Mughal-Prince
SENIOR MEMBER
- Joined
- Mar 16, 2010
- Messages
- 2,523
- Reaction score
- 1
- Country
- Location
RD-93 Engine: Strength or Weakness?
- Thread starter FC-20
- Start date
VCheng
ELITE MEMBER
- Joined
- Sep 29, 2010
- Messages
- 48,413
- Reaction score
- 57
- Country
- Location
A little Photoshop is all it takes, like with the photograph above.
Kompromat
ADMINISTRATOR
- Joined
- May 3, 2009
- Messages
- 40,366
- Reaction score
- 416
- Country
- Location
No, these are original RD-93 and boy they were smoky. The ones we have are D variant. The next one is MA variant with 10 tonnes of added thrust. With 1.09 TWR, JFT's flight performance would be similar to the hornets.
slapshot
FULL MEMBER
- Joined
- Dec 8, 2011
- Messages
- 1,745
- Reaction score
- 1
- Country
- Location
Updated.No, these are original RD-93 and boy they were smoky. The ones we have are D variant. The next one is MA variant with 10 tonnes of added thrust. With 1.09 TWR, JFT's flight performance would be similar to the hornets.
1.09 TWR along with full payload ?
VCheng
ELITE MEMBER
- Joined
- Sep 29, 2010
- Messages
- 48,413
- Reaction score
- 57
- Country
- Location
No, these are original RD-93 and boy they were smoky. The ones we have are D variant. The next one is MA variant with 10 tonnes of added thrust. With 1.09 TWR, JFT's flight performance would be similar to the hornets.
Yes, the older engines are smokier, but not that smoky. That photo has black shades enhanced to mislead.
MastanKhan
PDF VETERAN
- Joined
- Dec 26, 2005
- Messages
- 21,269
- Reaction score
- 166
- Country
- Location
Hi,
I am pretty sure it the fuel that is causing this smoke-----. I wrote in a prior post that the russian aircraft of the 70's and 80's were smokeless and the americans had a lots of smoke---and when the americans got a mig from libya defect in israel---they found the russian fuel in the tank and on analysis they found out the chemical structure of the fuel was customozed at molecular level by using a certain process-----.
Well---the person who was handed over the bottle containing the fuel and the tests that were performed---I know him---as a matter of fact I was with him about 1 / 2 an hour ago---.
This fuel seems like it has a lots of sulphur in it------. For those who cannot comprehend----let me give you another personal example-----.
The new audi V6 diesel on the Q 7-----is smokeless----I staretd up the SUV and sat down behind the exhaust and smelled the exhaust coming out----it did not smell of diesel fumes----it was clean----cleaner than gasoline---shocking.
The vehcile was running on the showroom floor---closed area and not a whiff of diesel exhaust----the reason being---the newer fuels have minimal sulphur content and and the vehicle has catalysts and converters to remove harmful visible pollutants.
Hi,
The motto of Honda and Toyota ---- QUALITY IS CHEAPER IN THE LONG RUN though it may cost more in the begining.
I am pretty sure it the fuel that is causing this smoke-----. I wrote in a prior post that the russian aircraft of the 70's and 80's were smokeless and the americans had a lots of smoke---and when the americans got a mig from libya defect in israel---they found the russian fuel in the tank and on analysis they found out the chemical structure of the fuel was customozed at molecular level by using a certain process-----.
Well---the person who was handed over the bottle containing the fuel and the tests that were performed---I know him---as a matter of fact I was with him about 1 / 2 an hour ago---.
This fuel seems like it has a lots of sulphur in it------. For those who cannot comprehend----let me give you another personal example-----.
The new audi V6 diesel on the Q 7-----is smokeless----I staretd up the SUV and sat down behind the exhaust and smelled the exhaust coming out----it did not smell of diesel fumes----it was clean----cleaner than gasoline---shocking.
The vehcile was running on the showroom floor---closed area and not a whiff of diesel exhaust----the reason being---the newer fuels have minimal sulphur content and and the vehicle has catalysts and converters to remove harmful visible pollutants.
Hi,
The motto of Honda and Toyota ---- QUALITY IS CHEAPER IN THE LONG RUN though it may cost more in the begining.
Dear sir, how you know that it is photo-shopped. Any knowledge sharing, please.
VCheng
ELITE MEMBER
- Joined
- Sep 29, 2010
- Messages
- 48,413
- Reaction score
- 57
- Country
- Location
You know one of the most irritating aspects is zero learning capability of certain group of posters. There are some aspects related to smoke. The less sulphur helps. So you do not make it from african, latin american or Indonesian oil. People who know what blending is should not have problems understanding it. The USA never used second grade fuel. It gets its fuel from KSA which is probably the cleanest. For the rest engines are better and better these days. Combustion is computer controlled and even if certain parts survive it will get toasted in the "catalysator"... Last part with extremely high temperature...
For the big part our specialist of cars pretty much hits the nail. With a stupid fight in the beginning I am going to like this poster more and more. I hope to visit my friends in SF/LA so we maybe have some chai together.
People returning with JF17 has smoke... Every engine has under certain settings or changes. I have seen all the engines from rd33 till rd93. Opened. Running. I have been a few feet away during startup. Trust me. It is perfect. Posters posting that it is photoshopped blabla.. Please stop hurting yourself. It is not only frustrating to read your posts but it must be pretty much unrealistic to write that shi t.
Anyway. those low level mig29 are polish. Former eastern germany. They use perfect fuel that goes same way in their block52. But it is a very basic and rugged engine. They do not have digital controlled anything. So when you lower your speed and pull forward the fuel handle.... This is what you get... Lots of fuel, low oxygen and bad burning....
For the big part our specialist of cars pretty much hits the nail. With a stupid fight in the beginning I am going to like this poster more and more. I hope to visit my friends in SF/LA so we maybe have some chai together.
People returning with JF17 has smoke... Every engine has under certain settings or changes. I have seen all the engines from rd33 till rd93. Opened. Running. I have been a few feet away during startup. Trust me. It is perfect. Posters posting that it is photoshopped blabla.. Please stop hurting yourself. It is not only frustrating to read your posts but it must be pretty much unrealistic to write that shi t.
Anyway. those low level mig29 are polish. Former eastern germany. They use perfect fuel that goes same way in their block52. But it is a very basic and rugged engine. They do not have digital controlled anything. So when you lower your speed and pull forward the fuel handle.... This is what you get... Lots of fuel, low oxygen and bad burning....
Last edited:
VCheng
ELITE MEMBER
- Joined
- Sep 29, 2010
- Messages
- 48,413
- Reaction score
- 57
- Country
- Location
Engine control computers can minimize smoke during throttle transitions too.
Oh, and some will understand what others will call bla bla bla.
========================================
Edit: Quite funny to see additional bla bla bla added to a post above after my comment about engine control computers above.
Oh, and some will understand what others will call bla bla bla.
========================================
Edit: Quite funny to see additional bla bla bla added to a post above after my comment about engine control computers above.
Last edited:
niaz
PDF THINK TANK: CONSULTANT
- Joined
- Jun 18, 2006
- Messages
- 5,164
- Reaction score
- 211
- Country
- Location
Earlier jet engines ran on gasoline based fuel known as JP-4. Modern jet engines run on kerosene fuel which has very strict specification in terms of water, freezing point, electrical conductivity etc.
International specification of Jet fuel is currently known as Def Stan 91-91 standard. There is always anti-static additive added to improve lubricity of the fuel. US Military jet fuels JP-5 & JP-8, primarily for use on aircraft carriers, are defined by Mil-DFL-5624 & MIL-DFL-83133.
No air force would risk a $50-million plane & endanger life of the pilot by putting bad fuel. For passenger jets, guidelines are ever stricter and a sealed sample of the fuel pumped into the aircraft is kept by the suppliers until the air craft lands at the next airport.
My point here is that in case of aircraft jet engines, it is not the quality of the fuel that causes the smoke whether it is Russian, Chinese, Indian or the US origin.
Smoke has only one cause; that is incomplete combustion. (We are discussing black smoke here not the blue or white smoke that sometimes comes out of automobile exhaust representing worn out piston rings or leaking engine gaskets).
On very simple terms, a jet engine has 4 basic sections. The intake, the compressor, the combustion and the exhaust section. Exhaust gasses exit thru a turbine which runs the compressor of the air intake. Smoke will be produced when there is not complete combustion. For example in the after burner when additional fuel is pumped into hot exhaust gasses to get more thrust; there will always be some smoke and one can even see the flame coming of the exhaust.
Getting maximum thrust out of small jet engines has always been a huge problem for the aircraft engine designers. Therefore more fuel is injected into the combustion chamber than can be burned completely, given the amount of oxygen present and the residence time of the fuel molecules resulting in the unburnt carbon coming out as smoke. Remember smoke is essentially mixture of carbon particles and the air.
RD-93 is a reliable turbofan engine and I am sure that given time; Klimov engineers will manage to eliminate the smoke problem.
International specification of Jet fuel is currently known as Def Stan 91-91 standard. There is always anti-static additive added to improve lubricity of the fuel. US Military jet fuels JP-5 & JP-8, primarily for use on aircraft carriers, are defined by Mil-DFL-5624 & MIL-DFL-83133.
No air force would risk a $50-million plane & endanger life of the pilot by putting bad fuel. For passenger jets, guidelines are ever stricter and a sealed sample of the fuel pumped into the aircraft is kept by the suppliers until the air craft lands at the next airport.
My point here is that in case of aircraft jet engines, it is not the quality of the fuel that causes the smoke whether it is Russian, Chinese, Indian or the US origin.
Smoke has only one cause; that is incomplete combustion. (We are discussing black smoke here not the blue or white smoke that sometimes comes out of automobile exhaust representing worn out piston rings or leaking engine gaskets).
On very simple terms, a jet engine has 4 basic sections. The intake, the compressor, the combustion and the exhaust section. Exhaust gasses exit thru a turbine which runs the compressor of the air intake. Smoke will be produced when there is not complete combustion. For example in the after burner when additional fuel is pumped into hot exhaust gasses to get more thrust; there will always be some smoke and one can even see the flame coming of the exhaust.
Getting maximum thrust out of small jet engines has always been a huge problem for the aircraft engine designers. Therefore more fuel is injected into the combustion chamber than can be burned completely, given the amount of oxygen present and the residence time of the fuel molecules resulting in the unburnt carbon coming out as smoke. Remember smoke is essentially mixture of carbon particles and the air.
RD-93 is a reliable turbofan engine and I am sure that given time; Klimov engineers will manage to eliminate the smoke problem.
MastanKhan
PDF VETERAN
- Joined
- Dec 26, 2005
- Messages
- 21,269
- Reaction score
- 166
- Country
- Location
@niaz,
Could you please be kind enough to explain then why the russian aircraft were smokeless and and the americans smoked during the 60's and 70's----.
Because I am getting a totally different picture from the chemical engineer who analyzed the russian fuel obtained from the defecting libyan aircraft into israel during the 70's---.
The russians already had smokeless engines in the 60's 70's ---- the issue is that what is it now that they are giving out smoke---and the american engines that produced a lots of smoke in the past are smoke less now!
Could you please be kind enough to explain then why the russian aircraft were smokeless and and the americans smoked during the 60's and 70's----.
Because I am getting a totally different picture from the chemical engineer who analyzed the russian fuel obtained from the defecting libyan aircraft into israel during the 70's---.
The russians already had smokeless engines in the 60's 70's ---- the issue is that what is it now that they are giving out smoke---and the american engines that produced a lots of smoke in the past are smoke less now!
Last edited:
HAIDER
ELITE MEMBER
- Joined
- May 21, 2006
- Messages
- 33,771
- Reaction score
- 14
- Country
- Location
Any jet engine can produce smoke if there is not enough oxygen to completely burn the fuel. The smoke itself is carbon particles also known as soot. It's not limited to just Russian fighters. American fighters, European fighters, even passenger jets can have smoky exhausts.
Some combustion equations:
Complete combustion (no smoke): 2(C8H18)+25(O2)->16(CO2)+18(H2O)
Incomplete combustion (produces carbon monoxide): 2(C8H18)+17(O2)->16(CO)+18(H2O)
Incomplete combustion (produces soot): 2(C8H18)+9(O2)->16(C)+18(H2O)
May be Russian engine technology lags behind the western nations. Also, when doing heavy maneuvers most jets produce lots of smoke because the G forces and attitude changes have a negative effect on the most efficient gas flow and combustion in the engine.
Some combustion equations:
Complete combustion (no smoke): 2(C8H18)+25(O2)->16(CO2)+18(H2O)
Incomplete combustion (produces carbon monoxide): 2(C8H18)+17(O2)->16(CO)+18(H2O)
Incomplete combustion (produces soot): 2(C8H18)+9(O2)->16(C)+18(H2O)
May be Russian engine technology lags behind the western nations. Also, when doing heavy maneuvers most jets produce lots of smoke because the G forces and attitude changes have a negative effect on the most efficient gas flow and combustion in the engine.
Similar threads
