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China Will Resurrect the World's Largest Plane

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Re: China Will Resurrect the World's Largest Plane

#52

Earlier quoted context omitted.

Fluid dynamics and combustion chambers. It's rocket science, a long, expensive trial-and-error development process. And unlike other sciences, most of the results are never published so each entity has to recreate the foundations themselves. It takes money, time, and dedicated careers.

Why not to just buy one aircraft and reverse engineer its engines? What is the problem with just copying exact copy of existing engine?

Because a lot of the "knowledge" comes from the engineering process much of it is trial and error and often it's not documented in the theoretical books ;)

This is why it's easy to lose the ability to produce something e.g. the big rockets that NASA used to make.

China can make a copy of the engine but it would not gain sufficient insight into why they chosen to design it exactly as it did so making adjustments would not be very easy or possible at all without putting almost as much R&D effort into it as making a whole new engine from scratch and debugging things would also be near impossible.

There is a reason why there are only a few engine manufacturers in the world, it's very hard work, and as far as big engines go then only RR and GE are really in the game.

Re: China Will Resurrect the World's Largest Plane

#54

Earlier quoted context omitted.

Why not to just buy one aircraft and reverse engineer its engines? What is the problem with just copying exact copy of existing engine?

In this case U.S. government restrictions probably restrict China from buying U.S.-manufactured planes. I doubt Antonov wants to sell its only An-225.

Antonov is selling the unfinished frame of second AN-225 and rights and documentation as far as I remember.

Re: China Will Resurrect the World's Largest Plane

#55
post #7

To make it possible Ukraine and Chine will need to redevelop many technologies that were used to build Mriya. The technologies were gone when USSR collapsed.

Not that many the bulk of manufacturing was done in Ukraine what was sourced externally can be sourced from subcontractors. For example engines are manufactured by Motor Sich (Ukraine based) which is still a fairly large engine manufacturer etc.

Re: China Will Resurrect the World's Largest Plane

#56
post #41
post #16

So this was originally made to carry the USSR's Buran space-shuttle-like project. I'd never heard of Buran before, but I have heard many critiques of the US's space shuttle program. Yet Buran looks almost identical from a cursory view. Why would the Soviet's independently develop a highly flawed project? This article does a decent job answering that: http://www.popularmechanics.com/space/rockets/a9763/did-the-...

> Why would the Soviet's independently develop a highly flawed project? Probably a few reasons: * At the point of starting Shuttle operations, the flaws of the design weren't as apparent, especially not to general public. * Even though it LOOKS similar, it's actually not all that similar in design. The main difference is that it doesn't actually carry engines (which are the most expensive and problematic part of Shut…

It's not just rebuilding engines it's returning their weight that's a problem. The high temperatures are a result of pressure not friction. A smaller and or less dense craft has a vastly easier time during reentry.

A shuttle actually works fairly well at around 1/5 the size. Lower thermal stress means no tiles. It would have a single ideally swappable engine large on board fuel and no external fuel tank. Still needs SRB's but those actually work fairly well.

Re: China Will Resurrect the World's Largest Plane

#57

Is an aircraft of this size economical, or is it a fuel hog useful only for carrying huge single-piece cargos that smaller aircraft cannot? Is it useful, or is it sheer size-vanity?

This particular aircraft ain’t economical by today’s standards. Here’s some comparison to a popular modern cargo plane, based on public data: https://1drv.ms/x/s!AKpTxXHPN4XIj9tN

As you see, fuel economy is somewhat worse compared to that Boeing.

I don’t think the main problem is size or weight. I think the main one is age. AN-255 is 30 years old, Boeing 747-8 is 6. That’s almost 25 year or progress in aerodynamics and engines development.

Re: China Will Resurrect the World's Largest Plane

#58
Tyler Rogoway (formerly of Jalopnik's FoxtrotAlpha and now writing for TheDrive.com) had a take on China's goals(1). He seems to think that the plane's ability to act as a launch craft is a notable. I've found Rogoway to be a pretty good source of digestable and non-sensational military tech info.

1. http://www.thedrive.com/the-war-zone/5083/why-china-wants-to...

Re: China Will Resurrect the World's Largest Plane

#59
post #56
post #41

Earlier quoted context omitted.

> Why would the Soviet's independently develop a highly flawed project? Probably a few reasons: * At the point of starting Shuttle operations, the flaws of the design weren't as apparent, especially not to general public. * Even though it LOOKS similar, it's actually not all that similar in design. The main difference is that it doesn't actually carry engines (which are the most expensive and problematic part of Shut…

It's not just rebuilding engines it's returning their weight that's a problem. The high temperatures are a result of pressure not friction. A smaller and or less dense craft has a vastly easier time during reentry. A shuttle actually works fairly well at around 1/5 the size. Lower thermal stress means no tiles. It would have a single ideally swappable engine large on board fuel and no external fuel tank. Still needs…

My understanding is that it got fatally compromised as either a 3 letter agency or the pentagon wanted to use it for satellite maintenance/retrieval. Never happened, but it still resulted in a hybrid design that was basically suitable for neither. In the end it may well have continued flying as a kind of "national pride" issue.

Re: China Will Resurrect the World's Largest Plane

#60

Earlier quoted context omitted.

Why not to just buy one aircraft and reverse engineer its engines? What is the problem with just copying exact copy of existing engine?

In this case U.S. government restrictions probably restrict China from buying U.S.-manufactured planes. I doubt Antonov wants to sell its only An-225.

The Chinese buy plenty of U.S. manufactured planes. In fact, in order to convince China to buy large aircraft like the 777, Boeing was more than happy to sign offset agreements[0] that sent a significant portion of manufacturing of smaller aircraft to Chinese subcontractors.

Lest you think I would only throw stones at my former employer, Airbus has been doing that and more. They are actually doing final assembly in China.

[0] https://en.wikipedia.org/wiki/Offset_agreement

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