Primarily for general aviation discussion, but other aviation topics are also welcome.
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User avatar
By Lockhaven
#1672088
Just so its clear for other readers, an aircraft TKS fluid system is an anti-icing system not a de-icing system and must used prior to entering known icing conditions.

De-icing an aircraft on the ground prior to flight is using different fluids.
User avatar
By Lockhaven
#1672094
Harry Brown wrote:You still cant reply without making a snide comment can you? Your the reason that people don't use forums.

I understand what you say is fact and what I say is opinion but if this forum is now limited to only facts I can forsee a problem, can you?

Your link says
De/anti-icing fluids are designed to flow or shear off during the take-off roll so that your wing and other critical surfaces are clean for takeoff. For some aircraft, when a thickened Type II, III or IV fluid is applied, an increase in takeoff speeds (V1 & Vr) is required to ensure that the fluid shears off. Recompute your takeoff or balanced field length, if this is the case.

In active ground icing conditions, you will likely want to (or be required to) use aircraft ice protection systems during taxi and takeoff. Ice protection systems that use engine bleed air may require a reduced takeoff thrust setting and/or simply result in less thrust available. Adjust your takeoff calculations, if applicable.


I said Harry Brown wrote:
Can you tell me where these references are you are quoting that say you should not rotate with anti ice fluid on the wings.

Nowhere in that link quoted above does it say you should not rotate with anti icing fluid on the wings


By virtue of the design of de-icing fluids Type II, III and VI they will shear from the wing at a given speed so that you do not take-off with a load sticky fluid still attached.

They are designed for one thing only, that is to get you from your de-icing/parking point on the airfield to lift off within the hold over time limits of the fluid depending upon the mixture strength and the active icing conditions prevailing at the time.

Once you are airborne they have no further use for your flight, thats were the aircrafts own ice protection systems take over, however when you land even after a 6-7 hour flight there will still be a horrible thin film of residue attached to the airframe, this should ideally be washed off fairly timely as excessive residue trapped in control surface areas can rehydrate and freeze at a later date.
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By Lockhaven
#1672098
Lockhaven wrote:
Harry Brown wrote:Fuselages do not need to be deiced although unbelievably one morning a new deicing crew deiced our fuselage instead of the wings!


That statement is not completely true some types do require the fuselage de-icing.


My answer to your statement above is because aircraft fuselages most certainly do have to be de-iced / anti-iced before departure when the aircraft has a third tail mounted engine to avoid ice ingestion from ice coming off the top of the fuselage.

I.e. Falcons, 727, L1011 etc.
By Harry Brown
#1672100
Its simple really but forgive me for having an opinion after 40 years of professional flying.

You should never use a fluid on your aircraft that hasnt been approved by the aircraft manufacturer (including how it is applied) especially if you do not want to invalidate your insurance.
You should use the appropriate approved fluid to remove all the ice and precipitation.
You should use a deicer with an anti ice to give a holdover time and that time depends on type of precipitation and temperature.
The anti ice will give protection until rotate so holdover time is from application to rotate.
You will ideally rotate with an excess of fluid on the wings which will be aerodynamically removed leaving a residue.
Aircraft deicing isnt an exact process using a contents gauge, its an eyball process controlled by an operative who has undergone training.
Because of this I and all of my colleagues have always been advised to increase rotate speeds by 10 kts after deicing. I also rotate momentarily to 10 degrees rather that 15 degrees.

Millions of aircraft are deiced every year and I do not know of one loss of control accident ever due to excess fluid being applied, if you do let me know.

On the other hand there have been numerous accidents due to not deicing.

From the large aircraft ive flown from the F27 to the A321 ive never had a fuselage deiced ever so I know of no aircraft thats flight manual calls for a fuselage to be deiced and when you consider it can cost £5000 to deice a large transport aircraft you may reason why.

If you know of an any aircraft that needs to have its fuselage deiced please show me that part of the manual that says that because Flinstone only believes facts
By Harry Brown
#1672101
Lockhaven wrote:
Lockhaven wrote:
Harry Brown wrote:Fuselages do not need to be deiced although unbelievably one morning a new deicing crew deiced our fuselage instead of the wings!


That statement is not completely true some types do require the fuselage de-icing.


My answer to your statement above is because aircraft fuselages most certainly do have to be de-iced / anti-iced before departure when the aircraft has a third tail mounted engine to avoid ice ingestion from ice coming off the top of the fuselage.

I.e. Falcons, 727, L1011 etc.


Good point I can understand that
User avatar
By Flintstone
#1672112
I'm sorry but I just can't ignore this one. To back up m'learned friend lockhaven...

Harry Brown wrote:If you know of an any aircraft that needs to have its fuselage deiced please show me that part of the manual that says that because Flinstone only believes facts


Application of fluids should follow the sequence below:
- Horizontal stabilizer
- Vertical stabilizer
- Top of fuselage
- Sides of fuselage
- Wings


From here:

http://willyherren.com/sop/2010_ColdWea ... series.pdf

And Harry, how about dropping the straw man arguments? Nobody has claimed that aircraft crash due to having anti-ice fluid on the wings. Only you suggested that someone had. If they have then please provide a quote.

The topic of conversation here started with your assertion that "You do ideally want to get airborne with glycol covered wings" which has been shown not to be the case.

It then moved to your assertion that fuselages need do not need to be cleared (some do, see above).

I'm more than happy to discuss and learn but even in the face of evidence that contradicts your assertions you continue to cut and paste large tracts of irrelevant texts. That's not discussing.
Last edited by Flintstone on Tue Feb 05, 2019 8:14 pm, edited 1 time in total.
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By Chris Martyr
#1672113
Harry : Anti-icing is what is carried out on an aircraft that is going to be parked up overnight in lowering temp. conditions . It is to stop the build up of ice/frost on the surfaces and uses a very strong solution of fluid .
De-icing is what is carried out just prior to the a/c's departure . It is normally a hot solution of water/fluid and hold-over times vary according to where you are in the world and whether it is snowing / how cold it is and the type/ratio of the solution,,,,etc,,,etc,,,. There is no 'one stop shop' answer to any of this .

Once de-iced and on the t/o roll , the theory is that by the time the aeroplane is on the move , the de-icing fluid and all the other smeg will lift from the surfaces and the aircraft can rotate [theoretically] with clean wings .

The real contamination problem lies with what gets into all the nooks & crannies . That's an engineer problem , not a pilot one . [hopefully]

I've been overseeing de-icing on aeroplanes for a long , long time . And signing for it .
In the same way as Flintstone has probably been rotating into clag with de-iced wings/empennage all signed off by some grubby , grumpy engineer.

So , steady as y' go mate... :wink:
By Harry Brown
#1672117
Chris Martyr wrote:Harry : Anti-icing is what is carried out on an aircraft that is going to be parked up overnight in lowering temp. conditions . It is to stop the build up of ice/frost on the surfaces and uses a very strong solution of fluid .
So , steady as y' go mate... :wink:


Really, wow! So the all the Kilfrost our airline has been buying over the last 50 years plus was a waste of money then?
User avatar
By neilmurg
#1672123
priceless..
....please kiss and make up
--or--

This thread is 'De ice LIGHT aircraft!
I'm outraged that you should drag CAT into this, you've insulted my mother and my entire value system!
--or--

have at it guys, slow Tuesday here in Surrey and there's nothing on the tele

[edit]Tea, Earl Grey, Hot?[/edit] [edit2]also a superb de-icer[/edit2]
Last edited by neilmurg on Tue Feb 05, 2019 8:36 pm, edited 2 times in total.
mick w, Lockhaven liked this
User avatar
By Lockhaven
#1672127
Harry Brown wrote:Its simple really but forgive me for having an opinion after 40 years of professional flying.

Because of this I and all of my colleagues have always been advised to increase rotate speeds by 10 kts after deicing. I also rotate momentarily to 10 degrees rather that 15 degrees.

If you know of an any aircraft that needs to have its fuselage deiced please show me that part of the manual that says that because Flinstone only believes facts


Who has advised you and your colleagues to rotate 10kts faster after de-icing, is the aircraft manufacture for the aircraft you fly offering this information in the contaminated runway performance section of your AFM, is this correction adjusted for different aircraft weights, if not how are you recalculating the runway field lengths ?

I gave you examples that 3 engine aircraft with fuselage top mounted engines require the fuselage to be de-iced to avoid ice ingestion of that engine, many two engine types with engines mounted on the rear fuselage also require the fuselage sides to be de-iced for the same reason to avoid ice ingestion.
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