GRIVely
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Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 6:44 am

Last summer I was on business in Europe with the president of my company. We both left FRA for IAD about the same time. He was on a UA B777 and I was on an LH A340 (might have been a 400, not sure). I was in business on the right side just in front of the wing. As we were crossing the Irish coast arcing over onto the great circle route I noticed another aircraft coming up beside us on the right.

It pulled level with us and I could see it was a UA 777. We flew in companionable silence for a few minutes and then it started pulling away from us, not too quickly, but very steadily and in less than 10 minutes was completely out of my line of sight.

On the ground in IAD I linked up with my colleague and we discovered that was his 777 and he had seen the A340 from his left side seat. He landed at IAD about 40 minutes before I did so he had a coffee and read the paper while waiting for me.

What is there about the 777 that makes it that much faster than the A340?

Thanks in advance for any illumination.
 
ikramerica
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 6:50 am

Short answer: Boeing designed it to be faster, nearly as fast as the 747, so it was more interchangeable in the scheduling. It also means that for certain routes, one 777 can do the route daily, but it would require 1+ A340s.

Airbus knows this is a severe disadvantage, and I am sure customers have told them so, because both the A380 and A350 have been designed to fly faster. But flying faster has an effect on fuel efficiency in cruise.

The fact that the 777LR series is faster, more efficient and more reliable than the A340NG was the triple win that broke the A340s, back. Had the A340 had the clear advantage in any of those categories, sales would not have dropped off the cliff like they did.
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beech19
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 6:53 am

Quoting Ikramerica (Reply 1):
Airbus knows this is a severe disadvantage, and I am sure customers have told them so, because both the A380 and A350 have been designed to fly faster. But flying faster has an effect on fuel efficiency in cruise.

The crazy part is... the 747 will STILL be the fastest commercial aircraft in the world. And the 748 will be Mach .005 faster than the 744.
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Arsenal@LHR
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 6:55 am

The simple answer is that the 777 has a higher cruise speed than the A340 (all models) Mach 0.84 i believe versus the A340-300's Mach 0.82. Other factors such as aerodynamics and wing design have a lot of bearing on speed. A340's have four engines which i assume increases drag more than a twin such as the T7. The higher thrust rating on 777's wings than the A340's might make a difference in speed although someone correct me if i'm wrong.
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ikramerica
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 6:59 am

On a recent 744 flight, we flew mach .89 the whole way to make up for a 2 hour delay and a curfew on the other end. The fact we had 100 or so pax didn't hurt the cause, either.

The A380 should be able to do that too, but no other Airbus plane can do that right now. Not even close. The T7 can almost sustain that, but I am not sure about the first half of the flight when it is swollen with fuel...
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Ari
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 7:03 am

I remember travelling at +1000kmh on an SQ B772. I think it was around 1052ish but cant be sure but we had a hell of a tailwind!!

aRi
 
kiwiandrew

RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 7:04 am

Quoting GRIVely (Thread starter):
He was on a UA B777 and I was on an LH A340 (might have been a 400, not sure).

an A340-400 ??? -200/-300/-500/-600 sure , but I have never heard of an A340-400
 
SNATH
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 7:05 am

Quoting GRIVely (Thread starter):
(might have been a 400, not sure)

First, welcome to the "family"! LH's A340 was most likely a -300. FYI, the A340 has no -400 submodel.

Quoting Beech19 (Reply 2):
The crazy part is... the 747 will STILL be the fastest commercial aircraft in the world. And the 748 will be Mach .005 faster than the 744.

Here's an interesting data point. I've flown BOS-FRA on LH many times in the past. I've done it on both B747s and A340s. They have slightly changed the times now, but a couple of years ago the early flight was scheduled for 430pm for a 530am arrival if it was an A343. When, during the winter they switched to a B744, they departure time was moved to 445pm for the same arrival (530am). It was pretty cool, as I could guess what type of plane it'd be just be looking at the departure time!  Smile

Quoting GRIVely (Thread starter):
and then it started pulling away from us, not too quickly,

One of the coolest things I've seen while flying was when I was doing GLA-YYZ on an AC B767. I was reading a book and suddenly something caught me eye outside. I looked and it was a NW B774 passing us slightly below us. It overtook us so fast, that I only had the time to snap two pictures before it disappeared "into the distance"... I was quite impressed!

Tony
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cobra27
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 7:18 am

Quoting GRIVely (Thread starter):
What is there about the 777 that makes it that much faster than the A340?

The speed advantage is only 0.02-0.04 Mach. Not much really
 
gigneil
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 7:21 am

Quoting Beech19 (Reply 2):

The crazy part is... the 747 will STILL be the fastest commercial aircraft in the world. And the 748 will be Mach .005 faster than the 744.

The A380 will cruise at M0.86, which is faster than the 744's standard cruise.

The A380 also has a sprint cruise of M0.89, like the 744 and 748.

For all intents and purposes, they are both fast.

NS
 
beech19
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 7:24 am

Quoting Cobra27 (Reply 8):
The speed advantage is only 0.02-0.04 Mach. Not much really

That turns into to a half hour of flight time on a very long flights of 7000nm+. Thats over and over every day. That is a lot of extra potention flight time and any time you can cut a super long flight shorter, you do.
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ikramerica
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 7:27 am

Quoting Cobra27 (Reply 8):
The speed advantage is only 0.02-0.04 Mach. Not much really

That's 30 minutes on a long haul flight. Can mean the difference between getting in 1 turn a day, or less.

There was a reason Boeing was pushing the Sonic Cruiser when fuel was cheap. Fixed costs would be drastically lower as fewer jets would be needed in a fleet. Also, routes that required 2 crew rotations in flight could be pared to a single crew in some cases. Of course, that was more than 0.02 mach, but that was the point. And airlines had major interest until 9/11 and then the price of oil...

Quoting Gigneil (Reply 9):
The A380 will cruise at M0.86, which is faster than the 744's standard cruise.

I thought it had been paired back to 0.855, which is what the 748i is also listed as.
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jogales
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 9:01 am

Quoting GRIVely (Thread starter):
What is there about the 777 that makes it that much faster than the A340?

You tell me Big grin

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legoguy
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 9:12 am

Quoting SNATH (Reply 7):
NW B774

Presume you mean 747  Silly

Since the a340 has wings with less sweep, does this give better low speed handling?
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JAL
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 9:27 am

Wow!!! Didn't know that the 777 was that faster than the A340!
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antskip
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 9:29 am

Quoting Ari (Reply 5):
remember travelling at +1000kmh on an SQ B772. I think it was around 1052ish but cant be sure but we had a hell of a tailwind!!

Aircraft fly within air, not on the ground. If +1000kmh was ground speed, it is just a record of speed relative to the ground - made up of the sum total of vehicular speed and local air movement. A plane flying at 100 kmh into a 100 kmh head wind would be not moving at all, relative to the ground. With a 100 kmh tail wind, it would be flying at 200 kmh relative to the ground, though the vehicle's air speed is unchanged.
 
gigneil
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 9:32 am

Quoting Legoguy (Reply 13):
Since the a340 has wings with less sweep, does this give better low speed handling?

Absolutely. Its a philosophical difference.

Airbus' wings are optimized to provide more lift but less speed, which is why both the A330 and the A340 fly with much less installed thrust than their Boeing counterparts.

Boeing installs more thrust to get the plane in the air, then they scream through the sky.

Quoting LHR777 (Reply 14):
Based on the above pictures - one has two engines, the other has four hair-dryers........

Nothing even remotely at all to do with it.

NS
 
SNATH
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 10:16 am

Quoting Legoguy (Reply 13):
Presume you mean 747

Nah, it's a new designation for a B747 with a DC-9 body bolted onto it to extend its capacity...  Smile

Tony
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flydreamliner
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 11:00 am

Quoting Ikramerica (Reply 4):
The A380 should be able to do that too, but no other Airbus plane can do that right now. Not even close. The T7 can almost sustain that, but I am not sure about the first half of the flight when it is swollen with fuel...

The 747 will still have a faster sprint speed than the A380, with 747-8 being able to do a max cruise of .89, and a max mach number of .92, as compared to a max mach on .89 on A380, but only by a shade, they'll cruise pretty close to each other. The 777 can run at near 747 cruise, but again, lacks 747's full sprint ability. The 787 will cruise at roughly 748 speeds, though its sprint capabilities are yet to be seen.

Quoting Gigneil (Reply 9):

The A380 will cruise at M0.86, which is faster than the 744's standard cruise.

Will it be .86 or .85....

Quoting Gigneil (Reply 18):
Airbus' wings are optimized to provide more lift but less speed, which is why both the A330 and the A340 fly with much less installed thrust than their Boeing counterparts.

Much less? the A343 has a real fight to get in the air fully loaded. A346IGW actually has more thrust on it than 773ER, then again 773ER has a lower empty weight (allowing it to carry more payload and burn less fuel doing it).

The big thing that impacts speed is the wing. The airbus wing is intended for a more conservative layout, giving more low altitude lift, at the cost of top speed... also, less swept wings end up being lighter more often.

In order to fit more wing into a smaller span, the 747 used a 37.5 degree sweep, which translated into a higher cruising speed. The 777's sweep is somewhat similar to that in A340, moreso A345/346, however, A380 uses a 33.5 degree wing,
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GRIVely
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 11:25 am

Thank you everyone for the most thoughtful replies and the cogent illumination of the issues. (Note attempt to measure up to the high standards of the A.netters. Well, most of the crew anyway.)

Ta.
 
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 11:39 am

Even the almost 50-year-old 707 and DC-8 is faster than the A330/340. The 707 is marginally faster than the DC-8, largely due to the 707's slightly greater wing speep angle (same as the 747 if not mistaken), but the difference between the 707 and DC-8 speed is much smaller than between a 747/777 and A330/340. As has been mentioned by others, that can easily make a difference of 30 to 45 minutes on long sectors of 10 or 12 hours.

The DC-10/MD-11 are also faster than the 330/340 (and 300/310).
 
ikramerica
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 12:39 pm

Quoting Gigneil (Reply 18):
Boeing installs more thrust to get the plane in the air, then they scream through the sky.

That is not really true when comparing the 343 to the 772 or the 346 to the 773.

As twins, the 777 must have more installed thrust because with one engine out, a single engine must have enough thrust to continue takeoff, keep the plane aloft and safely land.

On the 77W, that's 115k. The 346 must have enough thrust so that 3 engines can do that. On the 346, that is 168k pounds. Well, the 346 likely needs less than 168k to do this, but since 2 engines produce 112k, the number is somewhere between 112k and 168k. But this example shows the A340 requires MORE installed thrust on an engine out basis than does the 777, which is one measure of which frame is more efficient.

On the 343, the highest thrust version has 34k engines, so engine out thrust is 102k, which is again higher than the thrust on any 772ER engine available (IIRC, the most powerful 772ER engine is 94k)...
Of all the things to worry about... the Wookie has no pants.
 
mbj2000
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 7:28 pm

Quoting FlyDreamliner (Reply 20):
Much less? the A343 has a real fight to get in the air fully loaded. A346IGW actually has more thrust on it than 773ER, then again 773ER has a lower empty weight (allowing it to carry more payload and burn less fuel doing it).

The big thing that impacts speed is the wing. The airbus wing is intended for a more conservative layout, giving more low altitude lift, at the cost of top speed... also, less swept wings end up being lighter more often.

In order to fit more wing into a smaller span, the 747 used a 37.5 degree sweep, which translated into a higher cruising speed. The 777's sweep is somewhat similar to that in A340, moreso A345/346, however, A380 uses a 33.5 degree wing,

Interesting numbers, I wonder how Airbus managed to keep the less swept wings and still reach a higher cruising speed for the A380? Just by using more thrust at the expense of higher fuel burn?
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LHR777
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 7:53 pm

Quoting Gigneil (Reply 18):
Nothing even remotely at all to do with it.

No, really? Thanks for that clarification....  Yeah sure

..now back to more serious matters, as having a bit of a laugh is obviously frowned upon......
 
keesje
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 8:00 pm

I think "the 777 beat the A340" kind of topic is on the brink off taking over the "when will NWA replace their DC9s" topics / open questions..

It even get endlessly referred too by many members irrespective off the running topic. And not only on a.net.

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acidradio
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 8:07 pm

Quoting Keesje (Reply 26):
I think "the 777 beat the A340" kind of topic is on the brink off taking over the "when will NWA replace their DC9s" topics / open questions..

Will that happen when they actually replace their DC9's?
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zeke
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 8:25 pm

The difference is in engineering, nothing more. Airbus went to the airlines and they were happy with the 340 cruise speed before it went into final design.

It has very little to do with powerplants, engines do not produce that much thrust at altitude.

The main factor which effects where you can efficiently cruise is the wing sweep angle, it reduces the critical mach number and the overall wave drag.

The 777 it is at 31.6 degrees, 29.7 for the 342/343 and 31 degrees for the 345/346.

The 744 is 37.5 degrees and the 380 is 33.5 degrees, which should generally mean that the 747 would have a higher cruise, however the 380 has a more advanced transonic wing which reduces its wave drag.
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Rj111
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 9:01 pm

Quoting Ikramerica (Reply 21):
On the 343, the highest thrust version has 34k engines, so engine out thrust is 102k, which is again higher than the thrust on any 772ER engine available (IIRC, the most powerful 772ER engine is 94k)...

You have assumed that the A340 has chosen the bare minimal power to take off on 3 engines. In reality this usually is untrue for a quad as it would result in a severely underpowered aircraft which would be inefficient. The twin may well have the bare minimal for take off on 1, any higher and the aircraft could be overpowered in normal service which would once again reduced efficiency.

As for the orignal topic.

Remember the lift formula...

L = (1/2) d v^2 s CL

L = Lift
d = Air density
v = Velocity
s = Wing area
CL = Coefficient of lift (factor of aerofoil shape and angle of attack)

It's true, Airbus's designs often make the wing do the work through either CL and s, whereas Boeing boost the v to give a similar lift.
 
keesje
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 9:12 pm

Quoting Zeke (Reply 26):
Zeke

 checkmark 

On the otherside having a "fast" wing also leads to it being fast during landing take-off. E.g. the 747 has a much higher landing / take-off speed and a heavy & complicated flap system.

http://www.theairlinehub.com/uploads/Undercarriage.b747.arp.jpg

It's always a trade-off. The 737NG got less sweep then the -300/400.
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zeke
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 9:39 pm

Quoting FlyDreamliner (Reply 18):
Much less? the A343 has a real fight to get in the air fully loaded. A346IGW actually has more thrust on it than 773ER, then again 773ER has a lower empty weight (allowing it to carry more payload and burn less fuel doing it).

1...The 346 has 67436lb less thrust on it the the 773ER, you are looking at the 5 min takeoff rating, not the max sea level (773ER =110000x2 and 346 = 44359x4)

2..At MTOW 343 will use less runway than a 744/764/773/773ER at MTOW, and will out climb a 744 to 10000 ft.
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autothrust
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 10:03 pm

Quoting FlyDreamliner (Reply 18):
In order to fit more wing into a smaller span, the 747 used a 37.5 degree sweep, which translated into a higher cruising speed. The 777's sweep is somewhat similar to that in A340, moreso A345/346, however, A380 uses a 33.5 degree wing,

From all this posts i can assume Airbus did a very good job with the A380 wing. It can cruise at 0,89 and the A380 needs less runway for takeoff and landing then the 747. Lower landing speed is always a gain in security.

I wonder wich angle the 748 wing will get and how will the landing performance might be?
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Aviator27
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 10:55 pm

The short simple answer to your question is design. Boeing and Airbus had different long range airplane strategy. Boeing wanted faster and more efficient. Airbus wanted economical cruise and more efficient. Remember drag is the square of your airspeed. So if your speed doubles, your drag, and subsequently power required quadruples. For a while, Airbus won with its strategy. Then Boeing designed the B77W with a better wing to be as fast, but even more efficient.

The customers did speak and Airbus did listen. The A350XWB will cruise at Mach 0.85.
 
OldAeroGuy
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 11:02 pm

To approach this discussion in parts, why is an A333 (LRC@0.82M) faster than a A343 (LRC@0.81M)?
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lightsaber
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 11:33 pm

Quoting Zeke (Reply 26):
The main factor which effects where you can efficiently cruise is the wing sweep angle, it reduces the critical mach number and the overall wave drag.

The 777 it is at 31.6 degrees, 29.7 for the 342/343 and 31 degrees for the 345/346.

The 744 is 37.5 degrees and the 380 is 33.5 degrees, which should generally mean that the 747 would have a higher cruise, however the 380 has a more advanced transonic wing which reduces its wave drag.

Nice summary. Thank you.

Quoting Keesje (Reply 28):
E.g. the 747 has a much higher landing / take-off speed and a heavy & complicated flap system.

It will be interesting to see how the 748 modifies the flaps. Yes, the modification is mostly for noise (QC2 compliance), but it would shock me if weight wasn't removed.

Quoting Acidradio (Reply 25):
Will that happen when they actually replace their DC9's?

Blasphamy!  flamed   flamed   flamed 

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CHRISBA777ER
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RE: Why Is A B777 Faster Than An A340

Thu Dec 21, 2006 11:53 pm

Quoting Zeke (Reply 29):
At MTOW 343 will use less runway than a 744/764/773/773ER at MTOW, and will out climb a 744 to 10000 ft.

I have to say thats pretty incredible. Thus is another a-net myth debunked.
What do you mean you dont have any bourbon? Do you know how far it is to Houston? What kind of airline is this???
 
PlainSmart
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RE: Why Is A B777 Faster Than An A340

Fri Dec 22, 2006 12:24 am

Has anyone mentioned cost index? Cost index is a value entered into the FMS that calculates the the speeds to be flown. This is dependant on fuel, delays, flight time, specific crew pay, etc. I believe the dispatcher/company assigns this value. Maybe the 777 crew was a bunch of private pilots flying for free, haha.
 
xv408
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RE: Why Is A B777 Faster Than An A340

Fri Dec 22, 2006 12:45 am

One of the significant factor to note with aircraft speed and wing angles etc is the profile of the wing. Research in the 60's developed the suprcritical wing profile. See http://en.wikipedia.org/wiki/Supercritical_airfoil
The 747 was designed too late to incorporate the supercritical profile. Later civils use it extensively. Characteristics of supercritical wings relative to conventional designs include:
Less sweep needed > better low speed lift & structurally more efficient
Straighter trailing edge as a result of less sweep, therefore, in conjunction with above, lighter and less high lift devices
Deeper section, so structurally more efficient
Lower drag at design speed
Critical mach number - above which speed, drag picks up big time relative to the design speed.
I guess that the design speed for the 340 was picked to be lower than the 777 and the wing section designed accordingly. Fuel burn will be an issue.
 
beech19
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RE: Why Is A B777 Faster Than An A340

Fri Dec 22, 2006 12:48 am

Quoting Jogales (Reply 12):
You tell me

LOL Those monster GE-90's should be the 8th wonder of the world.  Smile

Quoting Antskip (Reply 15):
Aircraft fly within air, not on the ground. If +1000kmh was ground speed, it is just a record of speed relative to the ground - made up of the sum total of vehicular speed and local air movement. A plane flying at 100 kmh into a 100 kmh head wind would be not moving at all, relative to the ground. With a 100 kmh tail wind, it would be flying at 200 kmh relative to the ground, though the vehicle's air speed is unchanged.

I've done -mph in our Aeronca 7AC Champ. 27knot stall, 35knot headwind. LOL Look down and you are going backwards.
My father when he was flying KC-135's said they registered over 750mph ground speed going eastbound over northern USA heading back home. Gotta love the jetstream.  Smile

Quoting FlyDreamliner (Reply 18):
The 747 will still have a faster sprint speed than the A380, with 747-8 being able to do a max cruise of .89, and a max mach number of .92, as compared to a max mach on .89 on A380, but only by a shade, they'll cruise pretty close to each other.

 checkmark  FAST sprint speeds for the 747.
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keesje
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RE: Why Is A B777 Faster Than An A340

Fri Dec 22, 2006 12:48 am

Quoting Jogales (Reply 12):
What is there about the 777 that makes it that much faster than the A340?

You tell me

Which is faster, You tell me


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RE: Why Is A B777 Faster Than An A340

Fri Dec 22, 2006 12:58 am

Quoting Kiwiandrew (Reply 6):
but I have never heard of an A340-400

It is so fast, you can´t even see it Big grin

Quoting GRIVely (Thread starter):
Why Is A B777 Faster Than An A340

This topic made my day  Smile
 
beech19
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RE: Why Is A B777 Faster Than An A340

Fri Dec 22, 2006 1:15 am

Quoting Keesje (Reply 38):
Which is faster, You tell me

The 727 is... its got nothing to do with the motors... i think that point had already been made clear.
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LH648
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RE: Why Is A B777 Faster Than An A340

Fri Dec 22, 2006 1:48 am

Quoting Beech19 (Reply 2):
The crazy part is... the 747 will STILL be the fastest commercial aircraft in the world. And the 748 will be Mach .005 faster than the 744.

Tupolev 154 is faster.
 
beech19
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RE: Why Is A B777 Faster Than An A340

Fri Dec 22, 2006 2:20 am

Quoting LH648 (Reply 41):
Tupolev 154 is faster.

No its not. MAX Mach is .86. As we have already established previously the 747-400/ER/ERF MAX Mach is .92 and the 748i/F maybe more, but will be at least that.
http://en.wikipedia.org/wiki/Tupolev_Tu-154
http://en.wikipedia.org/wiki/Boeing_747
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LukasMako
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RE: Why Is A B777 Faster Than An A340

Fri Dec 22, 2006 2:23 am

Don't forget that ETOPS restrictions can make the 777 slower than the A340 on certain routes.
 
Lostmoon744
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RE: Why Is A B777 Faster Than An A340

Fri Dec 22, 2006 2:43 am

Re: TU-154: Curious to note the NATO reporting name as "Careless". My word!

What's the history behind the designation?
 
beech19
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RE: Why Is A B777 Faster Than An A340

Fri Dec 22, 2006 2:48 am

Quoting LukasMako (Reply 43):
Don't forget that ETOPS restrictions can make the 777 slower than the A340 on certain routes.

But that is more to do with the airline not getting a high enough ETOPS rating, not necessarily that the aircraft is actually "slower" it just has to travel farther to get there (and maybe STILL in less time if the detour was minimal).
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PhilSquares
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RE: Why Is A B777 Faster Than An A340

Fri Dec 22, 2006 3:01 am

Quoting Gigneil (Reply 9):
The A380 will cruise at M0.86, which is faster than the 744's standard cruise

The 380 will cruise at M.85

http://events.airbus.com/a380/seeing/learnandplay/figures3.asp

In reality, the 744 is closer to M.86. LRC is about .855-.856 if you're at your optimum altitude.
Fly fast, live slow
 
planemaker
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RE: Why Is A B777 Faster Than An A340

Fri Dec 22, 2006 3:11 am

Any Citation X pilots reading? Any validity to Cessna's claim that the Citation X is the fastest "civil" (which included commercial) aircraft flying? I remember that the Citation X received the Collier Trophy a few years back in part due to its speed (the engineering that went towards acheiving it).
Nationalism is an infantile disease. It is the measles of mankind. - A. Einstein
 
beech19
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RE: Why Is A B777 Faster Than An A340

Fri Dec 22, 2006 3:18 am

Quoting Planemaker (Reply 47):
Any Citation X pilots reading? Any validity to Cessna's claim that the Citation X is the fastest "civil" (which included commercial) aircraft flying?

It has a max cruise of .92 with sprints to like .94 at 51,000ft from what i hear. There is nothing like a Citation X, i love the GF's but Cessna did that one perfect. I'm not a pilot but have heard this echoed many times before (about the numbers).
http://citationx.cessna.com/specifications.chtml

[Edited 2006-12-21 19:19:54]
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Scooter01
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RE: Why Is A B777 Faster Than An A340

Fri Dec 22, 2006 3:43 am

Quoting Viscount724 (Reply 20):
The 707 is marginally faster than the DC-8,

This is why the Boeing people named it the DC-Late

Quoting Legoguy (Reply 13):
Since the a340 has wings with less sweep, does this give better low speed handling?

Is this why it looks so funny at final approach?
(I'm talking about the entertainment factor)

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