Flight with flaps FULL has not been demonstrated due to limited nose-up control authority from
the remaining good stabilator.
WARNING
· Do not select flaps FULL for landing with a failed stabilator, because
longitudinal control authority may be insufficient for landing.
· With a failed stabilator, do not exceed 10° AOA in AUTO flaps with
wing stores or wing tanks. Do not select flaps FULL for landing with a
failed stabilator, because longitudinal control authority may be insufficient
for landing.
11.4.4 GAIN ORIDE. While not a failure mode, GAIN ORIDE is prescribed for certain AOA or
pitot-static sensor failures to provide better or more predictable handling qualities (see Warning/
Caution/Advisory Displays, figure 12-1). With flaps AUTO, selecting GAIN ORIDE results in fixed
gains that correspond to 0.80 Mach, 39,000 feet, and 250 KCAS. Longitudinal and lateral response is
slightly more sluggish as airspeed is reduced below these values and is slightly more sensitive as
airspeed is increased above these values. Regardless, handling qualities remain very good within the
10° AOA and 350 KCAS NATOPS limits for GAIN ORIDE operation. If the airspeed limit is exceeded,
self-sustained pitch oscillations will start to occur above 375 KCAS, and the aircraft will become
uncontrollable above 450 KCAS due to the fixed air data values in the flight control system gains. If
the AOA limit is exceeded, departures are likely since the fixed values of the air data and AOA severely
reduce departure resistance. Additionally, the aircraft will stall at a higher than normal airspeed due
to the fixed position of the LEFs.
With flaps HALF or FULL, GAIN ORIDE results in fixed gains that correspond to 8.1° AOA and
500 feet; handling qualities are best at these conditions and degrade slightly away from on-speed AOA.
At higher airspeeds in 1g flight, the aircraft will stabilize at lower than normal AOA, due to the TEF
position frozen at higher than normal deflections. While not dangerous, this characteristic is
uncomfortable. Also, at higher airspeeds, higher than normal aft stick force is required to maintain
flight path while in a turn. Flight is prohibited above 190 KCAS (flaps FULL) or 200 KCAS (flaps
HALF) due to these characteristics. Flight is also prohibited above 10° AOA due to the reduced stall
margin available with fixed LEF deflections.
Transition to or from landing configuration should be done in level flight at 180 KCAS. Transition
should not be made while in a bank due to the higher than normal aft stick forces required to maintain
flight path angle. Sideslip excursions may also occur if flap transition is made in a turn.
Carrier based flight tests (GAIN ORIDE/flaps HALF) demonstrated satisfactory approach handling
qualities. The aircraft remained easily controllable, though increased pilot attention to the landing task
was required. During descent, small inputs were required to maintain proper pitch attitude.
Approaches flown at conditions other than on-speed resulted in sluggish handling qualities.
11.4.5 AHRS FAILURE FLYING QUALITIES
An AHRS channel failure is defined as the loss of both rate and acceleration data (Xs in CAS P, CAS
R, CAS Y, N ACC, and L ACC). Single or dual channel AHRS failures should have no adverse effect
on flying qualities. If a third channel failure is detected, all four channels will be Xd out because the
FCCs will be unable to confirm which channel is providing valid data. If the third failure can be isolated
to a particular channel, all four channels will be Xd out but the flying qualities will be unaffected with
A1-F18EA-NFM-000
IV-11-11 ORIGINAL
the exception of a small degradation to the g-limiter. If a third failure occurs but is not detected (two
columns of Xs), or is detected but not isolated to a particular channel (four columns of Xs), flying
qualities will be somewhat degraded. When flying qualities are degraded due to AHRS channel failures,
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本文链接地址：NATOPS Flight Manual 飞行手册 2(11)
