REFLECTOR:Static Port
Wayne Owens
reflector@tvbf.org
Fri, 4 Jul 2003 16:50:48 -0400
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Wasn't too clear was it.
My TAS was reading higher than my average GPS ground speed over a =
course.
I experimented by adding a layer or two of duct tape to my bump to =
confirm what happens. The static pressure was lowered so the delta P =
over the airspeed indicator (scale) was greater. The air speed read =
higher still. It confirmed I needed to sand off some more of my =
fiberglass bump.
----- Original Message -----=20
From: "Scott Derrick" <scott@tnstaafl.net>
To: <reflector@tvbf.org>
Sent: Friday, July 04, 2003 4:12 PM
Subject: Re: REFLECTOR:Static Port
> Ok, let me get this straight...
>=20
> Raising the bump will raise the static pressure thus lowering your=20
> indicated airspeed?
>=20
> Lowering the bump will lower the static pressure thus raising your=20
> indicated airspeed?
>=20
> Scott
>=20
>=20
> Wayne Owens wrote:
> > Applying a layer of duct tape over the bump should make it read =
higher.
> > Sanding it off about 0.015 inch at a time should lower your =
indicated
> > airspeed.
> > Wayne
> > ----- Original Message -----=20
> > From: "Scott Derrick" <scott@tnstaafl.net>
> > To: <reflector@tvbf.org>
> > Sent: Thursday, July 03, 2003 10:25 PM
> > Subject: REFLECTOR:Static Port
> >=20
> >=20
> >=20
> >>In this months Sport Aviation there is an article on how to =
calibrate
> >>your airspeed indicator. The article mentions that the most often
> >>problem with incorrect airspeed indicators is the static port not
> >>providing a true static pressure.
> >>
> >>I'm sure mine is off at cruise speeds. I think it reads a lower =
pressure
> >>than it should thus causing the airspeed indicator to register a =
higher
> >>indicated speed than it should.
> >>
> >>I have the standard 3 tiny holes in a vertical pattern with a small
> >>aluminum block in front of the holes. This is located about 10 =
inches
> >>below the pilot side elevator on the fuselage.
> >>
> >>Any body else determine theirs was not optimal? Any easy fixes?
> >>
> >>Scott
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<DIV><FONT face=3DArial size=3D2>
<DIV>Wasn't too clear was it.</DIV>
<DIV> </DIV>
<DIV>My TAS was reading higher than my average GPS ground speed over a=20
course.</DIV>
<DIV>I experimented by adding a layer or two of duct tape to =
my bump=20
to confirm what happens. The static pressure was lowered so the =
delta P=20
over the airspeed indicator (scale) was greater. <FONT=20
color=3D#ff0000>The air speed read higher still.</FONT> It =
confirmed I=20
needed to sand off some more of my fiberglass bump.</DIV>
<DIV> </DIV>
<DIV>----- Original Message -----=20
<DIV>From: "Scott Derrick" <<A=20
href=3D"mailto:scott@tnstaafl.net">scott@tnstaafl.net</A>></DIV>
<DIV>To: <<A=20
href=3D"mailto:reflector@tvbf.org">reflector@tvbf.org</A>></DIV>
<DIV>Sent: Friday, July 04, 2003 4:12 PM</DIV>
<DIV>Subject: Re: REFLECTOR:Static Port</DIV></DIV>
<DIV><BR></DIV>> Ok, let me get this straight...<BR>> <BR>> =
Raising the=20
bump will raise the static pressure thus lowering your <BR>> =
indicated=20
airspeed?<BR>> <BR>> Lowering the bump will lower the static =
pressure thus=20
raising your <BR>> indicated airspeed?<BR>> <BR>> Scott<BR>> =
<BR>> <BR>> Wayne Owens wrote:<BR>> > Applying a layer of =
duct tape=20
over the bump should make it read higher.<BR>> > Sanding it off =
about=20
0.015 inch at a time should lower your indicated<BR>> > =
airspeed.<BR>>=20
> Wayne<BR>> > ----- Original Message ----- <BR>> > From: =
"Scott=20
Derrick" <<A=20
href=3D"mailto:scott@tnstaafl.net">scott@tnstaafl.net</A>><BR>> =
> To:=20
<<A =
href=3D"mailto:reflector@tvbf.org">reflector@tvbf.org</A>><BR>> =
>=20
Sent: Thursday, July 03, 2003 10:25 PM<BR>> > Subject: =
REFLECTOR:Static=20
Port<BR>> > <BR>> > <BR>> > <BR>> >>In this =
months=20
Sport Aviation there is an article on how to calibrate<BR>> =
>>your=20
airspeed indicator. The article mentions that the most =
often<BR>>=20
>>problem with incorrect airspeed indicators is the static port=20
not<BR>> >>providing a true static pressure.<BR>> =
>><BR>>=20
>>I'm sure mine is off at cruise speeds. I think it reads a lower=20
pressure<BR>> >>than it should thus causing the airspeed =
indicator to=20
register a higher<BR>> >>indicated speed than it =
should.<BR>>=20
>><BR>> >>I have the standard 3 tiny holes in a vertical=20
pattern with a small<BR>> >>aluminum block in front of =
the=20
holes. This is located about 10 inches<BR>> >>below =
the=20
pilot side elevator on the fuselage.<BR>> >><BR>> =
>>Any body=20
else determine theirs was not optimal? Any easy fixes?<BR>>=20
>><BR>> >>Scott<BR></FONT></DIV></BODY></HTML>
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