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Old 29th Sep 2022, 04:20
  #36 (permalink)  
JGtn
 
Join Date: Jun 2019
Location: Brisbane
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That a very good comment, in dead.
The Electrical fire/smoke procedure ask you to segregate the power source to the Essentials in order to determine which source is feeding the Ess buses, powering it alternatively from the Batteries or the Generators. You have to switch OFF both BATTERY MAIN and MASTER successively in conjunction with the GEN 1-2, if mixed up, not only you loose the ESS but the complete cockpit!
That might explain the AFCS issues, as it will be then inoperative.
The landing Gear needs the Essentials to be controlled, ESS1 normal operation, ESS2 emergency operation, if the electrical power is lost before the control, it free falls without locking itself down, may be the nose wheel thanks to the airflow, but certainly not the main ones.
The EEC are permanently electrically self-sustain by their own PMAs from 40% NR no need of the essential. If the IDLE and FLT mode were operating the EEC were perfectly alive.
May be because of a collective control torque tubes and rode issue/rupture to the mixing unit, explaining the impossibility to control the main rotor speed from the cockpit has lead the crew to play with the FLT/IDLE mode to control the engine power and then modulate between Power ON / Power Off.
It will have been difficult to do so with the ECL in manual and no indications in the cockpit. At least in AUTO GOV the engine power can controlled between two know power, IDLE and 100(102)% NR.

In any case, good job having landed this aircraft without human injuries.
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