BillL
Well Known Member
Well, There is a saying - "striving for perfection, oft we mar what is well"
That is an appropriate statement. My OAT probe is located in the wing root cavity aft of the spar. Now in Phase I, some of the first items to be verified are the ASI speeds and OAT accuracy. A K-type thermo couple was placed well outboard on a wing and flight data recorded. It was ok, but today just happened to plot some data on Savvy Analysis. It showed a very surprising result. The OAT is, indeed, affected by the exhaust temps. The low/high range below is 1.0 deg C I don't know the mechanism for the effect, but the data is clear that it does. Having advocated this location before, any such recommendation is retracted until the cause is known. Maybe, this result is specific to the aft-of-spar location, but that will be an edit to this post if data is taken there. For now, it is another issue to be evaluated on the squawk list.
That is an appropriate statement. My OAT probe is located in the wing root cavity aft of the spar. Now in Phase I, some of the first items to be verified are the ASI speeds and OAT accuracy. A K-type thermo couple was placed well outboard on a wing and flight data recorded. It was ok, but today just happened to plot some data on Savvy Analysis. It showed a very surprising result. The OAT is, indeed, affected by the exhaust temps. The low/high range below is 1.0 deg C I don't know the mechanism for the effect, but the data is clear that it does. Having advocated this location before, any such recommendation is retracted until the cause is known. Maybe, this result is specific to the aft-of-spar location, but that will be an edit to this post if data is taken there. For now, it is another issue to be evaluated on the squawk list.
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