X-Mozilla-Keys:                                                                                 
Perry Mick wrote:

Paul wrote:

Tracy Crook wrote:

Perry,  did you ever use the performance monitor to calculate horsepower?  I
thought that was its most  useful function but I never heard you mention
using it in that mode.

There are some functions in that thing that would be useful,
like 0-60mph time, quarter mile time and distance, and the HP
function you mention.  However, I haven't been able to get those
to work in the plane yet.  They do work when I use it in my car.
When I punch the throttle to start rolling, there is apparently  
enough up and down motion to throw the thing for a loop, it   
doesn't realize that I'm rolling and so it doesn't start the    
data collection and calculations.  The data I took previously
was just reading the instantaneous G from the display, which
seems to work ok but is also very sensitive to pitch variation.  

My plane has been down for a couple weeks now, making fuel 
system mods, so haven't taken any more data or tried to make the
thing work better.

The HP function would do you no good as you need to know the 
exact drag of the airplane and the incremental drag from the duct.
If you knew this you could derive the net thrust HP out of
the duct from the accelleration data.

(HP /Velocity in FPS)- Drag = NetExcessThrust.

Accelleration (in G's) =  NetExcessThrust / Weight 

The accelleration data is the bottom line. If it is not 
accellerating you are at the top speed  of the airplane and 
you ain't gon'a fly. Breaking the laws of physics will not
be tolerated. The penalty for doing so is death :-)

Paul Lamar
 
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