The document compares the HAL Tejas and JF-17 Thunder fighter aircraft. The Tejas is an Indian light combat aircraft developed by HAL with a delta wing design, while the JF-17 Thunder is a Chinese-Pakistani developed light weight multirole fighter with swept wings. Key specifications like top speed, thrust, weight, and thrust-to-weight ratio are provided for each. The document also provides details on turbofan engine design, delta wing advantages, and swept wing characteristics for both aircraft.

2. Engine Comparison
HAL Tejas JF 17 Thunder
General Electric F404 Klimov RD-93

3. Turbofan
• Some of the incoming air passes
through the fan and continues on
into the core compressor and then
the burner
• The hot exhaust passes through
the core and fan turbines and then
out the nozzle, as in a basic
turbojet. The rest of the incoming
air passes through the fan and
bypasses,
Design
• turbofan engine is the most modern
variation of the basic gas turbine
engine.
• the core engine is surrounded by a
fan in the front and an additional
turbine at the rear and are
connected to an additional shaft.
• The fan shaft passes through the
core shaft
• This type of arrangement is called
a two spool engine (one "spool" for
the fan, one "spool" for the core.)
Working

4. Core Compressors
and Turbine
Core Compressors
and Turbine with
fan and fan turbine

5. Afterburner
•Most modern fighter aircraft
employ an afterburner on either a
low bypass turbofan or a turbojet.
•The afterburner is used to put
back some energy by injecting fuel
directly into the hot exhaust.
• When the afterburner is turned
on, additional fuel is injected
through the hoops and into the hot
exhaust stream of the turbojet.

7. Engine Comparison
Items JF 17 Thunder HAL Tejas
Top Speed Mach 1.6 Mach 1.6
Total Dry Thrust 11510 lbf 12100 lbf
Total thrust with After
Burner
19000 lbf 20200 lbf
Maximum Loaded
Weight
12500 Kg 13200 Kg
Thrust to Weight Ratio 1.09 1.07

8. Wing Design Comparison
HAL Tejas JF 17 Thunder
Delta Wings Swept Wings

9. Delta wings:- Eg Hal Tejas, MiG-21, Avro Vulcan etc
• The delta wing is a wing shaped in the form of a triangle. It is named
for its similarity in shape to the Greek uppercase letter delta(Δ)
• This wing was pioneered by Alexander Lippisch in Germany after
WW1
• It is great for low-speed handling and high-speed manoeuvrability and
allow a greater centre of gravity range.
• SAAB of Sweden developed a Close-coupled canard delta
configuration which has become common in supersonic fighter
aircraft . It modifies the airflow over the wing, most notably when
flying at high angles of attack.

10. Delta Wings Advantage:
•Can fly at high angles of attack- which that's why fighter
jets use a delta wing to fly at very high angles of attack.
•Provides good amount of drag for landing - On landing
you need drag and that's the purpose of flaps is to increase
drag and lift and you can make the flaps a little bit smaller.
•A delta wing is naturally stable in pitch, therefore it does
not require a separate tail surface

11. How swept angle is measured?
The characteristic "sweep angle" is normally measured by drawing
a line from root to tip, 25% of the way back from the leading edge,
and comparing that to the perpendicular to the longitudinal axis of
the aircraft

12. Swept wings:MiG-15, F-86 Sabre, A-10 etc
• A swept wing is a wing which angles either backward or occasionally
forward from its root rather than in a straight sideways direction.
• Earliest swept wing designs was used by Jose Weiss to construct a swept-
wing tail-less glider in 1908 in England.
• Swept back wings is used in airplane to solve the problem of turbulence
and drag at high speed.
• Swept forward wing is used to make the flight of slow moving aircraft
more stable
• Straight wings are also adopted for small planes with short takeoff and
landing (STOL), low speed, and for less fuel consumption
• The fighter jet F-111 has variable sweep wings. They can move forward
and backward at 16 degree and 70 degree respectively. Here the
combination was achieved to allow the fighter to fly more stably from
low speed to supersonic speed.

13. Swept forward wing
There have only been a few aircraft built with forward-swept wings. Most
notably was the X-29
Advantages:
•The wing spar carry-through can be placed aft of
the cabin, so cabin height can be increased. This is
important for business-jet sized aircraft.
•The boundary layer at the tips is not affected by
the inner wing. Controllability can be maintained
up to stall.
•Aeroelastic effects will increase control
commands. This makes for a very responsive
airframe

14. Disadvantage
• Stall will happen inboard first, which will result in a
pitch-up. If the tail cannot compensate, the stall is
unrecoverable.
• The aeroelastic effects will encourage flutter. If flutter
speed is found to be too low, the wing needs to be made
stiffer, resulting in a weight increase.

15. Swept back wing
Advantage:
•Wing sweep also helps in longitudinal stability
by stretching out the wing lengthwise. This is
important for flying wings which lack a separate
tail surface
• A swept back wing is more suited for aircraft
operating at higher speeds, while the
conventional wing that extends closer to a right
angle from the fuselage is more suited for
providing better lift at lower speeds.
Disadvantage: They stall tip-first, which means
you can lose use of your ailerons at low speed
It is common and is found on every airplanes and fighter planes

16. Tejas -Indian Light Combat
Aircraft (LCA), is the smallest and
lightest Multi-Role Supersonic
Fighter Aircraft of its class. This
single engine, Compound-Delta-
Wing, Tailless Aircraft is designed
and developed by ADA with HAL
as the principal partner along with
DRDO, CSIR, BEL, DGAQA and
IAF to meet diverse needs of the
Indian Air Force (IAF).
HAL TEJAS

21. JF-17 THUNDER
• JF-17 Thunder is a light weight aircraft developed jointly
by Chengdu industries (China) and Pakistan Aeronautical
Complex.
• Concept was developed in 2003 in China.
As Pakistan was looking for an affordable multirole aircraft,
China offered Pakistan to invest in this project.
• Its designation “JF-17” is “Joint Fighter-17” in Pakistan
and “FC-1” as “Fighter China-1 Fierce Dragon” in China.
• It is light weight multirole, single- engine combat aircraft .
It is a 4th generation fighter aircraft.

22. Design & Features
• The software of JF-17 thunder is hinge on Civilian c++ which
controls the avionics of aircraft.
• Motorolla 88000 microprocessor powers the avionics of aircraft.
• JF-17 is powered by a turbofan engine imported directly from
Russia.
• Aircraft glass cockpit has a Electronic Flight Instrument system
(EFIS) and a wide holographic display which has the field view of
25 degrees.

23. JF-17 Thunder Engine Type
• JF-17 thunder is powered by turbofan engine.
• Engine produces the thrust of 19000lbs which takes the aircraft to
the speed of 1,218miles per hour.
• Pakistan import turbofan engine straightly from Russia for JF-17
Thunder.
• Turbofan engine are quitter due to their greater mass flow and
lower total exhaust speed. They are more efficient for range of
subsonic speed and for cooler exhaust system.

24. WEAPONS

25. The final comparison
• Role: Deep penetration strike
aircraft.
• 4th generation aircraft.
• Maximum Range: 3000 KM
• Nuclear Capability: Yes, can carry
nuclear warheads.
• Can fly in all weather conditions.
•Role: Air defense interceptor.
3rd generation aircraft
•Maximum Range: 3482 KM
•Nuclear Capability: No, not able to
carry nuclear warheads.
•Not tested in all weather conditions.
Tejas JF-17

28. Thank You