Three Axis Trim Indicator

Technical Information

Catalogue No: C0567
Category: Flight Control
Object Type: Indicator/Instrument
Object Name: Three Axis Trim Indicator
Part No: 4559-A-1
Serial No: 6011130
Manufacturer: Bendix
Division: Eclipse-Pioneer [of Bendix]
Platform(s): VC10 
Year of Manufacture: Unknown
Width (mm):
Height (mm):
Depth (mm):
Weight (g):
Location: Archive Object Store

Ref No 6TK13
Indicator - Three-Axis Trim
S.A.E. Spec AS 402 TSO-C98
Rating 1-0-1 volts 1000 ohms per volt approx.
Wt. Lbs. 1
Serial No. 6011130
The Bendix Corporation
Eclipse-Pioneer Division
Teterboro, New Jersey
Made in USA
Converted from Bendiix Type 15101-1F-A5 to Elliott Type 4559-A-1.
Model 1883
Type 10H
Weston Elec. Inst. Corp., U.S.A.


The Three-Axis Trim Indicator has a dual function to display trim conditions.:
• To display any commands held in the system in the form of a signal applied to the torque motors prior to the autopilot engagement.
• To show “feel out-of-trim condition of the aircraft while under autopilot control.
Automatic disconnection of an autopilot system is indicated by a flashing red lamp. The power for this lamp is normally derived from the aircraft 28V d.c. supply. In the event of failure of this (normal) 28V d.c. supply, the warning lamp circuit is automatically transferred to the auto pilot internal 28V d.c. (unfiltered) supply.
Under this alternative supply condition, the warning lamp changes its role and operates as an indicator: it provides a steady red light when the autopilot is engaged and is extinguished in the event of autopilot failure.
The autothrottle warning lamp provides a steady amber light when an unacceptable difference exists between the Air Data Sensor signal and the Comparison Air Data Sensor monitoring signal or when the difference between the incoming air speed signal varies more than 8 knots from the selected speed on the autothrottle controller. This warning signal also appears when the power switch is on and the selector switch is off.
The glideslope arming indicator lamp shows a blue light when the glideslope system is armed. A steady amber light from the glideslope ENGAGED lamp indicates that the glideslope signal has been captured and held.

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