E135/146 Anti Ice SOP

[balaton]

Hi Embraer guys,

A question about the use of anti-ice system on the 135/145:
By your SOP, do you switch on the a/i sytem manually before entering ice condition (for e.g. descending into visible moisture with TAT in the icing range) or you just wait for the automatics to kick in?
Many thanks,
balaton

[Condor]

For normal in flight operations the Ice Detection Override knob would be left at AUTO (which will turn on both Engine and Airframe anti-icing if ice is detected). However if ice accretion is observed on windscreen/wipers and the system has not operated then the policy is to put the Override knob to ALL which turns on the anti-icing protection. (There was a case a number of years ago where the sensors did not operate in time resulting in an autopilot disconnect and a rapid roll - hence this policy).

Having said that normally the Auto system works just fine.

Slightly different procedures for ground ops and take off in icing conditions below 1500' - in this case the Ice Detection Override knob is placed to ENG thus turning on engine anti-icing protection without relying on Auto sensing. Goes back to AUTO in the after take-off checks.