You select the engine anti-ice valve to the ON position. The COWL VALVE OPEN light is illuminated blue and the TAI indication illuminates on the CDS. What happened?
A.A.This is a normal indication.
B.B.There is excessive pressure in the duct leading from the cowl anti-ice valve to the cowl lip.
C.C.There is excessive heat applied to the cowl lip.
D.D.The cowl anti-ice valve fails to move to the position commanded by the ENG ANTI-ICE switch.
正确答案是D