eanderson@carolina.rr.com
----- Original Message -----
From: "Finn Lassen" <finnlassen@netzero.net>
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
Sent: Saturday, June 28, 2003 12:17 AM
Subject: [FlyRotary] N993FL (RV-3) Data collection


> I finally got around to adding a serial port to my engine monitor and
> just finished writing a little VB program for my iPaq PocketPC that
> captures the serial port input and writes it to a text file.
>  ...SNIP

> For example the EGTs do not track very well. And I have a flaky Center
> carb fuel pressue sensor (or pump) - but I turn that off at safe
> altitude in order to use the center carb to lean out the mixture.
> It would be nice to add altitude, air speed and throttle setting sensors.
> I sure have something wierd going on in my airbox/carbs.
>
> More to come (if anyone are interested).
>
> Finn

Hi Finn,

    Interesting data.  On just a brief glance a couple of things caught my
eye.  First, is an almost 200 rpm drop when doing your ignition check
appears a bit excessive.  My rpm varies approx 50 rpm - barely noticable on
the tach.  Second, a little surprised at the low rpm and fuel flow on take
off compared to mine (5500 rpm 15-16 GPH). Of course, with your lighter
aircraft your performance on takeoff exceeds mine even with the reduced
power.

 Could not tell for certain whether you tried an WOT run but never saw more
than 5660 rpm where as mine will get up to 6100-6150rpm at WOT at 3000 MSL.
I suspect your carburation set up might not be deliverying optimum power,
but that is just my opinion.  Keep the data coming.  barometric pressure
might also be a nice parameter to capture, I saw your 165IAS which may or
may not be impressive depending on what altitude you were at..

Best Regards

Ed Anderson