CF188A
Topic Author
Posts: 680
Joined: Sun May 07, 2006 12:27 am

A380 Media Flight (video)

Mon Feb 12, 2007 11:01 pm

Apologies if already posted under a different title. I did a search and scanned recent threads so apologies if this has been posted. I thought it was quite interesting . Nothing out of the ordinary (info wise) , for those who read these forums daily. However just being in the aircraft (video wise) , and really getting the idea of its massive structure... I thought was pretty cool. Thought I would share Smile

http://www.liveleak.com/view?i=83828b7b46
Dream as if you'll live forever. Live as if you'll die tomorrow~ RIP ... LJFM
 
racercoup
Posts: 350
Joined: Sun Jan 28, 2007 10:48 pm

RE: A380 Media Flight (video)

Mon Feb 12, 2007 11:23 pm

An interesting quote concerning that media flight.....in the International Herald Tribune.


"Richard Aboulafia, an aircraft analyst at the Teal Group in Fairfax, Virginia, said the slogan for the flight could have been, "Come see the future, as it once was." He predicted that Airbus would sell only 300 of the planes; Leahy said sales would be between 800 and 900".
 
CF188A
Topic Author
Posts: 680
Joined: Sun May 07, 2006 12:27 am

RE: A380 Media Flight (video)

Tue Feb 13, 2007 4:32 am

yes its very amusing when different stories/interpriations are compared
Dream as if you'll live forever. Live as if you'll die tomorrow~ RIP ... LJFM
 
gbfra
Posts: 427
Joined: Tue Sep 05, 2006 5:50 am

RE: A380 Media Flight (video)

Tue Feb 13, 2007 5:57 am

Well, Aboulafia was not on board. At least, I didn't see him there.

(Just for the record: Aboulafia was co-author of a very critical study of the A380, which was published in 2004. There's of course nothing wrong with critical studies in general, but there was a serious problem with this one: It was financed by Boeing.)
The fundamental things apply as time goes by
 
lostturttle
Posts: 134
Joined: Tue Dec 05, 2006 8:17 am

RE: A380 Media Flight (video)

Tue Feb 13, 2007 8:59 am

What I still find amazing is the amount of wing flex the A380 has, especially on that bumpy landing! Still, I look forward to seeing the "Whalejet" soon, and maybe even flying on it.
 
racercoup
Posts: 350
Joined: Sun Jan 28, 2007 10:48 pm

RE: A380 Media Flight (video)

Tue Feb 13, 2007 9:16 am

Quoting Gbfra (Reply 3):
Well, Aboulafia was not on board. At least, I didn't see him there.

(Just for the record: Aboulafia was co-author of a very critical study of the A380, which was published in 2004. There's of course nothing wrong with critical studies in general, but there was a serious problem with this one: It was financed by Boeing.)

Never said he was aboard........and just because Boeing financed the study doesn't mean it was distorted, most of what I've read seems to make sense. Also Airbus has changed expected sales figures and breakeven estimates so often I certainly don't trust their estimates.........
 
LASoctoberB6
Posts: 1936
Joined: Thu Nov 09, 2006 4:23 pm

RE: A380 Media Flight (video)

Tue Feb 13, 2007 10:04 am

i find it very odd that the A380 will only use two engines for reversers, not all four. it actually kinda bugs me....
[NOT IN SERVICE] {WEStJet}
 
lnglive1011yyz
Posts: 1502
Joined: Thu Oct 23, 2003 12:23 pm

RE: A380 Media Flight (video)

Tue Feb 13, 2007 12:02 pm

Quoting LASOctoberB6 (Reply 6):
i find it very odd that the A380 will only use two engines for reversers, not all four. it actually kinda bugs me....

Why?

Just because? Or....

1011yyz
Pack your bags, we're going on a sympathy trip!
 
KFLLCFII
Posts: 3177
Joined: Sat Sep 11, 2004 7:08 am

RE: A380 Media Flight (video)

Tue Feb 13, 2007 12:56 pm

Quoting Lnglive1011yyz (Reply 7):
Quoting LASOctoberB6 (Reply 6):
i find it very odd that the A380 will only use two engines for reversers, not all four. it actually kinda bugs me....

Why?

I'll answer that...For safety.

Considering that 4 out of the 20 main landing gear wheels on the A380 don't even have brakes, you would have thought they'd devise a way to utilize outboard reversers, perhaps in a manner that only blew in a certain direction to prevent FOD kick-up. (Or simply added brakes to the four remaining wheels.)

Why?

Because you've got an aircraft that is potentially heavier than a 747 on landing, utilizing the same amount of ground surface area for stopping power as the 747 (16 wheels), while only being able to use half its available thrust for reverse power (vs. the 747 being able to use all of its available thrust for reverse power). In other words, for an aircraft approximately 1/3 heavier than a fully-loaded 747 at worst-case scenario, it has less total power to stop within the same distance as the 747 does at 1/3 less weight. (Even taking into consideration the fact that the A380's engines are more powerful than the 747's, the A380 still comes away with less total reverse thrust with two engines than the 747 with four. Do the math.)

Safe?

Or only the bare minimum for certification?

You be the judge.
"About the only way to look at it, just a pity you are not POTUS KFLLCFII, seems as if we would all be better off."
 
cirrusdriver
Posts: 115
Joined: Thu Nov 23, 2006 1:29 pm

RE: A380 Media Flight (video)

Tue Feb 13, 2007 1:04 pm

Quoting CF188A (Thread starter):
Apologies if already posted

For the record, if this was a re-post, who cares? Why cant people just move along? Thank you for the video, CF188.  Wink
 
cirrusdriver
Posts: 115
Joined: Thu Nov 23, 2006 1:29 pm

RE: A380 Media Flight (video)

Tue Feb 13, 2007 1:23 pm

As far as the reverse thrust, I thought I read somewhere that the reason for the inboards only was because of how the wings would overhang the runways at some airports and kick up a massive cloud of debris. This design would allow the A380 into more airports. Very, very possible that I am only immagioning things

[Edited 2007-02-13 05:36:38]
 
WingedMigrator
Posts: 1769
Joined: Wed Oct 26, 2005 9:45 am

RE: A380 Media Flight (video)

Tue Feb 13, 2007 2:11 pm

Quoting KFLLCFII (Reply 8):
Do the math.

You might want to redo the math, this time considering that takeoff and landing speeds are about 85% that of a 747.
 
KFLLCFII
Posts: 3177
Joined: Sat Sep 11, 2004 7:08 am

RE: A380 Media Flight (video)

Tue Feb 13, 2007 3:46 pm

Quoting WingedMigrator (Reply 11):
considering that takeoff and landing speeds are about 85% that of a 747.

...To which the 747-400 has an approximately 30% greater amount of available reverse thrust for only a 15% increase in landing speed. Not to mention the fact that at max gross, it's about a third lighter than the A380.

So I ask again:

Is it safe?

Or is it only the bare minimum for certification?
"About the only way to look at it, just a pity you are not POTUS KFLLCFII, seems as if we would all be better off."
 
EI321
Posts: 4788
Joined: Tue Jul 07, 2009 4:43 pm

RE: A380 Media Flight (video)

Tue Feb 13, 2007 7:31 pm

Quoting KFLLCFII (Reply 8):
Considering that 4 out of the 20 main landing gear wheels on the A380 don't even have brakes

Maybe the A380s brakes are more powerful than those on the 747, so I needs less stopping power from the thrust reversers.

Quoting KFLLCFII (Reply 12):
...To which the 747-400 has an approximately 30% greater amount of available reverse thrust for only a 15% increase in landing speed. Not to mention the fact that at max gross, it's about a third lighter than the A380.

Now im no expert in reverse thrusters, but are you assuming the engines max power in your calculations, can thrust reversers use the engines max power?
 
KFLLCFII
Posts: 3177
Joined: Sat Sep 11, 2004 7:08 am

RE: A380 Media Flight (video)

Tue Feb 13, 2007 7:59 pm

Quote:

Taking into consideration that reverse thrust is often barely used and in some place even forbidden.

Exactly one of my original points:

Quoting KFLLCFII (Reply 8):
Or simply added brakes to the four remaining wheels.

There are 4 extra main landing gear wheels that don't utilize brakes. Why didn't they simply add the four wheels into the braking system now, rather than wait for the freighter version? Especially knowing full well that what you said is true. Sounds like they cut everything down that they could during development for the bottom line.

Quoting EI321 (Reply 14):
Quoting KFLLCFII (Reply 8):
Considering that 4 out of the 20 main landing gear wheels on the A380 don't even have brakes

Maybe the A380s brakes are more powerful than those on the 747, so I needs less stopping power from the thrust reversers.

Brakes on 16 wheels can only be so powerful until the wheels simply lock up. And that, of course, is controlled by the anti-skid system. But if you add four more wheels providing stopping power into the equation, it's that many more providing useful stopping power up until they all reach the threshold for lock-up.

Quoting EI321 (Reply 14):
Now im no expert in reverse thrusters, but are you assuming the engines max power in your calculations

No, hence why it's listed in terms of a percentage of available reverse thrust, not total thrust.

[Edited 2007-02-13 12:04:58]
"About the only way to look at it, just a pity you are not POTUS KFLLCFII, seems as if we would all be better off."
 
scouseflyer
Posts: 2165
Joined: Wed Apr 26, 2006 7:02 pm

RE: A380 Media Flight (video)

Tue Feb 13, 2007 8:46 pm

Quoting KFLLCFII (Reply 12):
To which the 747-400 has an approximately 30% greater amount of available reverse thrust for only a 15% increase in landing speed

Except isn't kinetic energy dependant on the square of the velocity?

As a very rough example we have a 1 kilo object travelling at 100 m/s (our 747) this would have a KE of

0.5 *(100*100)*1 = 5 000 J

for the "A380" say it's 1.4 times the mass of the 747 but lands at 85 m/s:

0.5*(85*85)*1.4 = 5057 J

So that's very slightly more energy with the same braking power (from the brakes) - it's not weight or speed that's important but a combination of the two....
 
User avatar
sebolino
Posts: 3495
Joined: Tue May 29, 2001 11:26 pm

RE: A380 Media Flight (video)

Tue Feb 13, 2007 8:59 pm

Quoting KFLLCFII (Reply 12):
...To which the 747-400 has an approximately 30% greater amount of available reverse thrust for only a 15% increase in landing speed. Not to mention the fact that at max gross, it's about a third lighter than the A380.

So I ask again:

Is it safe?

15% decrease in landing speed, means 28% less kinetic energy to dissipate.
 
wingman
Posts: 2793
Joined: Thu May 27, 1999 4:25 am

RE: A380 Media Flight (video)

Tue Feb 13, 2007 10:18 pm

What does a "big" hiccup look like in Europe?
 
wingman
Posts: 2793
Joined: Thu May 27, 1999 4:25 am

RE: A380 Media Flight (video)

Tue Feb 13, 2007 10:18 pm

What is a "big" hiccup for Europe?
 

Who is online