de-anti icing
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de-anti icing
In the winter...we found frost on the wing...... we make full wing fuel so the frost will melt.....what do you think about doing the de/anti icng procedures in sub-zero condition?
I was thinking that the frost melting is still on the wing (water) and con be re-freeze.... what do you think?
I was thinking that the frost melting is still on the wing (water) and con be re-freeze.... what do you think?
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NO frost on the upper wing surface is allowed by US FAA rules! Only 1/8" on the lower surface under the fuel tanks is allowed.
If there is frost on preflight, get it de-iced.
If there is frost on preflight, get it de-iced.
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If there are frost, snow or ice deposits on the upper wing surface, you must de-ice before take-off, and take notice of Holdover Times according to the level of snow falling or blowing in the wind. You are allowed up to 3 mm of frost under the wing where the fuel tanks are. In addition, the aeroplane can have thin Hoar Frost over the fuselage as long as writing and surface detail can be seen underneath. This is the same as the frost that forms on cars overnight.
It is quite valid to put warm fuel into the wing tanks to melt the ice on the upper wing surface. It will remain wet, but it will not refreeze on the ground for a long time. Once you get airborne, it doesn't matter- you will quickly get up to high speed- remember you can take off into supercooled rain. All that matters is getting airborne and the first minute or so of flight. As long as when you start your take-off roll, you have no ice or snow deposits on the upper surface of the wing.
It is quite valid to put warm fuel into the wing tanks to melt the ice on the upper wing surface. It will remain wet, but it will not refreeze on the ground for a long time. Once you get airborne, it doesn't matter- you will quickly get up to high speed- remember you can take off into supercooled rain. All that matters is getting airborne and the first minute or so of flight. As long as when you start your take-off roll, you have no ice or snow deposits on the upper surface of the wing.
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Just to correct 'not-so' and 'intruder' - Boeing have 'approved' upper-wing frost caused by cold fuel on their newer thin wings, as long as the 'frost' is within the marked area and the whole thing is approved by the regulatory authority.
BTW I don't think the UK has agreed to it - so there, you Limeys.
Better talk to your 'Tony' about it.
BTW I don't think the UK has agreed to it - so there, you Limeys.
Better talk to your 'Tony' about it.
For European / all operators see AEA Icing Recommendations and Training
and
refer to JAR-OPS 1.345, particularly AMJ 1.345
For those less well informed US contributors, see NTSB Safety Alert - Aircraft Ground Icing
and
refer to JAR-OPS 1.345, particularly AMJ 1.345
For those less well informed US contributors, see NTSB Safety Alert - Aircraft Ground Icing
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Boeing have 'approved' upper-wing frost caused by cold fuel on their newer thin wings, as long as the 'frost' is within the marked area and the whole thing is approved by the regulatory authority.
BTW, which are the "newer thin wings" to which this applies? Do you have the Boeing document or doc number?
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From Boeing 'Cold Soak' publication, May 2004
Boeing will incorporate CSFF permissable area in production starting with line number 1538 in July 2004, as a standard feature
- Lines on wing upper surface
- Manual updates to support operations will include Airplane Flight Manual, Airplane Maintenance Manual, and Flight Crew Operations Manual
Retrofit will be available as per Boeing Service Bulletin 737-11-1125
If you ain't got it, ask about it. I don't know how far it has got with 'approval', but the tests have been done and it is ok - and we need it!
Boeing will incorporate CSFF permissable area in production starting with line number 1538 in July 2004, as a standard feature
- Lines on wing upper surface
- Manual updates to support operations will include Airplane Flight Manual, Airplane Maintenance Manual, and Flight Crew Operations Manual
Retrofit will be available as per Boeing Service Bulletin 737-11-1125
If you ain't got it, ask about it. I don't know how far it has got with 'approval', but the tests have been done and it is ok - and we need it!
Well we have a regulation in the operation section and now we have a manufacturer claiming that maybe it shouldn't apply to their Type certificate product, what with tests and all.
I really don't believe that things like this are that easily accomodated. A petition needs to be made for exemption, against the rule and such petition needs to be examined by the public interests (published in the Federal Register) for all coments for and against.
So who actually is filing such a petition, Boeing or the operators?
I shall be glad to place in the record my opinions on the matter after I see the petition.
I really don't believe that things like this are that easily accomodated. A petition needs to be made for exemption, against the rule and such petition needs to be examined by the public interests (published in the Federal Register) for all coments for and against.
So who actually is filing such a petition, Boeing or the operators?
I shall be glad to place in the record my opinions on the matter after I see the petition.
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We operate B-737NG:s in JAA environement.
We operate with frost on the top of the wings however only inside the markings on the wing and only in temperaures above 0C to prevent runback icing and also no precipitation is alowed.
Hope this answers your question.
We operate with frost on the top of the wings however only inside the markings on the wing and only in temperaures above 0C to prevent runback icing and also no precipitation is alowed.
Hope this answers your question.
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Here we go again. Get rid of it all. De-ice it, have the damn thing dripping with fluid immediately before departure. If you are the captain, and you are lined up for takeoff, and you are not 100% sure that your aircraft is clean, you must NOT depart. I'm talking generically, non-type specific, but please guys, don't mess with ice, GET RID OF IT. If you can't, then DON'T GO!! I know that some types are allowed to depart with a thin layer of frost on the underside of the wings within certain areas, fair enough, but for heaven's sake, if there is ice on your airframe and/or control surfaces then for all you know you are getting airborne in the aerodynamic equivalent of one of Fred Dibnah's steam rollers and you will die. Please, don't do it.
Last edited by Smudger; 24th Feb 2007 at 21:16.
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if there is ice on your airframe and/or control surfaces then for all you know you are getting airborne in the aerodynamic equivalent of one of Fred Dibnah's steam rollers
If you are the captain, and you are lined up for takeoff, and you are not 100% sure that your aircraft is clean, you must NOT depart.
For those unfamiliar with Fred Dibnah; he was the archetype ‘back yard mechanic’ (with university degrees in the subject). There are many good lessons to be taken from his biography; as a steeple-jack ‘one false step and you are saying hello to St Peter’. Another, ‘of all the accidents I had, they occurred when I was distracted’.
In aviation, there are three types of ice.
Good Ice, Bad Ice and Hazardous Ice.
Good Ice is found in the galley.
One of the objectives of flight is to keep the aircraft from shaking.
If it shakes, it is either too fast or too slow.
Or covered in ICE !
annon
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Chaps, here we have the classic pprune 'x' answers and 'x+1' different opinions! I tried to condense in reply #3 what my flying manual said for the 747 and 737. Thin frost on the fuselage is allowed. I know nothing about allowing frost on the upper wing surface. I guess everyone is right in their own way, but the only 'right' answer for <it.pilot737> is what's written in his flying manual, and a healthy dose of respect for the problem.
So many aeroplanes have piled in because of ice, and still do, that I find it strange how the rules change and if frost is now allowed on the upper wing surface. But I always believe in asking the people who know. What we need is a combined rule setting meeting of Air Canada, Air Alaska, SAS and Aeroflot to set the guidelines, and keep the politicians and office flyers out of it!
So many aeroplanes have piled in because of ice, and still do, that I find it strange how the rules change and if frost is now allowed on the upper wing surface. But I always believe in asking the people who know. What we need is a combined rule setting meeting of Air Canada, Air Alaska, SAS and Aeroflot to set the guidelines, and keep the politicians and office flyers out of it!
Back in '89 I was SLF in a Wardair A310 out of YYC on a fine day. Taxiing out I noticed frost over the wing tanks from cold soaked fuel and considered if I should make a fuss, but in relation to the total wing area and being well back from the leading edge, I decided it was acceptable.
Back at YYZ, I sent a note to ops and received a reply from the CP that the A310 certification allowed frost over the wing tank.
After the Dryden report came out, I believe Transport Canada made regs requiring an absolutely clean upper surface irrespective of manufacturer data.
If the manufacturer has done the test flights with frost over the tanks (as well as under) and has properly accounted for an engine failure, a thin frost over the tanks can be acceptable in operation.
Back at YYZ, I sent a note to ops and received a reply from the CP that the A310 certification allowed frost over the wing tank.
After the Dryden report came out, I believe Transport Canada made regs requiring an absolutely clean upper surface irrespective of manufacturer data.
If the manufacturer has done the test flights with frost over the tanks (as well as under) and has properly accounted for an engine failure, a thin frost over the tanks can be acceptable in operation.
Per Ardua ad Astraeus
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Been following this with some interest and I see the Boeing 737-800 FCOM allows it subject to 'regulatory approval', so your airline Ops Manual should say yeay or nay.
- I'm not sure, but I suspect there was more than a small amount of thin frost in an approved area of the wings on most of the 'departed'? The 'no ice' rule is possibly just a (sensible) blanket restriction which can now be reviewed after satisfactory investigation/testing? Things do move on, and sometimes for the better.
The Boeing 'limitations' on it are quite specific.
So many aeroplanes have piled in because of ice, and still do, that I find it strange how the rules change and if frost is now allowed on the upper wing surface.
The Boeing 'limitations' on it are quite specific.
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In the real world keep it simple…
For simple pilots and de-icers. Yes they are in the real world! Frost on the uppers is a no go, no matter what the thickness or area it is in. I am sure many of you like myself have seen Ice/frost spread like cancer across the wing after inspecting aircraft on arrival, and just before departure. The fresh/warmer fuel temp did not melt it that time!
A lot depends on the temp (of course), the wind direction, parking location, and the way the apu hot air is blowing - is another e.g.
Many a time the crew do not look at the wings from the steps or windows with this in mind. What about that one time the aircraft is delayed that little bit longer, and they go with the attitude of - nah we will be ok? and it aint!
Boeing says they allow it in some in areas…blah…blah!
off ! You get on the wing and measure it with a ruler matey! You can do a tactile test for most of the wing (without risking some damage with a basket, etc). Always cop a feel if you have any doubts. Shinny metal can look ok. But it could be covered in a thin layer of ice.
If in doubt de-ice it!
Procedures - Airlines all have their own. You would need a book the size of War and Peace on you for reference going airside.
Again keep it simple and the same rule for all types of aircraft.
For simple pilots and de-icers. Yes they are in the real world! Frost on the uppers is a no go, no matter what the thickness or area it is in. I am sure many of you like myself have seen Ice/frost spread like cancer across the wing after inspecting aircraft on arrival, and just before departure. The fresh/warmer fuel temp did not melt it that time!
A lot depends on the temp (of course), the wind direction, parking location, and the way the apu hot air is blowing - is another e.g.
Many a time the crew do not look at the wings from the steps or windows with this in mind. What about that one time the aircraft is delayed that little bit longer, and they go with the attitude of - nah we will be ok? and it aint!
Boeing says they allow it in some in areas…blah…blah!
off ! You get on the wing and measure it with a ruler matey! You can do a tactile test for most of the wing (without risking some damage with a basket, etc). Always cop a feel if you have any doubts. Shinny metal can look ok. But it could be covered in a thin layer of ice.If in doubt de-ice it!
Procedures - Airlines all have their own. You would need a book the size of War and Peace on you for reference going airside.
Again keep it simple and the same rule for all types of aircraft.
Completely agree airvanman.
It's bad enough already when you get some airline station managers (and pilots) insisting that "it's only a bit of ice and it's only on one side....blah blah...it'll delay us...blah blah...but de-icing will screw our bonus this month...."
If they get wind of a get out claus that may apply under certain conditions they'll be leaning on the certifyer to pen it off all the bl00dy time.
At little knowledge is dangerous!
(I should know
)
Get it de-iced.
It's bad enough already when you get some airline station managers (and pilots) insisting that "it's only a bit of ice and it's only on one side....blah blah...it'll delay us...blah blah...but de-icing will screw our bonus this month...."
If they get wind of a get out claus that may apply under certain conditions they'll be leaning on the certifyer to pen it off all the bl00dy time.
At little knowledge is dangerous!
(I should know
)Get it de-iced.
That Boeing language is a can of worms, IMHO. I wonder what it would be like to be a Captain for a company that has received approval to fly their NGs with frost on the designated areas of the wing upper surface. What do you do when a "knowledgeable" passenger makes a fuss in the cabin because they know the rule which says that the wing has to be clean? I think I'll stick to my Airbus and the clean wing concept.
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Not so good...
Gentlemen (and Ladies, as applicable),
In my humble opinion ( ), it's not a good idea to takeoff without a completely clean wing. My company's SOP is, very succinctly stated, "Make It Clean; Keep It Clean". There are too many pitfalls if you opt otherwise.
For example, years ago, an airplane crashed on takeoff due to icing on the wings. It was a cold, cold morning, and light snow had fallen during the night. When the crew arrived at the aircraft, the flight engineer (Yes, it was a long time ago! ) actually got a ladder and, with his hand, was able to brush the very dry snow off a section of the wing. It easily blew off into a fine powder. No problem...they all concluded it was safe to takeoff without being sprayed.
But, right after the snow-brushing analysis, they got their fuel. And, the fuel came from an underground tank...which, yes, you guessed it...was at a temperature well above freezing.
So, now, the warm fuel went into the wings, apparently partially melted the snow...which refroze...and, well, the rest is history.
A good, reliable rule to live by is to make it clean and keep it clean. That's the only sure way to know you're safe for takeoff. How you accomplish this is by following your company's SOPs. And, when in doubt, "DON'T" (is a good rule, too).
I've never had an engineer mind doing a tactile inspection of the wing to ensure the de-anti-icing fluid was still working. Yes, it's cold, snowing, etc., and the work conditions for these engineers are miserable. But, the consequences are simply too grave to do otherwise.
PantLoad
In my humble opinion (
), it's not a good idea to takeoff without a completely clean wing. My company's SOP is, very succinctly stated, "Make It Clean; Keep It Clean". There are too many pitfalls if you opt otherwise.For example, years ago, an airplane crashed on takeoff due to icing on the wings. It was a cold, cold morning, and light snow had fallen during the night. When the crew arrived at the aircraft, the flight engineer (Yes, it was a long time ago!
) actually got a ladder and, with his hand, was able to brush the very dry snow off a section of the wing. It easily blew off into a fine powder. No problem...they all concluded it was safe to takeoff without being sprayed.But, right after the snow-brushing analysis, they got their fuel. And, the fuel came from an underground tank...which, yes, you guessed it...was at a temperature well above freezing.
So, now, the warm fuel went into the wings, apparently partially melted the snow...which refroze...and, well, the rest is history.
A good, reliable rule to live by is to make it clean and keep it clean. That's the only sure way to know you're safe for takeoff. How you accomplish this is by following your company's SOPs. And, when in doubt, "DON'T" (is a good rule, too).
I've never had an engineer mind doing a tactile inspection of the wing to ensure the de-anti-icing fluid was still working. Yes, it's cold, snowing, etc., and the work conditions for these engineers are miserable. But, the consequences are simply too grave to do otherwise.
PantLoad