Some thoughts about flying in cooler weather

Hi everyone -

Frost on the field, temperature -2 C/28 F...check

Two Russian park jets ready to rip up the skies...check

Fire lit in the clubhouse wood stove so pilot can get warm...check

So you might be wondering why someone would be crazy enough to fly when the temperature is below freezing... :/?  Well, sometimes I ask myself that, but this time of year where I live it can be some of the best flying weather we have as the winds are calm and the nice cool, dense air helps give good lift and great air for the prop to bite into.

Like very hot weather that some folks are experiencing in the southern hemisphere now and which I wrote a few thoughts on here http://migsrus.blogspot.ca/2014/07/motoresc-performance-in-hot-weather.html , colder weather can also present it's challenges to park jet flying.  I have found that when temperatures are between 5 C/40 F and 25 C/77 F, I don't worry too much about things getting too cool or too hot, but once the temperatures get outside that range, experience has taught me to adjust my flying accordingly.

Now cooler weather flying is probably a bit more of a challenge as not only does the plane have to be treated with care, but the pilot is normally affected more by cold than heat as well... :/

Obviously we don't need to worry too much about ESCs or motors getting too warm, but batteries are another story in my experience.  What I have found is that as the temperature drops below 5C/40F, batteries tend to discharge a little faster and if they are a bit older can have a tendency to discharge more unevenly.  My personal rule of thumb is to not run my batteries down below 3.7 volts per cell.  So to be on the safe side, I shorten my flight times by about 30 seconds to help extend the life of my batteries.

I also try to keep my batteries warm by keeping them in my pocket inside my coat until I am ready to use them or if I have a bunch, I leave them in the little clubhouse where they can stay warmer after I get the fire lit in the wood stove.  Then when I expend them, I also keep them warm so that they don't get too cold as I am continuing to fly, again I am lucky to have a warm clubhouse in which to leave them.  Then when I get them home, I ensure they have warmed up to about room temperature before I put them on the charger.  By following these rules of thumb, I have had good experience now going into my third winter of flying.

Another area to keep an eye on is servos.  I store my planes in the garage, so they are "cold soaked" when I put them in my car and don't get warmed up much on the short drive to the field.  Anytime I have ever stripped a nylon gear servo, it has been cold and I have been too aggressive too soon.  I find that by taking it a bit easy during the first part of the first flight with a plane allows some current to run though the servo and get things warmed up and worked in so that gears, etc are not so brittle and less likely to break/strip.

I think it is also a good idea to give the plane a quick inspection as well, especially if it has been stored in the cold for awhile to ensure all the glue joints are good.  I have found that Foam Tac is a bit more resilient to cold than hot glue.  Sometimes hot glue will pull away from the foam as it gets really cold (ask me how I know this... :/), so it is a good idea just to check all the important joints are still in good shape before flying.  

So what about the pilot?  Well obviously dressing for conditions is important, I find that with all the standing around while flying, my feet can be most susceptible to get cold, so I have good winter boots with thick duffle sock liners that keep my feet toasty.

Hands (ie thumbs) are another story, I guess some of it depends on a person's tolerance to cold and the conditions.  Fortunately when I was flying yesterday, the sun was out and that helped keep my hands warm enough that I had pretty good dexterity for my flights, and then I just put gloves on in between to keep my hands warm. 

 There are lots of options.  I have seen other guys use one of these radio muffs at my field, but since we hand launch our park jets, it might be tough to get your hand back in there quickly enough.  Or even tougher to find someone to come stand in the cold and launch your planes for you... :/

I am a "thumb" flier as opposed to being a "pinch" flier, so having good feel between my thumb and the end of the transmitter sticks is important to me.  I have found using different sticks on my radio has been helpful in the past although the ones I use now have pretty good "sharp" points on the top, so I continue to get good feel even as my thumbs get a little cold. http://hobbyking.com/hobbyking/store/__23762__Alloy_Anti_Slip_TX_Control_Sticks_Short_Futaba_TX_Red_.html

I have also used these big "Turbo Thumb" http://hobbyking.com/hobbyking/store/__12996__TurboThumbs_Super_Big_Futaba_Rocker_1pair_Red.html sticks in cold weather with good success, but don't find them quite as precise a feel as the ones above, but then they have "Turbo" in the name, so they do have that going for them... ;)

In conditions when the sun isn't out and my hands do get cold a little faster, I have flown using military issue flying gloves that I was lucky enough to be able to keep after I retired from the Air Force.

These gloves fit pretty snug and still allow me decent dexterity.  I have also seen folks with cheap wool gloves cut just an inch off the end of the thumb and index finger of the glove so they can still have good dexterity to fly and work switches with bare thumb and finger tip.  I have also seen folks use the glove/mitten combo below, that way you can just flip the mitten part back over your fingers and thumbs between flights to warm them back up.

Of course I am pretty blessed to be able to go into a nice warm clubhouse and warm up every few flights or so if I need to.  Many folks in the northern hemisphere are finished flying (other than those who can fly something indoors) for the year right now and focusing on building, but like I said if you can, it is normally a great time to get out and sneak in a few flights if you take care of your gear and yourself... :)  I always feel a bit more motivated to build something after I have been out on a cool, crisp day ripping up the skies with my plane... :)

Cheers,

Scott