Chinese Engine Development

ACuriousPLAFan said:

Let's put things into perspective.

If the H-20 really is meant to employ turbofan engines of the D-39KP-2/WS-18-category (whether than be WS-18 or a brand new WS-XX model), and assuming that the H-20 sports the same number of engines as the B-2 - Then it is reasonable to expect that the H-20 would be bigger and heavier than the B-2, due to the greater cumulative thrust available to the H-20 compared to the B-2 (468 kN versus 340 kN).

In addition, there are the benefits of fuel efficiency as well. Namely, the larger the bypass ratio, the more fuel efficient the engines are. This translates to:
1. Increased range and combat radius; and/or
2. Increased airframe volume available for internal weapons bays (IWBs), fuel tanks, sensors, avionics and computing systems.

As for the difference in fan diameters between the F118 and the D-30KP-2/WS-18 - That's about one 30-centimeter/12-inch ruler, for visualization purpose. Moreover, if the H-20 is indeed larger than the B-2 (which I've heard rumors of this being the case), then there should be enough airframe volume to embed the engines, plus sufficient forward cross-sectional area of the aircraft body to hide the engine fan blades.

Otherwise, there could be some compromises as a result - However, if the PLAAF higher-ups deem the tradeoff from such downside is worth the overall performance and capability of the H-20, then it'll certainly get the green light.

TL; DR -
1. High-bypass engines on a large, flying-wing VLO platform shouldn't be too much of a problem, provided that they can be designed and engineered properly; and
2. The aforementioned high-bypass engine very likely isn't the same as the ones we are typically associated with (e.g. WS-20, CJ1000A, CJ2000 etc).

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Side note: While lacking rather conclusive/authoritative information for the time being, I don't think we should be surprised should the B-21 be able to achieve long enough ranges, if not comparable to the B-2, provided the claim of the B-21 being powered by PW9000 engines with bypass ratio of ~4 is accurate, compared to the ~1.3 bypass ratio of the F118 engines.

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Nx4eu said:

15,000-16,000km unrefueled range sounds about right. Given it's been speculated to be powered by 4xWS-18/D-30KP-2 if we apply the numbers and compare them to be similar to B-2 so about a thrust to weight ratio of ~0.205. The MTOW should be around 260 tons and the max fuel capacity around 118 tons. Applying a similar L/D ratio to the B-2 of around 20 would get a Max range of 16,000 km. This would make the H-20 the second largest in service bomber in the world at MTOW of 260 tons behind the Tu-160 with a MTOW of 275 tons. This is just speculative of course.

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by78 said:

Nice images of the WJ-6 turboprop.

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Tomboy said:

If this new request and the WS-35 are both meant for H-20. IMO that is very bad news for the project, WS-35 seems to be in the stage of building the first prototype while the new request shows that H-20's intake config is still in the research/design phase. No way in hell is this thing gonna take it's first flight before Zhuhai next year as Cute Orca said.

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mack8 said:

That is exactly what i was going to ask, the year of the paper. Hopefully we'll get to see the H-20 in all it's glory before Zhuhai 2026.
What year is the paper referring to WS-35?

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sunnymaxi said:

”Matching Methodology and Aerodynamic Stability Assessment for Large-Offset S-Ducts with High-Bypass-Ratio Turbofans”.

that is from year 2022..

here is the full image of tender.

this is definitely related with H-20 program and from 2022.. indicate H-20 project going as per schedule. Orca is right

View attachment 150455


Note - WS-35 is not related with H-20 bomber.

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Tomboy said:

Ah, thanks

Timelines matches up much more perfectly now.

Is it right to assume right now we have:
H-20 Project: Nearing first flight
Y-30(?) Medium transport: In progress
Potential Superheavy transport: Speculated

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sunnymaxi said:

1. yeah we can expect H-20 first flight in next 16-18 months as per Orca.

2. Y-30 largely depend on PLAAF. right now there are too any important projects. but as per the source project accelerate.

3. this one is really interesting, if you read my old massages, AECC Shenyang is also working on 25+ tons thrust WS-20 successor. now this AECC Xian tender about WS-35. these things indicate program might be in research phase. they also did simulation testing of large aircraft for next gen AEW&C.

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