swissflyer

Hello

I have a question for everybody, but specially for our "Nordics" friends:

What kind of methods,tricks, or solution do you have for winter flying,
for starting turbines with gas??

Actually i don't have to much problems, a "shake" [>:] on the model when the turbine is on ignition phase is
enough to get the gas out of the tank, but for the colder time i'm thinking some methods to get
the propane/butane mix out of the tank, and before i put some in service i was wondering, how the others do...

My mix is 70/30 There are others, Better mix for colder time?? or what do you do?!???

Thanks

Alessio

trioval00

My Feedback: (17)

Alessio , we were out yesterday flying, i have a jetcat p-80. the only thing i do is keep my start up fuel -powermax- in the truck and keep it warm, and just before start up i fill the system in the jet. it was only in the low 30's high 20's yesterday. but all i found was to keep the start up fuel warm

as always, just my thoughts

mark

jonjon

Alessio

I have run my AMT turbines , both auto and manual start down to around -10 C with no problem just by keeping the gas can in an inside pocket of my flying suit right up to the point I need to use it. In this way I have never had a problem starting but the old trick of flicking a V SMALL amount of liquid gas into the gas line by shaking the can can help. The thig to watch is that you have enough gas flow otherwise the motor will not get hot enough to start the fuel pump. I use 4mm O.D festo tubing for my gas line and for the gas valve I use a drilled out areosol fitting that is supplied with cheep sprayguns.

As an aside you should see the amount of power turbines produce when it is this cold.

Hope this helps

John Greenfield

MDEE

We use propane for our AMT engines in the North of England, we have stopped using mixed gases. Even a wren has been difficult to start on mixed gases in cold weather. I always keep the gas warm inside the house, never leave it overnight in the car or in a cold workshop

SAP_2000

As the other guys said, just keep the gas bottle warm inside the car or as we do inside our thermo suits. And don't use the on-board gas tank as it will quickly cool the propane gas down. Just connect the the tube from the warm gas bottle directly in to the engine or propane valve.

Also remember to have some condense remover like Isopropanol in your retract air system to prevent freezing in sub zero temps. Do this at home before you fly and cycle the gear a few times to get it out in the retract cylinders. That will remove any condense from your air system and then it can't freeze. Also remember to use a condense remover that is made for use in air systems. This one will not dry out the O-rings.

I have not experienced any other issues with using turbines in cold weather. The coldest temperature I have ever flown in was -20c, and I can tell you that you get a lot more power from your turbine in that temp compared to what you get at +25c in the summer.

Good luck, and remember to warm your frozen fingers in the hot exhaust before you fly[sm=thumbup.gif]

swissflyer

Thanks everybody...

my ideas are more "extremes" [>:], as i cannot get te car nearby the flying field (only to unload/load is allowed, but for flying she must be away...) and we don't have any flying field house...

one of my Extreme idea was to use a model tire warmer, the ones used by the R/C model car, and heat up the gas bottle for a couple of minutes, and then start the turbine...[8D], the only problem is not let the bottle overheat..

but i think that keep the gas bottle inside my jacket will be enough....

mack845

Cold weather starting,
The 70/30 mix is slow to boil off, the 30% propane will boil off first, so leaving you with a weaker mix.
Use a 4 inch diameter camping gas container that has been emptied and decant neat Propane into it.
Create an outside starting trolly/box with a buggy battery and this container.
The 4 inch dia gives a boil off surface some 15 times greater.
OR
The onboard gas canister should be canted over as much as possible without supplying neat propane gas to the turbine to increase the surface area.
OR
Make your own canister with ribbing/fins
and one last canister, if you must have an onboard canister,and if you have enough room make a canister out of the throw away type, by reducing its height . mine is 2 1/2 " tall ( 8 times boil off surface)
Norman
UK agent for Behotec turbines

Falcon 64

Also get yourselves a PROPANE bottle, not a Butane/Propane mix.
The propane keeps the pressure in cold weather much better than the mixtype.

Gudmund