TM 1-1520-240-109-1-28 Figure 9-1-9. Ditching Exits9-1-73. Flight Controls.9-1-74. Longitudinal Cyclic Trim (LCT) SystemFailure.Should the system fail during cruise, with the cyclic trimsystem programmed for maximum forward tilt of the ro-tors, an abnormal nose-up attitude will result with de-creasing airspeed. Should one or both cyclic actuatorsfail in full retract position, airspeed must be limited ac-cording to Vne for retracted longitudinal cyclic trim. Withboth LCTs partially or fully retracted, maintain below Vneand if failure occurs extended, maintain airspeed at orabove 60 KIAS or until the approach to landing. Shouldthe longitudinal cyclic trim system fail, perform the follow-ing:CYCLIC TRIM circuit breakers — In. If cyclic trim opera-tion is not restored, proceed with the procedures belowfor AUTO or MANUAL modes of operation.If in AUTO mode:1. Airspeed—Adjust.2. CYCLIC TRIM switch — MANUAl.3. FWD and AFT CYCLIC TRIM switches —Adjust for airspeed.If LCT operation isnotindicated:FWD and AFT CYCLIC TRIM switches — RET for 30seconds, before landing.If in MANUAL mode:1. Airspeed—Adjust.2. CYCLIC TRIM switch — AUTO.If normal LCT operation isnot indicated:1. CYCLIC TRIM switch — MANUAl.2. FWD and AFT CYCLIC TRIM switches —RET both LCTS for 30 seconds, before land-ing.If both actuators are retracted, the landing will be normal.If one or both actuators fail in extended position, the pitchatitude of the helicopter will be higher than normal duringthe approach and will be dependent upon the amount ofactuator extension at the time of the failure. Execute ashallow approach to a hover or to the ground with anormal touchdown, avoiding large cyclic changes. Whenthe aft gear areon the ground, apply brakes and lower thenose. As the forward gear touch the ground, the aircraftwill tend to accelerate more than normal.Continue to ap-ply brakes as necessary to prevent forward movement.If the helicopter is taxied with the actuators failed in theextend position, use minimum control applications andadjust the thrust control at ground detent or higher. Thereis an increased susceptibility to droop-stop poundingwith this condition.9-1-75. Single AFCS Failure — Both Selected. A malfunction of the AFCS can usually be detected by anabrubt attitude change (hardover) or unusual oscilationsin one or more of the flight control axes or by lighting ofthe NO.1 or NO. 2 AFCS OFF caution. If flight is con-ducted at low altitude such as contour or NOE, a climb tohigher altitude must be iniated before the pilot attemptsisolation of the defective system.1. Airspeed —Reduce to 100 KIAS or Vne,whichever is slower.2. Altitude —Adjust as required.NOTEA hardover in the opposite direction may oc-cur when the malfunctioning AFCS is turnedoff and the functioning AFCS reacts on theflight controls.3. AFCS SYSTEM SEL switch— Isolatedefective system. Turn NO. 1 ON, if notisolated, turn NO. 2 ON.If systemisnot isolated:AFCSSYSTEMSELswitch —OFF.
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