What not to do with TKS...

denverpilot

denverpilot

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Photo floating around some other sites at the moment. Worthy of a thread here...

40f1531d95569aa855a0966770a52669.jpg


That’s a FIKI TKS SR-22T.

Hmmm. How does that happen? And what’s going on?

(I know from reading it elsewhere but I’ll let y’all discuss first.)
 
Isn't TKS an ice prevention system, not an ice removal system ?
Waited too long before turning it on?
 
Last edited:
Took off with contaminated wings and decided to run the TKS to get the rest of the snow off?
 
Ok, I know one limitation would be the OAT - below -76F, the system won't work because the glycol/water mix will freeze. I think that's what we're seeing here.

What's the second limitation? Operating outside the mix envelope?

I know nothing about ice beyond it's bad to fly with, but it's good to learn.
 
GRG55 said:
Isn't TKS an ice prevention system, not an ice removal system ?
Waited too long before turning it on?
Click to expand...

TKS actually can be anti-ice as well as ice removal. At least according to google, definitely not according to my experience.
 
Some on the right track, others way out to lunch. :)

Two aircraft systems limitations being broken in the photo. Both related.

Wings weren’t contaminated prior.

Not water in TKS System, but kinda close.

@bflynn hit it... temperature limits.

So here’s the deal according to a pile of Cirrus instructors:

Aircraft is at FL240 at -43C. Both the TKS and *airframe* operating limits are being exceeded.

Hmmm... buy a nice turbocharged airplane and in the winter you can outclimb your airframe temperature limits!

The TKS “juice” tends to “froth” at that temp and altitude and it “no workie”. People have seen it do it warmer depending on pressure and age of fluid.

In fact, it makes the mess seen.

So, other speculation is that someone left the fluid in the tanks all summer and didn’t drain and refill.

Scenario was a fairly inexperienced instructor took the photo and posted it somewhere not realizing he was playing with very bad things there. Just turn it on and go fly in the Flight levels, right?

Not much time in weather or ice, and a bunch of Cirrus instructors kinda jumped his butt. (Unfortunately I missed that part of the show...)

Someone kept the photo (nothing ever dies on the Internet right?) and reposted it for a learning tool.

Sooooo... review those systems and know their limitations!

(And no, I haven’t flown one and didn’t know the limitations myself, just thought it was a fascinating photo. That much of a mess on the wings at FL240 where the wing performance isn’t going to be all that stellar... exceeding the airframe limitation for cold... lots of nope nope nope there...)
 
If fuel tanks can get water in them from condensation I don't see why TKS tanks can't. If TKS is water soluble, which I assume it is, then as the condensation/water enters the tank it can raise the freezing point. Just my theory.
 
denverpilot said:
(And no, I haven’t flown one and didn’t know the limitations myself, just thought it was a fascinating photo. That much of a mess on the wings at FL240 where the wing performance isn’t going to be all that stellar... exceeding the airframe limitation for cold... lots of nope nope nope there...)
Click to expand...
There is a minimum operating temperature limitation for the TKS system in the SR, -30°F/-34°C. That number doesn't appear to be universal, so it may be airframe related. If I understand it correctly, the concern is that the alcohol in the mixture begins to gel (like that vodka in the freezer but more so). The result is that ice crystals which would normally not adhere at those temperatures, mix with the gel and produce slush.

That's the limitation I'm betting on based on the pattern. The other limitation I was thinking of is more universal - the system is not effective in freezing rain or drizzle.
 
Mtns2Skies said:
If fuel tanks can get water in them from condensation I don't see why TKS tanks can't. If TKS is water soluble, which I assume it is, then as the condensation/water enters the tank it can raise the freezing point. Just my theory.
Click to expand...
TKS tanks are tiny compared to fuel tanks so the amount of condensate will be minuscule. The other word you are looking for is miscible rather than soluble and alcohols and glycols are usually miscible with water so TKS should be miscible.

(Damn MEs know how things go round-n-round but get lost with fluids if it’s not a hydraulic power system.)
 
denverpilot said:
Some on the right track, others way out to lunch. :)

Two aircraft systems limitations being broken in the photo. Both related.

Wings weren’t contaminated prior.

Not water in TKS System, but kinda close.

@bflynn hit it... temperature limits.

So here’s the deal according to a pile of Cirrus instructors:

Aircraft is at FL240 at -43C. Both the TKS and *airframe* operating limits are being exceeded.

Hmmm... buy a nice turbocharged airplane and in the winter you can outclimb your airframe temperature limits!

The TKS “juice” tends to “froth” at that temp and altitude and it “no workie”. People have seen it do it warmer depending on pressure and age of fluid.

In fact, it makes the mess seen.

So, other speculation is that someone left the fluid in the tanks all summer and didn’t drain and refill.

Scenario was a fairly inexperienced instructor took the photo and posted it somewhere not realizing he was playing with very bad things there. Just turn it on and go fly in the Flight levels, right?

Not much time in weather or ice, and a bunch of Cirrus instructors kinda jumped his butt. (Unfortunately I missed that part of the show...)

Someone kept the photo (nothing ever dies on the Internet right?) and reposted it for a learning tool.

Sooooo... review those systems and know their limitations!

(And no, I haven’t flown one and didn’t know the limitations myself, just thought it was a fascinating photo. That much of a mess on the wings at FL240 where the wing performance isn’t going to be all that stellar... exceeding the airframe limitation for cold... lots of nope nope nope there...)
Click to expand...
If’n an instructor thinks they need TKS at -40 degrees they have problems way beyond just operating limits. Anyway, return that instructor for re-grooving.
 
Is this an automatic system or pilot activated? I would hope it uses some sort of temp vs ice detected to initiate the TKS.
 
Velocity173 said:
Is this an automatic system or pilot activated? I would hope it uses some sort of temp vs ice detected to initiate the TKS.
Click to expand...
Pilot activated. The TKS is supposed to be activated prior to entering icing conditions.
 
midlifeflyer said:
There is a minimum operating temperature limitation for the TKS system in the SR, -30°F/-34°C. That number doesn't appear to be universal, so it may be airframe related. If I understand it correctly, the concern is that the alcohol in the mixture begins to gel (like that vodka in the freezer but more so). The result is that ice crystals which would normally not adhere at those temperatures, mix with the gel and produce slush.

That's the limitation I'm betting on based on the pattern. The other limitation I was thinking of is more universal - the system is not effective in freezing rain or drizzle.
Click to expand...

The folks on the other forum were saying -40C in the Cirrus training.

I did forget to share there was no supercooled water droplets or other precip of any sort. The airplane made that mess all by itself.

Clark1961 said:
If’n an instructor thinks they need TKS at -40 degrees they have problems way beyond just operating limits. Anyway, return that instructor for re-grooving.
Click to expand...

A number of Cirrus instructors agreed with that and a smaller number regularly flying jets in the Flight Levels said they’ve seen supercooled water droplets accrete ice at temps that low when “it shouldn’t have been possible”. One specifically knew his particular ice was formed by massive lifting from mountain wave.

I’m staying out of it, with no time in the Flight Levels in anything. Just sharing. Folks say they’ve seen stuff stick at -40C. I’m not arguing for or against.

Velocity173 said:
Is this an automatic system or pilot activated? I would hope it uses some sort of temp vs ice detected to initiate the TKS.
Click to expand...

Most Cirri have a two stage pump Low/High for TKS, all pilot activated.

The newbie CFI was well admonished and took his post down after realizing he’d posted that he flew the aircraft outside of its airframe temperature limits. Not something you leave online after ten other folks whack you upside the head, I suppose. Learning experience. Apparently Cirrus doesn’t like what their plastic brew does at those temps. Let alone the TKS mess.

Numerous folks in the re-post let him know with that mess on the wing at that altitude he was really playing with fire and didn’t realize it. Bullet, missed. Lived to fly another day.
 
denverpilot said:
..................................

.
Scenario was a fairly inexperienced instructor took the photo and posted it somewhere not realizing he was playing with very bad things there. Just turn it on and go fly in the Flight levels, right?

Not much time in weather or ice, and a bunch of Cirrus instructors kinda jumped his butt. (Unfortunately I missed that part of the show...)

Someone kept the photo (nothing ever dies on the Internet right?) and reposted it for a learning tool..........................
Click to expand...
Was there identifying info in the posts? Has FSDO called him yet
 
denverpilot said:
Photo floating around some other sites at the moment. Worthy of a thread here...

40f1531d95569aa855a0966770a52669.jpg


That’s a FIKI TKS SR-22T.

Hmmm. How does that happen? And what’s going on?

(I know from reading it elsewhere but I’ll let y’all discuss first.)
Click to expand...

Nate,

I have only worked on one plane with TKS and the mission at the time was to stop it from leaking all over the owner's hangar floor. I don't understand what the photo is showing.

I put on my dunce cap when I got out of bed this morning. LOL.
 
denverpilot said:
The folks on the other forum were saying -40C in the Cirrus training.
Click to expand...
You can read it yourself... Top of page 4, although I can imagine either different numbers for different variations or instructors talking about the buffer in the numbers (the way some do about weight and balance limits).

I happened to recall something about this when I almost had access to one of these (I did fly it once with an instructor, but way to expensive to get checked out for personal flight). Looking at it reaffirmed there are certain things you really want to read the POH (and supplement) extra closely. Ice protection whether FIKI or not, is definitely one of them in my book.
 
The TKS system works by bleeding tiny amounts of glycol onto the leading edge of the wings, tail, rudder or where ever installed. The glycol combines with the moisture and produces a mixture which freezes at -76F.

Google make me smart. Huh, huh...
 
Velocity173 said:
Is this an automatic system or pilot activated? I would hope it uses some sort of temp vs ice detected to initiate the TKS.
Click to expand...
Three pilot selected options. Normal,high and max. The pump runs on a timer. I forget the exact cycle but it’s something like 30 seconds on and 30 off depending on which setting you choose. I’ve only had to use high once and it was short lived. If I have to use the max setting, I didn’t plan correctly. The 22 can hold 8 gallons of TKS. On the normal setting it gives you about 2.5 hours of fluid. There’s an Anti-Ice gauge and it shows the time remaining and gallons of TKS fluid.
 
labbadabba said:
I've seen something recently too that is a polymer onto which ice will not adhere. One of the applications listed was as a coating to wings of small aircraft.
Click to expand...

Yeah I think there's a company testing it on drones right now. Looks promising.
 
midlifeflyer said:
You can read it yourself... Top of page 4, although I can imagine either different numbers for different variations or instructors talking about the buffer in the numbers (the way some do about weight and balance limits).

I happened to recall something about this when I almost had access to one of these (I did fly it once with an instructor, but way to expensive to get checked out for personal flight). Looking at it reaffirmed there are certain things you really want to read the POH (and supplement) extra closely. Ice protection whether FIKI or not, is definitely one of them in my book.
Click to expand...

Shrug. Just passing along what they’re saying. They also all claim to be Cirrus factory trained. :)

I “are” just a lowly spam-can driver. ;)
 
Norman said:
Nate,

I have only worked on one plane with TKS and the mission at the time was to stop it from leaking all over the owner's hangar floor. I don't understand what the photo is showing.

I put on my dunce cap when I got out of bed this morning. LOL.
Click to expand...

It’s TKS “gelling”/“freezing” all over the top of an airfoil in flight, at night, near or in mountainous terrain. :-(
 
luvflyin said:
Was there identifying info in the posts? Has FSDO called him yet
Click to expand...

Those who saw it claim there was, but I didn’t see it, so I don’t really know.

It had to be quick because I usually have notifications set up on various aviation groups and if I’m bored or waiting on something, I’m reading them. And I had some hours of downtime the last two mornings before work due to scheduling and gigs and dogs and whatnot.

I think from the descriptions of the people in the repost comments various experienced Cirrus instructors probably already gave the kid enough of a hard time he won’t forget the lesson. Enough trauma there that I doubt a FSDO call would be much more than an “I know... I KNOW... I missed it...” kind of phone call. Hahaha.
 
denverpilot said:
Photo floating around some other sites at the moment. Worthy of a thread here...

40f1531d95569aa855a0966770a52669.jpg


That’s a FIKI TKS SR-22T.

Hmmm. How does that happen? And what’s going on?

(I know from reading it elsewhere but I’ll let y’all discuss first.)
Click to expand...
I wouldve freaked out.

Sent from my big plastic brick.
 
For me FL240 at night in icing conditions would be like trying to fly to the moon.
 
denverpilot said:
Aircraft is at FL240 at -43C. Both the TKS and *airframe* operating limits are being exceeded.

Hmmm... buy a nice turbocharged airplane and in the winter you can outclimb your airframe temperature limits!
Click to expand...

I've heard of upper temperature limits on composite planes, but not lower limits. Where are these airframe temperature limits defined? I didn't see them in the POH, but I'm not a Cirrus guy, so maybe I don't know where to look.
 
GeorgeC said:
I've heard of upper temperature limits on composite planes, but not lower limits. Where are these airframe temperature limits defined? I didn't see them in the POH, but I'm not a Cirrus guy, so maybe I don't know where to look.
Click to expand...
If they existed, they'd be in the limitations section .
 
What kind of oxygen mask, o2 flow rate and o2 cylinders does the cirrus have?
 
TKS being sticky discussing ****, it's going to collect whatever dirt and polution you fly through.
 
Last I checked, one of the limitations to the FIKI airplanes is that you aren’t supposed to fly it in freezing rain. I don’t know what that looks like on a wing but if I had to guess it would look something like that
 
I don’t understand why anyone would choose to run the TKS pump when the OAT is well below -20C. Airframe icing cannot occur at such a temperature, right?
 
The composite aircraft that I work on fly to -50c.... there is more of a problem with Hot / Wet conditions, however, that cold lots of systems start to shut down...
 
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