The F-22's cockpit is one of the very first "all-glass"
cockpits for tactical fighters - there are no traditional round
dial, standby or dedicated gauges. It accommodates the largest range
of pilots (the central 99 percent of the Air Force pilot population)
of any tactical aircraft. It is the first baseline "night
vision goggle" compatible cockpit, and it has designed-in
growth capability for helmet-mounted systems. The canopy is the
largest piece of polycarbonate formed in the world with the largest
Zone 1 (highest quality) optics for compatibility with
helmet-mounted systems. While functionality is critical, the F-22's
cockpit design also ensures pilot safety with an improved version of
the proven ACES II ejection seat and a new pilot personal equipment
and life support ensemble.
The F-22's cockpit represents a
revolution over current "pilot offices", as it is designed
to let the pilot operate as a tactician, not a sensor operator.
Humans are good differentiators, but they are poor integrators. The
F-22 cockpit lets the pilot do what humans do best, and it fully
utilizes the power of the computer to do what it does best.
Using the power of the onboard computers, coupled with the extensive
maintenance diagnostics built into the F-22 by the maintainers, that
workload has been significantly reduced. The idea is to relieve
pilots of the bulk of system manipulations associated with flying
and allow them to do what a human does best - be a tactician.
Aircraft startup and taxi are excellent
examples of harnessing the power of the computer to eliminate
workload. There are only three steps to take the F-22 from cold
metal and composites to full-up airplane ready for takeoff: The
pilot places the battery switch 'on,' places the auxiliary power
unit switch momentarily to 'start' and then places both throttles in
'idle.' The engines start sequentially right to left and the
auxiliary power unit then shuts down. All subsystems and avionics
are brought on line and built-in testing checks are made. Then the
necessary navigation information is loaded and even the pilot's
personal preferences for avionics configuration is read and the
systems are tailored to those preferences. All of this happens
automatically with no pilot actions other than the three steps. The
airplane can be ready to taxi in less than 30 seconds after engine
start.
Pilot/Vehicle Interface
The GEC-built Head-Up Display (HUD) offers a wide field of view (30
degrees horizontally by 25 degrees vertically) and serves as a
primary flight instrument for the pilot. The F-22's HUD is
approximately 4.5 inches tall and uses standardized symbology
developed by the Air Force Instrument Flight Center. It does not
present information in color, but the tactical symbol set is the
same that is used on the F-22's head down displays (HDDs).
During F-22 canopy birdstrike tests, it was found that the HUD
combiner glass would shatter the canopy. To solve this problem for
EMD, the F-22 HUD will have a rubber buffer strip on it that will
effectively shield the polycarbonate of the canopy when it flexes
during a birdstrike from hitting the optical glass in the HUD and
shattering. Design is also underway for a HUD that will collapse
during a birdstrike, but would remain upright under all other
conditions. Additionally, the team is investigating the possibility
of having the HUD combiner glass laminated similar to household
safety glass to preclude flying glass in the cockpit following
birdstrike.
The Integrated Control Panel (ICP) is
the primary means for manual pilot data entry for communications,
navigation, and autopilot data. Located under the glareshield and
HUD in center top of the instrument panel, this keypad entry system
also has some double click functions, much like a computer mouse for
rapid pilot access/use.
There are six liquid crystal display (LCD) panels in the cockpit.
These present information in full color and are fully readable in
direct sunlight. LCDs offer lower weight and less size than the
cathode ray tube (CRT) displays used in most current aircraft. The
lower power requirements also provide a reliability improvement over
CRTs. The two Up-Front Displays (UFDs) measure 3"x4" in
size and are located to the left and right of the ICP. The UFDs are
used to display Integrated Caution/Advisory/Warning (ICAW) data,
communications/navigation/identification (CNI) data and serve as the
Stand-by Flight instrumentation Group and Fuel Quantity Indicator (SFG/FQI).
The Stand-by Flight Group is always in operation and, although it is
presented on an LCD display, it shows the basic information (such as
an artificial horizon) the pilot needs to fly the aircraft. The SFG
is tied to the last source of power in the aircraft, so if
everything else fails, the pilot will still be able to fly the
aircraft.
The Primary Multi-Function Display (PMFD)
is a 8"x8" color display that is located in the middle of
the instrument panel, under the ICP. It is the pilot's principal
display for aircraft navigation (including showing waypoints and
route of flight) and Situation Assessment (SA) or a "God's-eye
view" of the entire environment around (above, below, both
sides, front and back) the aircraft.
Three Secondary Multi-Function Displays
(SMFDs) are all 6.25" x 6.25" and two of them are located
on either side of the PMFD on the instrument panel with the third
underneath the PMFD between the pilot's knees. These are used for
displaying tactical (both offensive and defensive) information as
well as non-tactical information (such as checklists, subsystem
status, engine thrust output, and stores management).
Integrated Caution, Advisory and Warning System (ICAW)
To reduce pilot workload in flight, the
F-22 incorporates the uniquely designed integrated caution, advisory
and warning system (ICAW). This system's messages normally appear on
the 3-by-4 inch up-front display just below the glare shield. A
total of 12 individual ICAW messages can appear at one time on the
up-front display and additional ones can appear on sub pages of the
display.
More than two years of detail design by
pilots and engineers has gone into the filtering logic of the ICAW
system and extensive testing of the system was done. In addition,
the success of the Army's RAH 66 Comanche helicopter's ICAW system
that uses a similar filtering approach gives the F-22 team
confidence in the fundamental soundness of the design.
Two aspects of the ICAW display
differentiate it from a traditional warning light panel. First, all
ICAW fault messages are filtered to eliminate extraneous messages
and tell the pilot specifically and succinctly what the problem is.
For example, when an engine fails, the generator and hydraulic
cautions normally associated with an engine being shutdown are
suppressed, and the pilot is provided the specific problem in the
form of an engine shutdown message.
The second is the electronic checklist.
When an ICAW message occurs, the pilot depresses the checklist push
button (called a bezel button) on the bottom of the UFD and the
associated checklist appears on the left hand Secondary
Multi-Function Display (SMFD). This function also provides access to
non-emergency checklists for display to the pilot. In addition to
the visual warning on the display, the aircraft has an audio system
that alerts the pilot. A Caution is indicated only by the word
"caution", while a Warning is announced with the specific
problem - that is, "Warning. Engine Failure".
If multiple ICAWs occur, their
associated checklists are selected by moving a pick box over the
desired ICAW and depressing the checklist button. Associated
checklists are automatically linked together so that if an engine
failure occurs, the pilot will not only get the checklist for the
engine failure procedure in-flight but also the single engine
landing checklist. The pilot can also manually page through the
checklists at any time from the main menu. This is particularly
handy when helping a wing man work through an emergency.
Cockpit Display Symbology
The tactical information shown on the displays is all intuitive to
the pilot-he can tell the situation around him by a glance at the
screen. Enemy aircraft are shown as red triangles, friendly aircraft
are green circles, unknown aircraft are shown as yellow squares, and
wingmen are shown as blue F-22s. Surface-to-air missile sites are
represented by pentagons (along with an indication of exactly what
type missile it is) and its lethal range. In addition to shape and
color, the symbols are further refined. A filled-in triangle means
that the pilot has a missile firing-quality solution against the
target, while an open triangle is not a firing-quality solution. The
pilot has a cursor on each screen, and he can ask the aircraft's
avionics system to retrieve more information. The system can
determine to a 98% probability the target's type of aircraft. If the
system can't make an identification to that degree, the aircraft is
shown as an unknown. Likewise, one of the original objectives
for the F-22 was to increase the percentage of fighter pilots who
make "kills".
The Inter/Intra Flight Data Link (IFDL)
is one of the powerful tools that make all F-22s more capable. Each
F-22 can be linked together to trade information without radio calls
with each F-22s in a flight or between flight. Each pilot is then
free to operate more autonomously because, for example, the leader
can tell at a glance what his wing man's fuel state is, weapons
remaining, and even the enemy aircraft targeted. Classical tactics
based on visual "tally" (visual identification) and
violent formation maneuvers that reduce the wing man to
"hanging on" may have to be rethought in light of such
capabilities.
Hands-On Throttle and Stick (HOTAS)
The F-22 features a side-stick controller (like an F-16) and two
throttles that are the aircraft's primary flight controls. The
GEC-built stick is located on the right console and there is a
swing-out, adjustable arm rest. The stick is force sensitive and has
a throw of only about one-quarter of an inch. The throttles are
located on the left console. Both the stick and the throttles are
high-use controls during air combat. To support pilot functional
requirements, the grips include buttons and switches (that are both
shape and texture coded) to control more than 60 different
time-critical functions. These buttons are used for controlling the
offensive (weapons targeting and release) and defensive systems
(although some, like chaff and flares, can operate both
automatically and manually) as well as display management.
Accommodations
Previous fighter cockpits were sized to accommodate the 5th
percentile to 95th percentile pilots (a range of only 90%). The F-22
cockpit is sized to accommodate the 0.5 percentile to 99.5
percentile pilots (the body size of the central 99% of the Air Force
pilot population) This represents the largest range of pilots
accommodated by any tactical aircraft now in service. The rudder
pedals are adjustable. The pilot has 15-degree over-the-nose
visibility and excellent over-the-side and aft visibility as
well.
Lighting
The cockpit interior lighting is fully
Night Vision Goggle (NVG) compatible, as is the exterior lighting.
The cockpit panels feature extended life, self-balancing,
electroluminescent (EL) edge-lit panels with an integral
life-limiting circuit that runs the lights at the correct power
setting throughout their life. It starts at one-half power and
gradually increases the power output to insure consistent panel
light intensity over time. As a result, the cockpit always presents
a well-balanced lighting system to the pilot (there is not a mottled
look in the cockpit). The panels produce low amounts of heat and
power and are very reliable. The aircraft also has integral position
and anti-collision lights (including strobes) on the wings. The low
voltage electroluminescent formation lights are located at critical
positions for night flight operations on the aircraft (on the
forward fuselage (both sides) under the chine, on the tip of the
upper left and right wings, and on the outside of both vertical
stabilizers. There are similar air refueling lights on the butterfly
doors that cover the air refueling receptacle.
Life Support Ensemble
The F-22 life support system integrates all critical components of
clothing, protective gear, and aircraft equipment necessary to
sustain the pilot's life while flying the aircraft. In the past,
these components had been designed and produced separately. The life
support system components include:
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An on-board oxygen generation
system (OBOGS) that supplies breathable air to the pilot.
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An integrated breathing
regulator/anti-g valve (BRAG) that controls flow and pressure to
the mask and pressure garments.
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A chemical/biological/cold-water
immersion (CB/CWI) protection ensemble.
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An upper body counterpressure
garment and a lower body anti-G garment acts a partial pressure
suit at high altitudes.
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An air-cooling garment, which is
also going to be used by pilots on the Army's RAH-66 Comanche
helicopter provides thermal relief for the pilot.
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Helmet and helmet-mounted systems
including C/B goggles and C/B hood; and the MBU-22/P breathing
mask and hose system.
The Boeing-led life support development and its suppliers designed
the life support system with the F-22's advanced performance
capabilities in mind. The separate components of the life-support
system must simultaneously meet pilot protection requirements
established by the Air Force in the areas of higher altitude flight,
acceleration, heat distress, cold water immersion, chemical and
biological environments, fire, noise, and high-speed/high-altitude
ejection. Escape-system tests have demonstrated that the
life-support system will protect pilots when exposed to wind speeds
of up to 600 knots. Current life-support systems are designed to
provide protection only up to 450 knots.
The head mounted portions of the
life-support system are approximately 30 percent lighter than
existing systems, which improves mobility and endurance time for
pilots. With its advanced design, the HGU-86/P helmet that will be
used by F-22 pilots during EMD reduces the stresses on a pilot's
neck by 20 percent during high-speed ejection compared to the
current HGU-55/P helmets. The F-22 helmet fits more securely as the
result of an ear cup tensioning device and is easily fitted to a
pilot's head. The helmet provides improved passive noise protection
and incorporates an Active Noise Reduction (ANR) system for superior
pilot protection.
The chemical/biological/cold water
immersion garment is to be worn by pilots when they fly over large
bodies of cold water or into chemical/biological warfare situations.
These garments meet or exceed Air Force requirements. During cold
water immersion tests, the body temperature of test subjects wearing
the garments fell no more than a fraction of a degree after sitting
in nearly 32-degree Fahrenheit water for two hours. Current CWI
suits allow body temperatures to drop below the minimum of 96.8
degrees F within an hour and a half. Normal body temperature is 98.6
degrees F. Other advantages of the F-22 life support system include
its ability to fit a wider range of sizes and body shapes (the
central 99% of the US Air Force pilot population).
Canopy
The F-22's canopy is approximately 140 inches long, 45 inches wide,
27 inches tall, and weighs approximately 360 pounds. It is a
rotate/translate design, which means that it comes down, slides
forward, and locks in place with pins. It is a much more complex
piece of equipment than it would appear to be.
The F-22 canopy's transparency (made by Sierracin) features the largest piece of monolithic polycarbonate material being formed today. It has no canopy bow and offers the pilot superior optics (Zone 1 quality) throughout (not just in the area near the HUD) and it offers the requisite stealth features.
The canopy is resistant to chemical/biological and environmental agents, and has been successfully tested to withstand the impact of a four-pound bird at 350 knots. It also protects the pilot from lightning strikes.
The 3/4" polycarbonate transparency is actually made of two 3/8" thick sheets that are heated and fusion bonded (the sheets actually meld to become a single-piece article) and then drape forged. The F-16's canopy, for comparison, is made up of laminated sheets. A laminated canopy generally offers better birdstrike protection, and because of the lower altitude where the F-16 operates, this is an advantage. However, lamination also adds weight as well as reduced optics.
There is no chance of a post-ejection canopy-seat-pilot collision as the canopy (with frame) weighs slightly more on one side than the other. When the canopy is jettisoned, the weight differential is enough to make it slice nearly ninety degrees to the right as it clears the aircraft.
In testing so far, the cockpit canopy has fallen far short of its service life requirement according to DOT&E.
ACES II Ejection Seat
The F-22 uses an improved version of the ACES II (Advanced Concept Ejection Seat) ejection seat that is used in nearly every other Air Force jet combat aircraft (F-16, F-117, F-15, A-10, B-1, B-2). The seat has a center mounted (between the pilot's legs) ejection control. The F-22 version of the McDonnell Douglas-built ACES II includes several improvements over the previous seat models. These improvements include:
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The addition of an active arm restraint system to eliminate arm flail injuries during high speed ejections.
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An improved fast-acting seat stabilization drogue parachute system to provide increased seat stability and safety for the pilot during high-speed ejections. The drogue is located behind the pilot's head, rather than in the back of the seat and is mortar-deployed.
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A new electronic seat and aircraft sequencing system that improves the timing of the various events that have to happen in order for the pilot to eject (initiation, canopy jettison, and seat catapult ignition).
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A larger oxygen bottle gives the ejecting pilot more breathing air to support ejection at higher altitudes (if required).
The F-22 ACES II ejection system utilizes the standard analog three-mode seat sequencer that automatically senses the seat speed and altitude, and then selects the proper mode for optimum seat performance and safe recovery of the pilot. Mode 1 is low speed, low altitude; Mode 2 is high speed, low altitude; and Mode 3 is high altitude.
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