Sun 13 Dec 2015:
GREAT NEWS (4 years and 3 days since the day we decided to start building the Bleriot…)
Yesterday I suddenly remembered some answers I got from Chad, my propeller man (see Mon 4 Nov 2013 above) in the early stages when I was discussing a propeller for my Bleriot in relation to the propeller speed. Have a read (4 Nov 2013 above here on this page) if you are interested. But this is basically what what he said:
The diameter is critical in antique prop design because diameter is leverage and leverage is the most important aspect of good design for high drag antiques. If the prop rpm is lower it means that leverage is greater, an ideal situation for high drag airframes.
And an earlier comment from him:
Gert, People that are not familiar with antique airplanes often think horsepower ratings matter. It doesn’t. Cubic inch displacement and prop diameter matter and these are unrelated to horsepower.
So yesterday I told him about my suspicions of the carburetor and my findings with the propeller speed of about 1500 rpm.
Chad came back to me this morning;
He thinks the 1500rpm is a bit low, but only marginal. He designed it to go about 1575 to 1675rpm. Also he doubts that I am having primer valve leaks, as that would effect the engine speed. Also and I knew this, when flying, it will speed up a little bit more.
He really thinks that the prop is still developing the necessary torque to fly well.
Now I didn’t tell him this, but the first time I saw the tacho speed, the engine went up to about 1600rpm, which is exactly what he designed it for !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! 🙂 🙂 🙂
So I guess we need to try and fly this machine 🙂
I will tell my test pilot.