Many PPG Pilots have problems estimating the remaining fuel quantity in flight. Most of them base their fuel consumption on time calculations. It is an easy way and it is done experimentally.The only drawback of this is that fuel consumption is directly proportional with the power setting. More power means more fuel consumption and vice-versa. This method of estimation is not very accurate and some pilots may run out of fuel in the least expected and sometimes critical moments of the flight. (Murphy's Law)
There are a few paramotors that have a built in fuel gauge but this usually signals when the fuel is very low. This system uses a very bright diode and a fuel sensor in the tank.( all my Fly units have this device)
A few years ago, when I started some cross country flights, I was always nervous not knowing if the fuel would be enough to get back to the field. I built a very simple optical device which enables me to monitor my fuel consumption in flight.
This system can be used only if a transparent/translucent fuel tank is employed.
When I fly cross country, I only use up 1/3 -rd of my fuel. Once I reach this level, I turn back. I always have plenty of gas left. This method I have used in boating as well and I have never run out of fuel on the water or in the air.
The retractable mirror needs very few parts and they can be easily purchased in auto parts stores.
They are: a round convex mirror of 2,5-3" diameter, a retractable key chain, soft steel braided cable (used in fishing for strong leaders) and a crimp (also used in fishing)
Building the mirror
Using a Dremel , drill two holes in the back cover of the convex mirror. Great care is required, not to damage the silver coating of the mirror.
Cut the braided steel cable to about 1,5-2" and insert it through the two drilled holes. Insert crimp on one end.
Please see picture below:
Next, pull out about 5-6 inches of chain and block it with a paper clip. This will facilitate the next step. (see picture)
Insert the other end of the braided cable into the crimp as shown below:
The mirror can be easily attached to the harness. Since my AIRFER Tornado has the throttle on the right side, the mirror is attached to the left side of the harness. It can be easily extended to check to fuel level. When released, it automatically retracts.
Note: the bigger the mirror, the bigger and more clear the image will be.
This system is very easy to build and will eliminate any guessing. The pilot will always know how much fuel is left in the tank and will gain more confidence while flying. The total cost of this device is about $9-10.
Build one and you will like it.