7th Jul 2004, 21:12
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Fire Wall- I can categorically state ALL 57 British Airways 747-400s have Upper Deck Slides which are useable in the event of tail on ground. Only Door 1 slides will then be unuseable. I am current on the 400 and did my annual safety training today and specifically confirmed this point.

Where does this absurd figure of 1.3 seconds to leave seat and evacuate come from? When in the door, you can see the whole slide and who is on it. In a horizontal attitude, the angle of the slide is shallower than the other slides to cope with the tail on ground situation. If it is OK for the 747-400, how is it not acceptable for the A380? The A380 is the same, just a little bit taller- if it is OK for the 747, it is OK for the A380.
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Old 7th Jul 2004, 23:54
  #32 (permalink)  
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The 747 started life as a cargo plane, and never had anything to do with pax evac tests. The 747 was always designed from the outset as only having a short upper deck - never full length. The reason was to move the cockpit up high so cargo could be loaded through the nose. It was the competition to the C-5 Galaxy. When Boeing lost the competition - they turned it into a passenger plane.
 
Old 8th Jul 2004, 00:35
  #33 (permalink)  

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Yup, given the existing airframe the upper deck could never have gone all the way to the tail.
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Old 8th Jul 2004, 13:47
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Not so....I am at a loss to explain this discrepency between yours and my documentation. I shall investigate further.
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Old 8th Jul 2004, 14:15
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The BA 747-400 Tech Manual states: "If both Body Gear are not extended, the aircraft may tip tail down on the ground. Door 1 escape slides are then unusable". At my annual Safety Equipment Procedures Test this week, I specifically queried this point and was assured the Upper Deck slides would still be usable. The practice computer exam also confirms this.
I wonder if there are options when you order the equipment for a 747 as to the standard of the sliderafts? Like on the order form:
Car Stereo....Yes/No
IFE Crew bunks.....Yes/No
Extended U/D Door Slide......Yes/No
etc!
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Old 8th Jul 2004, 16:34
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Skyhawk1:

The 747 started life as a cargo plane, and never had anything to do with pax evac tests. The 747 was always designed from the outset as only having a short upper deck - never full length. The reason was to move the cockpit up high so cargo could be loaded through the nose. It was the competition to the C-5 Galaxy. When Boeing lost the competition - they turned it into a passenger plane.
Not exactly right. There clearly is some influence from the C-5 proposal and some sharing of engineering talent but the aircraft are quite different. The main difference was the C-5 proposal had a high wing instead of a mid wing, and had landing gear and performance suited to landing on shorter, less developed airfields.

Clearly after the loss of the C-5 competition Boeing knew a large transport was feasible and also that they had the talent to produce it. But the design is really quite different.

As you probably know, the reason the 747 retained the attributes of a cargo aircraft (including the ability to load cargo through the nose) was Boeing believed that supersonic passenger planes would be available in a few more years and they needed a role for the 747 to perform once it was retired from passenger service.

--ev--
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Old 8th Jul 2004, 17:38
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Notso Fantastic,

If you read around Airbus has already stated that the upper part of the slides on the upper deck of the A380 have a horizon shield so that the person jumping cannot tell how high off the ground they really are. You also cannot see the bottom of the slide. Their words not mine.

The 1.3 seconds is derived by using the cert requirements (half the upper doors) which is 3 doors. 200 divided by 3 equals 66.67 persons per door. You then divide 90 seconds by 66.67 people to get 1.3 seconds per person. This is very conservative as none of the people in the test including the crew no which three doors will be unusable until they open them. It also does not take into account the amount of time necessary to extend the slides. I suppose they could get lucky and only open the doors that are not blocked off. It is also pitch black with only emergency lighting so you are asking 200 people to blindly jump into a black hole and hope to god they don't get hurt. The problem is, these people know there is no emergency and the only danger they are in is from the test itself.

Rollingthunder,

The airframe design changed when the upper deck was shortened. I have many pictures of the concept airplane models. I also have pictures of the 747 with two engines on wing and one in the tail. The wood model still exists and is not far from my desk.


skyhawk1,

Why would anyone design a plane with only one use intended and cut themselves off from the rest of the market? Nobody is that stupid. The 747 was always intended to enter both the military market and the passenger market. Just like the C-17 will eventually enter the commercial cargo market as the BC-17.

I wish I could post the pictures and the documentation from when the 747 was first thought up, but alas they hang people for that in the USA.

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Old 8th Jul 2004, 23:09
  #38 (permalink)  

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Just do it here 747FOCAL, we won't tell!
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Old 9th Jul 2004, 00:06
  #39 (permalink)  
 
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747Focal- your sums are not quite right. The slides will be double lane, so they will go off 2 by 2 like animals entering the Arc, not one at a time. 67 people per door, 33 pairs in 90 seconds- with their asses on fire? They'll get off! Better in the dark, can't see the drop.
I'm sure Airbus have done their sums, and I cannot see what is wrong.
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Old 9th Jul 2004, 03:14
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Notso Fantastic,

So why is Airbus so worried about it themselves? They made application to both the JAA and the FAA to do it totally by analysis and not perform an actual test. They were told no by both so now they have to really do it.

Their ass won't be on fire and all it will take is one that freezes and won't jump and then they have to get another 200 people and crew to do the test or wait 6 months to do it again.

When they go to do the Asian seating style there will be way more than 200 up there.

ps. going 2 by 2 is only going to make the chance that a screw up occurs only greater. I did not know it was a double slide though. All the simulation I have seen it was a single slide.
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