A380

[westwing]

Just a thought looked at many photos of the A380 after landing, are the flight test aircraft operating with reverse on the inboards only. can any one tell me why this is please

[Old Aero Guy]

That's because on the A380, only the inboard engines have reversers.

There are no reversers on the outboard engines.

[Fish Out of Water]

Another glitch - what a great a/c. The 748 will skin it alive! The question is where are the planes going to go to when more cancel the orders! Vive la boeing :ok:

[surely not]

If it was planned only to have thrust reversers on the inboard engines how does this constitute a glitch Fish out of Water?

Don't let your love affair with Boeing cloud your thought patterns. Why will the 747-800 be so great? It is warmed over old technology isn't it?

[GEnxsux]

The CAA forced reversers on the inboards. Airbus wanted to go completely on brakes.

What a glitch!! More like an advancement in technology & less noise. Goof.

[Fish Out of Water]

If the things so great then why is opinion on it changing so much? Not knocking the bus by any means, think the 340-500 is pretty much the most underrated a/c out there, overshadowed by the enlarged beluga! How is it so ugly when the 330's so good looking - probably couldn't stand the peer pressure and gouged itself on chocolate instead!

[Fernando_Covas]

Isn't it a design feature? Because of the wingspan, reversers on the outer engines will just blow muck and crap forwards to be re-ingested.....

[Richard Spandit]

On the Boeing 757/767, the thrust reversers don't slow you down any quicker than the autobrakes - they just allow the brakes to work less hard. If Airbus have designed the brakes so that you don't need to take the load off with thrust reversal, then the lack of it isn't a worry. The chance of a complete brake failure is pretty remote in my opinion, and that's knowing nothing about the A380.

[False Capture]

We rarely use any more than reverse-idle on the B777. Exceptions being:
i) landings on contaminated or slippery runways
ii) RTOs above 80kts

[wingman863]

It will be very interesting to see how events unfold and whether or not the A380 achieves success and if so, to what degree; possibly becomming as common as the 747 series is now; I'd say this is unlikely though.

[vapilot2004]

Airlines insisted on having reversers available. Fernando_Covas has the info correct on why the outboard mills don't have them.

Come on now - give big bird a chance. Let's see what happens when she enters revenue service.

It will be interesting to see the real numbers and the relationship to the Boeing VS Airbus PR spin on economics. Boeing states that the re-engined and stretched 748 will be cheaper to operate per seat mile than the A380. :hmm:

[cap10lobo]

I have +3000h on 340 by now and I´m still amazed over how simple and reliable this AC is, best i´ve flown so far.
Whatever airbus constructed it´s probably quite well thought through. And they´ve probably forced boeing to shape up.. The 767 was sooo boring:}

[jondc9]

how quickly we forget...reversers out and working properly and on time for that southwest at midway would have been helpful.

inboards are better than nothing

[ChrisVJ]

Not a heavy pilot but I would have thought that inboard engines in reverse thrust would be more likely to throw stuff into the outboard than vice versa. If there is a structural or aerodynamic reason for inboard only I would think it would have to do with the lateral moments of one outer engine failing to deploy.

Again, as a mere customer I wonder what happens when the tarmac is icy and you are relying on brakes only to stop ' how many tons?'

[vapilot2004]

Not a heavy pilot but I would have thought that inboard engines in reverse thrust would be more likely to throw stuff into the outboard than vice versa. If there is a structural or aerodynamic reason for inboard only I would think it would have to do with the lateral moments of one outer engine failing to deploy.


Unlike #2 and #3, the outboard engines will not be over tarmac (or very nearthe edge) at many airports during rollout - hence the increased chance of FOD from the unpaved area. With regard to FOD due to reversers, the engine ingests it's own wash.

[ARINC]

I can't help myself...

Check out this video I uploaded

http://video.google.com/videoplay?docid=-3046542226114078023

I love boeings..but lacking spiral staircases, oh and neat ideas like vertical profile displays, I think they've slipped behind. Just my completely subjective point of view you understand.

[Sqwak7700]

Does anyone know what those doors are under the inboard leading edges of the wings, close to the fuselage? I thought I had heard that the packs are in the wings, so maybe they are pack inlet doors? :confused:

Sq.

[Fish Out of Water]

The engines are pretty much at the same level with the amount of droop in the wing! Might have something to do with the 50t they took off the MTOW. Good plane though, hmm....

[Sqwak7700]

The CAA forced reversers on the inboards. Airbus wanted to go completely on brakes.

What a glitch!! More like an advancement in technology & less noise. Goof.


...Obviously you have never landed on a snow covered runway that was reported to have "good braking action". Or been the first to land on a chemically de-iced runway, completely cleared of contaminants...except the one the airport put on it. :ugh:

Brakes are great until there is "no braking", then they are just more weight to help you go off the end of the runway a little faster.

Excellent brakes are a nice thing to have. I used to love the Embraer's great big carbon discs. You could stop that plane on a dime, to the delight of LGA nad DCA ATC. :E

Mind you, reversers wont stop an airplane. But they might make the difference between going all the way out of the airport property or just ending up on the grass at the end of the runway. Especially on a big airplane with long runway requirements.

It will take more than a gas station or a poor motorist to stop this thing if it goes off-roading after an overrun. :uhoh:

[Zeke]

Another glitch - what a great a/c. The 748 will skin it alive! The question is where are the planes going to go to when more cancel the orders! Vive la boeing :ok:

You did realise the 380 will touch down at 138kt, much the same speed as a 320, where the 748 will be 160+ like a 777.

Don't let your love affair with Boeing cloud your thought patterns. Why will the 747-800 be so great? It is warmed over old technology isn't it?

They have seen the light, the 748 will now be FBW as well.

[cap10lobo]

Reversers are only effective at high speeds and are generally stowed at aprox 80-60 kts. A380 probably dont land at higher speeds than other heavy jets but will most likely only operate the largest airports in the world. That means verry long rwys and most often wide(60m). If you are not able to stop on a 3700m+ RWY due to poor BA, there are far more severe problems to deal with, like x-wind..

And I do operate on snowy RWY´s :ok:

[False Capture]

You did realise the 380 will touch down at 138kt, much the same speed as a 320, where the 748 will be 160+ like a 777.
You didn't realise that the touchdown speed of a B777-200 at maximum landing weight and full flap is 138kts.

[swh]

False Capture,

Where did it say 777-200.

:mad: Lame boeing driver :p

[Fish Out of Water]

Still, one thing's for certain - it's not exactly a looker! Reminds me of some northern birds on a night out, lots of flesh on show and wedged into a miniskirt :yuk:

[vapilot2004]

how quickly we forget...reversers out and working properly and on time for that southwest at midway would have been helpful.


Perhaps less of a tailwind gust and a properly cleared runway or at least an honest and recent braking action report on said runway beforehand would have made the reversers a non-issue as they should have been.

If we are depending on the relatively meager stopping force of reverse thrust to make or break (should I say brake....) the landing,maybe the entire exercise should be re-thought.


Still, one thing's for certain - it's not exactly a looker! Reminds me of some northern birds on a night out, lots of flesh on show and wedged into a miniskirt

I thought the same until I saw this . . . . hmmm - help me out someone, I know I have spied a lovely angle on this bird in SA paint........ 'quite beautiful as I recall..'

[Old Aero Guy]

You did realise the 380 will touch down at 138kt, much the same speed as a 320, where the 748 will be 160+ like a 777.
They have seen the light, the 748 will now be FBW as well.

Tell what version of the 777 has a 160+ kt. Vapp. The manuals I have all say that at MLW, Vapp is 150 kt or less.

[Fropilot]

Most pilots act like they own the Airbus or Boeing aeroplanes they fly and some seem to have serious issues with one manufacturer or the other.

What you need as a pro pilot is a safe aeroplane to fly and away from any likes or dislikes one may have is what aeroplane will make money for your airline-period. You are hired to fly whatever is available. Make sense????

[Packsonflight]

The "new" 748 is starting to sound more and more like the 745&746 boeing offered years back, and nobody wanted to buy.
with new engines, systems and wing, it is going to cost a lot of money to develop. the cost could aproach half the cost of the A380 program and still they are offering the old airframe!!! does not make sense to me.

[Volume]

Sqwak7700 : Does anyone know what those doors are under the inboard leading edges of the wings, close to the fuselage? I thought I had heard that the packs are in the wings, so maybe they are pack inlet doors?
These doors are the Airconditioning pack outlets, the intake is via the large NACA-slyle inlets in the belly fairing.
left outflow doors closed, right doors opened, same for the inlets (http://www.planepictures.net/netshow.php?id=448105)
Moving the packs to the wing and kinking the wings front spar backwards enlarges the front cargo hold significantly. This is quite important for an airplane having two decks with passengers and just one for their luggage...

[Fropilot]

The "new" 748 is starting to sound more and more like the 745&746 boeing offered years back, and nobody wanted to buy.
with new engines, systems and wing, it is going to cost a lot of money to develop. the cost could aproach half the cost of the A380 program and still they are offering the old airframe!!! does not make sense to me.

Quote from airbus goes along these lines,

This is the first time that a civil aircraft program is going to be launched on the back of cargo aircraft orders/requirements

[Check Airman]

You didn't realise that the touchdown speed of a B777-200 at maximum landing weight and full flap is 138kts.

That's amazing!!! Better than the 763 or 744. What's the speed at minimum weight?

[merlin505]

I believe that the number of thrust reversers has a lesser effect on landing roll distance as it is increased. For a simplified model of a 4-engined aircraft under poor runway conditions (ice/snow) the reduction in landing roll length for 2 thrust reversers is approx.30-40% but increasing the number of thrust reversers from 2 to 4 results in only a further 10% reduction. If weight or other factors are critical then getting rid of two of your thrust reversers does not present such a big landing performance degrade. I believe the VC-10 was originally designed with 4 reversers but then dropped to two after it was found that in service the stopping performance of two was satisfactory.
As previously stated by another poster i think the most likely reason for selecting to keep the reversers on the inboard engines is to minimise lateral moments should one reverser fail.

[Fropilot]

As previously stated by another poster i think the most likely reason for selecting to keep the reversers on the inboard engines is to minimise lateral moments should one reverser fail.[/QUOTE]

This is a valid point. From experience on the B707 and DC 8 we normally used only the inboard reversers. However we used to deploy all the four reversers but used idle reverse on the outboards and up to full reverse on the inboards. The reason for deploying all four was that in case there was an inboard reverser failure and stopping became a problem then full reverse was available on the outboards.

[Roadtrip]

Well, at least th 380 saved the weight of the outboard reversers, since the aircraft is overweight already.

We'll see how it does in service. Maybe it will garner a few more orders if it does well. It'll make a great hajj cattlecar. But, Airbus has sunk a lot of money into the thing. Don't they have a breakeven point of something like 350 aircraft, and so far it's way short of that in any kind of orders.

The A340s? The 777 has far outsold the 340. The A350 is coming into the niche way later than the 787.

Maybe Airbus can snuggle-up to the Arab sheiks and get some more orders.

[Grunf]

Packsonflight, Fropilot;

It should be very creative to come up with such development costs that would bring a cost of derivative close to cost of a new project. Ratio is much closer to 1:10.

Even if you want to be conservative you go with 20% which is really high. Assuming that some of the cost will be offset to 787 work already done it is not surprising that Boeing is trying to spread the new stuff to its current programs.

747 is the logical example since it has the good capacity and fact that they sold cargo prior to passenger does not mean it is carried by the cargo version.

it is simply question of who reacted first, in this case. Cargo a/c are seeing boom in the last few years so there is a lot more demand form them then for pax a/c.

Cheers,

[moggiee]

Another glitch - what a great a/c. The 748 will skin it alive! The question is where are the planes going to go to when more cancel the orders! Vive la boeing :ok:
B777 only has reverse on the inboards, too.

Yes, I know it only has two engines - thus making the point that if you only need it on two, only fit it on two.

Protoype VC10s had four reversers - tests proved that only two were needed so that's all the production model got.

One advantage of fitting it to the inboards is that there will be smaller yawing moments in the advent of an asymmetry.

[moggiee]

Don't they have a breakeven point of something like 350 aircraft, and so far it's way short of that in any kind of orders.
I thought that they said 150.

Still, Boeing fans can content themselves with the thought that, like the 300, 310, 320 and 330 it will be a flop!

[Check Airman]

I still think the 380 should have all 4 reversers. The bean-counters let money blind them sometimes. The minimal drag effect of the 2 outboards (assuming it's accurate data) is still batter than none at all.

What's cheaper, replacing 2 outboards because of FOD, or replacing the plane after it runs off the runway and into the water?

[lomapaseo]

I still think the 380 should have all 4 reversers. The bean-counters let money blind them sometimes. The minimal drag effect of the 2 outboards (assuming it's accurate data) is still batter than none at all.

What's cheaper, replacing 2 outboards because of FOD, or replacing the plane after it runs off the runway and into the water?


I guarantee you that there will be less planes off the runways into ditches by leaving off the outboard reversers.

[CV880]

I am not sure about the CAA requiring reversers as suggested by GEnxsus. I attended a number of the early A3XX working groups (before it became the A380) for my then employer in the late 90's and the reverser issue was raised by Airbus.
As others stated Airbus preferred the no reverser option to save weight and complexity and maintenance costs plus there were so many wheels that could be braked however the airline working group recommended Airbus go with the inboard reverser option. The reason was, if I recall correctly, in one scenario put forward by Airbus the required runway length was very long thus possibly preventing a max gross weight TO on a wet/slippery runway at some airports.