<DOC>
<DOCNO>
239
</DOCNO>
<TITLE>
design and calibration at low speeds of a static tube
and a pitot-static tube with semi-ellipsoidal nose
shapes .
</TITLE>
<AUTHOR>
kettle,d.j.
</AUTHOR>
<BIBLIO>
rae tn.aero.2247, 1953.
</BIBLIO>
<TEXT>
  a new static tube and a new pitot-static tube have been designed and
calibrated in the no.1 and the no.2 11 ft x 8 ft wind tunnels of the
r.a.e., using a long static tube, the error of which is believed to be
very small, as a standard for comparison .
  the results show that the static pressure measured by these tubes
is in error due to the supporting strut and to the nose shape of the
tube by an amount which may be calculated for positions of the static
slot, or holes, greater than 10 tube diameters ahead of the strut .  the
readings show no measurable scale effect in the speed range 100-230 ft
sec .  the static tube is insensitive to yaw in the range 1 with a
square-edged slot and is even less sensitive to yaw when the slot edges
are rounded .  the turbulence of the tunnel has an effect on the static
pressure reading .
</TEXT>
</DOC>
