The Boeing 777X is so big that it requires folding wingtips...

"doodon2whls" (doodon2whls) 12/09/2013 at 12:05 • Filed to: Planelopnik, Boeing, 777X

7

100

The next generation 777, dubbed the 777X, is a big undertaking @ Boeing, and it just started scale model wind-tunnel testing this week in Farnborough, England in cooperation with Qinetiq.

The goals are lofty for the 777X. The 777-9X is projected to have the lowest per-seat cost of any commercial aircraft [400 seats, and range of 8200 Nautical miles (>9400 miles)]. The 777-8X is projected to have an operating range of over 9300 nautical miles (>10700 miles) ! They intend to accomplish these feats utilizing Composite wing construction techniques (lowering mass), two high efficiency GE9x Turbofans, among other aerospace engineering wizardry.

Part of the optimization of the wing design has resulted in a 71.1 meter (233 ft !) wingspan which would prove difficult to fit into congested airports around the world. The solution ? Folding wingtips. Yep... The old trick used to cram fighters on carrier decks has made it to the commercial air transport world... The improvement in efficiency had better be worth the added cost, complexity and reliability gremlins these folding wingtips are sure to introduce.

Check out more details of the 777X !!!error: Indecipherable SUB-paragraph formatting!!! .

[Image Source: ASDNews, Boeing]

Jayhawk Jake > doodon2whls 12/09/2013 at 12:30

7

They actually planned for this on the original 777, but no one bought it.

I'll be curious to see if it's actually necessary for this one though and if any airliner actually options it. That mechanism can't be light...

Bad Idea Hat > Jayhawk Jake 12/09/2013 at 12:34

0

Additionally, the mechanism is going to be one hell of a crapper to maintain. Ask anyone who worked on carrier-based aircraft in the navy.

f86sabre > doodon2whls 12/09/2013 at 12:34

1

From what I remember folding tips were discussed in the original 777 design and I believe the the current models are designed with provisions to accept them.

FJ80WaitinForaLSV8 > Jayhawk Jake 12/09/2013 at 12:36

1

How common is it for airplanes to have multiple wing options? Sounds like a big PITA for all involved.

Racescort666 > FJ80WaitinForaLSV8 12/09/2013 at 12:38

0

That's gotta make the Type Certificate complicated.

PilotMan > doodon2whls 12/09/2013 at 12:39

0

Seems like she could still fly with an in-flight malfunction as well.

abgwin > doodon2whls 12/09/2013 at 12:39

0

OK, but the A380's wingspan is already 260+, so...

Nibby > doodon2whls 12/09/2013 at 12:39

1

Mankind has had folding technology for large parts for thousands of years. It's about time we implement them in for civilian air travel!

doodon2whls > abgwin 12/09/2013 at 12:40

2

The A380 can only operate out of specific airports with special gate provisions.

abgwin > doodon2whls 12/09/2013 at 12:43

0

And the A380 is probably the target for this 777 variant, right?

GOAT__RODEO > doodon2whls 12/09/2013 at 12:44

1

I'm curious if this also allows for additional winglet tuning in flight vs. just a space savings deal.

shieldsdb > abgwin 12/09/2013 at 12:45

0

Have you ever seen how they make the wings? They take two huge blocks of aluminum, slide them together under a 20 ton (i think 20 ton) spinning vice. The pressure and rotation causes the aluminum to bond together, making one solid piece. Freaking amazing!

Turbineguy: Nom de Zoom > Jayhawk Jake 12/09/2013 at 12:46

1

From what I've read the folding wingtips will be standard.

cartapacio > doodon2whls 12/09/2013 at 12:46

1

More things that could go wrong.

HammerheadFistpunch > doodon2whls 12/09/2013 at 12:47

1

Those GE9x engines are so freaking amazing. 115,000+ lbs of thrust...each!

Dick Nickels > FJ80WaitinForaLSV8 12/09/2013 at 12:47

0

Variable sweep wings add a lot of weight, too. Several variable sweep designs were considered for the American supersonic transport, but the Concorde sort of made it a moot point.

Turbineguy: Nom de Zoom > Bad Idea Hat 12/09/2013 at 12:48

0

If you remove the corrosive environment of a carrier from the equation, I don't think the folding mechanism's maintenance should be too bad to deal with. I'd want to be damn sure the downlocks are in place before the takeoff roll starts though..

bobrayner > abgwin 12/09/2013 at 12:48

1

Not especially; they have a big difference in capacity. However, all airliners compete to some extent, considering how airlines can tweak prices, routes, and frequencies &c...

DarthDuster > doodon2whls 12/09/2013 at 12:49

11

No one finds it more intriguing that Boeing are doing initial wind tunnel testing at Farnborough?

Umm Great Britain Fuck Yeah?

*because you know being British, it's not terribly on to brag about such things ;)

Turbineguy: Nom de Zoom > PilotMan 12/09/2013 at 12:49

1

What type of malfunction? One wingtip folding up would create a pretty serious imbalance in lift I'd think, and the roll response might be too much for normal aileron authority to counteract.

Nitzer Ebblestone > doodon2whls 12/09/2013 at 12:50

0

Actually, it folds up so they can get it out of Washington State quicker so as to avoid paying the unionized shop workers here and go to a cheaper state that's more willing to underwrite everything Boeing wants. Boeing believes in Christmas, oh yeah.

BTW, is it just me or is Kinja hosed for everyone with IE10 on Windows 8? It seems to be less irksome on Chrome on the same platform and Safari on OS/X (Lion) but for about 2 weeks now it seems to be pretty comprehensively hosed on a Windows machine.

StevenG > Turbineguy: Nom de Zoom 12/09/2013 at 12:51

1

Not like it will fall out of the sky without them.

Even if they came off the plane would be fine. This is just to increase wingspan to reduce loading and thereby increase fuel economy.

HammerheadFistpunch > Bad Idea Hat 12/09/2013 at 12:53

0

On the plus side, these winglets probably are so light and carry so little load that the mechanism can be fairly light and simple, i.e. let the airfoil force keep them locked in the flight position and only use heavy lifting for the taxi position.

StevenG > DarthDuster 12/09/2013 at 12:53

2

It's a Boeing, 'MURICA !

HammerheadFistpunch > cartapacio 12/09/2013 at 12:54

0

of the hundreds systems and millions of parts, this adds a tiny TINY fraction of additional complexity.

Turbineguy: Nom de Zoom > StevenG 12/09/2013 at 12:54

0

"Even if they came off the plane would be fine"

Really? Losing a major structural part of the wing would not be a big deal? I wouldn't want to be the test pilot for THAT round of certification testing..

55_mercury > DarthDuster 12/09/2013 at 12:54

0

Not really. Commercial aircraft manufacturing is pretty similar to automotive manufacturing with engineering, testing, manufacturing, development, and sales located globally. A good example: When I was a kid in rural Tennessee, there was a smaller plant that produced fuel injectors for ( I can't recall) but it was either Jaguar or Rover group. So stranger things have occurred...

StevenG > Turbineguy: Nom de Zoom 12/09/2013 at 12:57

1

Major structure?
These are just winglets on steroids. Fuel economy would be the major impact and asymmetry would be what the pilots would have to fight. Not like it would suddenly spiral into the dirt.

6shelBfan6 > doodon2whls 12/09/2013 at 12:58

0

What a beautiful aircraft! Boeing knows how to make them pretty, well except for the '67.

kent-skinner > Turbineguy: Nom de Zoom 12/09/2013 at 12:58

2

I'm willing to bet that Boeing has considered this possibility, and the computerized flight controls can deal with it.

FlyingZona > PilotMan 12/09/2013 at 13:00

0

A pre-flight pilot malfunction might not do it any favors. Forgetting to put them down before taking off could be disastrous.

dal20402 > Jayhawk Jake 12/09/2013 at 13:02

1

The 777X folding wingtip is much simpler than the planned folding wingtip for the original 777-200. The 777X tip incorporates no control surfaces and is only intended to get the 777X into gates sized for the original 777. The 777-200 folding tip was much bigger, and included the outboard aileron and all of its associated plumbing and wiring. It was intended to fit the 777-200 into 767 gates.

The 777X tip should be very reliable, and if it does fail the consequences (a slight fuel burn penalty) will be minimal.

Turbineguy: Nom de Zoom > kent-skinner 12/09/2013 at 13:02

1

Computerized or not, if an asymmetric lift condition occurs and roll authority is exceeded it's gonna be a bad day for everybody onboard. I'd guess the Part 23 testing will include failure of one or both folding mechanisms to see what will happen. Wouldn't want to be on that test acft though...

Atomic Buffalo > doodon2whls 12/09/2013 at 13:02

2

The Airbus 380 has a 71.75m wingspan.

The Boeing 747-8 has a 68.4m wingspan.

The Boeing 747-400 has a 65m wingspan.

The Boeing 777X wings fold to 64.8m.

I can see why airlines might go for that. A lot of airports were built around the classic 747...

dal20402 > Turbineguy: Nom de Zoom 12/09/2013 at 13:04

0

These wingtips are a tiny part of the wing area. The imbalance if one failed, or even if one fell off, would be minimal. Their purpose is just to increase span, which decreases drag.

Stefan25 > DarthDuster 12/09/2013 at 13:04

0

I could drive there in about 30 minutes, most my mates went to sixth form there... i feel famous!

dal20402 > FlyingZona 12/09/2013 at 13:04

0

Failing to fold them before takeoff would have minimal effect. Again, they are a tiny part of the wing area — they are there just to increase span.

PilotMan > Turbineguy: Nom de Zoom 12/09/2013 at 13:06

0

There is a whole suite of control surfaces available to counter the loss of lift. I'm sure the computer could counter with slat deployment, spoilers, maybe not even requiring aileron. Essentially it's just the wing tip.

Turbineguy: Nom de Zoom > StevenG 12/09/2013 at 13:06

0

How do you know this? They're not winglets they're wing extensions, big difference. And by definition they are part of the wing structure so yeah it's rather important I'd think.

dal20402 > Turbineguy: Nom de Zoom 12/09/2013 at 13:06

2

The loss of one folding wingtip will have the same effect on roll authority as a tire 5 psi below proper pressure has on your ability to steer your car.

Turbineguy: Nom de Zoom > dal20402 12/09/2013 at 13:07

0

I understand their purpose, but nobody knows yet what their failure mode might be. Fold up or fall off, I'm thinking it's going to have an effect on roll control.

dal20402 > f86sabre 12/09/2013 at 13:08

0

The 777X wing is entirely new, and this folding mechanism is also a very different (and much simpler) concept than the one planned for the 777-200.

Turbineguy: Nom de Zoom > dal20402 12/09/2013 at 13:08

0

You seem pretty sure of this. Are you a Boeing engineer?

dal20402 > abgwin 12/09/2013 at 13:09

2

The idea is that the 777X can use any gate that existing 777s can use. That gives it much more flexibility than the bigger A380.

Bacon > doodon2whls 12/09/2013 at 13:09

3

Great, one more thing for me to watch out the window. You know, just to make sure the pilots complete their checklists...

Tj Wenger > DarthDuster 12/09/2013 at 13:09

2

Except is not "Great Britain, Fuck Yeah" That's uncouth. Its probably more "Great Britain, Cheerio!"

kent-skinner > Turbineguy: Nom de Zoom 12/09/2013 at 13:09

2

Thank dog you thought of this before anybody at Boeing. Think of all the lives you just saved.

Turbineguy: Nom de Zoom > PilotMan 12/09/2013 at 13:10

0

True, but IIRC slat deployment is speed-restricted. If a wingtip fails in cruise flight at .8X mach what then? That's way above flap and slat speed. Interesting thought exercise here.

Clutchman83 > PilotMan 12/09/2013 at 13:11

0

I would venture that folding the winglets down will be part of the pre-takeoff checklist and a failure would result in not taking off.

Turbineguy: Nom de Zoom > kent-skinner 12/09/2013 at 13:11

0

Consider this a thought exercise, my snarky chum. On an auto blog, no less.. :)

StevenG > Turbineguy: Nom de Zoom 12/09/2013 at 13:13

0

Wing extensions and winglets serve the same purpose. To try to get the wing loading down, thus fuel economy up. Sure they are important, but boeing is not some fly by night operator. They are only 11' long, each. We are not talking about a large structure here in comparison.

Hart88 > 6shelBfan6 12/09/2013 at 13:13

0

and the '57

johnny555 > doodon2whls 12/09/2013 at 13:13

0

sorry to be "that guy", but....

!!! UNKNOWN CONTENT TYPE !!!

Gizmodo: Folding Wings Will Let Boeing's New 777x Squeeze Into Small Airports

doodon2whls > johnny555 12/09/2013 at 13:14

0

Thanks, Johnny. Clearly, we hadn't seen that over on Gizmodo...

FlyingZona > dal20402 12/09/2013 at 13:15

0

You're probably right. They look quite large from the camera angle in the second rendering.

dal20402 > Turbineguy: Nom de Zoom 12/09/2013 at 13:15

3

It's math. The 777X wing area is going to be roughly 466 square meters (which is an increase of 30 compared with the 777-200LR/300ER wing with raked tips). Of those 466 square meters, the folding portion will be roughly 20 square meters. If both folding wingtips failed, you'd still have more wing area than the 777-300ER, lifting the same weight.

Hart88 > doodon2whls 12/09/2013 at 13:16

0

Rather than introducing a complex (and heavy) mechanism, why not just build the wing that way?

YesILoveCars > doodon2whls 12/09/2013 at 13:16

0

Air Forces have been using folding wings, and swing wings, for a long time. Seems like the gremlins should be largely worked out by now. Check the crazy folding wings on the E2C Hawkeye.

Turbineguy: Nom de Zoom > Clutchman83 12/09/2013 at 13:17

0

Checklists are nice but crews have missed items before that led to bad outcomes. Skipping something like this would probably trigger a master caution when the power is advanced on takeoff. (configuration alarm?) Kinda like an electronic bitch-slap for the crew.

aismo > doodon2whls 12/09/2013 at 13:17

0

The wing-length figures might be off since these wings are so backswept… you could technically have longer wings that protrude less from the plane.

johnny555 > doodon2whls 12/09/2013 at 13:18

1

I feel like a jerk.

More 777X never hurts.

dal20402 > FlyingZona 12/09/2013 at 13:18

0

That's a neat picture, but the numbers tell you more... the folding surface is less than 5% of total wing area and only a bit more than 5% of span.

twosixteen > Turbineguy: Nom de Zoom 12/09/2013 at 13:19

0

They only account for a fraction of the total lift generated by the aircraft. Losing one (or both) wouldn't exactly cause it to fall out of the sky. Asymmetrical lift would be the major problem (as StevenG mentioned), but pilots are trained to deal with much worse.

Clutchman83 > Turbineguy: Nom de Zoom 12/09/2013 at 13:22

1

As someone who worked as an aircraft crew member I can assure you that checklists are taken very seriously. If a master caution goes off for a checklist item you fucked up. Q3, have fun at the safety inquiry.

SgtHop > Hart88 12/09/2013 at 13:23

2

Because wings need to be horizontal to work.

LyleLanley > doodon2whls 12/09/2013 at 13:23

0

UKPDXWRX > Nitzer Ebblestone 12/09/2013 at 13:24

2

Boeing believes in staying competitive and if they don't Airbus will absolutely eat their lunch.

Turbineguy: Nom de Zoom > StevenG 12/09/2013 at 13:25

0

Not exactly. Winglets reduce drag, wing extensions add lift by increasing span. I'm sure Boeing is all over this - they have to get it part 23 certified. I'm just curious to know what failure modes will be tested for certification.

PilotMan > Turbineguy: Nom de Zoom 12/09/2013 at 13:25

1

The hinge joint looks to be engineered for strength and simplicity. If the lock fails, and wing tip goes vertical, at least there wouldn't be a drastic change in drag.

The F-15 missing-wing landing video along with the all the WWII flak-damaged bomber pics and films give me the impression that losing that wing tip would be survivable for the aircraft.

I don't know how many times I've flown simulators with wing damage for fun, seeing how much wing can be removed before the plane refuses to fly straight and level. Tearing a wing off a biplane when flying a flight simulator is a fun challenge.

Turbineguy: Nom de Zoom > Clutchman83 12/09/2013 at 13:27

0

Former charter pilot here (turboprops). Yes, following checklists was beaten into us by our CP too but my point was that there have been enough Part 121 accidents caused by cklist items being skipped/missed.

Turbineguy: Nom de Zoom > PilotMan 12/09/2013 at 13:30

0

"losing that wing tip would be survivable for the aircraft"

I'd guess Boeing's design wouldn't be certifiable if a failure weren't survivable.

formerlydickmove > doodon2whls 12/09/2013 at 13:30

14

Hard to fold:

anavi8or > dal20402 12/09/2013 at 13:33

0

I agree with dal20402.

Hart88 > SgtHop 12/09/2013 at 13:34

1

Not on the ends, obviously.

SgtHop > Hart88 12/09/2013 at 13:35

1

Yes, on the ends. They're not for winglets, it's for use on the ground so it can fit into airports.

Prophet of hoon > doodon2whls 12/09/2013 at 13:35

0

they had me at turbofan not jet motor.... that's pretty cool

Clutchman83 > Turbineguy: Nom de Zoom 12/09/2013 at 13:37

0

C -17 loadmaster here, maybe the civilian side is different but I'd get bitch smacked by an instructor if I skipped ANY checklist item. Folding wings seems to be a fairly big one that the entire crew would be paying attention to.

Jartosz > doodon2whls 12/09/2013 at 13:39

0

I appreciate the fact that you can only make a big airliner look slightly different from another, but other than the wing tips, I honestly wouldn't be able to tell which Boeing this is. Perhaps in person a little better because I know the relative size of the different planes, but still...style wise, its nothing to get too excited about.

Nitzer Ebblestone > UKPDXWRX 12/09/2013 at 13:47

0

That's the excuse corporations always give to avoid paying taxes and to get some poor 3rd world state or country to underwrite their production costs. States end up footing the bill. Washington has just given Boeing $9B in guarantees (IIRC) if it builds the 777X here but they are still shopping the plane around because they want to break the union. Basically unless they get everything they want they will take their ball and go home. They'd already have gone to China if it guaranteed their IP wouldn't be ripped off. You know that when they have moved to Alabama and employ non-unionized workers at half the rate they pay the Washington employees that the corporate execs are going to receive massive bonuses, pay rises and stock options. It's the workers' lunch that will be getting eaten, not Boeing's.

Mailbox Cancer > DarthDuster 12/09/2013 at 13:48

2

I want to see a "Great Britain Fuck Yeeeaaarrhhhh!" spoof.

Hart88 > SgtHop 12/09/2013 at 13:50

0

Ah, got it.

FlyingZona > Turbineguy: Nom de Zoom 12/09/2013 at 13:56

0

A great example being Northwest Flight 255. Missed putting down the flaps and slats then the warning didn't go off because the circuit breaker was tripped. Ended with the plane in the highway at the end of the runway. It seems so basic but it could be overlooked again.

Foo2rama > Atomic Buffalo 12/09/2013 at 13:59

0

The problem is alot of airports (read high volume regional) that the 777 is meant to service cannot take 747's let alone the big airbus. The Airbus can only operate out of less then 50 airports world wide. AFIAK that is due to size and not to infrastructure needed to plane and deplane that bird.

NO > PilotMan 12/09/2013 at 14:02

0

Two things: as stated, minimal overall effect relative to the mass of the aircraft and overall lift surfaces. Commercial aircraft can handle an engine falling off and taking a chunk of the wing with it and still fly and land safely; that little extra bit at the end won't crash it. It's mostly there for fuel efficiency.

Next, it's really not difficult to make the wing deploy at a certain speed, as a fail-safe to prevent forgetting it on takeoff. Or make the alarms and instruments really really obvious and annoying if you forget it.

Turbineguy: Nom de Zoom > FlyingZona 12/09/2013 at 14:06

0

I was thinking of Spanair flt 5022 from 2008; same issue. No alarm from TOWS resulting in attempted takeoff without flap or slats.

Turbineguy: Nom de Zoom > Clutchman83 12/09/2013 at 14:11

1

No different on the civil side. When I was a f/t CFI my students would get verbally bitch slapped if they skipped any CL items. I knew the FAA examiner would bust them on their checkride for doing the same, so they needed to train to that standard. I can just imagine the yelling from the paying customers in back if a 777X crew started the takeoff roll with the wingtips still up. You KNOW that would end up on YouTube within minutes..

BTW, thanks for your service. I'm a USAF vet.

Jagvar > formerlydickmove 12/09/2013 at 14:13

8

.

ME 4-12 > Turbineguy: Nom de Zoom 12/09/2013 at 14:14

0

I'd think that if one failed, they'd just lift the other one up so they would have the same area for lift.

Turbineguy: Nom de Zoom > dal20402 12/09/2013 at 14:14

0

This makes sense, even to my math-challenged brain. I guess an asymmetric deployment prob wouldn't be a huge issue then.

Turbineguy: Nom de Zoom > ME 4-12 12/09/2013 at 14:15

0

Maybe. From what one poster said the total area of the wingtips isn't huge, so my concern about asymmetric lift is probably unfounded.

davedave1111 > Turbineguy: Nom de Zoom 12/09/2013 at 14:18

0

Have a read up on what winglets/tip-extensions actually do, and how they work. They're more about reducing drag than generating lift. It's not just about the proportion of the surface area, which is already low, but that that part of the wing isn't really generating any lift.

Still, you'd think they'd make them fold down. Folding up appears to be the wingtip equivalent of the suicide door.

BionicPhil > Mailbox Cancer 12/09/2013 at 14:21

5

bmw325_num99 > Hart88 12/09/2013 at 14:22

1

I think these winglets fold up while taxiing and go horizontal for flight. they do look like winglets though

FlyingZona > Turbineguy: Nom de Zoom 12/09/2013 at 14:22

0

Same plane, same issue. It's very unfortunate.

Turbineguy: Nom de Zoom > davedave1111 12/09/2013 at 14:23

0

I'm aware of how they work, but didn't realize the total area was that small. Also hadn't considered that little lift comes from the tips like you said.

Mailbox Cancer > BionicPhil 12/09/2013 at 14:24

3

I have a feeling that all the call/response verses would just be:

The Queen! Fuck Yeah!

The Queen! Fuck Yeah!

The Queen! Fuck Yeah!

The Queen! Fuck Yeah!

The Queen! Fuck Yeah!

The Queen! Fuck Yeah!

The Queen! Fuck Yeah!

The Queen! Fuck Yeah!

The Queen! Fuck Yeah!

The Queen! Fuck Yeah!

The Queen! Fuck Yeah!

The Queen! Fuck Yeah!

Dr. Who! Fuck Yeah!

Fish & Chips! Fuck Yeah!

The Queen! Fuck Yeah!

The Queen! Fuck Yeah!

The Queen! Fuck Yeah!

The Queen! Fuck Yeah!

The Queen! Fuck Yeah!

The Queen! Fuck Yeah!

The Queen! Fuck Yeah!

The Queen! Fuck Yeah!

The Queen! Fuck Yeah!

The Queen! Fuck Yeah!

The Queen! Fuck Yeah!

The Queen! Fuck Yeah!

The Queen! Fuck Yeah!

You can tell a Finn but you can't tell him much > davedave1111 12/09/2013 at 14:29

0

Two words "ground strike". Better to have the tips fold up to minimize the risk of bashing them on a ground vehicle or other obstacle.

Atomic Buffalo > Foo2rama 12/09/2013 at 14:29

0

The current 777-200LR, Cargo, and -300ER variants have a 64.8m wingspan.

The Airbus A350 has a 64.8m wingspan.

Yes there are 777 variants with a smaller 60.9m wingspan, but can we agree it's too soon to call it a problem that the only announced 777X variants so far mimic the larger-winged 777s? They're no doubt addressing what they think are the higher priorities, i.e. with the most aggressive competition (A350).

Seraph99 > 6shelBfan6 12/09/2013 at 14:30

0

and the '87. Looks like a flying dildo to me. At least the '67 looks like a junior 777

You can tell a Finn but you can't tell him much > DarthDuster 12/09/2013 at 14:31

0

That actually did jump out at me. I would assume Boeing has in-house wind tunnels, why wouldn't they use them? Unless maybe they make all models to a certain scale, and with the big wingspan on this their tunnels won't fit it.