Chengdu J-20 pictures, analysis and speculation Part I

[Deino]

from the 3. or 4. flight !

 

[flateric]

from cjby.net

 

[Ian33]

Haven't seen a smokey Joe pic like that since the late 60s and the original B-52s lol. Fellas, the pictures are superb; many thanks.

 

[Grey Havoc]

Haven't seen a smokey Joe pic like that since the late 60s and the original B-52s lol.

They were playing to the gallery, methinks.

 

[Deino]

:

 

[Deino]

Actually the J-20 performed today its fifth flight ....

 

[Sundog]

There's a pic of it taking off with a/b at alert5.

http://alert5.com/2011/05/11/photo-j-20-afterburner-take-off/

 

[Deino]

sadly not the complete un-psed photo ... :-*

besides that:

Overscan:
You are right, it has been proved the engine 2001 installed is AL-31, and here is (maybe)new photo

I know that this is at the moment the most widely accepted option but has it beed really proven !!!??

Deino ???

 

[Deino]

Oh my god , the complete J-20-staory is really only a hoax !!! ;D

h t t p ://v.youku.com/v_show/id_XMjU0MzU1NTgw.html

Deino

 

[Deino]

Thanks a lot to "Paralay" ! :-*

 

[Stargazer]

Oh my god , the complete J-20-staory is really only a hoax !!! ;D

h t t p ://v.youku.com/v_show/id_XMjU0MzU1NTgw.html

Deino

Correct link is as follows: (add "http://" before) v.youku.com/v_show/id_XMjU0MzU1NTgw.html
Really a superb R/C model which handles extremely well.

 

[Deino]

The J-20 did two additional flights today !
Reportedly for the first time some kind of maneuvers like rolling and turning !

Anyone with info on duration ... ?

Deino

 

[Grey Havoc]

One of the test flights seems to have had a bit of bother involving a fuel dump. No word on whether it was a malfunction, pilot error, or an emergency fuel dump as part of a larger problem.


http://www.flightglobal.com/blogs/the-dewline/2011/05/video-j-20-dumps-fuel-over-che.html

 

[rousseau]

It is believed a cockpit of J-20

 

[Deino]

Hey ... that bird is duing regular its tests and besides some real crazy maniacs none is still interested in that bird any longer ?!

One of the test flights seems to have had a bit of bother involving a fuel dump. No word on whether it was a malfunction, pilot error, or an emergency fuel dump as part of a larger problem.

http://www.flightglobal.com/blogs/the-dewline/2011/05/video-j-20-dumps-fuel-over-che.html

I don't think that this is a hint for a malfunction or problem ... we've seen the J-10's doing this fuel-dump over Chengdu too (like the brand-new J-10AH's).

 

[TAKHISS]

Good Weather

 

[TAKHISS]

May 14

 

[Grey Havoc]

Hey ... that bird is duing regular its tests and besides some real crazy maniacs none is still interested in that bird any longer ?!

This particular crazy maniac would like all the info and pics he can get. ;D

I don't think that this is a hint for a malfunction or problem ... we've seen the J-10's doing this fuel-dump over Chengdu too (like the brand-new J-10AH's).

In other words, a very bad habit. Where's Greenpeace when you actually need them?

 

[Deino]

This particular crazy maniac would like all the info and pics he can get. ;D

AMEN ! ;D

In other words, a very bad habit. Where's Greenpeace when you actually need them?

Sadly the "green-party" doen't rule in CHina ... at least for now !

Deino

 

[Deino]

Today flight no. 8 from 15:16 to 16:16 h.

 

[rousseau]

A brief for Chinese WS-15 turbofan.
Regretably no translation

 

[Deino]

A brief for Chinese WS-15 turbofan.
Regretably no translation

Can anyone help with a summary or translation besides this "BING-translation" ??

Introduction to Chinese WS15

Turbofan 15 (WS15) grade turbofan 15 named "Fabri" military turbofan engines use Turbo-fan Jet engine turbofan engine type Chief Designer Jiang Hefu national China Research Institute of China gas turbine manufacturer Xian machine engine company/Li Yang Guizhou aviation engine company object WS-15-10 for J-10M (export) WS-15-13 J-13 single general layout of abdominal DSI intake stealth fighter. WS-15-CJ for a study of vertical/short take off landing fighter. (CJ is Chuizhiqijiang Jianjiji letter of the first vertical take off and landing fighter shorthand) WS-15X for double-billing of heavy lead flight test of the stealth fighter.
In the Russia Yu 1992 spring began expand hard negotiations, in after 3 years of saw zhihou, because Russia of economic status is difference, for military research of funding rarely rarely, and because in 92 Minsk maqiulisha meeting ya grams-141 was terminated Hou, P-79 engine no has using object, and no other of fighter using this engine, so "Union" aviation engine research production Consortium (original Paul mansky engine shejiju) of economic status is difference, in this status Xia, June 1995, in the Russia signed has transfer P-79 engine production license of agreement, August 1996, Russia of "Union" aviation engine research production Consortium (original Paul mansky engine shejiju) to China aspects delivery has P-79 engine of full design drawings and the technology information, especially introduced has manufacturing P-79 engine core machine of production device and the production manufacturing technology information. regrets of is for ya grams-141 of P-79B-300 engine vector nozzle technology is no are, then is as a vertical landing fighter of vortex fan engine for pre-inquiry, but this vertical landing fighter with many China yiqian development of aircraft as. (Later, in 1998 when the Asian financial crisis Russia economy were also multiple crises, China not only purchased for ya-g-141 P-79B-300 engine nozzle technology, but also made the Moscow Union of Aero-Engine technology group developed the thrust of 20 tons of R179-300 engine design and P-79M design drawings and technical data. R179-300 engine is the engine for vertical takeoff fighter Jacques 141 research and further development of the R-79V-300 engine. ) In this background Xia, 1996 early, River and Fu collaborative Liu Da ring academician is responsible for organization "95" Defense major background (vertical landing fighter of plan) of pre-inquiry project--a new Vortex fan engine (to P-79 engine for Foundation for depth development) key technology pre-inquiry work, surveying and mapping imitation P-79 engine of core machine, organization completed has P-79 engine of high pressure pressure gas machine, and combustion chamber, and turbine three large core part, proportion of surveying and mapping imitation of work. for theory method, and calculation method and test method of exploration research; to breakthrough advanced part key technology mainly, focus around three large high pressure part, proportion full size test pieces of design and trial and the test to and related of strength, and control, system for comprehensive application research, in three large core part of surveying and mapping imitation in the, bold advocate used has aviation power many frontier design technology results and large application new material, and new technology, to breakthrough has more than 120 more than item key technology.

624 made the Moscow Union of Aero-Engine technology group developed the thrust of 20 tons of R179-300 engine design and P-79M design drawings and technical information, development YWH 130-27 core machine, YWH 130-27 core engine is based on the P-79 engine core engine as the basis for the further development of. CJ-2000 is based on YWH
30-27 core engine as the basis for further development, development WS-15 is the CJ-2000 version of code. (CJ is vertical landing fighter of Chuizhiqijiang Jianjiji letter first a shorthand, 2000 is project began development of time is 2000) 1999 national day Hou, 624 by reference R179-300 and P-79M of engine design programme, launched has to YWH 130-27 core machine for Foundation of improved design programme, in compete for next generation fighter fighter-13 of engine Shi, get victory,, 2000 early official was selected for fighter-13 singles general layout abdominal DSI inlet of stealth fighter aircraft of power plant. The number is WS-15. Named "Fabri" turbofan. superior requires the "WS-15" engine development to fully implement the new military standard GJB241-87 "General specification for aviation turbine air-jet and turbofan engines and full implementation of the structural integrity of the engine framework. At the same time decided to include the development of WS-15 is divided into three phases: three high pressure development of performance parts and the core development research, develop, validate and prototype of the machine. This WS-15 project development, this is my first time to follow the "key technology breakthroughs-advanced basic research-development-model-validation machine parts-core machine" by this development model of turbofan engine development work, so it can be said to be a milestone significance! Comprehensive development work began in early 2000. (Sliding the machine validation machine was given in 1997, in 1999 due to financial reasons forced to abort. Actually is for WS-15 way and horse, and not because WS10 engine or due to funding causes) from recently held of China gas turbine Institute (624 by) work will Shang was informed that, in China itself development of thrust thrust-weight than for 9 of turbine fan aviation engine of core machine CJ2000 Yu on April 14, 2005 first ignition success Hou, thrust-weight than for 9 of turbine fan aviation engine of core machine has Yu July 2005 early in Taiwan frame running test Shi, various performance full reached has design index, speed push to ground highest speed (conversion speed 102.2%)-----"e eyebrow" aviation engine of technology validation machine in May 2006 first Taiwan frame running test success. This indicates that China's autonomous development of Aero-Engine and on the road to achieve a historic leap forward, in the development of China's fourth generation midsize fighter took a solid fundamental step on the journey. March 2007 prototype machine bench running successfully for the first time, is expected in June 2009, "Fabri" engine prototypes will complete the FRET (flight identification before the pilot phase), the end of June 2009 with J-13 first flight successful. for 60 anniversary of the motherland and offered soup gift. expected to be completed March 2013 engine design type testing. Stereotypes of July 2014 production engine, installed "Fabri" aero-engine of fourth generation single medium fighter (J-13) in 2013, with initial operational capability.

In accordance with the aircraft mission requirements, "Fabri" choosing higher cycle parameters of aeroengine turbine inlet temperature, moderate overall pressure ratio of culvert road and lower than. Used of technology main has injury capacity limited and efficient of wide string leaves, and three dimensional viscous leaves turbine design method, and overall leaves disk structure of fan and pressure gas machine, and single crystal gas cold turbine leaves, and powder metallurgical turbine disk, and brush type seal strict, and resin base composite outside culvert machine casing, and overall type Afterburner combustion chamber design, and ceramic base composite nozzle regulation tablets, and ternary vector nozzle and has fault diagnosis and State monitoring ability of double more than of type full digital type electronic control system. Engine is composed of 10 units.
"Fabri" structure and system of turbofan engine inlet ring, air inlet casing for all titanium structure. With 18 variable camber inlet guide vanes, the front for radial support plate, rear adjustable parts, edge is to air from the high pressure compressor ice. Fan 3-stage axial-flow. Wide-chord fan blades of solid titanium alloy. 1th stage fan blades with the wide chord design, removable fan blades, with a middle boss. 2nd and 3rd stage fan to simple linear friction welding technology of welding into a blisk structure. Fan casing is a ring structure, the fan rotor made of removable, the 2nd-level disc front and rear with drum loops, and respectively, 1th disk connectivity. Boost almost 4.01. 3-level design of stator and rotor are three-dimensional flow. 6 stage axial-flow in high pressure compressor. Boost than 7.16. Level 3 before rotor disc structure as a whole, are forging on with electrochemical machining. 3 after stage rotor blades through Chevron rabbet and disc connection. Titanium alloy for the first 3 stationary blade material. Rotor for hybrid structure of electron beam welded and bolted, using three-dimensional flow design. Stator part of inlet guide vanes and the 1th, 2 stationary blade adjustable level 3 disk made of high-temperature titanium alloy before, both before and after the 2nd-level disk with drum loops, and respectively, 1th disk connectivity. Di4~6ji plate made from nickel-Base Superalloy powder metallurgy, electron beam welding is a body, with long bolt front and 3rd-level disk connected together. Opposite to the mediation case as a whole and for titanium alloy compressor casing, a borescope peep hole, for the observation of rotors and other parts.

Combustion chamber short concentric type. The flame tube uses the laser drilling the vesicular structure to carry on cooling. The flame tube double-decked floats the wall type structure for the whole, the outer layer for the whole ring-like shell, uses the binary channel spray nozzle, the fuel oil spouts after 22 bipyramid spray nozzles and 22 eddy cups and atomizes, realizes the smokeless combustion, has the even export temperature field. High pressure turbine single stage axialflow type. Uses the domestic second generation of unit crystal turbine blade material, the heat insulation coating and the advanced cooling structure. The single stage axialflow type, does not bring the crown. Uses gas blanket cooling to add the impingement cooling way. The rotor blade and the stator blade material is the domestic second generation of unit crystal material, on the leaf blade has the physical gas phase deposition heat insulation coating. The engine case inside lining fan-shaped section carries on the tip clearance control through the cooling air. The rotor blade and the guide apparatus may replace alone. The turbine wheel part uses the haploid structural design, after turbine rotor, guide apparatus, turbine casing, turbine wheel the engine case and the bearing engine case and so on five modules compose. Low pressure turbine single stage axialflow type. With high-pressure spool to extension. The hollow air-cooled rotor leaf blade, brings the crown. The rotor blade may replace alone, the stator blade may partition the replacement. Still had used the low pressure turbine guide apparatus. The low pressure turbine wheel disk center opens has the pocket, with the aim of installing high-pressure spool's rear bearing (intermediary bearing). Afterburner integral type. Uses the radial direction flame stabilizer. The flame stabilizer is composed of 1 “V” the shape center flame stabilizer with 36 radial direction stablers. The radial direction stabler uses the ventilator air cooling. The thrust augmentation tube body uses is flame-resistant the titanium alloy to reduce the weight, tube in vivo does has the heat insulation sleeve, outside both's slit average crosses contains the air to carry on cooling to the tube body, the center ring-like flame stabilizer makes 12 sections along the circumference, may the free expansion, whole set flame stabilizer be possible, in the engine installs under airplane's condition carries on the replacement, the tail pipe entire journey adjustable restraining - expansion type, uses three Yuan vector nozzles, may make ±25° the deflection in the pitching direction. From +25° to - 25° the traveling schedule in only needs 1.5 seconds. Uses in adjusting the airplane pitching flight attitude. Is loaded with the advanced ceramic base compound materials tail pipe to adjust the proglottis. The control system thrust force and the vector by the double redundancy entire jurisdiction digit electronic control system control (FADEC), according to the ventilator rotational speed and the core machine-pressed ratio adjustment engine work, have the failure isolation function. [engineering data]Biggest thrust augmentation thrust force (daN) 16186.5 middle thrust force (daN) 10522 thrust augmentation oil consumption (kg/daN/h) 2.02 middle oil consumption (kg/daN/h) 0.665 thrust ratio 8.86 air flow (kg/s) 138 vectored thrust compared to 0.382 total supercharger ratio 28.71 turbine wheel intake temperature (℃) 1477 most large diameter (mm) 1.02 length (mm) 5.05 quality (kg) 1862.3

Deino

 

[Trident]

Based solely on plausibility, here's what I make of what seem to be the the technical characteristics of the engine at the end of that article:

Reheated thrust: 161.865 kN
Dry trust: 105.22 kN
Reheated TSFC: 2.02 kg/(kgf*h)
Dry TSFC: 0.665 kg/(kgf*h)
Thrust/Weight ratio?: 8.86
Air mass flow: 138 kg/s
Bypass ratio: 0.382
Overall pressure ratio: 28.71
Turbine inlet temperature: 1477°C (= 1750 K)
Inlet diameter: 1.02 m?
Length: 5.05 m?
Dry weight: 1862.3 kg

IF the above is correct and IF the article is factual, the WS-15 rather resembles a F414-EDE (6-stage HPC) scaled up to F119 thrust levels. Not a bad engine, with some margin for higher thrust by increasing turbine inlet temperature.

 

[Deino]

Here a nice summary at the CDF made by "pierrotlefou"

Rough guesses?

First paragraph basically says that:
- WS-15 (named "Fabri" ?? ) is designed by Jiang Hefu of China Research Institute, a subsidiary of the gas turbine manufacturer Xian machinery company and Li Yang of Guizhou aviation engine company
- There are four versions of the engine being developed:
1) WS-15-10 is for the J-10M, which is the export version of J-10
2) WS-15-13 is for J-13, a single-engined stealth fighter with an abdominal DSI intake (similar to the J-10, then)
3) WS-15-CJ is for a VSTOL fighter under development, where CJ is abbreviation for Chuizhiqijiang Jianjiji
4) WS-15X is to be used in a twin-engine configuration for China's stealth fighter's flight testing (implying that the engines on J-20 already are WS-15s?)
- Negotiations for tech transfer began in Russia in 1992
- In 1992 also, the Minsk aircraft carrier was decommissioned, resulting in termination of the Yak-141 VSTOL fighter program
- As a result, the Tumansky R-79 engine designed specifically for use by the Yak-141 became useless, as no other plane in the world uses this engine.
- Because of this and economic difficulties plaguing Russia, in 1995 Tumansky agreed to transfer technology for licensed production of the R-79 engine in China
- In 1996 the full set of drawings and technical data, including tooling equipment and manufacturing processes were transfered to China
- Unfortunately, at this time the technology for the thrust-vectoring nozzles for the R-79 engine was not transferred as well
- However, in 1998, due to the Asian Economic Crisis affecting Russia, China was able to purchase not only the technical details of the R-79V-300 (note: Cyrillic P = R, B = V) engine's TVC nozzle, but also asked Tumansky to develop a 20-ton (19.6 kN) thrust R-179-300 engine and hand over the R-79M engine's technical data.
- Based on this, Jiang Hefu and Liu Da started in 1996 to develop for Defense Research Institute "95" (?) an engine based on the R-79 core.
- Rest of paragraph lists what they did and their achievements.

On the second paragraph:
- After 624 (Institute?) got Tumansky working on the 20-ton-thrust R-179-300 engine and R-79M, they developed the engine into the YWH 130-27 engine to be used on the CJ-2000 (presumably the VSTOL fighter design).
- They then entered the core of the YWH 130-27 into the competition for the J-13 single-engined stealth fighter project and won.
- This victory meant they then had to develop the the core of the YWH 13-27 into the WS-15 turbofan for the J-13 fighter program.
- The military named the WS-15 engine "Fabri" (??) :what: and required them to design the engine based on the new military standard GJB241-87 (Guo Ji Biao ?? - came across quite a few of these in my line of work) "General specification for aviation turbine air-jet and turbofan engines and full implementation of the structural integrity of the engine framework"
- Next the author talks about the phases of development work, but I can't figure out whether his first sentence agrees with his second sentence or he's trying to say the WS-15's development work didn't follow the standard procedure and thus had historic significance.
- Interestingly he said that the engine validation phase started in 1997 but they were forced to abort in 1999 because of financial reasons, taking pains to state for the record that the development of the WS-10 had nothing to do with the decision to delay the WS-15 project, nor was their funding cut.
- It turns out that on April 14, 2005 China's 624 Institute successfully performed ignition test of a turbofan engine with greater than 9 thrust-to-weight ratio - in this case the engine developed for the CJ-2000 project (YWH 130-27?).
- By July of 2005, the Taihang (I'm assuming Taiwan is a mistranslation) platform (also?) achieved >9 TW ratio and fulfilled all its performance requirements, reaching its highest design speed (?).
- Test of the first Taihang engine platform completed in May 2006
- What is more interesting is that in March 2007 another engine (WS-15?) finished its prototype bench test and the author states that by the end of June 2009 the prototype J-13 had made its first flight successfully (whuddaheck? :huh and apparently someone got soup for the 60th anniversary of the PRC in October 2009 :screwy:. Hey, how come this is the first we've heard about this?
- Anyway, the author then proceeds to confidently say that the engine development for the J-13 should be completed by March 2013, with production stereotypes ready by 2014. J-13 itself is supposed to reach IOC by 2013.

Will continue later if no one else takes up the challenge. However, some interesting points here:

A) There is a J-13?

B) If the WS-15 engine is based on the R-79 and its TVC mechanism is based on that of the Yak-141, then implementation would be rather interesting. The Yak-141's TVC nozzle is the same type used on the F-35B (Lockheed also bought data from Yak) and is unique in that it can turn 105 degrees and has no axial actuators. It is actually composed of three pieces of a tube cut diagonally like this: =\=/= that rotate against each other to bend the nozzle. This design also has the advantage of being able to form a proper seal in the flow path. However, in the F-35 turning the nozzle actually requires the skin of the plane where the nozzle is enclosed to peel open. After all, this nozzle is only meant to be used to transition to and from vertical flight. How an air superiority stealth fighter is supposed to implement this in turning combat is beyond me.

C) Who is doing the J-13? (Assuming it exists) Xian and Guizhou aviation engine companies are cooperating on the engine. Does this mean either Xian or Guizhou aircraft manufacturers will build the plane?

Actually I have that strange feeling that there's something "fishy" ... .

As such I would say it sounds too good (performance wise) to be true and as far as I know the WS-15 is an indigenous design - maybe with Russian assistance as some sources suggest - but not based on a Russian design.

Deino

 

[Trident]

Yes, the jury is still out on the credibility of the document. That said, it makes sense for the HPC to have six stages if it is based on the R-79 core and the TVC nozzle story is basically plausible as well - after all a version of the engine was intended for that CJ-2000 VSTOL project. Alternatively, the nozzle in question may not actually be that of the R-79V-300 but either the axisymmetrical 2D TVC of the R-79M or the rectangular one from the R-179-300 instead. The time frames mentioned sound about right too.

I guess the real indicator about the legitimacy of this document is whether the J-13 and CJ-2000 designations hold up to scrutiny.

The R-79 family has always been quite fascinating to me, superficially they seemed unimpressive due to low overall pressure ratio and high weight. However, it turns out the weight figure I had seen was not the dry weight standard generally quoted for other Russian engines and that on a level field the R-79 was quite competitive. Similarly, an OPR of 22 is pretty damn good when you use just 7 compressor stages to get there!

 

[Deino]

Hmmm ... Flight no. 9 on 1. June and no. 10 on 2. June ... sadly no additional info ! :-[

 

[Deino]

Reportedly a taxi-test from yesterday with the air-brake deplyed for the first time (if not faked again)

Deino

 

[flateric]

it's only me who thinks that brake inner structure seems too overdue?

 

[chuck4]

The air brake does look overly thick, as if it had a fuel tank or something built in. But note the wings appear to have twist towards the tip, which is unexpected in a canard design?

 

[Grey Havoc]

The air brake does look overly thick, as if it had a fuel tank or something built in. But note the wings appear to have twist towards the tip, which is unexpected in a canard design?

Or a ECM system/sub-system of some sort?

 

[Trident]

The air brake does look overly thick, as if it had a fuel tank or something built in.

It does look quite beefy, but not overly so - consider:

http://cdn-www.airliners.net/aviation-photos/photos/6/2/3/1831326.jpg

http://www.airforceworld.com/fighter/gfx/su27/su27_airbrake.jpg

For me, the biggest surprise is that it has an air brake at all. Ok, with a single tail aircraft like the J-10 using the control surfaces to perform this function can get rather non-trivial for the FCS (kudos to Dassault for sussing that one out on the Rafale!) but with twin tails it should be a fairly straight forward job (as seen on the Su-35).

But note the wings appear to have twist towards the tip, which is unexpected in a canard design?

Strictly speaking it's mostly camber rather than pure twist, but either way it's not at all unusual (in fact, it's almost the norm) for (canard)deltas.

 

[SOC]

it's only me who thinks that brake inner structure seems too overdue?

Not necessarily. Look at the white "box" on the underside of the airbrake. The edges are angled, suggesting that they fit into a similar cavity in the fuselage. This might help with ensuring a flush fit with the external surface?

 

[rousseau]

New photos found
Not so valuable but collecting......

 

[mithril]

here's a question you guys might be able to answer. have any of the J-20 pictures shown thrust vectoring?
i keep reading (western) articles where the planes "thrust vector ability" and all the other features are hyped up.
yet none of the pictures i can find seem to show any sort of off-axis mobility for the nozzles.

it's getting to the point that i'm figuring that the talk of thrust vector on the J-20 is just people assuming that since the F-22 and T-50 have thrust vector, the chinese J-20 would automatically have it too.

 

[Firefly 2]

From the pictures it would seem that these prototypes have no TV. I remember that the SU 37's nozzles would drop when not powered... I'm no expert, by no means. But I just don't see any obvious indicators that TV has been applied to these planes.

 

[mithril]

which makes you wonder. even if this is just a proof of concept technology demonstrator, not a prototype for a production aircraft, you'd expect that if they planned TVC for future planes they'd build it in.

 

[sferrin]

Seems pretty refined for a demonstrator, not to mention large. Which begs the question, where are the demonstrators?

 

[Steve Pace]

The smaller F-22 is a fighter-bomber so why can't the larger J-20 be one too? -SP

 

[Grey Havoc]

The smaller F-22 is a fighter-bomber so why can't the larger J-20 be one too? -SP

The YF-22 was (originally intended as) a fighter-bomber. Probably would have been a very good one indeed. The F-22A is more of a kludge in this role, although still probably more capable than a lot of aircraft designed from the outset as such.

 

[rousseau]

There is a slightly sharper angle of view on the F-111.......