TM 1–1520–238–T–3
Change 4
3–19
3–81 SIGNAL NAME:
COLL VALVE CMD MONITOR (ACY) CLTV VLV MON STAT (ACZ)
MEMORY LOCATION: 002105
MEMORY DATA BIT(S):
7
(BINARY)
CONDITION:
(None)
SIGNAL FUNCTION:
Indicates capability of the collective stability augmentation system (SAS)
sleeve to return to center position after a BUCS self test or a ground FD/LS has
been performed or the presence of an electromagnetic interference (EMI) on
the electro–hydraulic valve (EHV) lines which induced a voltage greater than 2
VAC on the collective EHV lines (associated with a particular coordinate axis
when BUCS is not engaged in that axis) during a DASE test.
REMARKS: From DASEC to FCC.
PASS:
If fifth digit displayed on HOD is 0, go to paragraph 3–82.
FAIL: Location of fault: collective (vertical) servoactuator, wiring from DASEC to collective (vertical)
servoactuator electro–hydraulic valve. Troubleshoot wiring to isolate fault
(TM 1–1520–238–T–7).
3–82 SIGNAL NAME:
COLL A–B MISTRACK (ACY) CLTV ACTR STAT (ACZ)
MEMORY LOCATION: 002105
MEMORY DATA BIT(S):
8
(BINARY)
CONDITION:
(None)
SIGNAL FUNCTION:
Indicates that the collective A and B actuators are tracking each other within a
tolerance of 9% to 19%.
REMARKS: From DASEC to FCC.
PASS:
If fourth digit displayed on HOD is 0, 1, 2, or 3, go to paragraph 3–83.
FAIL: Location of fault: collective (vertical) servoactuator LVDTs, wiring from DASEC to collective
(vertical) servoactuator LVDTs. Troubleshoot wiring to isolate fault (TM 1–1520–238–T–7).
3–83 SIGNAL NAME:
YAW A–B MISTRACK (ACY) YAW ACTR MISTRK (ACZ)
MEMORY LOCATION: 002105
MEMORY DATA BIT(S):
9
(BINARY)
CONDITION:
(None)
SIGNAL FUNCTION:
Indicates that the yaw A and B actuators are tracking each other within a
tolerance of 9% to 19%.
REMARKS: From DASEC to FCC.
PASS:
If fourth digit displayed on HOD is 0 or 1, go to paragraph 3–84.
FAIL: Location of fault: tail rotor servoactuator LVDTs, wiring from DASEC to tail rotor servoactuator
LVDTs. Troubleshoot wiring to isolate fault (TM 1–1520–238–T–7).
3–84 SIGNAL NAME:
ROLL A–B MISTRACK (ACY) ROLL ACTR MISTRK (ACZ)
MEMORY LOCATION: 002105
MEMORY DATA BIT(S):
10
(BINARY)
CONDITION:
(None)
SIGNAL FUNCTION:
Indicates that the roll A and B actuators are tracking each other within a
tolerance of 9% to 19%.
REMARKS: From DASEC to FCC.
PASS:
If fourth digit displayed on HOD is 0, go to paragraph 3–85.
FAIL: Location of fault: lateral (roll) servoactuator LVDTs, wiring from DASEC to lateral (roll)
servoactuator LVDTs. Troubleshoot wiring to isolate fault (TM 1–1520–238–T–7).
