There was a VERY nasty electrical emergency on the Wessex, around '87 - '89.
IIRC the bare bones were:
Cliff Winching exercise on Antrim coast
Winchman and "survivor" on winch
GENerator caption
FRC drills = Faulty GEN "OFF"
So, quite correctly, they did select it "Off"
Then it all went BANANAS!
Rotor RPM fluctuating (with lift then loss of lift), associated Yaw, mega captions
They ran the a/c onto the field ahead, not easy when power is changing constantly & you also have two guy's underneath - who were deposited safely!
Please sit down whilst you read the next bit:
The Wessex had been in service over 25 years but there was no routine service schedule for the generators / brushes!!
I think the GEN was either "S" or "U/S" & some lasted a long time after fit, without an overhaul.
Consequently, when one GEN started failing, it dragged the good GEN down (Power balancing circuit, designed to share load by bringing lower GEN up!)
The good GEN produced a caption (dragged-down), and once the good GEN was switched-off.....
The bad GEN was producing low volts and messing-up the system.
Cannot quite recall why the engine computers did not freeze with low volts.
(Maybe they did / did'nt / did / did'nt etc?)
Nasty-Nasty!
That said, the Wessex was a MIGHTY beast, with lots of far-ahead technology, bear in mind it was a 1950's design.
lsh
