I guess your photo was taken without the “115V AC” switched on. (In the Vulcan this came from the 200V supply via transformers.) That would account for the MFS Power Failure Indicator being illuminated and the red “Attitude Failure Flag” showing in the Stbd Director Horizon. If the 115V power was on when the photo was taken then it’s a whole different scenario!
Did one or both (port and starboard) Director Horizons show any movement or attempt to oscillate and erect when the power was switched on?
Since the MFS Power Failure Indicator is illuminated and the red “Attitude Failure Flag” is showing then perhaps some of the fuses have failed (there were both aircraft fuses and fuses in the large MFS Junction Box) and this has been detected by the “Single Phase Supply Monitor” (a torque switch) which has then interrupted the DC and operated the light.
If the port (pilot’s) DH did erect then the co-pilot’s attitude failure flag could be on because there is, probably, a difference in the port and starboard DH roll and/or pitch indications, again perhaps due to a power supply failure to the starboard system.
However assuming the photo was taken “power off” but that you know that one or both of the attitude systems failed to run up when power was applied then I would guess that one or more of the time delays in the Erection Switching Unit has failed to switch at 20 seconds and thereby failed to remove the boosted supplies. This would probably result in damage to the gyro erection motors and/or the gyro motor itself since they were designed originally to run on lower voltages.
As sealed units, they are difficult to get into! And even if you could, then replacement of the motor windings is probably impractical and that even if you had replacement windings.
But continuity and resistance checks on the gyros themselves may give some clues! Especially if you have one reasonable gyro to compare readings against.
I do not have any spare gyros, Director Horizons or an Erection Switching Unit, though I may have a good Comparator Unit if you need it.
Some circuits I do have which I can email as attachments.
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