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The 777X is a program, covering two (or more) models: the 777-8 and 777-9. The one that flew yesterday was the first 777-9 -- a replacement for the 777-300ER, with significantly increased range, a stretched fuselage (it's slightly longer than the 747-8), and up to 426 seats. Increased use of lightweight materials and those whizzy folding winglets mean it's no heavier than its predecessor.
Maximum cargo capacity is roughly three-quarters that of a 747-8 by weight.
There's also a possible 777-10X model that will seat up to 450 passengers and is being pitched as a rival to the A-380 superjumbo.
The real miracle here is that the big four-engine jumbos are being replaced by a twin-jet. (This says something profound about advances in engine technology since 1970. Or even 1990.)
I always thought the real miracle was grandfathering that thing on the 777 type certificate.
Will pilots need new training if they are already 777-certified?
Complete noob here, so I am trying to improve my understanding.
Doesn't look too complicated (I mean, given what "complicated" means in aviation), the 777 is a relatively modern project.
Which tricks did they have to pull here?
Doesn't that make a plane less engine-fault tolerant? Completely noob here, but I would feel better if I flew in a 4-engine plane than 2-engine. In a 4-engine plane, even if 2 engines faults (like, bird strike), the other 2 will still make the plain airbone.
You don't necessarily lose engines instantly to bird strikes, they're most likely to happen at takeoff and landing, and it hasn't been an issue for the massive fleet of twin-engine short-haul jets.
The real concern is trans-oceanic long-haul. Supposedly modern engine failure rates have improved to the point that you're less likely to have problematic engine failures than a four-engine 70s-era 747.
Robust testing should make the dual engine failure scenario quite unlikely. That’s why the miracle on the Hudson was so remarkable.
ETOPS is the general set of rules for how far a plane with two engines can be from an airport. https://en.m.wikipedia.org/wiki/ETOPS
A bird strike (keep in mind birds fly in flocks) I'm guessing would either take out 1 engine (which is fine on a new 2 engine plane even during takeoff) so no benefit or take out all engines (or all engines on one side which again means just 1 engine on a 2 engine plane). A flock big enough to take out both engines on a 2 engine would be big enough I presume to take out all 4 on a 4 engine.
Four engines just means there's 4 things that can catastrophically fail and potentially damage the plane rather than 2.
A very good video on this subject matter of 4 Engines vs 2 Engines
Statistically, 2 engines are safer than 4. 4 engines will have twice the failure rate, and when engines fail the risk is collateral damage.
The associated concept in regulation is a certification (by plane model, e.g. for all Airbus A321) called ETOPS¹ (Extended Operations). The cert applies to twin engines and basically tells you that a plane can fly up to XXX minutes on 1 functional engine only (e.g. ETOPS = 60, then you have ETOPS 120, ETOPS 180 and currently ETOPS 240 is permitted on a case-by-base basis). Note that "ETOPS-180 and ETOPS-207 cover about 95% of the Earth" (how much you can reach while staying 180-207 minutes from an airport at normal altitude/speed).
The rational justification is not merely technical but rather empirical, proven by real-world data. Certifications usually because companies can demonstrate e.g. "N years of trouble-free XXX-minutes ETOPS experience". In other words, we've been doing it for this long and it works so there's statistically ever-less reasons to believe the certification is flawed.
So, despite all the stats you may collect about birds, and physical + ethological models to estimate how much chance there is it will happen twice to a twin engine plane on both reactors before it can land, it would only prove reality: it just doesn't happen. Or not in ways that more engines would solve. (Birds are a bigger problem for cockpit windows, though.)
Now, another additional bit of safety: all jetliner planes have a "fixed-wing" design, allowing "deadstick landing"². From wiki:
> All fixed-wing aircraft have some capability to glide with no engine power; that is, they do not sink straight down like a stone, but rather continue to glide moving horizontally while descending. For example, with a glide ratio of 15:1, a Boeing 747-200 can glide for 150 kilometres (93 mi) from a cruising altitude of 10,000 metres (33,000 ft).
More recent planes are usually ever better (the OG 747 is from 1969!) At the very least it allows the pilot to 'land' on sea and wait for evacuation in zodiacs. So even in the extremely unprobable event that ETOPS failed (the statistical outlier where a plane loses both engines), you'd probably just glide to the ground 100-200km away at most to reach some landing spot.
There are reasons why air travel is so safe, the safest of all, and most of those are empirical, real, tested then validated. That's why it was such a shame what Boeing did to the 737 MAX; and I hope the 777X program yields the safest planes we've ever seen from them, that they actually innovate in that respect.
Safe travels!
I am fascinated by the wings, you can see that they have been heavily optimised and wonder how much compute time went into perfecting them. I'd love to see a documentary on the design & construction. I have a carbon-fibre road bike and it is incredible how much they can tune the materal. Where it is rigid and where/ even how it flexes to dampen vibrations.
Interestingly, most of that article is about the 737 Max issues (the MCAS software is a disaster, it's a push to even call it engineering).
Recently I've been doing a teeny tiny bit of CFD again. You might be amazed at how little CFD goes in to wings. It's still a huge amount, but tunnel testing still wins. I was kind of surprised.
As best I can tell, CFD is still kind of like impedance-based home body fat scales. They're kind of directionally accurate but have a pretty high error.
I thought CFD would be a solved thing by now, but then I remembered how good (e.g. bad) weather prediction still is.
You might be interested in this bet on the LongNow site:
Some people think that wind tunnels will be obsoleted by computational fluid dynamics within the decade. Others think that the problems with CFD are not a lack of compute power but a lack of comprehensive understanding and modeling of the physics at play, and expect that wind tunnels will be with us for quite a while. (Personally, I believe in the progress of technology and expect an eventual if not near-term breakthrough in CFD software will eventually obsolete the wind tunnel, but I also think that institutional inertia will keep a lot of wind tunnels and businesses that purchase time in them in operation for a decade or more after CFD's big breakthrough...)
For those who don’t know (like me), CFD stands for “computational fluid dynamics”.
https://en.m.wikipedia.org/wiki/Computational_fluid_dynamics
F1 teams spend a lot of time in wind tunnels looking for correlation between CFD and Reality. If there isn't any then the year is almost lost, usually.
Construction is highly automated. Wing skins are created with automated fiber placement (AFP)
https://www.seattletimes.com/business/boeing-aerospace/massi...
The wings are assembled horizontally similar to the to A350.
> I'd love to see a documentary on the design & construction
“21st Century Jet” is a documentary about the building of the 777. Looks like it’s available on YouTube.
> The 252-foot-long passenger plane had been due to launch this year but has been delayed by some technical difficulties.
Is that related to the recent MAX issues, or to the fact shipping such a large aircraft on two engines only was much harder than expected?
Neither. The main delay is due to a problem with the GE9X engines. Some of the internal components were wearing out faster than expected so they had to redesign them.
Does this plan have a market? I thought the airbus A380 was having a very bad time and airlines don't want it anymore because it's too big.
A crucial difference is that, ultimately, 777X is a much smaller plane with easier operations compared to huge A380.
It needs no new special handling compared to the existing 777, which already had a higher amount of airports available as destinations, if only because it didn't need two-level tunnels for speedy embarkation/disembarkation.
Also, 777 has always served the long distance market, and this plane is essentially an extension for it without many of the downsides of both A380 and 747
It's not the capacity of the A380 that airlines dislike; it's that operating a heavy, double-decker quad-jet is expensive. It's estimated that A380s have an hourly operating cost that is double (or more) that of a 777. Which isn't surprising, considering an empty A380 weighs in at about 280 tons. An empty 777-300 weighs in somewhere around 180 tons.
Presumably the fuel efficiency (and emissions) are improved by a good chunk? 40 percent?
That would be amazing, given that current jets are already pretty efficient. Looks like its a little over 10% more efficient compared to older 777's: https://en.wikipedia.org/wiki/Boeing_777X#Efficiency
You’re right. I didn’t realize how much larger the new engines were.
Apparently they’ve only sold 300 of them. Same thing with the new updated 747.
Only 300? That’s like $150 billion of orders.
I was told they need like 1500 sold to turn a profit.
how many airlines are going to be thinking, hmmm lets let someone else fly them and see what happens.
This site has some more info about the 777 etc. Some articles may be paywalled though.
https://leehamnews.com/2020/01/25/third-time-is-the-charm-77...
Who wrote the software?
It wasn't a software problem.
It? I just mean in general, have their paid enough attention and money to the software as to the hardware?
If something comes out on the 777X that is similar to the 737MAX, it will break Boeing irreparably.
They can ride quite a while due to the fact that there is only one alternative in commercial flight (Airbus). I hope there is not a time when both companies have such an issue at the same time. That would disrupt travel.
So this plane has : a different fuselage, different wings, and different engines than the "regular" 777 but somehow is still called a 777.
Has Boeing learned anything from the past 12 month ?
The issue is not the name, it is the comprehensiveness of the training required. The MAX had iPad training only, and MCAS wasnt even in the manual, let alone the differences course.
Besides, the 777 wasn't designed for low loading at small airports.
It’s their risk minimisation strategy. If they call it something new, it would be perceived as a higher risk development. If they keep the existing name, it’s viewed as a mere improvement on the existing model.
To be fair, one of the primary reasons to use the same name is to minimize the training, among other things.
It just needs to behave like a regular 777 and you can partly do that using software emulation.
In reality, the only parts that are different are the wings and the engines. The rest of the systems are essentially the same.
The fuselage has the same diameter and design (just slightly longer).
Most people would not be able to tell the difference between a 777-9 and a 777-300ER.
Considering recent events I'm wouldn't be to interested in flying in it
No thanks. I don't mind beta testing software but I draw the line at beta testing the next Boeing aircraft.
Did the military division of Boeing have a hand in engineering the folding wingtips? It would make sense since McDonnell Douglas/Boeing have decades of experience doing this with the F-18. Then again it wouldn’t surprise me if the 777X team reinvented the wheel on this point.