STANDBY ARTIFICIAL HORIZON Mk. 6H

LEADING PARTICULARS

Stores Ref. No.:6A/6819
Connection:104 Pattern / Plessey Mk. 4, medium body 12-way
Manufacturer:Ferranti
Attachment:No.6 UNC screws

DESCRIPTION

This artificial horizon is used as a backup to the main attitude indicator.

The Mk. 6 range of artificial horizons all contain a motor driven gyro, mounted on an inner gimbal which pivots in the "pitch" axis. This inner gimbal is mounted within an outer gimbal which pivots in the "roll" axis. The gyro is initially erected when on the ground, but can be re-erected in level flight if it wanders off by pressing the "PUSH FOR FAST ERECTION" button.

A less forceful degree of automatic gyro erection is constantly active, where tilt switches sense if the gimbals are not true to level, these switches apply power to torque motors that encourage the gyro back to the vertical at a gentler rate than by using the fast erection button.

Electrical connections are made between moving parts by slip rings.

SIMULATION

I was lucky to acquire an example of the simulator artificial horizon instrument from the Lightning training simulators. This instrument is a close representation of the real Mk. 6H, but actually shares no parts with the real thing.

Had I been trying to use an original Mk. 6, it would have entailed applying modifications to operate the moving parts; the simulator instrument is built with DC motors for motion control.

REFERENCES

Indicator general and technical information:
AP112G-0306-16, Chapter 1-1, A.L.1, Nov. 1967, Artificial Horizon Mk. 6 (series)
AP112G-0306-16, Chapter 1-9, A.L.1, Feb. 1971, Artificial Horizon Mk. 6H

AP112G-0306-16, Chapter 4-1, A.L.6, Mar. 1972, Artificial Horizon Mk. 6 (series) - Repair & Reconditioning
AP112G-0306-16, Chapter 4-9, A.L.7, Aug. 1974, Artificial Horizon Mk. 6H - Repair & Reconditioning

Control box general and technical information:
AP112G-0304-16, A.L.6, Sept. 1976, Artificial Horizon Control Box Types A and B

T Mk.5 electrical "Vol. 1":
A.P.101B-1005-1B, Sect. 7, Chapter. 5, A.L.60, Nov 1973, Flight Instruments - Paragraph 20

F Mk. 3, T Mk. 5 and F Mk. 6 aircrew manual:
A.P.101B-1003, 5 & 6A, Part 1, Chapter 7, A.L.2, Nov. 1984 - Instruments - Paragraph 41