RD-93 Engine: Strength or Weakness?

[FC-20]

Although the engine has come under a lot of scrutiny from Pakistani quarters, the main aspect has been over performance issues. The engine is considered to be smoky & under-powered, while reliability has also been expressed as a point of concern. With a presumed low TBO (Time Between Overhauls) the type has been stated as a weak-point.The RD-93 is actually superior to all PAF service engines except the F100 series of the F-16 (however, it does have better response cycle to turbulence & dust), & is more fuel efficient, quieter, & reliable (as well having a longer lifespan) than the Atar 9C (Mirage III/5), WP-7 (F-7P) & WP-13 (F-7PG) in PAF service, all being turbojets & not comparable. The RD-93 itself actually would save the PAF on fuel & logistics, being economical to acquire & operate. It also offers much more thrust & efficiency than even the F100.
Its main weaknesses remain the smoky nature of the engine, & low-lifespan compared to the F100. Other weaknesses can be found in its design. Though not low on thrust (it is actually lighter than the Atar 9C & saved 400kg on South African Mirage F.1s during fits) the type is optimised for the twin-engined MiG-29. One possible solution is to produce the RD-33MK/MR (Naval) standard, with 19,400lb reheat coupled with weight savings on the FC-1.What appears to be unmentioned is that the RD-93 is much more powerful than the European RD199 (Tornado F3) & much more durable than the M53 (Mirage 2000) & is much better performing than both at high altitudes or turbulence. It also beats the F100 in such conditions. It's also designed for rapid repair & field maintenance & contrary to popular belief is not a thirsty engine. Though less durable than the F404 or PW1120 series (its US equivalents) it is actually more responsive to bird-strikes, & FOD.The next phase of RD-93 development would focus on enlarging the blades of the fans (much the same way as the EJ200 or M88 & some re-designs around the engine. This should make it a revolution (as opposed to just an evolution) of the basic design, & may well go beyond 22k at reheat. Coupled with reduced FC-1 weight, this would equalise the F-16C/D with uprated PW F100-229E engines, (note: the F-16C/D is heavier & less agile) & the possibility of super-cruise.My hope is that the Chinese can develop a suitable replacement but in all honesty as this rate they aren't doing too well. The WS-9 (Spey 202 copy) has the power but consumes more fuel & is too big & heavy, where the WP-14 is too under-powered & thirsty (being a turbojet) so improvements to the RD-93 is the only way to go.

First FC-1 is:

14,134 lb (Empty)
20,062 lb (Fueled + Two Wing-tip missiles)
28,000 lb (Max. Take Off Weight)

5,130 lb of fuel



Comparison of engines: (Note: fuel consumption of the Eurocanards haven't been given yet but are lower than both the RD-93 or F404).

RD-93:
- Dry weight: 2,325 lb
- Military Thrust 11,230 lbf
- Reheat Thrust 18,285 lbf

Specific fuel consumption:

0.77 lb/(lbf·h)) military thrust
2.05 lb/(lbf·h)) with reheat


F404:
- Dry weight: 2,282 lb
- Military Thrust 11,000 lbf
- Reheat Thrust 17,700 lbf

Specific fuel consumption:

0.81 lb/(lbf·h) military thrust
1.74 lb/(lbf·h) with reheat


M88:

- Dry weight: 1,978 lb
- Military Thrust 11,250 lbf
- Reheat Thrust 17,000 lbf

Specific fuel consumption:

??? lb/(lbf·h) military thrust
??? lb/(lbf·h) with reheat




EJ200:

- Dry weight: 2,180 lbs
- Military Thrust 13,500 lbf
- Reheat Thrust 20,250 lbf

Specific fuel consumption:

??? lb/(lbf·h) military thrust
??? lb/(lbf·h) with reheat

M53P2:

- Dry weight: 3,340 lbs
- Military Thrust 14,300 lbf
- Reheat Thrust 21,384 lbf

Specific fuel consumption:

0.92 lb/(lbf·h) military thrust
2.15 lb/(lbf·h) with reheat


Perhaps most surprisingly to some, the RD-93 is actually more efficient than the F404 on military thrust but on military thrust despite being thirstier, it's still more efficient from a combustion standpoint. Therefore the RD-93 on merit, but the EJ200 is the best power-plant & the M88 is competitive but just too under-powered.

 

[MastanKhan]

Hi,

Thanks for talking about the rd 93----smoke is not a big issue at all---the phantom was a smokers dream---it did no harm to the reputation or the ability of that plane. The plane flew right to the end with smoke coming out through its twin pipes---.

Fighter jet engines are the most difficult engineering ventures that you can ever come across---once the upgraded versions of this engine get close the the thrust of comparable american engine---it will give a big boost to the plane.

Now coming down to the life span---paf has always done a great job at squeazing the most life out of any jet engine in its service---rd 93 will be its biggest challenge in the next 5 years.

 

[Rank]

koi nahi 2 stroke motorcycle sahi cylincer utaar kar uraleengay dun worry lol

 

[PAFAce]

Hi,

Thanks for talking about the rd 93----smoke is not a big issue at all---the phantom was a smokers dream---it did no harm to the reputation or the ability of that plane. The plane flew right to the end with smoke coming out through its twin pipes---.

Thats true. But, something has to be said about the era as well. The heat-seaking missiles now are very sophisticated, and so is electro-optical surveillance equipment. Visual signatures such as engine smoke are more than just a nuisance.

Of course, one can make the argument that in the age of BVR, IR and visual signatures lose much of their importance. However, combat aircraft like the JF-17 are still designed with close combat in mind, and so letting the engine smoke is against to the design objectives. I mean, incorporating DSI and then letting the engine smoke, doesn't make sense.

Fighter jet engines are the most difficult engineering ventures that you can ever come across---once the upgraded versions of this engine get close the the thrust of comparable american engine---it will give a big boost to the plane.

I'm glad you pointed this out. Many here don't realise how complex aircraft engine engineering is. There are many quality airframe engineering companies around the world, but there are only a handful of quality engine developers. Pratt & Whitney, General Electric, Rolls Royce and maybe one or two others. That's about it. Engine design is very complex indeed.

Now coming down to the life span---paf has always done a great job at squeazing the most life out of any jet engine in its service---rd 93 will be its biggest challenge in the next 5 years.

The Russians are also very good at squeezing every ounce of performance out of a design. This fact even became a bit of a joke in the West during the Cold War. For example, look at how many variants there are of the Su-27, and before that, the Mig-25 etc. Engines are probably the same. If Russia continues to develop the RD-33, i.e., the RD-93 indirectly, maybe we might not even require a new Chinese engine down the road.

 

[BATMAN]

I really appreciate the effort here by FC-20.
I have always been wondering, when RD-33 is the front line engine of Russia than it can't be as bad as it turned out in indian service.
RD-33 (MK!) is also used in mig-35 which is still not in serial production.
Mig-35 will be main stay of Russian airforce in future hence I expect it to develop further in quality and performance.
Only if PAF may try to get RD-93 based on new RD-33, that would be wonderful.
With WS-13 we have even higher hopes in terms of TBO and sanction proff.

IR signature from the exhaust can not be eliminated and have no relation with color of smoke.
As I learn from comments of PAF vetrans that smoke is not always there and is in some specific throtle positions or while performing specific manuvers and it can also be seen from many of the pictures where smoke is missing.

 

[sancho]

I really appreciate the effort here by FC-20.
I have always been wondering, when RD-33 is the front line engine of Russia than it can't be as bad as it turned out in indian service.
RD-33 (MK!) is also used in mig-35 which is still not in serial production.
Mig-35 will be main stay of Russian airforce in future hence I expect it to develop further in quality and performance.
Only if PAF may try to get RD-93 based on new RD-33, that would be wonderful.
With WS-13 we have even higher hopes in terms of TBO and sanction proff.

IR signature from the exhaust can not be eliminated and have no relation with color of smoke.
As I learn from comments of PAF vetrans that smoke is not always there and is in some specific throtle positions or while performing specific manuvers and it can also be seen from many of the pictures where smoke is missing.

Russia won't have any Mig 35, they only might upg older Mig 29 with new radar and that engine, but the only new Migs to be ordered are Mig 29K for their carriers.
There was a news report in the JF 17 thread some month ago that Russia offers an AESA radar and an upgraded RD 93 engine (90kN), which could be the Zhuk AE and RD 33 MK. Not sure if it those will be available for PAF too, but it would be a good upgrade for JF 17 block 2.

 

[FC-20]

thanks Batman...
The main problem with over-smoking is that it makes an aircraft easier to acquire visually right, i read some where that the trial can help increase RCS at times....
Radar waves would magnify not by much but significantly
Then again turning on reheat (afterburners) would raise RCS by 50% & drop-tanks by 50-100%, is that right?

 

[Arsalan]

well of course, the smoke trail make it more visible, both within visin and on radar.
also the afterburner, or heat in any form increases radar signature. it is not right to term this phenomena as increase in RCS as it is pretty much a physical feature but yes it increases the radar signature. it is for this reason that the world is moving to cooled engines and sheilding the heat generated for next generation engines!!

regards!

 

[BATMAN]

Less heat means less IR signature and not greater RCS.
I assume only infrared sensors can see the heat signature and not the classic electromagenatic radars.
I'm not reading from web but in my common sense, IR sensors has to be directional and it should be able to read all temperatures high or low!
Smoke can only aid visual sighting!
But how, the color of smoke can aid electromagnetic radar?

maybe we might not even require a new Chinese engine down the road.

Best case senario for Pakistan is equally good Chinese engine self production.
Why do we forget sanctions when we talk about JF-17's engine! where as when it comes to F-16 we immediately consider sanctions.
Sanctions are puerly lobby work in US, and there active all the time!
I think, I will start a thread on this issue.

 

[PAFAce]

Best case senario for Pakistan is equally good Chinese engine self production.

You're right about that. Or, in fact, a Chinese engine with some basic ToT so we can upgrade, refurbish and overhaul out own JF-17 engines in the future. In other words, if we never have to send the engine outside of Pakistan once it has entered the country (from China or Russia), then, in my opinion, we will achieve the ultimate goal from this engineering venture. Next step would be to try and manufacture some at home, but let's not get ahead of ourselves.

 

[Kamakazi 69]

Didn't the MiG design board change the RD-33 on later MiG-29s due to reliability issues? Hopefully we have solved those issues.

 

[sob]

Is this the same engine as RD 33 fitted on IAF Mig29s, or have the Russians done some improvement over the engines.

Earlier HAL had a torrid time maintaining these engines at their facility at Koraput.

 

[sancho]

Is this the same engine as RD 33 fitted on IAF Mig29s, or have the Russians done some improvement over the engines.

Earlier HAL had a torrid time maintaining these engines at their facility at Koraput.

It is the same family and should be the same SMR 95 engine, just renamed for use in FC1/JF 17.

Klimov :: Production :: Aircraft Program :: RD-33 family

 

[DaRk WaVe]

so if they are same engine and IAF is having probs maintaining it so wat about its maintenance by PAF?? any one..

 

[PAFAce]

Is this the same engine as RD 33 fitted on IAF Mig29s, or have the Russians done some improvement over the engines.

so if they are same engine and IAF is having probs maintaining it so wat about its maintenance by PAF?? any one..

It's a redesigned RD-33 engine fitted into MiG-29s. Or rather, upgraded to meet new requirements would be a better way to describe it. Either way, it takes time for technology of this complexity to mature, and the RD-33 has been around since the mid '80s. Most of its original issues should have been resolved by now. However, there is no guarantee newer ones won't appear with the RD-93. Further fine tuning of engine requirements by the PAF will certainly follow once we have experience with these engines, and so later blocks of the JF-17 will benefit from that experience. But, until then, it's difficult to speculate what problems may or may not appear.