Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

China Will Resurrect the World's Largest Plane

popsci.com

Post reply on HN
Print view View original

111–119 of 119 posts

Re: China Will Resurrect the World's Largest Plane

#111

Post by jfb »

kragen wrote: post #102
maxerickson wrote: post #101

Earlier quoted context omitted.

Oh, another WWII scale event meets my definition of world gone to hell. I suppose I could have more clearly stated that I was arguing that the US is already leaning on large aircraft strategically, it wouldn't be a shift.

Oh, I agree! But I think we've seen a trend away from things like the 747-400 and the Ан-225 already over the last decades, and not just in the military, and I wonder why that is. It seems likely that the current war, if it really takes off, is going to be more significant than WWII. In WWII, major parts of Earth were not battlefields: the Americas, Antarctica, Australia, most of Africa, India, Mongolia, Siberia, par…

"I know not with what weapons World War III will be fought, but World War IV will be fought with sticks and stones." -- Albert Einstein

Re: China Will Resurrect the World's Largest Plane

#112

Post by icegreentea »

flukus wrote: post #107
icegreentea wrote: post #33

Earlier quoted context omitted.

Should probably begin by saying that there's no fundemental reason why China could not eventually develop their own modern turbofans without outside assistance. But obviously now is better for China. Designing and building modern turbofan engines is incredibly dependent on your mastery of materials science and fabrication. These are areas of science and engineering that are notoriously "art like" or even "black magic…

How much of that trial and error can be skipped with modern computer simulations?

In the field of materials and fabrication? Not that much. Fundamentally, the problem is that for many of the problems that we consider interesting in materials or fabrication, meaningful analogs to say.. the Navier Stokes equations don't even exist.

In the field of fluid and thermodynamics? Probably quite a bit. This is why I tried to emphasize the materials and fabrication bit.

Re: China Will Resurrect the World's Largest Plane

#113

Post by h4nkoslo »

flukus wrote: post #107
icegreentea wrote: post #33

Earlier quoted context omitted.

Should probably begin by saying that there's no fundemental reason why China could not eventually develop their own modern turbofans without outside assistance. But obviously now is better for China. Designing and building modern turbofan engines is incredibly dependent on your mastery of materials science and fabrication. These are areas of science and engineering that are notoriously "art like" or even "black magic…

How much of that trial and error can be skipped with modern computer simulations?

Things like metallurgy & fluid dynamics are notoriously difficult to simulate; this combines them in exciting ways.

Re: China Will Resurrect the World's Largest Plane

#114

Post by Osmium »

semi-extrinsic wrote: post #71
rayiner wrote: post #66

Earlier quoted context omitted.

Modern turbofans only stand up to their extreme operating conditions because of the use of exotic alloys and elaborate cooling techniques. Just because you know what shape a turbine blade should be doesn't mean you can copy the exotic alloy and manufacture it in a way that results in the correct crystal structure.

Not only exotic alloys, but single crystal blades. That's right, the blade is machined out of a single atomistically perfect crystal with no defects what so ever. The main point is that this reduces thermal creep, meaning you can have tighter tolerances and more power/efficiency.

> single atomistically perfect crystal with no defects what so ever

Nit-pick, but single crystals can (and do) still have defects. Your point about single crystal turbine blades being awesome I agree with completely though :)

Re: China Will Resurrect the World's Largest Plane

#115

Post by dang »

ting_bu_dung wrote: post #72
ovi256 wrote: post #20

It's obvious to me that China doesn't care that much about the AN-225 design as for the design of the D-18 turbofan. They still can't design or manufacture a heavy turbofan domestically. This has seriously hampered their heavy airlift project (the Y-20, who first flew using Soviet-designed low-bypass 12-ton thrust D-30 fans, which killed its range). The domestic WS-20 turbofan design that was supposed to power the pr…

it seems China is starting to militarize under its one dictator Xi, what with the island building in south china sea, desire to build aircraft engines, voicing economic/military threats to other countries when it cannot buy critical infrastructures in those countries (UK, Australia) and continued trade support for north korea (with its bigger nuclear bomb capability). It must be preparing for some sort of external co…

You've been using HN exclusively for political controversy. That's not a legit use of this site, so please don't use it that way.

HN exists for the gratification of intellectual curiosity, not political battles, and the two are mostly incompatible.

Re: China Will Resurrect the World's Largest Plane

#116

Post by ihaveajob »

chatmasta wrote: post #91
Someone wrote: post #84

"it carries a world record payload of 250 tons (to put this into comparison, it can carry around 300,000 lbs more than the US military's Boeing made C-17" What was the writer thinking? My readers won't understand what 250 tons is, so I'll use imperial metrics, too? Net effect is that this only makes full sense to those who understand both metric and imperial units. (I think a pound is 454 grams ('easy' to remember be…

I think it's more like "my readers don't grasp just how heavy 250 tons is." It's equivalent to saying "Mt Everest is nearly 6 miles, or 29,000 feet, high."

Not really. It's more like saying "Mt Everest is 8,848 meters high, or 2,483.6 ft taller than Mt Annapurna".

Edit: Oops, I just saw the previous response. That's what happens when you open 8 tabs and read as you can.

Re: China Will Resurrect the World's Largest Plane

#117

Post by kragen »

jfb wrote: post #111
kragen wrote: post #102

Earlier quoted context omitted.

Oh, I agree! But I think we've seen a trend away from things like the 747-400 and the Ан-225 already over the last decades, and not just in the military, and I wonder why that is. It seems likely that the current war, if it really takes off, is going to be more significant than WWII. In WWII, major parts of Earth were not battlefields: the Americas, Antarctica, Australia, most of Africa, India, Mongolia, Siberia, par…

"I know not with what weapons World War III will be fought, but World War IV will be fought with sticks and stones." -- Albert Einstein

From Wikiquote:

Interview with Alfred Werner, Liberal Judaism 16 (April-May 1949), Einstein Archive 30-1104, as sourced in The New Quotable Einstein by Alice Calaprice (2005), p. 173

Differing versions of such a statement are attributed to conversations as early as 1948 (e.g. The Rotarian, 72 (6), June 1948, p. 9: "I don't know. But I can tell you what they'll use in the fourth. They'll use rocks!"). Another variant ("I do not know with what weapons World War III will be fought, but World War IV will be fought with sticks and stones") is attributed to an unidentified letter to Harry S. Truman in "The culture of Einstein" by Alex Johnson, MSNBC, (18 April 2005). However, prior to 1948 very similar quotes were attributed in various articles to an unnamed army lieutenant, as discussed at Quote Investigator : "The Futuristic Weapons of WW3 Are Unknown, But WW4 Will Be Fought With Stones and Spears". The earliest found was from “Quote and Unquote: Raising ‘Alarmist’ Cry Brings a Winchell Reply” by Walter Winchell, in the Wisconsin State Journal (23 September 1946), p. 6, Col. 3. In this article Winchell wrote:

Joe Laitin reports that reporters at Bikini were questioning an army lieutenant about what weapons would be used in the next war.

“I dunno,” he said, “but in the war after the next war, sure as Hell, they’ll be using spears!”

It seems plausible, therefore, that Einstein may have been quoting or paraphrasing an expression which he had heard or read elsewhere.

https://en.wikiquote.org/wiki/Albert_Einstein

See also http://quoteinvestigator.com/2010/06/16/future-weapons/

Re: China Will Resurrect the World's Largest Plane

#118

Post by chiph »

avmich wrote: post #77
chiph wrote: post #27

Earlier quoted context omitted.

I doubt there's enough heavy commercial cargo in the world that would support a fleet of these aircraft. While the current AN-225 is busy, it doesn't appear to be busy enough to financially justify restarting construction on the second airframe. I expect this is desired for a few reasons - heavy military airlift, to match what the US has had since Vietnam with the C-5 Galaxy. Access to licensed construction of the D-…

There is a known big problem of transporting big rocket stages from the place where they are manufactured to places where they are launched. Saturn-5, one of the biggest rockets so far in the world, was manufactured near a river and transported by a big ship. This sidestepped the problem of roads. Energiya, the Soviet heavy rocket which launched Buran, had its huge second stage flown by a plane to Baykonur. In 1960-s…

Blue Origin says their next body (New Glenn) will be 23' (7 meters) in diameter. They're building a new facility near Cape Canaveral Air Force Station for it.

Re: China Will Resurrect the World's Largest Plane

#119

Post by finid »

Symmetry wrote: post #75
finid wrote: post #45

Earlier quoted context omitted.

Practically every single paragraph in that article, including image captions, either infer or directly address the economic reasons for why China would want the An-225 and its technologies.

Yes, nobody's disputing the idea that there are times when you need a single large cargo hold. The question is whether the plane would be economically competitive in terms of regular cargo. In other words is China going to build 3 of these and have them spend most of their lives sitting in hangers or are we going to be seeing hundreds of these flying all over China? That's something the article doesn't try to address…

Imagine how much it's going to save the Chinese to fly in all those raw materials from Africa and South America on an An-225, instead of shipping them.
Post reply on HN