Originally Posted by BOAC
- IF you 'turn it on' IAW your ops manual (or at least all the ones I know of) you will never 'anti-ice' the wings! Strictly not advised.
Actually it is written in the OPS manual....
"Use
wing anti-ice during all ground operations between engine start and takeoff when icing conditions exist or are anticipated, unles the airplane is, or will be protected by the application of Type II or Type IV fluid".
And further on:
"In flight, the wing anti-ice system may be used as a de-icer or as an anti-icer. The primary method is to use it as a de-icer by allowing ice to accumulate before turning the wing anti-ice on. This procedure provides the cleanest airfoil surface, the least possible runback and the least thrust and fuel penalty.
The secondary method is to use wing anti-ice before ice accumulation. Operate the wing anti-ice system as an anti-icer only during extended operations in moderator or severe icing conditions, such as holding."
Source: Boeing 737 FCOM, SP 16, Adverse Weather