🚀 go-pugleaf

I'm looking for help on the following: I would like to get/make an
airspeed sensor for R/C models. This would require 1) a small
accurate (and light!) pressure sensor that would run off a small set
of batteries, and 2) a similarly small, light, low-power way to get
the information down to earth. I'm thinking of having the output be
a tone whose frequency is proportional to the airspeed. Does anyone
know of such a system, or where to look for the individual pieces?
Comments?? 

Thanks.

Scott Dynes