REFLECTOR: Exhaust systems
Simon Aegerter
reflector@tvbf.org
Fri, 11 Jul 2003 16:17:07 +0200
>After all, 3 does divide evenly into 6.
You are absolutely right, Dale.
A 6-cylinder engine fires 6 times during 2 full turns, that is 720
degrees. 720/6 = 120. That means, the blasts are seperated by 120
deg. That happens to be the spacing of the blades of a 3-blade prop.
So. with a 6 cyl. engine and a three bladed prop you can have the
blast in one of two places: onto the blades or between them,
depending on how you mount the prop. Presto!
I have not flown a whole lot of hours since I turned my exhausts
(3-in-1) backwards but I see no charring, just some soot.
Somebody asked about a 4-bladed prop. Same argument, different
result: a 4-cyl fires 4 times in two turns - so 180 deg apart. unless
you have 8 ways to mount your prop, you are making sure that at least
two blades are hit every two turns.
Best
Simon
--
Simon Aegerter, Wollerau, Switzerland