Originally Posted by
Basil
What effect does switching on engine anticing have on ice crystal icing?
According to the proposed AD:
These
conditions can cause ice crystals to
accumulate in the core flow path of the
engine during low-power conditions,
such as idle or idle descent. The
accumulated ice sheds during throttle
increase and is ingested into the engine,
causing the combustor to flameout
resulting in an in-flight flameout and
potential damage to the high pressure
compressor due to ice impact. The GE
CF6–80C2 and CF6–80A series engines
models have similar compressor
designs.
Activating the engine anti-ice
increases the flameout margin and
reduces the potential for multiple
engine flameouts by increasing bleed
flow and idle speed. Engine anti-ice also
assists with relighting the engines by
turning on the igniters on airplanes that
are not equipped with autorelight.
However, in several of the subject
engine flameout events, the engine antiice
was already on when the engines
flamed out. In each flameout event, the
engines relit and continued to operate
normally for the remainder of the flight.