Ch 2 Systems
Ch 3 Serving and Handling
Ch 4 Operating Limitations
1.1 Aircraft Description
1.1.1 Meet the Super Hornet
The multi-mission aircraft has an internal 20mm gun and can carry AIM-7, AIM-9, and AIM-120
air-to-air missiles; and numerous air-to-ground weapons. The aircraft fuel load may be
increased with the addition up to five external fuel tanks.
The aircraft is powered by two General Electric F414-GE-400 turbofan engines utilizing
Full Authority Digital Engine Control (FADEC). The aircraft features variable camber mid-wing
with leading edge extension (LEX) mounted on the each side of the fuselage. Twin vertical
tails are angled outboard 20 degrees from the vertical.
The aircraft is designed with relaxed static stability to increase maneuverability and to reduce
approach speed and landing speed. The aircraft is controlled by a digital fly-by-wire
Flight Control System through hydraulically actuated flight control surfaces, ailerons,
twin rudders, leading edge flaps, trailing edge flaps, LEX spoilers, and differential stabilizers.
The leading edge of the wing incorporates a " sang, " which increases outboard wing area and
increases roll authority in the approach and leading configuration. A speed brake function is
provided by differential deflection of the primary flight control surfaces.
The pressurized cockpit is enclosed by an electrically operated clamshell canopy. An aircraft
mounted auxiliary power unit (APU) provides self-contained state capability for the engines.
1.1.4 Radar Cross Section (RCS) Reduction
RCS reduction is a significant feature of F-18. While the maintenance community is tasked
with the maintaining the RCS features of the aircraft, it is in the beat interests of the aircrew
community to take an active role to ensure the survivability characteristics of the aircraft are
retained.
RCS reduction is accomplished through numerous airframe design features. The baseline
feature is platform alignment of as many surface edges as feasible. The outer modeling of the
aircraft is treated to make it a smooth, conductive surface in order to reduce radar scattering.
Treatment entails metalizing the navigation lights, canopy, and windshield. Permanent joints and
gaps around infrequently opened panels are filled with a form-in-place (FIP) sealant, which is
blended flush and conductively painted.
2.1 Power System
USS Harry S. Truman (CVN 75). Harry S. Truman is underway conducting carrier qualifications.
2.1.1 Engines
The aircraft is powered by two General Electric F414-GE-400 engines. The engines are
low bypass, axial-flow, twin-spool turbofans with afterburner. The three stage fan
(low pressure compressor) and the seven stage high compressor are each driven by a single
stage turbine. The basic functions are supported by the engine driven accessory gearbox
which drives the engine fuel pump, variable exhaust nozzle (VEN/start) fuel pump, lubrication,
and oil scavenge pump, engine fuel control, and alternator. Fuel flow from the VEN/start
pump is used to drive the VEN actuator and provide initial fuel pressure the main engine start.
An inlet device is installed in each engine intake to reduce the aircraft radar signature and to
improve survivability.
2.1.1.1 FADEC - Full Authority Digital Engine Control
Engine operation is controlled by a full authority digital engine control (FADEC), mounted on the
engine casing. Each FADEC computer has two central processor units, channel A (CH A) and
channel B (CH B), and is integrated with the Mission Computers (MCs),
Flight Control Computer (FCCs), and throttles. Normally, both FADEC channels monitor engine
and control system operation with one channel in control and the other in standby. In the event of
a control system failure, the FADEC automatically selects the channel with better capability.
2.1.1.4.2 Throttles
Two throttles, one for each engine, are located on the left console. Throttle movement is
transmitted electrically to the corresponding FADEC for thrust modulation and to the FCCs for
auto-throttle operation. There is no mechanical linkage between the throttles and the engines.
During engine start, advancing the throttle from OFF to IDLE opens the engine fuel control
shutoff valves and, when commanded by the FADEC, provides fuel flow to the engines.
Afterburner operation is initiated by advancing the throttles through the MIL detent into the
afterburner range. During catapult launch or carrier touchdown, an afterburner lockout
mechanism extends to preclude inadvertent afterburner selection.
2.1.2 ATC- Automatic Throttle Control
The ATC system has two operating modes, approach and cruise. The system automatically
modulates engine thrust between flight IDLE and MIL power in order to maintain on-speed
angle of attack (AOA) in the approach or calibrated airspeed
(existing at the time of engagement) in the cruise mode.
2.2 Fuel System
The aircraft can also be configured as an airborne tankers with the carriage of a centerline
mounted air refueling store (ARS).
2.1.1Engine Feed System
Each engine feed system contains an airframe mounted accessory drive (AMAD) driven motive
flow/boost pump, a feed tank with an internal motive flow powered turbo pump, and an engine
shutoff valve. For survivability, the left and right feed systems are normally separated but can be
interconnected by a normally closed crossfeed valve and a normally closed feed tank
interconnect valve.
2.2.1.1 Motive Flow/Boosts Pump
Each AMAD drives a two-stage motive flow/boost pump. The first stageam of the fuel tank.
2.2.1.4 Crossfeed Valve
The crossfeed valve, normally closed, allow /> fuel to the motive flow system. Fuel from the motive flow system is used to cool accessories,
power the fuel tank turbo pumps and certain transfer/scavenge pumps, and control certain
transfer valve.
2.2.1.2 Feed Tanks
During normal operation, each engine receives fuel from separate fuel feed lines. A motive
flow powered turbo pump in each feed tank supplies fuel to its respective motive flow/boost
pump.
Each fuel tank has horizontal baffle which traps fuel, providing a minimum of 10seconds of
negative g flight at MAX power. No sustained zero g capability is provided, and prolonged
transitions through zero g (greater than 2 seconds) may produce a L and/or R BOOST LO
caution. If a feed tank pump fails, fuel is suction fed to the motive flow/boost pump. In this case,
flight at high altitude with high feed tank fuel temperatures may not supply enough fuel for high
power settings.
2.2.1.3 Feed Shutoff Valves
In the event of a fire or fuselage fuel leak, engine feed shutoff valves provide the capability to
isolate a fuel feed system immediately downstream of the fuel tank.
2.2.1.4 Crossfeed Valve
The crossfeed valve, normally closed, allows a single motive flow/boost pump to feed both
engines when boost pressure is lost on one side ( e.g., single engine shutdown, a leak,
motive flow/boost pump failure, or feed tank depletion.) A loss of boost pressure downstream of
the motive flow/boost pump sets the L or R BOOST LO caution and opens crossfeed valve.
2.3 FPAS - Flight Performance Advisory System
The flight performance advisory system (FPAS) is provided to aid the pilot in making time, fuel
and distance calculations.
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