Extreme cold temperature winterization

[jlunseth]

I have not inventoried the many things in the engine compartment that are not a part of or directly attached to the engine, but there are probably several other than the air/oil separator on which I learned my lesson. The brake reservoir and related stuff is probably happier if the fluid is not completely congealed, etc. I liked the earlier post about warming the entire plane in a hangar which would warm everything but it raises another issue. A few years ago we had a really excellent pilot/instructor who put on Saturday morning seminars at Modern Avionics at KFCM. He did one on cold temp ops. One of the things that stuck with me was the choice between heat soaking and cold soaking an aircraft before a cold weather flight. So, basically, icing occurs when the temps are between +5 and -15 degrees. Warmer and no ice is likely, colder and any moisture has generally already found a way to freeze in the atmosphere. So if, for example, one wanted to take off and fly through a thin layer of clouds with possible icing, which we get around here quite a bit during the winter, and the ground temps are at around freezing, warm soaking the plane in a hangar the night before would help. The airfoils would be warm at takeoff and would discourage the formation of ice. But if taking off in super cold temps and, say, climbing into the flight levels, cold soaking is preferable because having warm surfaces would melt the ice crystals onto the wings where they refreeze into icing, whereas cold surfaces would not have the same effect. I don’t have a choice to warm soak so have not practiced this alot, and the pilot/instructor was flying turbine aircraft at the time so the issue is somewhat different than what we piston pilots experience, but I thought it was worth mentioning. 

Oh, and don’t forget to bring a windshield scraper/brush and a rag. I have had frost form on the wings in International Falls at -10dF in about an hour. Even better would be a garden sprayer with TKS.

[exM20K]

11 hours ago, jlunseth said:

Even better would be a garden sprayer with TKS.

A garden sprayer with RV antifreeze would be a cheaper and environmentally safer option. 
-dan

[jlunseth]

15 hours ago, exM20K said:

A garden sprayer with RV antifreeze would be a cheaper and environmentally safer option. 
-dan

I would certainly go with cheaper. I have not tried what you suggest. All I can add is that when TKS first came out, the immediate question was whether it would corrode parts on an aircraft. The discussion I remember is that the fluid would run back and embed in things like aileron and elevator joints, where there are different metals. I have not ever heard of that happening with TKS and I imagine (but do no know for sure) that it has been tested and found non-corrosive. Something not tested for aircraft use would be an unknown. I just don't know what the effect would be, can't say one way or the other. RV antifreeze is supposed to be safe for the environment, we use it in our sailboat every winter, but what its effect is in multi-metal situations I just don't know.

[Pinecone]

I guess you have not seen the reports of TKS fluid causing corrosion.  Especially if the fluid is a couple of years old.

[exM20K]

9 hours ago, jlunseth said:

I would certainly go with cheaper. I have not tried what you suggest. All I can add is that when TKS first came out, the immediate question was whether it would corrode parts on an aircraft. The discussion I remember is that the fluid would run back and embed in things like aileron and elevator joints, where there are different metals. I have not ever heard of that happening with TKS and I imagine (but do no know for sure) that it has been tested and found non-corrosive. Something not tested for aircraft use would be an unknown. I just don't know what the effect would be, can't say one way or the other. RV antifreeze is supposed to be safe for the environment, we use it in our sailboat every winter, but what its effect is in multi-metal situations I just don't know.

TKS is corrosive for sure.  I had a spot on the leading edge inboard bottom of one horizontal stabilizers, just aft of the panel.  I’m good about spraying Corrosion. Inside the tail after a TKS flight.  I’ve heard reports of others, too.  No big deal, but you have to stay on top of it. Bonanza and baron wing spars with their piano hinge fastening also require close monitoring.  I don’t recall the corrosion mechanism exactly, but I believe it has something to do with the hydrotropic nature of the fluid entraining water on surfaces.

The pink RV antifreeze is made of propylene glycol, which is non-corrosive and pet/wildlife safe for incidental contact. TKS fluid is nasty stuff, and I’ve become increasingly mindful in using off-label or handling it.

-dan

[65MooneyPilot]

Type 1 deicing fluid is propylene glycol mixed with water 50/50 mix heated to 150 degrees F. Good for removing ice contamination on the airplane. Many years ago we had a 55 gallon drum of it with a band clamp heater on the drum. We put it in a weed sprayer and sprayed it on the top of MD-80 wings before they installed heaters. This is a good deicing solution. Obviously if it is still precipitating you cancel the flight if you don’t have FIKI capability.

[jlunseth]

2 hours ago, 65MooneyPilot said:

Obviously if it is still precipitating you cancel the flight if you don’t have FIKI capability.

Yes, we were talking about removing frost that forms on aircraft on the ground in cold weather.

[65MooneyPilot]

50 minutes ago, jlunseth said:

Yes, we were talking about removing frost that forms on aircraft on the ground in cold weather.

Yes, then type 1 deicing fluid is for you. 

[Pinecone]

Hard part is getting it that hot.  Unless you have actual deicing equipment available.

 

[65MooneyPilot]

 

55 gallon drum, band clamp heater, hand sprayer. This setup was certified by the FAA. Just had to log the temp and mix ratio before using. 

[Pinecone]

I meant hard to heat up a garden sprayer.

I was using it on a 182 that was on a tie down and used by several pilots.  So it sort of needed to stay with the plane.

[blaine beaven]

15 hours ago, Pinecone said:

I meant hard to heat up a garden sprayer.

I was using it on a 182 that was on a tie down and used by several pilots.  So it sort of needed to stay with the plane.

Buy a battery blanket or two and zip tie them around the garden sprayer filled with fluid. Plug it in for a couple hours before your flight. All the warm fluid you could want. 

[carusoam]

a decade ago…

the local flight school used a garden sprayer and RV anti-freeze on the wings of their ifr training C172s…

worked pretty well… at getting frost off the wings prior to flight…

 

20°F is a memorable temperature…

above 20, the plane can be started with ample pre-start priming… (technically)

below 20, preheating the intake system is the minimum requirement to get fuel to evaporate…

 

if looking at physical properties of 100LL temperature vs evaporation / vapor pressure gets really low at and below 20°F…

But… don’t use this minimal required heating method on an engine that you like…

it’s enough to get the engine started,  it does nothing for getting the oil warmed properly or melting any moisture that has collected in places like the oil cooler, fuel sep, or case vent…

 

for engines that you like…

40°F is the common pre heat temp to reach prior to a regular start…

A good engine heater heats the oil, block and cylinders…

putting de-icer in the fuel tanks is covered in some POHs winter operations section…

 

PP thoughts only, not a cfi or mechanic…

 

Best regards,

-a-

[Pinecone]

8 hours ago, blaine beaven said:

Buy a battery blanket or two and zip tie them around the garden sprayer filled with fluid. Plug it in for a couple hours before your flight. All the warm fluid you could want. 

The issue was the plane was outside and multiple pilots.  There was power, but the big issue was the sprayer needed to stay in the plane so accessible to everyone.

If someone had wanted to spend the money, we could have put a cellular switch on it, and put it in a dock box, so anyone could turn it on the night before they thought they might need it.  But a bunch of CBs

 

[Pinecone]

8 hours ago, carusoam said:

But… don’t use this minimal required heating method on an engine that you like…

it’s enough to get the engine started,  it does nothing for getting the oil warmed properly or melting any moisture that has collected in places like the oil cooler, fuel sep, or case vent…

 

for engines that you like…

40°F is the common pre heat temp to reach prior to a regular start…

A good engine heater heats the oil, block and cylinders…

I only have an oil sump heater pad.  I am in an unheated, uninsulated hangar.  But with only the sump heater and an insulated cowl cover and cowl plugs, everything under the cowl is warm.  I put a remote thermometer in and the space was heated to over 60 degrees.  And the cylinders were warm to the touch.  Starting was simple and quick.

[jlunseth]

On 2/4/2025 at 8:38 AM, Pinecone said:

I meant hard to heat up a garden sprayer.

I was using it on a 182 that was on a tie down and used by several pilots.  So it sort of needed to stay with the plane.

Well, and remember there is the getting home part too. So if you fly to a small rural airport and don’t have everything with you that it will take to start the plane and fly it home, it will sit where you last left it until spring thaw. So whatever method you are going to use to defrost the surfaces, you need to have that with you in the aircraft like Pinecone says. If you are going somewhere that has a robust FBO they probably can deice, you probably have the choice of hangaring inside, and they probably have a propane heater to warm the engine. Many airports do not. I have run into situations where, if you did not call ahead, even the better FBOs can’t help. I made an unplanned stop in Flagstaff last spring and asked to have the plane hangared overnight. They could not, the hangars were full. Got an inch of freezing rain and then crusty snow overnight. I got lucky though, the sun came out and helped clean the plane. Whew!