tchavei
rrProfessor
Location: Portugal
| Hi
Just wanted to leave a experience I just went through after 3 years mixing my own fuel.
As you know, on this side of the pond (read europe) its usually much more cost efficient to mix your own fuel. If you have the luck to have access to high quality components you will get fuel that is as good and sometimes even better than the comercial stuff. Another benefit is that you know exactly what you're mixing and can play with the proportions.
Anyway, for about the last 3 years, I've been mixing 20% nitro, 20% KL-198 Klots Heliglow synth oil and 60% methanol. I always used a pharmaceutical volume measuring tube to get the mix right to the last cubic mililiter. After that I always shake the jug of fuel for about 10 minutes to assure that all components blend into each other perfectly. Sometimes I even give the jug to my dog and let him play with it for half an hour 
I never considered this last part of the procedure of great importance because as those who mix fuel already know, the components seem to blend instantly together so one is tempted to skip the "shake it like an idiot" part.
Well, about two weeks ago, my YS50 suddently felt tired. I mean it started ok and generally worked ok but was much more prone to bogging with as low as 12 deg pitch. It seemed like I was running on strait fuel or the engine just had lost its punch. I played with the needles, checked my graphs and everything seemed ok (except for the sudden loss of power). I finally gave up, ordered the basics I needed to rebuild the engine and in the meanwhile I got a new YS from a friend.
Since I was practicing some new maneuvers at the time, I didn't want to have the downtime of swapping and running in the new engine so I decided I would just run the old one until it would finally give up.
Last week, while I was finishing my jug of fuel, I suddently realised that there was a good amount of raw KL-198 at the bottom and I couldn't feel that spiky odor from the jug... 2 seconds later I remembered that while I was mixing this jug, my kid called me for something and since I didn't want him to go to my shed (I was mixing fuel right?) I just closed the jug and didn't shake it...
So, basically I must have flown with like 50% nitro and 5% oil for the first 5 flights and then with like 2% nitro and 40% oil at the end. ROTFL.
Finally, I went home, mixed a new jug of fuel (this time properly), returned to the field, fired up the bird and behold... the beast woke up again and I was ripping the sky at 14 degrees 
NEVER EVER SKIP ON ANY OF THE STEPS REQUIRED TO MAKE YOUR OWN FUEL
I hope this helps someone not making the same idiotic mistake like I did 
Tony
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"Perfection and patience usually walk side by side..." |
