MastanKhan
VIP Member
Hi,Even the F-7/ Mig-21s had more, they famously had 45 mins of endurance without external tanks. With a fuel fraction of 27.5, significantly higher than that of the F-7 (0.24 from memory), The J-10 should be able to give north of 1 hour patrol time at or near base without external tanks.
Some back ground: We know there are three variables that affect range and endurance:
1. Aero foil configuration or Lift-to-Drag ratio: The F-7 and J-10 are both deltas but the J-10 has canards which improves flow characteristics. Also, the J-10 was conceived in different light vs the Mig-21s interceptor design parameters, hence other characteristics like aspect ration, wing thickness etc would favour a multi-role cruiser over an interceptor dasher design.
2. Propulsion efficiency: Swap a turbo-fan for a tubo-jet and you get more range and endurance. The J-10 does that.
3. Fuel fraction: see breguet's range equation. Not as good as other modern deltas (Typhoon 0.31, Rafale 0.32 - again from memory), but better than F-7 and Jf-17.
The Jf-17 improves on 1 and 2 vs the F-7 but not really on 3, hence its short legs compared to J-10 and one of the reasons for the J-10 making its way into PAF.
A good summary: https://people.clarkson.edu/~pmarzocc/AE429/AE-429-11.pdf
I believe mig21's total time in air was 30-45 minutes or so with external fuel tanks.
Listen to Sattar Alvi's interview---. After 30-45 minutes in air---the israelis would send their aircraft to take them down because they were almost out of fuel ready to land---.








