Su-30MKI and LCA Tejas

These fighter aircraft ( Tejas and Sukhoi Su 30MKI) use different types of engines- Sukhoi Su 30MKI uses a Russian-made engine Lyulka-Saturn AL-31FP. In comparison, Tejas uses an American-origin engine General Electric F404-GE-IN20. 

Two Lyulka-Saturn AL-31FP turbofans are used to give power to each Sukhoi SU 30MKI aircraft. Each of these fans is rated at 12500 kg(27000lbf), which has full afterburning thrust capable of gaining up to Mach 2 speed during horizontal flight and has a rate of climb of 230 m/s. The average time between two overhauls is 1000 hours, and it has 3000 hours full life span.  

In comparison, Tejas gets The General Electric F404 engine which belongs to a family of afterburning turbofan engines with a weight between the range from 10500 to 19000 lb and having 47-85KN static thrust produced by GE Aviation in partnership with Volvo Aero, which makes the RM12 variant engine. The General Electric F404 engine was developed into the larger F414 turbofans with the experimental GE36 civil propfan.


  1. An afterburner has a maximum military thrust of 11000 lb ( 48.9 KN) and reaches 17000 lb ( 78.7 KN).
  2. Its overall pressure ratio is 26:1
  3. The bypass ratio is 0.34:1 
  4. Specific fuel consumption during Military thrust is 0.81 lb/lbf/h (83kg/KN/h) and during 
  5. Full Afterburner is 1.74 lb/lbf/h (177 kg/KN/h) 
  6. The thrust to weight ratio is 4.8 (dry), 7.8 (afterburning)  

Which Gamma is better? 

Both the Russian as well as American aircraft engines need different fuels to refuel them. The colour of these engine flames differs due to their specific temperature and the refraction of light. Hence the main reason behind the colour is temperature differences and the type of fuel. 

During combustion, both of these engines produce a different colour flame with the use of different fuels. For example, copper burns with a green flame, and sodium produce yellow light while burning. The type of fuel is specially selected in keeping mind for the aircraft. But in modern fighter aircraft, it has the property of interchangeability. For example, Sukhoi Su 30MKI can be seasoned with a mixture of F-35. therefore the colour of the flames of fighter aircraft generally depends on temperature:

● 600- dark red. 

● 1300- yellow. 

● 2500- blue. 

Hence the aircraft thrust depends on a specific temperature. The Bigger thrust means the stronger, which changes the colour of the temperature. So the conclusion is the colour comes at the temperature of 600 degrees.