Shenyang FC-31 / J-31 Fighter Demonstrator

NICE. Looking good. Like a slim version of twin engined F-35.

I thought my post was pretty clear, the modifier follows the subject immediately. For an unnamed Shenyang aircraft, the structural weight is 26.8% of the empty weight of the said aircraft.

by78 said:

The segment also provided a tiny bit more information on the current state of 3D-printing in the Chinese aerospace industry. 3D-printing was first introduced or experimented with in 2003. Further breakthroughs in this field have resulted in a significant reduction in aircraft structural weight, now down to 26.8% of total empty weight on an unnamed Shenynang aircraft project.
Here's the original video:

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On second examination, I'm not so sure about my original translation.

Could someone take a look at the video, starting around 12:53 mark and ending 13:27?

I'm interested to know if the cited figure of 26.8% is the ratio of internal structural weight to empty weight; or is it the ratio of empty weight to max takeoff weight; or is it internal structural weight to max takeoff weight?

by78 said:

On second examination, I'm not so sure about my original translation.

Could someone take a look at the video, starting around 12:53 mark and ending 13:27?

I'm interested to know if the cited figure of 26.8% is the ratio of internal structural weight to empty weight; or is it the ratio of empty weight to max takeoff weight; or is it internal structural weight to max takeoff weight?

Click to expand...

Copying my reply from the J-20 thread.

If I’m hearing this segment right I think we have a false alarm on our hands. As I understand it, that segment is saying that typically the structural weight of the aircraft is usually about 30% of the aircrafts takeoff weight (they don’t say max, so I suspect this is standard), with exceptional cases able to reduce this down to 28%. With 3D printing SAC has been able to reduce the structural weight to take off weight ratio down to 26%. The interviewer even asks if this reduction might be trivial. I think it’s also implied, given how the narration and interview is spliced together, that they’re talking about the J-15, not the J-31.

manqiangrexue said:

I'm sorry, what?? Reduced weight by 26.8% or down to 26.8%?? Cus the former means making a 20 ton aircraft 15 tons but the latter means making a 20 tons aircraft 5 tons LOL. Can't be the latter... The Chinese screen capture only says "We have reached 26.8%..." and the rest is cut off.

Really glad to see this, by the way. This would reinforce the 15 tonne class figure given for J-20 since a 21 tonne aircraft reduced by 26.8% would be 15.37 tonnes.

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No it won't, and yes I am smirking,,, Happy Thanksgiving Brother, and may all of God's Blessings and Love fall on you, and all of my Sino Defense Bros, I do love you guys, yep even you brother.

but dreaming that the J-31 or J-20 weigh 25% less than their contemporaries is just a fan-tasy, and you're right, if it did that would be amazing, but no matter how you close your eyes and wish, or hold your breath, the J-20 is still probably gonna be heavier than the F-22!

by78 said:

On second examination, I'm not so sure about my original translation.

Could someone take a look at the video, starting around 12:53 mark and ending 13:27?

I'm interested to know if the cited figure of 26.8% is the ratio of internal structural weight to empty weight; or is it the ratio of empty weight to max takeoff weight; or is it internal structural weight to max takeoff weight?

Click to expand...

It is a claimed 26.8% percent reduction in the weight of each individual part! which is indeed quite significant, and that overall might indeed result in a 3 to 7% overall weight reduction in the final aircraft. Think Boeings 737 Max, new aircraft do have a performance edge due to what is indeed a game changer.

Before this gets out of hand, the video never said the reduction was 26.7%. Rather, as latenlazy pointed out, for an unnamed Shenyang aircraft, the ratio of its structural weight to its takeoff weight is 26.7%. The original video stated that it's optimal that an aircraft's structural weight be capped at 30% of its takeoff weight. Achieving a 28% ratio is considered very good, and with Shenyang's 3D printing techniques, they were able to shave the ratio down to 26.7%.

by78 said:

On second examination, I'm not so sure about my original translation.

Could someone take a look at the video, starting around 12:53 mark and ending 13:27?

I'm interested to know if the cited figure of 26.8% is the ratio of internal structural weight to empty weight; or is it the ratio of empty weight to max takeoff weight; or is it internal structural weight to max takeoff weight?

Click to expand...

It sounds to me that your initial interpretation was good. They managed to decrease the structural weight from 28% to 26.8% of the total weight of the plane.

When the interviewer made a comment that the decrease might sound a little trivial, the engieneer said that, on a fighter, cutting down even one gram is very significant.

Can we presume that the same process is cutting the weight of the Flankers too ?

Franklin said:

Can we presume that the same process is cutting the weight of the Flankers too ?

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NO!