More thoughts on severe cold flying

[aviatoreb]

Background and then story:

 

We are not getting the blizzard you are seeing in the news in Boston/NYC, etc.  We are getting severe clear but severe cold.  -10F for a high yesterday, -5F for a high today ... -25F last night and early this morning, and -15 for tonight.  Then it is warming.  25F for tomorrow and 35F for Sunday.  Can you imagine tomorrow at 25F will be 50F warmer than this morning.

 

Today was -5F when I went to the airport but I did not fly - it was severe clear and light winds and beautiful -white bright and gorgeous - but I could not fly since I had not expected good weather so I had not plugged in my cabin heater and I will not abuse the instruments in these extreme temps by cold starting.  Engine is toasty 24/7 with the rieff turbo xp.  I know - I know....  I believe in it.  The unexpectedly warm -5F is right at my minimum so I would have flown if I had thought to pre-heat.  

 

For sometime I made -10F my personal minimum for flying since I am wary of an off field landing becoming dangerous even if you are in good shape and near help in extreme temps.  And yes I do carry a good bit of cold survival gear but at some point enough is enough.

 

Then not too long ago I made it -5F (on the ground) for the same reason, plus I decided it is just not fun getting the airplane ready when it is very cold. (But my cabin heat is no problem - great cabin heat in my rocket!).

 

But I am thinking of raising it a bit to 0F.

 

Yesterday I had a seemingly inconsequential "event" in my car that really gave me pause of how much such severe cold is a stress on our equipment.

 

-I wanted to drive my 15 year old son to Ottawa to the Canadian air museum.  -18F at mid morning (colder with the wind chill ... - 35F).  So I jumped in the minivan - our toyota sienna awd...cuz of the heated seats.   The battery was too weak for the task.  Time for a new minivan battery.

-So I jumped in my favorite car, my daily driver, my subaru wrx sti. Love it. Awesome winter car.  (but no heated seats).  Started right up - with just a little protest.  Let it sit and warm up for 5 min.  Then off we went to the gas station since only 1/4 tank.  No luck.  I can't fill up with fuel.  No way no how.

 

Here is the scary part: the gas tank open lever is at the driver side seat.  The pull lever is frozen in place.  But not by water.  I presume it is a cable like a bicycle cable, or an airplane cable.  With different metals for the sleeve and the cable, which expand and contract at different rates.  At -18F the cable sleeve had contracted so much around the cable that it is frozen in place. I mean absolutely frozen in place.  I cannot fill up until tomorrow.

 

Can you imagine if such a thing were to happen to your primary controls in your Cessna or your Piper?!!!!  I know we have push rods in our lovely mooneys, but we do have some cables like the engine controls.  Yay for preheating the cabin.  Still - not everything warms up when you fly the plane - like the equipment back in the tail gets awfully cold at altitude.  What other strange effects are there in frigid cold?

 

Oh - and my subaru wrx sti I found this morning had a mostly flat driver side tire - sometimes tires spontaneously deflate in frigid cold - they loose a lot of pressure in cold and then a lot of air can escape.

 

-After car number 2 failed yesterday I took my wifes subaru baja, with no problems.  Air museum was terrific.

 

Still...I have been thinking about that frozen cable all day today and how much more dire that would be in an airplane in flight.

[pinerunner]

Good thinking. We have pushrods instead of cables but those need to be greased and I wonder what happens to that grease at really low temperatures.

 

I'm being cautious about winter flying.  I also watch for what the folks flying in Minnesota have to say about frigid flying since there are quite a few Mooneys there and a service center too.

[carusoam]

That's why our planes are tested to a much higher degree!

Similar problems exist with Mooneys, however. If your plane sits outside in the rain, followed by freezing cold temps. You wil have the fuel caps iced in place. Your trip to Florida will be delayed while you get a ziplock bag filled with hot water to sit on it for a while...

Experience from 2 years ago....

Best regards,

-a-

[aviatoreb]

Good thinking. We have pushrods instead of cables but those need to be greased and I wonder what happens to that grease at really low temperatures.

 

I'm being cautious about winter flying.  I also watch for what the folks flying in Minnesota have to say about frigid flying since there are quite a few Mooneys there and a service center too.

 

Good point.  I wish the Minn. service center would write us a cold weather ops cheat sheet.

 

We do have cables at least in the engine controls.

Today - there was a transient M20J operating out of our airport.

 

Two things I really like about cold weather ops (not necessarily severe arctic....)

-My rocket climbs so fast that I have no idea how fast its actually climbing: the rate of climb indicator is calibrated to show up to 2000fpm and I can peg the needle that high and climb faster than that if it is 0F.

-On a severe clear day when it is still, and white snow everywhere - gorgeous.  And in the evening when the snow starts to glow blue after the sun sets and before it gets dark - gorgeous.

[BorealOne]

I think you'd be surprised at how well our planes perform in the cold, but there are limits to that made-in-Kerrville design. As Erik has intuited, the vernier cables are one of those limits. They have some plastic components that don't stand up to extreme cold. I learned this the hard way one winter in the Northwest Territories. The throttle cable failed in flight, forcing a deadstick landing in Yellowknife. 

 

I'm still flying in very cold temperatures, but am careful to ensure that both the cabin and the engine are up to temp before departure and pay close attention to any resistance in a cable or other control.

[rbridges]

It's balmy here relative to you guys, but it did dip into the 20's last night with a high of 40s today.  I went to the airport and used the 60w light bulb trick I learned here.  I went back a few hours later and my oil temp monitor said 50 degrees.  Warm enough to take the plane out for a short flight.  

[Marauder]

I will say one thing, I am really pleased with the Reiff Turbo heater package. I flew on New Year's Day and turned on the heater 5 hours before I got to the airport. It was 20 degrees out and the cylinder temps were all in the 150 range and oil was 110.

Sure don't missed my propane heater

[jlunseth]

There are odd things that happen in very cold temps that you don't think of until you see them.  An oil cooler block definitely needs to be installed.  I flew the plane out to Willmar in early Dec. to have the oil changed and the block put in.  It was later than I would have liked.  My CHT's were nice and cool, which is nice, but the oil temps hovered right around the 100 degree minimum and a couple of times dipped below.  I found myself operating the engine as hot as I could, just to keep the temps up.  On the trip home after the block was installed, OT was not a problem.  Right where it should be.

 

A couple of years ago I had the air oil separator freeze due to condensation.  That blocks the relief of pressure that occurs in the crankcase and exits the breather tube.  So oil blew out everywhere.  What a mess.  No damage fortunately, it happened on takeoff and I went right back in and landed. 

 

We get temps here in MN where at least in the old days, with the older metals in cars and farm implements, when iron and steel would simply become brittle and break.

 

Last but not least, it is pretty hard to get the cabin of the aircraft to warm up much even with the heater on full bore.

 

I find it "unfun" below about 20 dF, and no go at zero, whether you are equipped for an off field or not.  The planes were made in TX and they did not think much about cold weather effects.

 

I can fly all summer long in the flight levels where the temps are -25 or more without a problem and with ample heat in the cabin, but the air is thin up there and does not cool much.  When it is -20 at ground level, the air is very thick and cools things very rapidly.

 

Some ice on the runway does not bother me, the idea of an offield does not bother me, but the idea of sitting in the cabin for a couple of hours with the temps in the 20's, that is not much fun.

[Piloto]

For cold weather knobs and buttons are better than touch screen when wearing gloves. Specially on the ground when setting your flight plan on the GPS. That is an advantage the GNS-530 has over the GTN-750 and tablets.

 

José 

[jlunseth]

Amen.  You have to take your gloves off for a touch screen, even for an iPad.  I was doing that yesterday, but yesterday it was 30F here and the heater was doing some good.  Last ten days it was as cold as -25F at night and one day the high was around -20F.  The plane sat in the hangar and I have a fire going in the fireplace.

 

One other thing people do up here in the cold is to plug in their engine heater, take the oil cap off, and let the heater run full time.  The idea is to keep from building up moisture inside the engine.

[FlyDave]

Amen.  You have to take your gloves off for a touch screen, even for an iPad.  I was doing that yesterday, but yesterday it was 30F here and the heater was doing some good.  Last ten days it was as cold as -25F at night and one day the high was around -20F.  The plane sat in the hangar and I have a fire going in the fireplace.

 

One other thing people do up here in the cold is to plug in their engine heater, take the oil cap off, and let the heater run full time.  The idea is to keep from building up moisture inside the engine.

I got a thin pair of gloves from KMart that have pads on the index finger that work on touch screens without taking off the gloves. They work fine with a little practice.

[aviatoreb]

I'm just taking my gloves on and off constantly - but I keep meaning to buy some of those gloves that are fingerless but the index finger pulls off.  Ever seen them?  They are cool.

[Marauder]

One other thing people do up here in the cold is to plug in their engine heater, take the oil cap off, and let the heater run full time. The idea is to keep from building up moisture inside the engine.

I think this had been discussed before, but gotta ask it again. I was told years ago that it was bad to run a Tanis or Reiff heater constantly because they never get the engine hot enough to boil off the water. It was described to me that all you are doing by running the heater is creating a sauna in your engine with the moisture unfrozen which wouldn't be the case if just let it stay frozen. The other concern was that heating the engine constantly allows the oil to flow and come off the parts it is there to protect.

Taking the cap makes sense, but is that sufficient to evacuate moisture in areas of the engine where there is no possibility of the moisture escaping?

So what is the final word on this? Okay -- maybe another round of discussions

[Marauder]

I'm just taking my gloves on and off constantly - but I keep meaning to buy some of those gloves that are fingerless but the index finger pulls off. Ever seen them? They are cool.

You mean hunting gloves? There are gloves designed specifically for using touchscreens. Let me see if I can find an example. Ah, here you go: http://store.apple.com/us/product/HB818VC/A/moshi-digits-touchscreen-gloves-sm?afid=p219|GOUS&cid=AOS-US-KWG-PLA

[Jeff_S]

I think this had been discussed before, but gotta ask it again. I was told years ago that it was bad to run a Tanis or Reiff heater constantly because they never get the engine hot enough to boil off the water. It was described to me that all you are doing by running the heater is creating a sauna in your engine with the moisture unfrozen which wouldn't be the case if just let it stay frozen. The other concern was that heating the engine constantly allows the oil to flow and come off the parts it is there to protect.

Taking the cap makes sense, but is that sufficient to evacuate moisture in areas of the engine where there is no possibility of the moisture escaping?

So what is the final word on this? Okay -- maybe another round of discussions

 

I have a Tanis system in my J. Since it's not often that cold here in Atlanta, I'll just plug it in if I know it's going to be freezing overnight and I'm flying the next morning. But when I get out to the plane, while the engine is warm to the touch, I wouldn't call it a "sauna" by any stretch. It doesn't seem to get the engine warmer than about 50-60 degrees, based on the readings on my JPI 700 when I start it up. And since the oil and the engine block are all the same temperature, I don't think this would cause any real condensation problem. But perhaps this is of more critical consideration in colder climates where the temperature differential is greater.

[fluffysheap]

You can also get a capacitive stylus designed for writing on touchscreens.  Stick it in the pencil holder (do all Mooneys have those, or just mine?).  I'm sticking with my 430, wouldn't want a touchscreen, it's just going to cause problems.

 

It's not rare for me to see -30 temps in the flight levels.  How cold does it have to get to cause oil temperature problems?  My thermowax keeps the oil right at 170 when it's cold enough to keep it that low.

[yvesg]

It depends on the Pour rating of the oil you use. I would try to always stay a couple of degrees about that temperature. Check the other threads... Aaron ran into such issues recently.

Yves

[Piloto]

I have a Garmin 560 with touch screen that works very well just using a retracted ball point pen. Unlike the GTN 750 or the tablets that has capacitance touch screen the 560 has contact screen. 

 

José

[John Pleisse]

Not discussed is dealing with plugs that get frozen over. Once this happens, you'll use your entire battery. Prime, hand pull the prop two or three blades (master off, key on glare shield), then get in and start. It works.

[jetdriven]

The aera came from the nuvi which was a motorcycle GpS marketed as "glove friendly" with a pressure touch screen.

[RJBrown]

I'm just taking my gloves on and off constantly - but I keep meaning to buy some of those gloves that are fingerless but the index finger pulls off.  Ever seen them?  They are cool.

Hunters gloves. Got to keep that trigger finger precise. I wear my hunting clothes then flying in sub zero conditions. Take a gun with me in the plane to. Dressed properly the cold is a no factor. Now is the best time to buy hunting gear. Christmas is over and they need to get rid of all the cold weather stuff. Preheat engine and cabin!  

 Airplanes love the cold, the performance is amazing. Air is much more stable. No ice concerns when its 0 on the ground. No convective weather. Vizibility is usually better. Except in Salt Lake with their near constant inversion.

[aviatoreb]

It's -29F this morning.    -40 with the wind chill (that 3mph wind....)

 

I'm gonna get me some hunting gloves and head out flying!

[yvesg]

Here it is either too cold or it is IFR in icy clouds. Have not flown for 2 weeks!

Yves

[Bob_Belville]

The 750 touch screen will spoil you but many entries can be made with the large and small knobs.

[aviatoreb]

Here it is either too cold or it is IFR in icy clouds. Have not flown for 2 weeks!

Yves

 

Tell me about it.  I was just kidding.  I won't go flying when its this cold.  Personal mins -10F on the ground but rarely do I want to below 0F.

 

Actually, smartest thing I did this year was to put my airplane into annual two weeks ago, two months early.  She is sailing through annual with no major issues this year, other than the expected schedule mag oh, and I am not missing her with this weather.  Hopefully she comes home end of next week.

 

Meanwhile, predicted back down to -25F tonight.

 

I was up in Gatineau XC skiing on Sat.  It was nice.