曝光台 注意防骗
网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者
WoffW Scheduled
with AOA
40° TED
(on-speed)
40° TED
(on-speed)
Figure 2-20. Flap Schedules
2.9.6 Speedbrake Function. The aircraft is not fitted with independent speedbrake surfaces. A
²speedbrake function² is provided to increase drag by partial deflection of several of the aircraft's
primary flight control surfaces: ailerons, rudders, TEFs, and spoilers. The stabilators are commanded
to counter pitch transients during speedbrake extension and retraction. The full speedbrake function
can only be commanded in UA.
At subsonic speeds in UA, the speedbrake function flares the rudders and symmetrically raises the
ailerons TEU to approximately 95% of the capability of each surface at the given flight conditions.
This makes sure approximately 5% of surface authority is available for yaw and roll control. If needed,
rudder and aileron priority is given to yaw and roll commands. TEFs are also symmetrically lowered
to further increase drag and to counter the loss of lift caused by deflecting the ailerons TEU. The
spoilers are raised to the full up 60° position only when the speedbrake command reaches 75%. At
subsonic speeds, the stabilator is used to offset any pitch transients that occur due to the deflection of
all speedbrake surfaces except the spoiler. Delaying spoiler deflection until 75% allows the pilot to use
partial speedbrakes for speed modulation, while avoiding minor spoiler induced pitch transients.
At supersonic speeds in UA, speedbrake surface deflections are changed. The rudders are not
deflected above 1.05 M due to vertical tail loads. The ailerons and TEFs are not deflected above 1.1 M
due to a lack of effectiveness. The spoilers are therefore deflected immediately upon speedbrake
actuation, since they are the only effective surface at these conditions. At supersonic speeds, the
stabilator is used to counter spoiler deployment. The speedbrake function is completely disabled above
1.5 IMN.
In UA, the speedbrake function is ramped out above 16° AOA or below -9° AOA to preserve
lateral-directional stability and between -3.0 to -1.5g for airframe loads.
In PA, the speedbrake function is disabled with WoffW. With WonW and the FLAP switch in HALF
or FULL, the speedbrake function only deploys the spoilers. While the spoilers can be deployed during
landing rollout or aborted takeoff, the drag increase is minimal, and rollout distance is not appreciably
A1-F18EA-NFM-000
I-2-64 ORIGINAL
decreased. With WonW and the FLAP switch in AUTO, full extension of the speedbrake function
commands 20° of rudder flare, 23° of TEU aileron, 7° of TED TEF, 60° of spoiler, and a 2° TED
stabilator change.
2.9.6.1 Speedbrake Switch. The speedbrake switch, located on the inboard side of the right throttle
grip, is used to enable/disable the speedbrake function, e.g., extend/retract the speedbrake surfaces.
The forward and center positions are detented, while the aft position is spring-loaded back to center
and must be held. In the F/A-18F (trainer configuration), the rear cockpit speedbrake switch has
override priority over the front cockpit switch.
Forward
(unmarked)
Retracts speedbrake surfaces (full retraction in 2 seconds).
Center
(unmarked)
Stops speedbrake surfaces at an intermediate position.
Aft
(unmarked)
Extends speedbrake surfaces (full extension in 2 seconds).
NOTE
· If the speedbrake switch is held or fails in the aft position for more
than 5 minutes, the speedbrake switch is declared failed, and the FCS
caution is set. If the switch is failed or is held in the aft position when
the FCS RESET button is pushed, the speedbrake surfaces are
retracted, Xs are set on the DEGD row of the FCS page, and the
speedbrake function is disabled for the remainder of the flight.
· If the front cockpit switch is held in the aft position during any FCS
RESET attempt, the speedbrake switch is declared failed; the speedbrake
surfaces are retracted; and the speedbrake function is disabled
for the remainder of the flight. This allows the speedbrake surfaces to
be retracted before the 5 minute timer expires, if the front cockpit
switch is stuck in the aft position.
· In the F/A-18F (trainer configuration), if the rear cockpit switch fails
in the aft position, the 5 minute timer must expire before the
speedbrake surfaces can be retracted with the FCS RESET button.
2.9.6.2 SPD BRK Light. The green SPD BRK light is located on the left warning, caution, and
advisory panel on the main instrument panel. The SPD BRK light comes on anytime the speedbrake
surfaces are not fully retracted.
2.9.7 G-Limiter Considerations. In order to understand what protection the aircraft's g-limiter
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
NATOPS Flight Manual 飞行手册 1(63)
