Primarily for general aviation discussion, but other aviation topics are also welcome.
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User avatar
By neilmurg
#1672133
and, I have nothing more to add, either, so I'm er... telling you this to be clear,


that there's nothing more to add. Please page to the bottom and press confirm.


Sorry, I'm not sorry.
User avatar
By neilmurg
#1672134
Dear Harry
I am NOT criticising you. I do value your contribution, so please don't feel insulted.
But adding a post to say you have nothing to say is genuinely funny, thanks for that.
It's more funny that I struggle with the same thing, I think it's an internet thing. All the best
User avatar
By Lockhaven
#1672136
neilmurg wrote:Dear Harry
I am NOT criticising you. I do value your contribution, so please don't feel insulted.
But adding a post to say you have nothing to say is genuinely funny, thanks for that.
It's more funny that I struggle with the same thing, I think it's an internet thing. All the best


Damm you, now I won't get the answer to my questions, how dare you. :wink:
By Harry Brown
#1672140
1.7.3
Aircraft icing
As detailed in CAA Civil Avia
tion Publication (CAP) 512: “
any deposits of
ice, snow or frost on the external surfaces of an aircraft may drastically affect
its performance. This can be due
to reduced aerodynamic lift and increased
aerodynamic drag resulting from the di
sturbed airflow over the aerofoil
surfaces, or due to the weight of th
e deposit over the whole aircraft. The
operation of an aircraft may also be se
riously affected by the freezing of
moisture in controls, hinges and micro-switc
hes, or by the ingestion of ice into
the
engine. Furthermore, since the in
-flight de-icing system may not become
effective until the aircraft is establishe
d in the climbout, the measures taken to
remove frozen deposits on the ground must
also be such as to provide adequate
protection during the initial stages of flight.


General and type specific regulations re
garding protection from contamination
are contained within national regulations
, aircraft flight manuals and company
operations manuals; relevant extracts fr
om these publications are included in
Section 1.18.5.
User avatar
By Lockhaven
#1672149
Harry Brown wrote:1.7.3
Aircraft icing
As detailed in CAA Civil Avia
tion Publication (CAP) 512: “
any deposits of
ice, snow or frost on the external surfaces of an aircraft may drastically affect
its performance. This can be due
to reduced aerodynamic lift and increased
aerodynamic drag resulting from the di
sturbed airflow over the aerofoil
surfaces, or due to the weight of th
e deposit over the whole aircraft. The
operation of an aircraft may also be se
riously affected by the freezing of
moisture in controls, hinges and micro-switc
hes, or by the ingestion of ice into
the
engine. Furthermore, since the in
-flight de-icing system may not become
effective until the aircraft is establishe
d in the climbout, the measures taken to
remove frozen deposits on the ground must
also be such as to provide adequate
protection during the initial stages of flight.


General and type specific regulations re
garding protection from contamination
are contained within national regulations
, aircraft flight manuals and company
operations manuals; relevant extracts fr
om these publications are included in
Section 1.18.5.


Ok one more time.

@Harry Brown

May I ask what part of the world you are flying / operating from and what aircraft types are you flying or have been flying commercially during the last 40 years as you previously stated ?

Genuine question.

LH
By Harry Brown
#1672177
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 .
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:


TRAINING RECOMMENDATIONS AND BACKGROUND INFORMATION FOR DE-ICING/ANTI-ICING
OF AIRCRAFT ON THE GROUND
EDITION 5, September 2008
Available at http://www.aea.be
working group consists of the following AEA member airlines:
Finnair, Chairman
SAS
Lufthansa
BMI
British Airways, Secretary

Page 48 of 74
Holdover time is obtained by[u] anti-icing fluids[/u] remaining on the aircraft surfaces. With a one-step de-icing/anti-icing operation the holdover time begins at the start of the operation and with a two-step operation at the
start of the final (anti-icing) step. Holdover time w
ill have effectively run out when frozen deposits start to
form/accumulate on treated aircraft surfaces.
By Harry Brown
#1672183
TRAINING RECOMMENDATIONS AND BACKGROUND INFORMATION FOR DE-ICING/ANTI-ICING
OF AIRCRAFT ON THE GROUND
EDITION 5, September 2008
Available at http://www.aea.be

3.1.5 Fluid behaviour on aircraft surfaces De-icing/anti-icing fluids can be misunderstood to be an equal contaminant on the wing as for example slush/sleet. Fluids have been tested and manufactured to perform in a certain way. This has been aerodynamically tested and it is evident that the fluid is sheared from the wing at takeoff leaving only a marginal film of fluid that does not constitute a notable aerodynamic effect. Different fluids are thicker than others are (Type-I vs. Type-II/III/IV) and less viscous fluid drain off easier than thicker fluid.
User avatar
By Lockhaven
#1672192
Harry Brown wrote:
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 .
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:


TRAINING RECOMMENDATIONS AND BACKGROUND INFORMATION FOR DE-ICING/ANTI-ICING
OF AIRCRAFT ON THE GROUND
EDITION 5, September 2008
Available at http://www.aea.be
working group consists of the following AEA member airlines:
Finnair, Chairman
SAS
Lufthansa
BMI
British Airways, Secretary

Page 48 of 74
Holdover time is obtained by[u] anti-icing fluids[/u] remaining on the aircraft surfaces. With a one-step de-icing/anti-icing operation the holdover time begins at the start of the operation and with a two-step operation at the
start of the final (anti-icing) step. Holdover time w
ill have effectively run out when frozen deposits start to
form/accumulate on treated aircraft surfaces.


TRAINING RECOMMENDATIONS AND BACKGROUND INFORMATION FOR DE-ICING/ANTI-ICING
OF AIRCRAFT ON THE GROUND
EDITION 5, September 2008
Available at http://www.aea.be

3.1.5 Fluid behaviour on aircraft surfaces De-icing/anti-icing fluids can be misunderstood to be an equal contaminant on the wing as for example slush/sleet. Fluids have been tested and manufactured to perform in a certain way. This has been aerodynamically tested and it is evident that the fluid is sheared from the wing at takeoff leaving only a marginal film of fluid that does not constitute a notable aerodynamic effect. Different fluids are thicker than others are (Type-I vs. Type-II/III/IV) and less viscous fluid drain off easier than thicker fluid.


@Harry Brown

Sorry but are you aware that de-icing / anti-icing documents are updated annually by each aircraft manufacture, the link you have provided http://www.aea.be in your 2008 document doesn't seem to work anymore, equally I am confused were you are going with this discussion after the information you have been provided with by various posters :scratch:
User avatar
By Flintstone
#1672200
Chris Martyr wrote:I'll take a question on gynaecology please Bob .



Getting your request in before Pete Spencer's sleep medicine wears off eh? Good move, he's a lady garden expert.

Which seems apposite here.
User avatar
By AerBabe
#1673872
Paul_Sengupta wrote:
PeteSpencer wrote:'Here's the gear knob, up for up and down for down, and don't pull it off' - there had been a recent case in the USA where a pilot had pulled the knob off with the gear up, necessitating a bit of on the hoof creative thinking.


I believe the "pulling the knob off" thing happened to Aerbabe and Aerbloke in a Seneca (?) which meant Aerbabe had to go scrambling around to find the knob in order to reattach it.


Not quite.

It snapped right off, but AerBloke still had a hold of it. Also, I was in the back, as the plan had been a photographic sortie. I tried to climb into the front to help, but failed. However, I realised that a headset plug might be the right size to fit into the vacant space. It wasn't, but it prompted A'Bloke to think to use the pointy end of a fuel tester. Or perhaps it was the other way round.

Lockhaven, kanga, Iceman and 1 others liked this
User avatar
By Iceman
#1673907
Ah, I stand corrected, it was a fuel tester in your case rather than the biro that had saved the day on the first occasion that the gear knob had come off in that aircraft.

Iceman 8)
User avatar
By Flintstone
#1673937
Iceman wrote:... on the first occasion that the gear knob had come off in that aircraft.

Iceman 8)



Those sound like the sort of words to come back and haunt someone. :D
Iceman liked this
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