Why Tejas and Su-30MKI Have Different Color of Afterburner Flame?

The afterburner flame is an integral part of aircraft engine technology, especially in military fighter jets. It boosts the aircraft’s performance during takeoff, supersonic flight, and combat engagements. The afterburner flame is created when additional fuel ignites secondary combustion in the afterburner section of the engine, increasing thrust.

The intensity and color of the afterburner flame vary depending on factors like fuel type, engine design, and temperature. This information provides valuable insights into the engine’s performance and operating conditions, making it an essential aspect of aircraft engine technology.

Afterburner Flame In Tejas and Sukhoi Su 30MKI 

Why Tejas and Su-30MKI Have Different Color of Afterburner Flame?
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. 

Why Tejas and Su-30MKI Have Different Color of Afterburner Flame?
Su-30MKI

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 a 3000-hour full life span.  

Why Tejas and Su-30MKI Have Different Color of Afterburner Flame?
Tejas

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.

Performance 

  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 Russian and American aircraft engines need different fuels to refuel them. The color 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 color flame with the use of different fuels. For example, copper burns with a green flame, and sodium produces yellow light while burning. The type of fuel is specially selected in keeping mind for the aircraft. However, 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 color of the flames of fighter aircraft generally depends on temperature:

● 600- dark red. 

● 1300- yellow. 

● 2500- blue. 

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