History

OptiFuel Design History

To all pilots out there, I am sure that you have experienced the stress of not knowing if you could make your destination or not due to fuel planning. You still continue with your flight because you still hope to make it, and also because there is no obvious evidence that you should not make it. What happened to me is a bit different.

On a cross-country flight, I planned to land at an airstrip that was well documented. At the airstrip I would transfer fuel from spare tanks into the main one, and continue with my flight. I calculated that I would have about 10 litres left in reserve at the time and that the extra fuel from my spare tanks would take me to my destination on the second leg.
When my GPS took me over the so-called airstrip, I was horrified to see rows and rows of houses! The airstrip was abandoned 2 years before and no database and maps mentioned that.

I went in search of an adequate place to do a precautionary landing because I knew that my fuel was low by now. I was under pressure and things had to happen quickly. After 15 minutes, at last I found a grazing field filled up with recently harvested bales. Luckily I found a stretch of 150 meters amongst the bales that was not obstructed. I did a few low passes like precautionary landings call for and I landed safely. My wife was my passenger, praying all along the process.

Only then could I see the real level of my fuel, and I had 18 litres left! If I had known that, I would have flown for longer to be able to take a better decision. In rushing as I did I could have broken my aircraft or worse, injure my wife and myself. The rest of the flight went as planned and in short, I was very lucky.
The problem with my aircraft is that it has a very poor tank level readout, and it only works reasonably when the aircraft is still on the ground. Obviously, other planes have much better dials, but how accurate are they really ?

As flying is really a hobby and I am an electronic designer by profession, I swore that day that as soon as I would arrive at my destination I would immediately design a fuel computer for my own use. I was very busy at work at the time to also get involved in marketing such a product, so that was not a priority for me. I looked at various instruments on the market and was not happy with the calibration process and the inaccuracy of the fuel impellers (sensors). I therefore asked my son to design the impeller as he already designed a similar unit used in rally racing cars. It is used to meter the amount of water injected in turbocharged engines to prevent detonation. I did the rest of the electronics and microprocessor software.

I used the prototype instrument in my aircraft for the following 3 years and relied 100% on it for my flights and fuel planning. The peace of mind in doing long trips changed drastically my stress level while doing such flights. I did along the years some software changes to give me more information as a pilot, but still very conscious of not clogging the instrument with useless gadget type information.

As I was always the only user of such a unit, I had the privilege of having something unique, yet simple and effective.

Now is the time to share it with other pilots, after 3 years of proving itself.

Magni gyrocopter used for prototyping

Jean-Pierre , Pilot and Optifuel designer

Installation of flow sensor on Rotax 914

Flow sensor design history

The flow sensor was initially designed for accurate and quick water metering for the Aquamist water injection system(http://www.aquamist.co.uk/index.html) , designed and manufactured by Richard Lamb for use in turbo charged engines to retard detonation.

February 2002 Race Tech magazine feature of the Birmingham Autosport Show