A lot of homebuilt aircraft use two aluminum tubes.  One facing forward and
one pluged in the front and small holes drilled in te side.  Hook one up to
each side of a differential pressure transducer.  Should be pretty acccurate
and easy to build.

Mark Willis wrote:

> Andy, consider making your own with a piece of 3-5mm Brass tubing
> swaged down to 1mm or so, a differential pressure transducer, and a bit
> of elbow grease?  (Vent the transducer into a 'pore' on the side of the
> body of the airplane, same as larger aircraft do it.)
>
>   At http://www.instrumentation2000.com/catalog/pressure/09/020958a.html
> they have a micro-manometer that measures either -14" H2O..+14" H2O, OR,
> velocities up to 15,000 fpm.  Seems to me that you could start off by
> making your own system, "wind tunnel" test the system (read: Drive
> around like a madman, with the rig stuck on a pole sticking up off the
> front bumper of your car, to give you some good velocity calibrations),
> and call it good.  I'm suspecting a lower pressure range might do you,
> though <G>  Start out guessing that 1" H2O = 1,071 fpm, roughly <G>
>
>   (Under constant velocities, the reading will be accurate, smaller
> pitot tube will just make the system read a little "laggier", is all.)
>
>   Mark
>
> Andy Kunz wrote:
> >
> > Anybody know of small (3-5mm dia) pitot tubes for a PIC-based project?
> >
> > Thanks.
> >
> > Andy
> >
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