Wing Anti-ice ON after de-icing?
Join Date: May 2003
Location: The Roman Empire
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I'm surprised nobody mentioned the two different systems installed on 737's (classics).
Are we the only ones to have the two models?
Our company has acquired a bunch of airplanes from everywhere in the last years (from Holland, Spain, British etc...) and we operate with several different layouts (some even have dual steering, or the audio control box external to the pilot seat, close to the mask - which everybody hates, including me!).
Talking about wing anti-ice, we have two models:
1) ON - OFF. Two position switch, which can be operated on the ground, and closes with TO thrust, and trips at liftoff.
With this kind of system installed, the procedure quoted by CaptSandl is the correct one.
2) GND TEST - OFF - ON. Three position switch, which works exactly the opposite way!
You cannot operate wing anti-ice on the ground, unless you hold the spring loaded switch to GND TEST momentarily.
This would only be to make a functional test.
But you can arm wing anti-ice by placing the switch to ON.
At liftoff, the valves will open.
Funny, isnt'it?
Now, you see that in the same company we operate with two totally different procedures...
And the question is: if two opposite procedures are good, according to Boeing, isn't it all this sort of BS????
And the confusion amongst our crews seems to prove this... as I'm always amazed I seem to be one of the very few guys who turn the wing anti-ice ON on the ground, with the first model described.
LEM
Are we the only ones to have the two models?
Our company has acquired a bunch of airplanes from everywhere in the last years (from Holland, Spain, British etc...) and we operate with several different layouts (some even have dual steering, or the audio control box external to the pilot seat, close to the mask - which everybody hates, including me!).
Talking about wing anti-ice, we have two models:
1) ON - OFF. Two position switch, which can be operated on the ground, and closes with TO thrust, and trips at liftoff.
With this kind of system installed, the procedure quoted by CaptSandl is the correct one.
2) GND TEST - OFF - ON. Three position switch, which works exactly the opposite way!
You cannot operate wing anti-ice on the ground, unless you hold the spring loaded switch to GND TEST momentarily.
This would only be to make a functional test.
But you can arm wing anti-ice by placing the switch to ON.
At liftoff, the valves will open.
Funny, isnt'it?
Now, you see that in the same company we operate with two totally different procedures...
And the question is: if two opposite procedures are good, according to Boeing, isn't it all this sort of BS????
And the confusion amongst our crews seems to prove this... as I'm always amazed I seem to be one of the very few guys who turn the wing anti-ice ON on the ground, with the first model described.
LEM
Join Date: Oct 2004
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Hi LEM do you also take a 3500 kg climb penalty for the old system, ie the one activated after take off. Also has anyone considered a bleeds off take off. WAI only available after you've reconfigured the air system.
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Hi ivor tug, yes of course you have to apply the penalty if at any point in the take off profile you plan to use wing and/or engine anti-ice.
Btw, I don't think anybody will ever arm wing anti-ice before takeoff, as we know the 737 doesn't have any problem, except under extreme icing conditions, maybe.
Btw, I don't think anybody will ever arm wing anti-ice before takeoff, as we know the 737 doesn't have any problem, except under extreme icing conditions, maybe.
