Boeing question with regard to icing conditions

[loopa]

The airplane flight manual (AFM) defines icing conditions as when the outside air temperature (OAT) on the ground or total air temperature (TAT) in flight is 50 degrees F (10 degrees C) or less and any of the following exist:

Visible moisture (e.g., clouds, fog with visibility of one statute mile [1,600 meters] or less, rain, snow, sleet, or ice crystals).
Ice, snow, slush, or standing water on the ramps, taxiways, or runways.

So here's my question.

Runway = Bare and Dry (no way to ingest ice, snow, slush etc)
Visible Moisture: OVC050
OAT: 9 degrees.

Do you take off with ice protection on? AFM defines you to be in icing conditions, logically you are not.

Oh and if you depart with ice protection on, the penalty is that you dump 10 revenue PAX and their bags to meet your TLR data.

Thoughts?

[Dim]

No need for EAI on the ground if the clouds are at 5000ft. You would only require it to be on if the temp was below 10 and the vis was less than a mile.

[loopa]

No need for EAI on the ground if the clouds are at 5000ft. You would only require it to be on if the temp was below 10 and the vis was less than a mile.

Very logical point and quite practical for how this rule is applied. But the AFM doesn't state that less than 1 mile is the only derivative for turning on EAI. It states visible moisture period. Examples being cloud, fog with vis less than 1sm, etc.

Also I don't see any altitude defining whether EAI+WAI goes on or off. Simply if you are in icing conditions or not. Let's be devils advocate. Would EAI go on if clouds were at OVC001 any differently than it should OVC200 if OAT/TAT was 09? Cause now you'll be entering a discussion that is no where supported in the AFM. The only that is supported is that if your OAT is below 10 with vis moisture, you're in icing conditions. Meaning if you don't have ice protection on, you're in violation of the AFM to be going taking off...

Trust me I'm in agreement with you, but the way I read the AFM, the decision to go with out EAI puts you in violation of the AFM. Just look at how it's worded...

[True North]

The airplane flight manual (AFM) defines icing conditions as when the outside air temperature (OAT) on the ground or total air temperature (TAT) in flight is 50 degrees F (10 degrees C) or less and any of the following exist:

Visible moisture (e.g., clouds, fog with visibility of one statute mile [1,600 meters] or less, rain, snow, sleet, or ice crystals).
Ice, snow, slush, or standing water on the ramps, taxiways, or runways.

So here's my question.

Runway = Bare and Dry (no way to ingest ice, snow, slush etc)
Visible Moisture: OVC050
OAT: 9 degrees.

Do you take off with ice protection on? AFM defines you to be in icing conditions, logically you are not.

Oh and if you depart with ice protection on, the penalty is that you dump 10 revenue PAX and their bags to meet your TLR data.

Thoughts?

How do you figure the AFM definition applies to your case? There is no visible moisture.

[ahramin]

But the AFM doesn't state that less than 1 mile is the only derivative for turning on EAI. It states visible moisture period.

It doesn't mean can you SEE visible moisture, it means are you IN visible moisture. You're not in icing conditions if you are flying over Toronto and can see clouds in Buffalo.

The one mile vis is there to help you determine where the line is between a light mist that doesn't require EAI and fog which does.

Would EAI go on if clouds were at OVC001 any differently than it should OVC200 if OAT/TAT was 09?

Obviously at OVC001 EAI is on for takeoff. For OVC200 see above.

For drawing the line for takeoff performance calculations, I would use EAI on numbers if I'm going to be entering icing conditions below MFRA.

[loopa]

The airplane flight manual (AFM) defines icing conditions as when the outside air temperature (OAT) on the ground or total air temperature (TAT) in flight is 50 degrees F (10 degrees C) or less and any of the following exist:

Visible moisture (e.g., clouds, fog with visibility of one statute mile [1,600 meters] or less, rain, snow, sleet, or ice crystals).
Ice, snow, slush, or standing water on the ramps, taxiways, or runways.

So here's my question.

Runway = Bare and Dry (no way to ingest ice, snow, slush etc)
Visible Moisture: OVC050
OAT: 9 degrees.

Do you take off with ice protection on? AFM defines you to be in icing conditions, logically you are not.

Oh and if you depart with ice protection on, the penalty is that you dump 10 revenue PAX and their bags to meet your TLR data.

Thoughts?

How do you figure the AFM definition applies to your case? There is no visible moisture.

Visible moisture (e.g., clouds, fog with visibility of one statute mile [1,600 meters] or less, rain, snow, sleet, or ice crystals).

OVC 5000' would mean there are clouds present.

Ahramin you have a very valid point. But it doesn't say IN visible moisture. Just says 10 degrees OAT/TAT and Visible Moisture.

Make sure you turn on your EAI when flying over Toronto and see clouds ok? I totally get what you're saying.

Obviously at OVC001 EAI is on for takeoff. For OVC200 see above.

Not so obvious there, because OVC001 in the context of takeoff means you aren't IN visible moisture, you can only SEE it coming. Very much similar to seeing OVC050 in my original scenario.

At no point is an altitude specified for when you must be turning on your ice protection. Only conditions are specified. Is it left up to common sense then? Or would you be in violation if you had Visible Moisture (even if seen), 10 degrees or less, and took off with no ice protection on?

So where does this argument become practical? You don't want to break what the AFM says but it leaves a pretty big grey area at the same time.

Just to be clear, the discussion isn't about common sense. It's about if you had to fight your case in front of a tribunal, what evidence to you have supporting your case to takeoff without ice protection if you are below 10 degrees with visible moisture...

[FICU]

"IN" visible moisture not, visible moisture 5000 feet above.

[True North]

The airplane flight manual (AFM) defines icing conditions as when the outside air temperature (OAT) on the ground or total air temperature (TAT) in flight is 50 degrees F (10 degrees C) or less and any of the following exist:

Visible moisture (e.g., clouds, fog with visibility of one statute mile [1,600 meters] or less, rain, snow, sleet, or ice crystals).
Ice, snow, slush, or standing water on the ramps, taxiways, or runways.

So here's my question.

Runway = Bare and Dry (no way to ingest ice, snow, slush etc)
Visible Moisture: OVC050
OAT: 9 degrees.

Do you take off with ice protection on? AFM defines you to be in icing conditions, logically you are not.

Oh and if you depart with ice protection on, the penalty is that you dump 10 revenue PAX and their bags to meet your TLR data.

Thoughts?

How do you figure the AFM definition applies to your case? There is no visible moisture.

Visible moisture (e.g., clouds, fog with visibility of one statute mile [1,600 meters] or less, rain, snow, sleet, or ice crystals).

OVC 5000' would mean there are clouds present.

Ahramin you have a very valid point. But it doesn't say IN visible moisture. Just says 10 degrees OAT/TAT and Visible Moisture.

Make sure you turn on your EAI when flying over Toronto and see clouds ok? I totally get what you're saying.

Obviously at OVC001 EAI is on for takeoff. For OVC200 see above.

Not so obvious there, because OVC001 in the context of takeoff means you aren't IN visible moisture, you can only SEE it coming. Very much similar to seeing OVC050 in my original scenario.

At no point is an altitude specified for when you must be turning on your ice protection. Only conditions are specified. Is it left up to common sense then? Or would you be in violation if you had Visible Moisture (even if seen), 10 degrees or less, and took off with no ice protection on?

So where does this argument become practical? You don't want to break what the AFM says but it leaves a pretty big grey area at the same time.

The definition means you are IN visible moisture, not that you can see some 10 miles away.

If you are planning to use wing ant ice prior to 1500' AGL you must apply the penalty for takeoff. I can't remember what the altitude is for the engine anti ice penalty, probably the same.

[ahramin]

Loopa, if you are at FL250 over Toronto and see a broken cloud layer 40 miles to the South, do you think Boeing requires you to have EAI on? You have to be IN the cloud for you to be IN the icing conditions in the cloud. Similarly if you are taking off in the clear in Vancouver and the METAR shows FZFG in Calgary, you aren't in icing conditions because you aren't IN the icing conditions, despite them existing in Calgary.

Obviously at OVC001 EAI is on for takeoff. For OVC200 see above.

Not so obvious there, because OVC001 means you aren't IN visible moisture, you can only SEE it.

Maybe not so obvious to you, but should be obvious to any pilot. If there are icing conditions at 100' and you don't turn on your EAI before takeoff, when are you going to turn it on? Halfway down the runway? 20'? 80'? Takeoffs are the most critical phase of flight, you don't want to be flipping unnecessary switches during the most critical phase.

[ahramin]

"IN" visible moisture not, visible moisture 5000 feet above.

And yet we still have posters here who think proper punctuation is a fetish rather than a necessity .

[FICU]

By "exist" the AFM is referring to visible moisture being present in the immediate environment of the aircraft during any phase of flight. if clouds cigs are 100 feet you would put it on for take off because it saves workload if you left it off and had to put it on prior to entering the bases immediately after take-off. You must have it on for taxi if there is snow on the taxiway but can shut it off for take-off if the runway is bare and dry.

[ahramin]

If you are planning to use wing ant ice prior to 1500' AGL you must apply the penalty for takeoff.

Where did you find that TN?

[loopa]

Wow. Kinda scary when you think about it.

Loopa, if you are at FL250 over Toronto and see a broken cloud layer 40 miles to the South, do you think Boeing requires you to have EAI on? Shouldn't have to explain this again but you have to be IN the cloud for you to be IN the icing conditions. Similarly if you are taking off in the clear in Vancouver and the METAR shows FZFG in Calgary, you aren't in icing conditions because, you aren't IN the icing conditions, even though they exist in Calgary.

Obviously at OVC001 EAI is on for takeoff. For OVC200 see above.

Not so obvious there, because OVC001 means you aren't IN visible moisture, you can only SEE it.

Maybe not so obvious to you, but should be obvious to any pilot. If there are icing conditions at 100' and you don't turn on your EAI before takeoff, when are you going to turn it on? Halfway down the runway? 20'? 80'? Takeoffs are the most critical phase of flight, you don't want to be flipping unnecessary switches during the most critical phase do you?

I have a feeling you're assuming that you're dealing with a complete idiot. Hopefully you got the hint that i was joking when I said you MUST turn on EAI next time you're over YYZ lol

So why is it that 100 feet determines icing conditions if the OAT is +9, but 5000 feet does not when discussing the context of takeoff? They are both visible moisture, and are both in the departure environment. Yes... it's stupid to take a penalty for something that is 5000 AGL, I agree, but the AFM doesn't make the definition out to be altitude based.

Yes, your CYVR scenario makes sense. I agree 100%

True North. I hear a lot of pilot's say what you just said there about 1500', it makes a lot of sense, but isn't actually documented anywhere.

By "exist" the AFM is referring to visible moisture being present in the immediate environment of the aircraft during any phase of flight. if clouds cigs are 100 feet you would put it on for take off because it saves workload if you left it off and had to put it on prior to entering the bases immediately after take-off. You must have it on for taxi if there is snow on the taxiway but can shut it off for take-off if the runway is bare and dry.

So we are getting mixed answers... In, in the intermediate environment, 10 degrees AND visible moisture... see the grey area? So the big question of the day is what determines IN ICING conditions? 100 feet? 1000 feet? 1500 feet? 2000 feet? or my 5000 feet? ... My answer is common sense.

But that doesn't work when the guy beside me is convinced you do need EAI on in my 5000 foot scenario.

[FICU]

So why is it that 100 feet determines icing conditions if the OAT is +9, but 5000 feet does not when discussing the context of takeoff? They are both visible moisture, and are both in the departure environment. Yes... it's stupid to take a penalty for something that is 5000 AGL, I agree, but the AFM doesn't make the definition out to be altitude based.

100 feet doesn't determine anything...

Boeing says that EAI must be on while in visible moisture with OAT(on ground) or TAT(in flight) at +10 or less. Pretty simple.

[ahramin]

Where does the takeoff segment start and end?

[loopa]

So why is it that 100 feet determines icing conditions if the OAT is +9, but 5000 feet does not when discussing the context of takeoff? They are both visible moisture, and are both in the departure environment. Yes... it's stupid to take a penalty for something that is 5000 AGL, I agree, but the AFM doesn't make the definition out to be altitude based.

100 feet doesn't determine anything...

Boeing says that EAI must be on while in visible moisture with OAT(on ground) or TAT(in flight) at +10 or less. Pretty simple.

You'd think...

So then if 100 feet doesn't determine it, what does? What is "IMMEDIATE" environment? Clearly my 5000 foot scenario isn't immediate, and a 100 foot scenario is (obviously).

I think I've opened up a can of worms

Where does the takeoff segment start and end?

35 feet, to 1500 aae.

[FICU]

By "exist" the AFM is referring to visible moisture being present in the immediate environment of the aircraft during any phase of flight. if clouds cigs are 100 feet you would put it on for take off because it saves workload if you left it off and had to put it on prior to entering the bases immediately after take-off. You must have it on for taxi if there is snow on the taxiway but can shut it off for take-off if the runway is bare and dry.

So we are getting mixed answers... In, in the intermediate environment, 10 degrees AND visible moisture... see the grey area? So the big question of the day is what determines IN ICING conditions? 100 feet? 1000 feet? 1500 feet? 2000 feet? or my 5000 feet? ... My answer is common sense.

But that doesn't work when the guy beside me is convinced you do need EAI on in my 5000 foot scenario.

Oh boy... by "immediate environment" I mean what environment the jet is physically exposed to at the immediate, current, and present time you plan on operating the engines. Not 5000 feet immediately above the airport or that snow shower immediately 10nm away from the airport in the opposite direction.

[loopa]

By "exist" the AFM is referring to visible moisture being present in the immediate environment of the aircraft during any phase of flight. if clouds cigs are 100 feet you would put it on for take off because it saves workload if you left it off and had to put it on prior to entering the bases immediately after take-off. You must have it on for taxi if there is snow on the taxiway but can shut it off for take-off if the runway is bare and dry.

So we are getting mixed answers... In, in the intermediate environment, 10 degrees AND visible moisture... see the grey area? So the big question of the day is what determines IN ICING conditions? 100 feet? 1000 feet? 1500 feet? 2000 feet? or my 5000 feet? ... My answer is common sense.

But that doesn't work when the guy beside me is convinced you do need EAI on in my 5000 foot scenario.

Oh boy... by "immediate environment" I mean what environment the jet is physically exposed to at the immediate, current, and present time you plan on operating the engines. Not 5000 feet immediately above the airport or that snow shower immediately 10nm away from the airport in the opposite direction.

Hahahah, boy would I like to have a pairing with you

So, at what point would you say you wouldn't turn on EAI for Takeoff? 100' you said you would. 5000' you said you won't. What's that magic number then? How about if clouds are at 1000 OVC?

[ahramin]

Where does the takeoff segment start and end?

35 feet, to 1500 aae.

I'd include the ground segment but in any case, there's your answer.

[loopa]

So you're saying that if you encounter ICING CONDITIONS between 35 feet to 1500 feet AAE, turn on EAI and take the penalty, otherwise turn it off...

[ahramin]

Are going to encounter icing conditions ... yes.

[loopa]

Don't forget to turn on EAI when you're FL350 over YYZ and your TAT is -9 with that cloud 20 miles ahead ahramin.

So ahramin. You're an experienced guy. Is the ICING definition of 10 OAT/TAT below + vis moisture assumed from 35 feet to 1500 feet aae for the purpose of takeoff? Cause it sure isn't written anywhere.

[squash junky]

By the time you hit 150kts or Vr the thing will start screaming "engine anti ice" because of the temperature rise (ram rise).
So....keep it off.
Or are those alerts suppressed until 400'?
Whatever. To turn it on with ovc 5000' is just plain silly.

[loopa]

By the time you hit 150kts or Vr the thing will start screaming "anti ice" because of the temperature rise (ram rise).
So....keep it off.

Love it

[ahramin]

Haven't found anything in the Boeing docs yet but that doesn't mean it isn't there. I asked FICU, we'll see what comes back. I have to go play Chef Pierre right now but I'll check Airbus docs this evening.