Type I Fluid Foaming?

[Four1oh]

I've 'heard' of it, but has anyone here ever experienced it? Basically, it can happen during a Type I fluid application, and might look like slush on the wing after a deice application(you might think you were improperly deiced). If it did happen to you what did it look like, and how long did it last before dissipating? Also, did the fluid foam constantly from the same truck, for the entire deice on both wings(uniform), or was it 'spotty'.

I've asked a few guys I know, and they've never seen or even heard of this phenomenon. In my 17 years as a pilot, and all the training about icing/deicing and winter experience I've amassed, this is the first I've heard of it.

Just thought I'd throw this out 'there', thanks.

[wtf_over]

Don't tell Doc you doing surface contamination training

[quote]then you are a total moron![quote]

This is what his response is concerning any training on this topic. Now to be fair he does know it all so you should too.

and my answer is no I haven't heard of it.

Maybe doc can fill us in

[Grey_Wolf]

http://www.tc.gc.ca/CivilAviation/comme ... 2/menu.htm
http://www.tc.gc.ca/civilaviation/gener ... 3/Menu.htm
http://aircrafticing.grc.nasa.gov/courses.html



Education .....

"I am beginning to suspect all elaborate and special systems of education. They seem to me to be built up on the supposition that every child is a kind of idiot who must be taught to think." -- Anne Sullivan

Don't tell Doc you doing surface contamination training

then you are a total moron!

This is what his response is concerning any training on this topic. Now to be fair he does know it all so you should too.
and my answer is no I haven't heard of it.
Maybe doc can fill us in

[Four1oh]

This has nothing to do with de-ice training, it has to do with getting to the bottom of an explanation I was given for what I thought was improper deicing procedures resulting in what very clearly(to me) looked like residual slush on the wing. I want experiences/opinions, not links, thanks.

[mulligan]

I have seen foaming on a number of ocaccions but not for quite a while now. I started in 1976 so I'm thinking it was something to do with the older fluids (type 1 was the only type then) and that modern formulations aren't prone to it. As I remember it was fairly easy to identify especially at night with the wing lights on, bearing in mind that you could only see part of the wing and had to make an asumption about the rest. It was usually scattered about in small patches and might have covered about 10% of the wing surface in total.
It didn't look like slush. Hmmm...more like soap suds I'd say.
We never waited for it to dissipate. It was "just a little foaming" and familiar to us.
When it did happen it was generally equally present on both wings.
If you've been at it for 17 years then I'd guess the "problem" has been eliminated.
Hope this helps.

[Rockie]

One thing I've never seen anywhere at any company or from TC are actual photographs showing what de-ice fluid looks like when it loses its effectiveness or is foaming. It is such a simple thing and would be worth more than any number of manuals trying to describe it. Has anyone here seen anything like it? If so, where?

Edit

Just found something. The NASA de-ice training found on the link above has a few pictures that are poor quality but better than nothing. They can be found in section V, holdover time factors and go no-go decision. It is a slide show and you can navigate directly to the pages.

[invertedattitude]

This has nothing to do with de-ice training, it has to do with getting to the bottom of an explanation I was given for what I thought was improper deicing procedures resulting in what very clearly(to me) looked like residual slush on the wing. I want experiences/opinions, not links, thanks.

410,

The only time I've seen the situation you speak of is when TYPE I was applied to packed snowfall. As you know any amount of snow on the wing acts like a sponge for de-ice fluid, and you have to more "blast" it off than just soak it.

The problem is sometimes when you're spraying heavy snow from wing-tip to root, a lot of it accumulates near the fuselage, and from the bucket it looks just like a bit of foam mixed with the fluid if you don't wait a few moments to make sure it slides off.

If you're sprayed with TYPE I, and you can see anything but an orange film over the wing, I'd definately be asking to be sprayed again, because IMO you weren't cleaned off properly.

Either the fluid failed, or perhaps they were using an incorrect mixture of water/glycol for the temperature. (Manycompanies don't mix on their own anymore because it's simply a liability waiting to happen and leave it straight as it comes from DOW or whoever)

I'd be curious to hear exactly the circumstances and what the Iceman/snowman was telling you.

[Four1oh]

I have my theories, but I don't suspect it was foaming, to say the least.

[Beech99]

The foaming happens when there is too much snow on the wing and it starts to dilute the deice fliud. The problem with that is it will start to freeze .

[mulligan]

Ok, but I've seen foam when there was no snow. It was usually right after spraying finished and there would be "flecks" of it here and there, like you would see from a clothes washer. Harmless stuff and maybe the explanation was as simple as too much hose pressure or a small obstruction in the nozzle.

[Four1oh]

ok, so a wing 80% covered with what looks dangerously like slush wasn't in the works then?

[Doc]

It's just mixing with the snow already on the wing. Pretty common when it mixes with snow. Sometimes it'll change the freeze point of the fluid. Anytime you mix two liquids, it reduces the freeze point of both. Don't know how that theory works with beer and scotch, but as long as it isn't freezing, you're good to go. Good idea to "blast" the "slush" or "foam" off the wing. The foam will shear.
It kind of looks like a watery strawberry slushy. But it tastes awful!


Oh, and wtf_over....have you been told today?

[Four1oh]

well, Doc,all I'm saying is what I saw didn't mix with the whole 'clean concept' as it's drilled into all of us. I just don't buy the reason I was given, I'm from a cold climate, and I can safely say I'm intimate as to what slush looks like, and I had the front row seat for the show.

Thanks for the info, people, it just confirms what I already thought.

[Four1oh]

The foaming happens when there is too much snow on the wing and it starts to dilute the deice fliud. The problem with that is it will start to freeze .

that sounds like fluid failure to me, and that wasn't the issue. if the fluid starts to freeze, then it's diluted to the point where it fails. This wasn't the case. In this case the contaminant wasn't removed(in my and my entire crew's opinion) by the type I fluid. Meaning the Type I fluid wasn't doing it's job, because it couldn't do it's job. Now how could it be that perfectly good Type I fluid might not be able to do it's job on the first application?

I have drawn my own conclusion, but I'd like to see someone else's answer...

[Doc]

Just a thought, but your fluid might not have been quite hot enough. What was the OAT?
Cold fluid will just make slush. Any way you could have got a cold shot?

[Four1oh]

BINGO! Of course, how does a pilot prove it?

[Doc]

You have to ask the guy applying the fluid. They have gages. Don't know the optimum temp of type 1 fluid off the cuff, but anybody running an applicator will know.

[Four1oh]

and what happens when the deicer bullshits you? then what?

[Doc]

I don't think he would bull shit ya. There's too much at stake. No sweat off his ass if he has to wait for it to get warm enough. Hell, go for a coffee. If it happened to you, you could touch base with his company and just ask what temps they deliver fluids at. Don't go on the attack, just inquire. Then mention maybe they should check their equipment? Bottom line is, it's up to you to be satisfied it's safe to go. Can't get proper deice, and you need it, check into the hotel and cancel the trip. That'll get things moving in the right direction. Put the ball in your operations mngr's court. That's why they pay him the big bucks.

[mulligan]

"ok, so a wing 80% covered with what looks dangerously like slush wasn't in the works then?"

No. What I used to see was never on more than 10-20% of the wing. To use more detail: flecks of foam scattered at random over the wing. Each one maybe 2-3 sq. inches and an inch high. If it was 80% than forget about what I've been saying.
Still makes me wonder abour hose pressure though.

[invertedattitude]

410, I said it already but I'd be willing to bet one of two things:

A.) The fluid was mixed by the de-ice company on the ground, and an improper mixture of water/glycol was used, and the fluid was beginning to fail, or possibly TYPE I that wasn't heated to the proper temperature prior to being sprayed
or
B.)Whatever contaminant was on the wing wasn't properly removed from the wing, mixed and absorbed the glycol giving you the slushy appearence (seen it a hundred times) but needs to be properly cleared

As I said before a properly de-iced wing will have only a very thin orange film over the wing surface, which should give a "stained" appearance... as in you see the wing clearly with a thin clear orange film over the wing.

Anything else and the bucket operator should have kept spraying until clear, and if it kept happening, cease de-icing operations and inform you. It wouldn't be the first time frozen contaminant that glycol failed to remove jammed a set of flaps.

Could you answer some questions to help paint the picture a bit better?
What exactly was the contaminant prior to be sprayed? What was the OAT? Was there active precip falling during de-icing?

[Doc]

Fluid was not hot enough. End of story.

[invertedattitude]

The problem with a lot of older de-ice trucks is where the temperature gauge is located, and if the bucket operator purges the line prior to spraying.

1.Most trucks the procedure is something along the lines of:

2.fire up the burners, these usually take 5-15 minutes or so to get up to temperature.

3.Turn on the pump, and starting cycling the fluid, which runs the fluid around the pump in and out of the glycol tank, which then eventually moves the colder fluid at the top and around the pump and heats it up... the temperature gauge is almost always located on or near the pump itself, thus it takes the longest to warm up and once it is at "temp" (140-180F) you should have good heated fluid.

HOWEVER many trucks also hold a good 20-30 litres in the hose lines after the pump, this is not cycled through during the pre-heating process... thus the normal procedure is the "purge" the line, as in spray onto the de-ice pad until you get hot fluid coming out, again usually 20-30 litres, this only has to be done if its the first spray in quite some time, or a new load of glycol.

Considering that on a 737NG wing depending on the contamination you would normally spray 30-100 litres for light contamination, or even on frost you would only spray sometimes barely 30 litres to remove a frost. BUT if the fluid wasn't purged from the line and went on the wing cold, there's a very good chance it could have foamed/ and or failed quickly upon contact, even though the temperature on the truck was within acceptable limits.

*Excuse the edits, I can't seem to type today

[invertedattitude]

Fluid was not hot enough. End of story.

Understanding the possible "Why's?" can only help Doc, just giving a blanket statement doesn't help anyone learn from it:


"The plane crashed, end of story"

[Doc]

What's with you guys? I never said "don't fix it." I just said it wasn't hot enough. From the cockpit you have no control over the deice bucket. Ya sees what ya sees. In this case ya sees cold deice. Is all. The question was, why the foaming....not how to fix it. Answer. It wasn't hot enough. Most of us are not involved in "firing up the burners", therefore from a pilot's stand point, the thing that really matters here, is to recognize that there is a problem, and what that problem is.
Another reason I think the 50 question exam is total BS. Nobody recognized the fact that the ice fluid, in this case was cold, and you all wrote your much beloved exam.