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Date: Sun, 19 Aug 2012 14:18:43 -0400
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Subject: Re: [LML] Re: Question about TAS Error (and Winds Calculation) based on OAT (in a LIVP)
From: Ronald STEVENS <Ronald@sdc.com>
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Actually those are not bad calculation results. I have seen similar even =
in a cirrus. (about 7-10kts off). So I do not think it is worth going =
through the hassle of changing the location.

I would start doing work when it would have been more then 15kts off. =
You will see that the TAS calculation also differs at high or low speed. =
(do the same at the same level at 110kts IAS and once at 170IAS) and if =
you did you will see that the spread also is different, so when it =
really matters a lot (traffic pattern) it will be close to what it =
should be (that were my observations when I did the calcs)

=3D=3D Ronald
=20

On Aug 19, 2012, at 9:36 AM, jeffrey liegner wrote:

> Recall my question (same subject) about the accuracy of OAT, and its =
efect on TAS and Winds.  SInce I rendere pireps including winds and OAT, =
the accuracy of this report is now in question.  Many have suggested =
reloacting the OAT to another place, different from the Lancair =
recommendation along the fuselage.  This is not an easy thing, putting =
the probe out on the wing, wiring coming into and through the wing root, =
into the pressure vessel (different from the current OAT location).
>=20
> I performed the flight TAS calculation recommended by several.  =
Whether three measurements with headings 120 degrees apart, or three =
orthogonal headings, the results are the same.
>=20
>=20
> The Chelton presents a TAS 216 and the calculator renders TAS 205 =
based on the n flight measurement.
>=20
> I wonder if I can change the compressibility quotient used by Chelton =
to adjust the OAT reading.
>=20
> Suggestions?
>=20
> Jeff L
> N334P
>=20
> --
> For archives and unsub =
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