Sponsor Message:
Civil Aviation Forum
My Starred Topics | Profile | New Topic | Forum Index | Help | Search 
A380 And Turbulence  
User currently offlineNeverest From France, joined Dec 2004, 51 posts, RR: 0
Posted (6 years 9 months 2 weeks 3 days 11 hours ago) and read 15118 times:

A topic that I have not seen discussed on this forum is how the A380 reacts to turbulence. I think as a general rule, the bigger an aircraft the less susceptible it is to turbulence. Therefore on this score the A380 should be quite stable and comfortable, encouraging many people to fly who otherwise put off flying. Do people who traveled on the plane have any observations?

40 replies: All unread, showing first 25:
 
User currently offlineOA260 From Ireland, joined Nov 2006, 26956 posts, RR: 58
Reply 1, posted (6 years 9 months 2 weeks 3 days 11 hours ago) and read 15045 times:

Yes I was wondering the same. I presume its similar to a 747 but maybe Im wrong??? Has anyone experienced turbulence yet on a A380 flight???

User currently offlinePrebennorholm From Denmark, joined Mar 2000, 6434 posts, RR: 54
Reply 2, posted (6 years 9 months 2 weeks 3 days 10 hours ago) and read 14944 times:

All Airbus FBW planes have the active turbulence compensation system, from the 318 and up.

Vertical acceleration sensors give input to the flight control software which calculates small, but very fast movements of ailerons and spoilers smoothen the ride in turbulence.

Lockheed pioneered something similar on the Tristar not too long before they discontinued airliner production. I don't know how far Boeing has come along this line, but I would be surprised if at least the 777 doesn't have a similar system.



Always keep your number of landings equal to your number of take-offs, Preben Norholm
User currently offlineTdscanuck From Canada, joined Jan 2006, 12709 posts, RR: 80
Reply 3, posted (6 years 9 months 2 weeks 3 days 9 hours ago) and read 14744 times:



Quoting Neverest (Thread starter):
I think as a general rule, the bigger an aircraft the less susceptible it is to turbulence.

Although that's generally true, it's not strictly because the airplane is bigger, it's because the wing loading is higher. Higher wing loading leads to less turbulence response.

Quoting Prebennorholm (Reply 2):
I don't know how far Boeing has come along this line, but I would be surprised if at least the 777 doesn't have a similar system.

I think the 777 has some kind of active load alleviation, but I'm not sure that it's designed to damp turbulence, just to protect the wing. The 787 definitely has it.

Tom.


User currently offlineLTU932 From Germany, joined Jan 2006, 13864 posts, RR: 50
Reply 4, posted (6 years 9 months 2 weeks 3 days 9 hours ago) and read 14684 times:



Quoting Prebennorholm (Reply 2):
Lockheed pioneered something similar on the Tristar not too long before they discontinued airliner production.

Are you talking about the Extended Wing/Active Controls feature on the TriStar 500?

http://www.tristar500.net/features/Technical_Profile.pdf (See page 13 of the PDF)


User currently offlineKhobar From United States of America, joined Mar 2006, 2379 posts, RR: 4
Reply 5, posted (6 years 9 months 2 weeks 3 days 8 hours ago) and read 14557 times:



Quoting Neverest (Thread starter):
A topic that I have not seen discussed on this forum is how the A380 reacts to turbulence. I think as a general rule, the bigger an aircraft the less susceptible it is to turbulence. Therefore on this score the A380 should be quite stable and comfortable, encouraging many people to fly who otherwise put off flying. Do people who traveled on the plane have any observations?

I highly, highly doubt any commercial airliner system can react fast enough nor compensate for severe turbulence conditions. And size doesn't seem to matter either considering the number of injuries that have happened on 747's. Most modern aircraft have active compensation for mild situations, but when it comes to turbulence it isn't going to make that much difference.

As for FBW, that is only an interface that translates flight control inputs to the flight control surfaces. Old fashioned cables and pulleys do exactly the same thing, and accelerometers can feed either system. FBW has the advantage of being lighter and more easily maintained - that is its real advantage in large, lumbering commercial airplanes as it can save money.

Bottom line - listen to the FA at the beginning of the flight - keep your seatbelt fastened at all times unless you really need to unfasten it for some reason. You really won't like the view from the ceiling.


User currently offlineIkramerica From United States of America, joined May 2005, 21516 posts, RR: 60
Reply 6, posted (6 years 9 months 2 weeks 3 days 7 hours ago) and read 14541 times:

It also has to do with wing flexibility and the length of the aircraft. It's not as simple as "FBW cures all" or "bigger is better" or any such statement.


Of all the things to worry about... the Wookie has no pants.
User currently offlineHodja From Singapore, joined Apr 2004, 91 posts, RR: 0
Reply 7, posted (6 years 9 months 2 weeks 2 days 20 hours ago) and read 13995 times:
Support Airliners.net - become a First Class Member!

Fwiw, I was on A380 SYD-SIN a week ago and we encountered a bit of turbulence an hour after takeoff. (enough to stop the food service for an hour or so)

The turbulence felt pretty much the same as on any major airplane. I couldn't discern any difference in either severity or manifestation.

Bottom line: Airplanes can't dodge turbulence. The sky controls the sky.


User currently offlineGeo772 From United Kingdom, joined Jul 2004, 519 posts, RR: 0
Reply 8, posted (6 years 9 months 2 weeks 2 days 20 hours ago) and read 13498 times:

IIRC the DC10 had a turbulence mode on the autopilot which reduced the responsiveness of its application of the control surfaces. This had the effect that the autopilot would not try so hard to fight the turbumence and so would put less load on the wings. I am not sure how effective it was at improving passenger comfort as I have only ever been on a DC10 once and thhe flight was as smooth as silk.


Flown on A300B4/600,A319/20/21,A332/3,A343,B727,B732/3/4/5/6/7/8,B741/2/4,B752/3,B762/3,B772/3,DC10,L1011-200,VC10,MD80,
User currently offlineCoal From United States of America, joined Aug 2006, 2030 posts, RR: 9
Reply 9, posted (6 years 9 months 2 weeks 2 days 20 hours ago) and read 13141 times:

I mentioned this on the trip report I wrote up on flying the A380 which can be found here

SQ 220: SYD-SIN On A380 Business Class (Pics) (by Coal Nov 11 2007 in Trip Reports)

After takeoff from Sydney, there was a significant amount of wind and, to my surprise, we were rattled about as though we were in much, much smaller plane, like a turboprop.

Cheers
Coal



Nxt Flts: VA SYD-CBR-SYD | CX SYD-HKG-SYD | QF SYD-DFW | AA DFW-MIA-DFW | QF DFW-SYD
User currently offlineIkramerica From United States of America, joined May 2005, 21516 posts, RR: 60
Reply 10, posted (6 years 9 months 2 weeks 2 days 18 hours ago) and read 12063 times:



Quoting Coal (Reply 9):
After takeoff from Sydney, there was a significant amount of wind and, to my surprise, we were rattled about as though we were in much, much smaller plane, like a turboprop.

Well my understanding is Airbus wings are stiffer and the surface area is incredible, and that can lead to more turbulence than say a 777 which has very flexible wings. But I've also been in a 777 that was tossed about for 3 hours near the Berring Strait.

Another thing that may work against the A380 is that it is shorter than it is wide. I remember as a kid the 747SP flights and how there was a lot of yaw in turbulence due to this. The massive vertical stabs of the A380 and 747SP are there for a reason, to try to prevent that, but even they can only do so much.

I'd still imagine the A380 will roll through smaller bumps more smoothly because of it's mass/inertia.



Of all the things to worry about... the Wookie has no pants.
User currently offline7cubed From United States of America, joined Jul 2006, 161 posts, RR: 1
Reply 11, posted (6 years 9 months 2 weeks 2 days 18 hours ago) and read 11986 times:

I flew a a320 last month and if it did have a "active turbulence compensation system" it wasn't working.  Smile


joe
User currently offlineBells From Singapore, joined Nov 2001, 159 posts, RR: 0
Reply 12, posted (6 years 9 months 2 weeks 2 days 18 hours ago) and read 11916 times:

Basically it's not the size of the aircraft, it's the wing loading that matters. The higher the wing-loading (ie the amount of lift required per square foot) the more stable the aircraft is in turbulence. The A380 actually has a relatively low wing-loading vs something like a 777-300ER, because the A380's wing is huge and has been designed to cope with very much higher gross-weight, stretched versions (ie A380-900, -1000 etc). So I wouldn't necessarily expect the A380 to fare better in turbulence than existing aircraft.

User currently offlineB747forever From Sweden, joined May 2007, 17066 posts, RR: 10
Reply 13, posted (6 years 9 months 2 weeks 2 days 18 hours ago) and read 11888 times:



Quoting 7cubed (Reply 11):
flew a a320 last month and if it did have a "active turbulence compensation system" it wasn't working.

That system works great for little turbulence, not for heavy turbulence.



Work Hard, Fly Right
User currently offlineScbriml From United Kingdom, joined Jul 2003, 12509 posts, RR: 46
Reply 14, posted (6 years 9 months 2 weeks 2 days 18 hours ago) and read 11484 times:
Support Airliners.net - become a First Class Member!

The A380 is so mighty that turbulence runs away when it sees it coming.

Signed,
Chuck Norris.



Time flies like an arrow, but fruit flies like a banana!
User currently offlineFaro From Egypt, joined Aug 2007, 1543 posts, RR: 0
Reply 15, posted (6 years 9 months 2 weeks 2 days 16 hours ago) and read 10018 times:

The A380 also has more broadside fuselage and empennage area making it more sensitive to lateral perturbations than say, the 777 or 747. And the wing is huge, basically designed to carry the stretched version of the plane as well as the present offering. I believe these factors would probably negate the added inertia it opposes to turbulence.

Faro



The chalice not my son
User currently offlineKeta From Germany, joined Mar 2005, 448 posts, RR: 0
Reply 16, posted (6 years 9 months 2 weeks 2 days 15 hours ago) and read 8961 times:



Quoting Khobar (Reply 5):
As for FBW, that is only an interface that translates flight control inputs to the flight control surfaces. Old fashioned cables and pulleys do exactly the same thing, and accelerometers can feed either system. FBW has the advantage of being lighter and more easily maintained - that is its real advantage in large, lumbering commercial airplanes as it can save money.

FBW does not work just replacing cables. In analog, a move on the yoke means a proportional movement on the aerodynamic surfaces. With FBW, computers read the input of the pilots, and based on the flight conditions, choose the best position of the actuators. Even if you introduce other measuring systems to the analog control system, you won't get the complexity you can get with FBW. So they don't do exactly the same. FBW has many advantages which cables and pulleys obviously lack.



Where there's a will, there's a way
User currently offlineGraphic From , joined Dec 1969, posts, RR:
Reply 17, posted (6 years 9 months 2 weeks 2 days 15 hours ago) and read 8699 times:



Quoting Khobar (Reply 5):
And size doesn't seem to matter either considering the number of injuries that have happened on 747's.

Size actually does matter, and in this case, bigger is better. It really all comes down to Newtons laws here, where Force equals Mass times Acceleration, if turbulent air applies an equal force on two aircraft, one a cessna and one an A380, the object with the smaller mass will have a greater acceleration component, where the object with the larger mass will see a greatly reduced comparative acceleration. Also, bigger aircraft that are relatively stable in turbulence do experience more wing loading than lighter aircraft that get tossed around.


User currently offlineMPDPilot From United States of America, joined Jul 2006, 991 posts, RR: 0
Reply 18, posted (6 years 9 months 2 weeks 2 days 14 hours ago) and read 8057 times:



Quoting Graphic (Reply 17):
Force equals Mass times Acceleration, if turbulent air applies an equal force on two aircraft, one a cessna and one an A380, the object with the smaller mass will have a greater acceleration component,

That is very true but you also have to look at that given a certain amount of wind the wind can apply more force to an A380 because the A380 is bigger. Size does matter to an extent but not just size, but also aerodynamics. It isn't as simple as a force being applied is equal, because it very rarely if ever is. The larger airplane has more force applied for a given wind and it is going faster and it is generally aerodynamically less stable than say a cessna.



One mile of highway gets you one mile, one mile of runway gets you anywhere.
User currently offlineMop357 From United States of America, joined Mar 2007, 85 posts, RR: 0
Reply 19, posted (6 years 9 months 2 weeks 2 days 13 hours ago) and read 7319 times:



Quoting Neverest (Thread starter):
A topic that I have not seen discussed on this forum is how the A380 reacts to turbulence. I think as a general rule, the bigger an aircraft the less susceptible it is to turbulence. Therefore on this score the A380 should be quite stable and comfortable, encouraging many people to fly who otherwise put off flying. Do people who traveled on the plane have any observations?

I think the bigger the airplane is the less the turbulence but to an extent. Bigger airplanes have big wings and big wings give more oppertunity to be tossed around by bad air. The 747 is a huge plane but it can also get rocked by turbulence just as any other airplane can.

Quoting Prebennorholm (Reply 2):
All Airbus FBW planes have the active turbulence compensation system, from the 318 and up.

Vertical acceleration sensors give input to the flight control software which calculates small, but very fast movements of ailerons and spoilers smoothen the ride in turbulence.

That probably helps but I don't think that would do anything against dips.


User currently offlineKhobar From United States of America, joined Mar 2006, 2379 posts, RR: 4
Reply 20, posted (6 years 9 months 2 weeks 2 days 11 hours ago) and read 6138 times:



Quoting Keta (Reply 16):
FBW does not work just replacing cables. In analog, a move on the yoke means a proportional movement on the aerodynamic surfaces. With FBW, computers read the input of the pilots, and based on the flight conditions, choose the best position of the actuators. Even if you introduce other measuring systems to the analog control system, you won't get the complexity you can get with FBW. So they don't do exactly the same. FBW has many advantages which cables and pulleys obviously lack.

I said FBW "is only an interface that translates flight control inputs to the flight control surfaces. Old fashioned cables and pulleys do exactly the same thing." I stand by that statement.

You are confusing FBW and EFCS. It is the EFCS which provides the additional capability you refer to. To make the point, Airbus have what's called "Direct Law" which bypasses the EFCS (e.g. in the event of a royal screwup) and transmits the pilot control inputs unmodified to the control surface actuators.


User currently offlineRemcor From United States of America, joined Feb 2006, 358 posts, RR: 0
Reply 21, posted (6 years 9 months 2 weeks 2 days 10 hours ago) and read 5842 times:

I hope they can't totally eliminate it in the future. I actually like turbulence, makes the flight more interesting; like it's a long roller coaster ride that most people don't want to be on.

User currently offlinePihero From France, joined Jan 2005, 4411 posts, RR: 76
Reply 22, posted (6 years 9 months 2 weeks 2 days 8 hours ago) and read 5637 times:
Support Airliners.net - become a First Class Member!

Before you go any further, you have to define turbulence.
It happens when one flies into an area of unstable air...it happens in gusty conditions...and basically it is caused by vertical and/or horizontal shifts in the ambient air.
Now consider :
1/- horizontal gusts. The effect on an airplane is dependant on the ratio of the gust speed to the aircraft TAS. So the faster the airplane, the less perceived the movement (associated with the *load factor* ). Therefore, an airliner is less susceptible than a light plane travelling slower.
2/- vertical gusts. here the effect depends -as been said in an earlier post- on the wing loading (the higher the W/S, the less the effect of the gust), AND the TAS (the higher the speed, the higher the load factor).
That said, the above applies to rather high g loads.
For just a *bumpy* ride, you'd have to consider
a/- the aircraft inertia
b/-the elasticity of the whole airplane, particularly the wings.On this aspect, ikramerica doesn't seem to have ever seen the wing flex of an A330 or 340 during takeoff.
c/-the damping systems of the airplane, beginning with the yaw damper which takes good care of transient lateral gusts and the *active control*, *gust alleviation systems* pioneered by Dassault on the Mercure and Lockheed on the Tristar 500 and present on Airbus products.



Contrail designer
User currently offlineWarren747sp From United States of America, joined Feb 2004, 1160 posts, RR: 0
Reply 23, posted (6 years 9 months 2 weeks 2 days 6 hours ago) and read 5557 times:

I will still take the 744 any day in heavy turbulence. I have seen a video once on Discovery Channel which shows the wings of the 747 flapping around like butterflies and it claims that they are designed to take the stress.


747SP
User currently offlineKeta From Germany, joined Mar 2005, 448 posts, RR: 0
Reply 24, posted (6 years 9 months 2 weeks 2 days ago) and read 5338 times:



Quoting Khobar (Reply 20):
You are confusing FBW and EFCS. It is the EFCS which provides the additional capability you refer to. To make the point, Airbus have what's called "Direct Law" which bypasses the EFCS (e.g. in the event of a royal screwup) and transmits the pilot control inputs unmodified to the control surface actuators.

I see what you mean. I was not confusing them, I just can't think of FBW without EFCS, because I call FBW the whole system, not just the replaced cables. I think you should have referred to this whole system on your original post, because that's how FBW airplanes work.



Where there's a will, there's a way
25 Baroque : The view itself from the ceiling is probably OK, Khobar, just it tends to be rather transient and immediately followed by the much inferior view from
26 Post contains images Dazeflight : LOL. One or two years ago, the discussion board was full with literally hundreds of threads regarding the A380 wake turbulence. Just do a search and
27 Ovlov : I flew from Sydney to Singapore on the SIA 380 on the 8th November. There was some very light turbulence during the flight and the Airbus handled it m
28 Pihero : Not entirely correct, Keta. You are thinking of the Airbus architecture in which the airplane systems tend to maintain the demanded g-load factor aga
29 Post contains images Khobar : Clearly FBW can exist without EFCS so, no, it is not "how FBW airplanes work". You might as well argue the autopilot is "how airplanes work".
30 Finkenwerder : It's called gust alleviation and all Airbus's....(Airbi ?) have it.
31 UAL747 : There are people on here that will say it doesn't matter what size of plane your in, it's up to the strength of the turbulence as it puts force on the
32 Jimbobjoe : At least not with compensation technology. Indications are that more sophisticated radar systems (I think based on doppler) will map the sky and the
33 474218 : Unlike the other aircraft you listed the L-1011 inboard and outboard ailerons are active in all flight conditions (flaps up/flaps down, takeoff/cruis
34 UAL747 : Actually, most modern aircraft have "drooping flaperons" if you want a term for it. Didn't know the L1011's worked during all phases of flight. What
35 UAL747 : The last flight I had over the Pacific going westward was complete hell in terms of turbulence. It was DFW-NRT on a 777. When it gets bumpy, I always
36 Post contains images Speedbird2263 : Ahh yes..The Famous Chuck Norris Factoids
37 UAL747 : Here's a great video of the 3 slotted aileron action on the A380. Watch the ailerons, especially close to touchdown. UAL
38 BillReid : Agree totally. Why not get the monies worth? We pay to take a roller coaster, why not enjoy the thrills on board.
39 OldAeroGuy : But they were about the wake turbulence created by the A380 and its impact on other airplanes. This thread is about the atmospheric turbulence create
40 Post contains images BR715-A1-30 : I must be a total Debbie Downer... I can't seem to get what all the excitement on the A380 is about? This totally SUCKS!! I mean, I am an aviation ent
Top Of Page
Forum Index

This topic is archived and can not be replied to any more.

Printer friendly format

Similar topics:More similar topics...
Shopping On The A380 And Turbulence posted Tue Dec 14 2004 19:50:57 by AirWales
A380 And The Triple Jetways posted Sat Oct 27 2007 10:42:35 by Stealth777
Emirates Seeks A380 And 747-8 Weight Control posted Sat Oct 27 2007 07:24:40 by EI321
Aboulafia's Comments On A380 And 787 posted Mon Oct 15 2007 07:43:52 by NYC777
The A380 And San Francisco Bay posted Sun Oct 7 2007 19:02:37 by Petera380
BA A380 And JFK posted Fri Sep 28 2007 00:46:40 by B777ER
AI In Talks With A And B; Eyes A380 And 748 posted Fri Sep 21 2007 18:17:14 by LAXDESI
Pictures Of The A380 And The B747 Together? posted Tue Sep 11 2007 19:12:18 by Il75
John Travolta, A380 And A Cheeky Photo posted Thu Aug 30 2007 20:04:57 by BOACVC10
QF A380 And LAX posted Fri Jun 1 2007 07:03:55 by Qantasguy