Jet A1 will always have a tiny water content. As you climb, the fuel gets cold and tiny ice crystals form.
Like a ‘Slush Puppy’ drink.
Those ice crystals can clog the fuel filter and eventually causes a flame out.
I also have this:
All the OLD 500 series Citations require 1 part additive to 1000 parts fuel.
The early CJs also mandate an ice inhibitor.
The King Air doesn’t require additive, because it has an oil heat exchanger in the fuel tank to keep the fuel temp just a degree or two above zero.
So Prist gets used a lot in these circles… People must get through a lot of disposable gloves because the stuff is nasty.
There’s also this PC-12 accident where icing caused extreme fuel imbalance and aircraft flipped over in the circuit.
Cobalt wrote:
Nor in a twin, given that if fuel for one engine ices up
Seems we had this conversation before. Cheers.
[ yes – I have merged the two threads – Peter ]
Peter wrote:
So Prist gets used a lot in these circles… People must get through a lot of disposable gloves because the stuff is nasty.
I used to fly a PC12 and never used gloves to put Anti Ice…
Most of the time the guy doing refueling do it or you use the bottle with the “funnel”. see: Here
On some airport up north fueler can mix the fuel and prist directly
Romain wrote:
Most of the time the guy doing refueling do it or you
Last year at Roskilde a fueling person would not go near aircraft once I pulled out the can. Had to refuel myself. Company policy he said.
In the Meridian I never used it in Europe. Over the NAT I did and Iceland and Greenland line guys had no problem with it.
Bromma(ESSB) used to have premix of prist in the fuel but stopped with that some years ago apparently. I use the ordinary bottle to fill it and just pour it in at the same time as the fuel guy is doing his thing. Most guys do not have a problem with it at all.
I have never used Prist/EDME but carry 1 or 2 1-litre bottles of IPA and throw half a litre of the stuff into the tank while it is being filled, if I am refuelling from a place where the stuff may have been sitting for a long time.
IPA should be completely safe and doubles as a handy degreaser.
Digging up this old thread as I want to take a TAE 125 engined cessna 172 up to FL180, just to see the curvature of the earth 
It’s filled up with diesel mostly and with that comes a temp limit. Before take-off the fuel needs to be above freezing and in flight the fuel must nog cool down below -5C. I was wondering how fast the temps drop in a fueltank at say -20C OAT. I could fill up with JetA but the handbook says if more than 10% of the fuel is diesel then these minimums apply.
