2. 2
DISCUSSION
1. Propulsion System
2. Power System
3. Maximum Thrust andThrust to Weight Ratio
4. EngineType
5. In-Air Fueling
6. FuelType and Combustion
7. Fuel Capacity
3. 3
Pratt & Whitney's F135 propulsion system is the engine of choice for the F-35 Lightning II.
Primary propulsion for the F-35 is supplied by the Pratt &Whitney F135 turbofan series.The F135 is an
afterburning turbofan system delivering 25,000lbf on dry thrust with up to 42,000lbf on full
afterburner.
6. 6
POWER SYSTEM
The F-35 has 3 electrical systems,
- 28VDC system being used to
power avionics.
- 270VDC system used to power
high-power systems like the
electro-hydrostatic actuators
(which replace conventional
hydraulic systems for control
surfaces) and starter motors,
- 115VAC system used for powering
certain bombs / missiles that
require it.
7. 7
MAXIMUMTHRUST &THRUST-WEIGHT RATIO
The quoted thrust-to-weight ratio indicates the performance of the engine or vehicle and represents
maneuverability of the aircraft.
F-35’s peak power output is 160kW. MaximumThrust of 25,000lbf (DryThrust)
𝑇𝐻𝑅𝑈𝑆𝑇
𝑊𝐸𝐼𝐺𝐻𝑇
=
25,000
60,000
𝑇ℎ𝑟𝑢𝑠𝑡 − 𝑡𝑜 − 𝑊𝑒𝑖𝑔ℎ𝑡 𝑅𝑎𝑡𝑖𝑜 = 𝟎. 𝟒𝟏
MaximumThrust of 43,000 lbf (afterburner)
𝑇𝐻𝑅𝑈𝑆𝑇
𝑊𝐸𝐼𝐺𝐻𝑇
=
43,000
60,000
𝐴𝑓𝑡𝑒𝑟𝑏𝑢𝑟𝑛𝑒𝑟 𝑇ℎ𝑟𝑢𝑠𝑡 − 𝑡𝑜 − 𝑊𝑒𝑖𝑔ℎ𝑡 𝑅𝑎𝑡𝑖𝑜 = 𝟎. 𝟕𝟏
9. 9
STOVL Main Engine Components
The three main components of the F135 that enable both types of airborne flight are
- The Exhaust Nozzle
- The Lift Fan
- The Roll Posts
(Swivel) Exhaust Nozzle
The exhaust nozzle is the most
important part of the F135 engine.
During horizontal flight, 100% of the
thrust generated is due to the exhaust
nozzle. During vertical flight, about
46% of lift generated is used to keep
the jet stabilized.
10. 10
HOW AIR FLOWS WHEN PLANE IS AIRBORNE AND WHEN ITTAKES OFF/
LANDSVERTICALLY
Lift Fan
The lift fan is the second most crucial aspect of
the F135 engine
It forces air downwards 20,000lb of lift
Roll Posts
Placed under both wings, Although the roll posts
only provide about 8% of lift need to keep the
F-35 jet vertical in flight, they are absolutely
necessary as the prevent rolling clockwise or
counterclockwise with the wind.
Nozzles
12. 12
Yes, F-35 Lightning II allows
air-to-air fueling through
AirTankers via two systems.
DOES IT ALLOW
MID-AIR FUELING?
13. 13
i) In the Aerial Boom System, used primarily by the Air Force, the receiving plane flies in close
formation to the tanker. A boom operator in the tanker then flies a rigid boom into a receptacle on the
top of the aircraft.
15. 15
The drogue stabilizes the hose in flight and provides a funnel to aid insertion of the receiver
aircraft probe into the hose.
Most modern versions of the probe are usually designed to be retractable when not in use.
Aerial Boom System provides High rate of Fuel
transfer but one aircraft at a time but
Probe-and-Drogue refuels multiple aircrafts
simultaneously at lower Fuel transfer rate.
17. 17
FUELTYPE & COMBUSTION
JET A-1 OR AVTUR(AviationTurbine Fuel) is a type of fuel used in F-35.
JET A-1 is an aviation fuel formerly known as "kerosene" which is suitable for most jet aircraft.
It has a minimum flashpoint(combusts) of 38°C and a maximum freezing point of -47°C.
JET A-1 is the principal fuel used for jet turbine engines. It is also used in general aviation for
compatible diesel engine planes.
