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Another winter ops / preheat question

TShort

Well Known Member
I am pretty meticulous about preheating before I fly (Reiff system on the -10).

I'm planning a trip where I likely won't have hangar space on the other end for a few days. No precip forecast, but night temps are looking like 25-30F or so, with forecast highs on departure day of 48F.

I don't think I'll be able to plug in (looking into that now).

On a 48F day (likely sunny - at least in the forecast), how long does it take a 25-30F engine to warm enough to not be cold soaked? I am not planning on leaving until early afternoon.

Probably overthinking this, but interested in how others handle winter travel.

I am flying solo, so I could possibly throw in the 2kW generator and use that to preheat :eek:
 
Generator

I think the generator is a great idea, or land where you can get power.

Out of curiosity - which one do you have? Been looking at them myself, and want the lightest, quietest - seems to be the honda, but quite expensive. No idea if it's worth the extra cost.
 
When I'm forced to do a cold start, I idle at about 900 rpm until my oil temp reaches 80F prior to taxi, and wait until 100F for takeoff power.

Not saying that's right, or wrong... just that it's what I do.
 
If I lived in cold country, what I would do is have a quick release access door in my cowl for the following.

This is what I used to do when I flew GA corporate in Utah, Idaho,
Montana, and Wyoming in winter. Once 25 below in Jackson hole!

We carried around a bucket and funnel and upon arrival, drained the oil into the bucket and kept it either in a warm FBO office or even on occasion, took it to the hotel.
Upon arrival just pour it back in. Never had a start up or significant flight delay.

Obviously harder if you have to remove the cowlings hence access door recommendation.
 
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Instead of carrying around a generator, I would be more inclined to figure out a way to use a small "Buddy Heater" type heater that operates on 1# bottles of propane. When I owned a C-152 that sat out on the ramp in the snow, I devised a contraption using a 35K btu propane torpedo heater that I powered off a 20# bottle and 1000 watt inverter. I just sat in my car on the ramp by the plane as it warmed up.
 
Thanks for the input so far.

I don't mind starting if the engine is 45F, but don't really have a good idea how long it takes to get close to ambient after a cold night outside.

Still looking into plug in options...
 
Call ahead

I called ahead to the AP to make sure they have someplace to plug in. I?m tied down on a ramp in western PA now. I will go out and plug it in the day before we are leaving to go home. I think you will find a lot of AP?s are accommodating even providing cords.
 
I don?t see anything wrong with starting your engine at 45*F, especially if using multi-viscosity oil. It won?t take long to get your OT up to a good takeoff temp ~90*. I was in Troy, MI a few years ago for an overnight and brought my extension cord and timer to use my engine heater before we left the next day. Unfortunately, the electricity in the hangars didn?t work - except for the electric bifold doors. The next day the temp outside and inside the hangar was 15*. The airplane started just fine, and after a slow, but not long taxi to the runway, and normal run-up, my temps were in the norm. Total elapsed time from engine start was about 15 minutes. It helps if you can safely allow your engine to run at 1000 RPM or a little more during the warm up phase before takeoff.
 
I started my engine yesterday with no preheat at 37F. It was painful and took a couple minutes. It was a good test of my battery, though
 
I would follow the Lycoming recommendation which is to just start it.

I live in a cold region and have never had an issue following their recommendation. I start down to 20F without preheat. I do use a good multi-viscosity oil and run the engine at 1500 rpm for 5-10 minutes until the oil reaches 100F before takeoff. Below 1000 rpm runs the risk of fouling plugs.

Also, use a primer if you have one, and the engine will start as quickly as on a hot day.

Aaron
 
Follow up.

I packed the generator in the back of the -10, as the destination airport is a pretty small / unattended place (8C4).

Yesterday the afternoon temps were in the high 40's with sun, and when I flipped the switch the oil temp was 44F so I just started as usual.
 
I am pretty meticulous about preheating before I fly (Reiff system on the -10).

I'm planning a trip where I likely won't have hangar space on the other end for a few days. No precip forecast, but night temps are looking like 25-30F or so, with forecast highs on departure day of 48F.

I don't think I'll be able to plug in (looking into that now).

On a 48F day (likely sunny - at least in the forecast), how long does it take a 25-30F engine to warm enough to not be cold soaked? I am not planning on leaving until early afternoon.

Probably overthinking this, but interested in how others handle winter travel.

I am flying solo, so I could possibly throw in the 2kW generator and use that to preheat :eek:

Thomas...after Atlantic wanted to charge me $75 for plugging in my airplane without asking when it was 40 OAT, I decided to go this route with an MSR whisper-light camping stove for the days I actually needed to preheat. You just use fuel sumped from your tanks...no power required. Uniformly warms entire engine and takes oil from 25 to 60 in about 30 minutes.

The only negatives I've found...
  1. The flame burns very clean and hot, so the stove glows red-hot and takes a few minutes to cool down before stowing in the airplane
  2. 100LL seems to plug up the fuel nozzle with lead...I switched to using mogas which leaves a smokey residue on stove

https://www.youtube.com/watch?v=3DGsJpqRFqg

Picture of my rig...all parts weight less than 2 lbs. when bottle is empty

preheat.JPG
 
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Freezing Point

When I was the chief pilot of a small Piper Navajo operation in northern Ontario Canada, we used the freezing temperature as the cut-off for pre-heat. Even the hangar was kept at 40*F overnight. We would push the planes out into -40*F and start them up right away. When out on a charter and waiting outside all day, it could easily be -25*F in the afternoon, so we would preheat the engines and use custom made engine blankets. It was too cold to use a camera, so I don't have any pictures to share ;)

One thing we had to watch was high oil pressure after start. We'd have to idle the engines at 800rpm initially and slowly increase RPM to about 1200 as the oil warmed, thinned and the pressure dropped from the maximum limit. Leaning aggressively to prevent plug fowling.

Engines were Lycoming 6 cylinder angle valve and a big turbo (TIO-540) running multi-viscosity oil. They routinely made it to TBO.

FWIW, I'll probably preheat my plane at warmer temperatures. Not for any concerns about the engine, but to reduce warm-up time and save gas. Plugging in extension cords and setting up engine tents all takes considerable time that a commercial operation doesn't want to waste. On a private plane, I'd rather save that couple dollars of fuel not idling and warming up as long. I plug in my cars at home at 15*F for the same reason.
 
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Thomas...after Atlantic wanted to charge me $75 for plugging in my airplane without asking when it was 40 OAT, I decided to go this route with an MSR whisper-light camping stove for the days I actually needed to preheat. You just use fuel sumped from your tanks...no power required. Uniformly warms entire engine and takes oil from 25 to 60 in about 30 minutes.

The only negatives I've found...
  1. The flame burns very clean and hot, so the stove glows red-hot and takes a few minutes to cool down before stowing in the airplane
  2. 100LL seems to plug up the fuel nozzle with lead...I switched to using mogas which leaves a smokey residue on stove

https://www.youtube.com/watch?v=3DGsJpqRFqg

Picture of my rig...all parts weight less than 2 lbs. when bottle is empty

preheat.JPG

This is more or less what I use, costs almost nothing in parts from a hardware store. I use my jetboil and carry a couple of cans of fuel, but it's also for making coffee and mountain house should the need arise.

I also have an engine blanket and with this combo I can have the oil temp at 70 degrees in 20 minutes when it's -10 out. I can also shut down, put the engine blanket on, come back in 6 hours and still have warm oil to.
 
Also... pull the prop through about 6-10 blades on those really cold days. Really loosens things up.
 
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