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: 6011150
Manufacturer: Bendix
Division: Unknown
Platform(s): VC10 
Year of Manufacture:
Width (mm):
Height (mm):
Depth (mm):
Weight (g):
Location: Archive Object Store

Indicator Three Axis Trim


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.
The unit was made under licence from Bendix and was converted from Bendiix Pt No. 15101-1F-A5. Weston Elec Inst Corp U.S.A. Model 1883, Type 104

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