Forum: Technology

The Sukhoi T-50 is supposed to have an A.E.S.A. radar along with I.R.S.T. see this aviationweek article. http://www.aviationweek.com/aw/blogs/defense/index.jsp?plckController=Blog&plckBlogPage=BlogViewPost&newspaperUserId=27ec4a53-dcc8-42d0-bd3a-01329aef79a7&plckPostId=Blog%3a27ec4a53-dcc8-42d0-bd3a-01329aef79a7Post%3a8f209d80-8213-4309-b93b-e904873c0a0a&plckScript=blogScript&plckElementId=blogDest

Mock up of the radar (and WHY does that fuzz on the base remind me of a 1970's Cutlass I used to own)? Rolling Eyes

From AviationWeek.com,"Also on show were models of the T-50's two IRST sensors—here the frontal IRST (or KS-B), with coating aimed at reducing its radar return". Now without starting a flame war, is it just me or wouldn't that I.R.S.T globe adversely affect the stealthiness of the Sukhoi T-50?

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Quote:

wrightwing wrote:

milosh wrote:

@ultor

So what? If 117 can push armed PAK-FA to 1.5mach without afterburner then I really dont see problem.

The big question is whether the 117 engines can do that, or whether this capability won't be realized till the new engines arrive. We'll just have to wait and see as the flight testing continues.

Interview May2011 - Victor Chepkin - Chief Engine Designer
For military aircraft, we have created two engines - one for the aircraft, like Su-35 ", the second - for the Russian aircraft 5 th generation of T-50". The first - is "117C" - is mainly intended for export. He is more simple in terms of aerodynamics, and most importantly - targeted for aircraft with conventional arms, suspended on pylons outside the fuselage, with no strong constraints on dimensions. Such schemes for example are used on 4-th generation aircrafts , exported to India and Malaysia.

The second engine - is "117" - though only differ by one letter in the title, much more advanced engine - this is a real engine of the 5-th generation. From the rivals can sometimes be heard the 5-th generation engine should be with such a blade, such and such materials, high-speed rotors, and you do not have this ... None of this is all just ways of achieving the goal. A single goal - increasing specific thrust, ie the ratio of thrust to its weight. For example, the first jet engine Arkhip Mikhailovich Lulka weighed 1350 kg and had the same thrust, that is, its specific thrust is equal to 1. The 4 th generation engine , "AL-31F, has already managed to achieve specific thrust of 8.7, and on a 5 th generation, the figure is 10.

The new engine delivers a supersonic speed without afterburner mode. What it gives? If before the fighter was flying to the target with the speed of 700 km / h, now - it is twice as fast.

Our "117" today is already flying on two T-50s. For the company it is quite a major achievement, a large move forward. Although it never was easy. We also have new ideas, we can boast some good groundwork. What is needed in the field of military aviation - the beginning of this mass production? To protect such a large country like ours, from a serious attack the number as 500-1000 aircrafts is needed . For this needed orders, money, production infrastructure.

Q - What are the new challenges encountered when creating the plane 5 th generation?

A - There are thousand problems to solve . Say, for reducing the radar visibility "T-50 has a scheme with an internal arrangement of weapons, so is becoming increasingly important problem of reducing its size. And that means new weaponry has to be developed and put into service , but since it has low volume, it must be highly accurate. It is therefore necessarily need a fully functional GLONASS. The American GPS, for obvious reasons is not suitable, since in times of crisis they will disable it, like during the Ossetian-Georgian war, would impose an artificial shift in the coordinates of 300 km. Also is needed to be known exactly, how do you shoot, so should be a modern mapping system. The missile itself should be stealthy . Such weapons are now manufactured, and all this affects the design of the engine. The work is proceeding according to plans ... In general, in my opinion, the plane turns out good, no worse than the American "F-22".

Q - By the way, if we compare the T-50 "with the" F-22 ", Western sources say that the T-50" is much behind in infrared engine visibility in the rear hemisphere.

A - We're working very intensely, to reduce the infrared and radar visibility, and were twice as better performance in comparison with the "F-22" (at least for those data that are published and which I have).

Q - In the difficult years for the Russian aircraft industry, aircraft building companies that produced military aircraft survived by exports, especially in China and India. Today, the Chinese have copied our Su-27 "and are ready to sell it on world markets at dumping prices. Not whether as a result we lose our traditional markets of combat aircraft?

A - We dont, because such an aircraft as we have, the Chinese have no and will have no in visible prospective. They say that they have made a 5-th generation plane, but one can say anything ... Their best engine was copied from our "AL-31F. And we produce 5-th generation engines , and they are in all of their parameters of thrust, specific fuel consumption correspond to the 5-th generation. I opened the secret and say that we actually already have two 5-th generation engines. The second, which is now conventionally called the "Type 30", has already been tested in flight on the fighter T-50 ". In the future it probably will give the name of "AL-...." According to its parameters it a 15-25 percent better than "117".

Q - You can hear that the 5 th generation engine of a plane is not as important as its electronic filling ...

A - If you compare the share of the motor and electronics to provide the functionality of combat fighter, then I, as you know, though being a minder and a patriot of the industry, yet I must admit that electronics "weighs" is much higher. Without a doubt. That's why a little better, or slightly worse engine - has no special meaning. But, if the engine parameters are much better, as we have done on the "117" (25 percent), the performance characteristics can be seriously improved, even due to increasing the allowed weight of the aircraft.

The engines ready and under development.
Ready - 117s for SU-35 - Reported - 142 kN (32,000 lb) of thrust with afterburner
Ready - 117 for PAK-FA and in Prototype - [25 % better than AL-31F - 123 kN (27,600 lb) with afterburning] - Add 25% = 154kN (35,800lb)
Being Tested and under Development - Type 30 for PAK-FA (15 to 25% better than 117) Add 20% to above - 177kN (41,170lb)

It has been reported the main delay with there ultimate 5th generation engine - the AL---? [Originally the AL41F] whose design was started in the 80's was designed for a larger 5th Gen Aircraft than the T-50.
In the interim they have simply incorporated key parts of that development into the [117s]. The result is the new engine [117] - there interim Fifth Generation engine.
The task now is to reduce the size of the AL41F. Maybe by 2017 as previously reported it will be proven up and ready. Not an impossible task if they have flight tested it on the T 50 as he says above.

USA - F119 - Reported - 35,000 lb (156 kN) (with afterburner)
USA - F135 - Reported - 43,000 lbf (191.35 kN) max, 28,000 lbf (124.6 kN) intermediate
YF120-? - 40,000 lbf; 25,000 lbf without afterburner

rkap wrote:

The engines ready and under development.
Ready - 117s for SU-35 - Reported - 142 kN (32,000 lb) of thrust with afterburner
Ready - 117 for PAK-FA and in Prototype - [25 % better than AL-31F - 123 kN (27,600 lb) with afterburning] - Add 25% = 154kN (35,800lb)
Being Tested and under Development - Type 30 for PAK-FA (15 to 25% better than 117) Add 20% to above - 177kN (41,170lb)

It has been reported the main delay with there ultimate 5th generation engine - the AL---? [Originally the AL41F] whose design was started in the 80's was designed for a larger 5th Gen Aircraft than the T-50.
In the interim they have simply incorporated key parts of that development into the [117s]. The result is the new engine [117] - there interim Fifth Generation engine.
The task now is to reduce the size of the AL41F. Maybe by 2017 as previously reported it will be proven up and ready. Not an impossible task if they have flight tested it on the T 50 as he says above.

USA - F119 - Reported - 35,000 lb (156 kN) (with afterburner)
USA - F135 - Reported - 43,000 lbf (191.35 kN) max, 28,000 lbf (124.6 kN) intermediate
YF120-? - 40,000 lbf; 25,000 lbf without afterburner

Hey they're only 10-20 years behind..... the YF-119 and YF-120 started flight testing in 1990, and the JSF119 (precursor to the F135) flew in 2000.

But how long do the -117 engines last? TBO? How many overhaul cycles can can be performed before the engine is considered 'life expired' (AKA - Junk)

I remember how the MIG-25, and it's massive Tumansky turbojets pushing it beyond MACH 3 struck fear into the USAF and designers of the F-15, prompting the Eagle's Vmax to be MACH 2.5 (At great expense to the US Tax-payers...)

Then it was then found that MiG-25 flights over MACH 2.8 would cause the engines to self destruct....

So the MiG-25 was only good for one max-performance flight!?! How long could the old USSR sustain combat operations if it were changing 50%-75% of the Trumansky R-15s on a daily basis?

The people at PW who assisted with the 'inspection' of the Tumansky R-15B said they 'were junk' (That was a first hand discussion BTW.)

The eastern engine designers have never been able to produce an engine with the same durability (TBO) and power ratios as the west. One of the reasons western jet engines are on the top of most eastern espionage lists.

l believe these engines are credible when I see it operationally. When there are more than a handful of prototypes flying, say an entire fighter wing or two filled with aircraft fitted with these -117 engines. I'm not saying they don't exist, they obviously do; and I'm not saying they're a good reliable engine. But until an engine becomes operational, it's nothing but a technology demonstrator or prototype.

Two Cents

TEG

TEG - give me an upgraded F119 increment and I'll do what I can to get NASA test a modified F-16XXL. Thumb

A plan B of sorts... let's form a consortium to buy T-50 frames integrated with the PW and similar known avionics?

Quote:

Test engine for the PAK FA are successful
Engine for Future Aviation Complex tactical aircraft (PAK FA) is at the stage of preliminary tests that run successfully. ITAR-TASS news agency reported today a program manager for the engine, General Designer im.Lyulki SEC (the Moscow branch of NPO "Saturn"), Yevhen Marchuk.
"The preliminary stage includes conducting bench and flight tests. This is the most labor-intensive period, both in time and in money. Some elements of what is sold in long-term engines of the first stage (product 117) was borrowed from developments in the creation of the engine for the 117C Su-35 fighter. In particular, design methods and calculations, processing technology complex structural elements. In turn, the engine 117C for 80 percent. consist of new parts, in comparison with the last time engines to modern fighter jets (AL-31F). For the engine developed by the latest automatic control system. For the first time it will be built on the Russian element base. Architecture building a system, the control algorithm it - as Russian. We want and cell base was Russia, though we have a whole list of permits for the use of overseas bases, "- said chief designer.
According Marchukova, made ??"more than 20 engines" for the PAK FA. "The engine is fully confirmed in bench mode. By the end of this year, will assess the technical specifications for flight mode" - he said. "By 2013 we should go for state tests," - said the chief designer.
Referring to media reports about the aborted takeoff PAK-FA in the final day of the MAKS-2011, Marchuk said: "Aircraft engine - this is probably the hardest thing in the engineering of the product. The price is very high as the error on the financial costs and in terms of defense state. Therefore, when the slightest deviation from the standard modes of engine test pilot must stop the flight, which was done. Although in previous airshow days, the engine worked perfectly, and the T-50 met all scheduled flights without any problems. carried out by the analysis revealed deviations in the automation engine, which led to the surge. examination showed that the engine is not damaged and the plane through the day will be ready to continue the flight test. "

And here is video of that failure:

http://www.youtube.com/watch?v=RoXqG45ThYA

TEG can you share your thoughts about this problem?

Double post

That_Engine_Guy wrote:

Hey they're only 10-20 years behind..... the YF-119 and YF-120 started flight testing in 1990, and the JSF119 (precursor to the F135) flew in 2000.

But how long do the -117 engines last? TBO? How many overhaul cycles can can be performed before the engine is considered 'life expired' (AKA - Junk)

I remember how the MIG-25, and it's massive Tumansky turbojets pushing it beyond MACH 3 struck fear into the USAF and designers of the F-15, prompting the Eagle's Vmax to be MACH 2.5 (At great expense to the US Tax-payers...)

Then it was then found that MiG-25 flights over MACH 2.8 would cause the engines to self destruct....

So the MiG-25 was only good for one max-performance flight!?! How long could the old USSR sustain combat operations if it were changing 50%-75% of the Trumansky R-15s on a daily basis?

The people at PW who assisted with the 'inspection' of the Tumansky R-15B said they 'were junk' (That was a first hand discussion BTW.)

The eastern engine designers have never been able to produce an engine with the same durability (TBO) and power ratios as the west. One of the reasons western jet engines are on the top of most eastern espionage lists.

l believe these engines are credible when I see it operationally. When there are more than a handful of prototypes flying, say an entire fighter wing or two filled with aircraft fitted with these -117 engines. I'm not saying they don't exist, they obviously do; and I'm not saying they're a good reliable engine. But until an engine becomes operational, it's nothing but a technology demonstrator or prototype.

Two Cents

TEG

There’s also some inaccuracies here. It’s tough to sift through the various numbers between RuAF’s classification and “Sukhoi enthusiasts” postulations; it’s all quite confusing. Most reliable sources cite the project 117 (AL-41F1) as having 33,000lbs static thrust which is what the jets are flying with right now. The ultimate PAK-FA program goal is for an engine in the 39,000lb class, which is about where the F119 is currently. This of course tells us nothing about performance at altitude and mach, what the SFC is and as you mentioned TBO.

On top of this the T-50 is being endowed with all sorts of suspect parameters. For instance despite being apparently roughly 5-10% larger than the F-22 in basic cardinal dimensions it will supposedly come in 10% lighter. On top of that it has two giant holes on the longitudinal axis and carries some 20% more fuel. Yeah right…. No doubt the Russians will make a great jet, but when I see claims such as this I always want to know what, if any of theses characteristics are tactically significant?

milosh wrote:

And here is video of that failure:

http://www.youtube.com/watch?v=RoXqG45ThYA

TEG can you share your thoughts about this problem?

Two possibilities here.

Better view here not time distorted, look at 02:15

http://www.youtube.com/watch?v=rYks9di8oB0

1 - "AB blowout / Compressor Stall" - The afterburner (AKA, Augmentor or Reheat) didn't light properly or as scheduled by the engine's control system. The result was an explosive combustion that sent a shock up through the engine causing the engine to compressor stall (AKA, surge or stall)

2 - Compressor Stall - If the engine was not in AB then it was likely just a compressor stall. Can be caused by many things, but likely an issue with the engine control system, or a sensor of some type.

In the news article above it talks of 'surge' which both cases above include, but the initial large flash seems to be an AB-Blowout, (Notice it's a larger fireball) then the second flash the resulting 'second' surge caused by the first. It's not uncommon for stalls to occur in multiples; 2 3 or 4 times in a row before the engine can recover automatically or the operator reacts.

Example @ 00:20 - http://www.youtube.com/watch?v=mQNUrYoFM2E

Example - http://www.youtube.com/watch?v=jFiaT1yIKOM

Answer your question milosh?

TEG

Here's a top view of the PAK-FA T-50

You can see how the engines "toe in". Remains to be seen how stealthy the final model is.

That_Engine_Guy wrote:

Answer your question milosh?
TEG

Excellent answer Cool

Glad i could help... TEG

[quote="BDFBut how long do the -117 engines last? TBO? How many overhaul cycles can can be performed before the engine is considered 'life expired' (AKA - Junk)
The 117S - NPO Saturn says - Assigned life 4,000 hours and an MTBO of 1,000 hours.
Don't go on about the Mig25 - a quick interim upgrade of a disposable Cruise Missile engine. The Russians knew its limitations and never denied them. That comparison is a bit like those who rave on about F15's taking out downgraded and outnumbered Mig23's and Mig25's. They should! easily. A good comparison would be how they would go against {Russian] Mig31's in equal numbers and with equal support.

Quote:

There’s also some inaccuracies here. It’s tough to sift through the various numbers between RuAF’s classification and “Sukhoi enthusiasts” postulations; it’s all quite confusing.

I agree,it all gets confusing but information from official Russian sources is far more reliable than a lot of the guesses and biased opinions on these forums - all I did was take the older Al-31FP figure of [123kN - Wet]- reasonably well established now - and work from there by adding 25% as stated in the interview. That gives the figure of 154kN for the 117 - also stated last year by one of the Chief Designers at Sukoi.
One thing is obvious they have a Motor for the Pak Fa and the time to make sure it is reliable. It is also feasible the ultimate motor could be ready in 5 to 6 years. If they were confident enough to test it in a valuable prototype it must have been tested reasonably well.
Putin said 2017 for the final motor last year. He normally is very honest and pragmatic.

pak fa is only dummy tank like f22 craptor & almighty f35 Cheers

rkap wrote:

TEG wrote:

But how long do the -117 engines last? TBO? How many overhaul cycles can can be performed before the engine is considered 'life expired' (AKA - Junk)

The 117S - NPO Saturn says - Assigned life 4,000 hours and an MTBO of 1,000 hours.
Don't go on about the Mig25 - a quick interim upgrade of a disposable Cruise Missile engine. The Russians knew its limitations and never denied them. That comparison is a bit like those who rave on about F15's taking out downgraded and outnumbered Mig23's and Mig25's. They should! easily. A good comparison would be how they would go against {Russian] Mig31's in equal numbers and with equal support.

I'll answer this whit another post I did on this very subject not over a week ago.

TEG

That_Engine_Guy wrote:

Flight Global wrote:

The current production-standard RD-33MK selected for Indian navy MiG-29K/KUBs develops 20,000lb of thrust and has a 1,000h TBO

http://www.flightglobal.com/articles/20 ... ussia.html

Consider the lowest module TBO on the PW-229 is almost twice that (For the Gearbox Module of the Viper, Eagles get more time than that.) The other 4 major modules currently serving in the PW-229 are rated for 4300 "Total Accumulated Cycle" a.k.a. TAC.

New production PW-229EEP engines are rated to 6K TAC!

PW White Paper wrote:

Incorporation of the F100-PW-229 EEP — successfully demonstrated in 2004 — achieves the objective of increasing the engine depot inspection interval from 4300 to 6000 TAC. This increase is equivalent to extending the depot interval from seven years to ten years. In addition, the EEP provides a 30 percent life cycle cost reduction over the life of an F100-PW-229 engine.

(The PW-229EEP has been infused with a bit of F119/F135 tech by PW Wink

)

The other thing to note is "reported service life is apparently 4,000 hrs"; which means after roughly 4 overhauls, throw the engine away.

The F100/F110s on the other hand have been overhauled for decades. The PW-100s were finally removed from their final active service just a year or so ago. They do live on (for a bit) in the PW-100D - upgraded to 'D' standard for use in the QF-16 Drone program. (A, B, C were taken, D was next but does fit nicely for drone) While the PW-220(E) were removed from Vipers going to AMARC, the PW-100s were retired from service and placed into the retired Viper airframes. Just in the last month I touched a motor that started PW0E68xxxx. She had been a PW-100 upgraded to a PW-220E and is still in active service; overhauled many MANY times (likely more than 4x) since her introduction decades ago.

Meanwhile our Russian jet engine brothers are bragging about 1K hour TBOs and 4K Hour service lives? They may be cheaper up front, and cheaper to repair for the first decade, but how many replacement engines do you have to buy to keep your fleet flying after 30-40 years like the USAF Eagles?

Poke

TEG

Keep 'em flyin' Thumb

TEG

Forum: Technology

Sukhoi T-50 PAK-FA