TM  1-1520-240-10 2-3-8            d. RRPM droop compensation based on thrust le- ver position. e. Beep capability becomes active for load match to other engine. f. Full contingency power capability. g. Over temperature protection throughout opera- tion. h. Engine   shutdown   in   response   to   ECL   being placed at STOP i. Tracking of primary mode during normal primary mode operation allowing a smooth switchover when se- lected. If  in  reversionary  mode  for  any  reason  (training)  and there is a reversionary failure, the FADEC will not auto- matically switch back to the primary mode. The pilot must manually select PRI mode. CAUTION If both the primary and reversionary sys- tem fail, the engine remains at the fuel flow being used at the time of the failure. When a failed fixed fuel flow condition exists, the ECL and the beep trim switch for the af- fected   engine   is   inoperative,   therefore there is no proportional control through ECL except under some conditions STOP. Engine  shutdown  may  be  accomplished by moving the ECL from its present posi- tion to STOP. Under these conditions, the ENG 1 (2) FAIL and/or FADEC 1 (2) cau- tions are illuminated. NOTE If FADEC and/or REV and ENG FAIL lights are  illuminated  (which  signifies  a  fuel  flow fixed condition), toggling the PRI/REV switch reboots the microprocessor in the DECU. If it is a spurious fault, the lights extinguish except the REV light. If the hard fault is real, the REV and ENG FAIL lights illuminate again but not the FADEC light. When taking off with one engine in reversionary mode the  procedure  is,  before  lift-off,  the  engine  still  in  PRI mode is used to set the correct rotor speed via the FADEC NR% switch. The operator then uses the beep switch of the engine in reversionary mode to match en- gine torque. 2-3-31.  ENG COND Panel.  714A CAUTION When  adjusting  controls or switches on the  overhead  switch  panel,  make  sure gloves or sleeves do not catch and inad- vertently move the ENG COND levers. The ENG COND panel is located in the overhead switch panel (fig. 2-3-5). NO.1 and NO. 2 ENG COND Levers. The ENG COND Levers (ECL) provide the pilot with proportional accelera- tion and deceleration authority. The ECLS are spring- loaded  outboard  creating  a  gated  motion  when  ad- vanced from the STOP to GND and to FLT positions. ENG COND lever friction is provided to reduce the possi- bility  of  over-torque  transmissions  by  resisting  rapid movement of the levers. 2-3-32.  FADEC Panel.  714A The  FADEC  panel  is  located  on  the  overhead  switch panel (fig. 2-3-6). It comprises of the following: a. NR % Switch. The NR% switch controls a rheo- stat which allows the operator to select any RRPM be- tween 97% and 103%. There are detents at 97%. 100% and 103%. With the ECL(s) in FLT, NR will be maintained at the selected speed. 100% is the normal position. b. PRI/REV Switches. The primary mode is the nor- mal mode of operation. The REV (reversionary) mode is selected as a backup mode or is automatically selected if the primary system has a hard fault failure. A hard fault failure is defined as one in which normal primary system performance  might  be  jeopardized.  Other  failures  are classified as soft failures when the system is fault tolerant and can continue fully operational with the fault signal present. c. BU/PWR  Switch.  The  Back-Up  Power  switch when ON connects the aircraft battery relay and essen- tial relay. Figure  2-3-5.   Engine Condition Panel  714A