Throttle hold or throttle cut. It can be done on the 9303.
One way is to set up a mix:
Pmix #5
THRO -> THRO
Pos 0 0%/0%
Pos 1 -100%/-100%
Offset -200
AIL POS0
GER POS0
RUD POS0
MMIX POS1
THR STK INH
.................................................. .................................................. ..........
Another way is In the System TRIM SET menu set the throttle to 0%.
In the Function list THRO CURV menu highlight Pos.0 under [THRO CURV] and set it to Pos.1
Highlight SW SELECT and set MIX to Pos1
Go to Point-3 highlight it and set it to 0.0%
Go to Point-H highlight it and set it 0.0%