= Catherine B. McGinley
{c}
<Catherine B. McGinley> is identified as a Langley researcher and coauthor with <Dan H. Neuhart> of a 2004 experimental report on <wind-tunnel turbulence intensity>. The primary title page establishes this byline; the report connects the claimed flow quality to a documented measurement procedure.<Free-Stream Turbulence Intensity in the Langley 14- by 22-Foot Subsonic Tunnel by Dan H. Neuhart and Catherine B. McGinley>[Title page and printed pp. 7–9, apparatus and data analysis]{ref}
The experiment used calibrated <hot-wire anemometry> to convert electrical signals into mean and fluctuating <velocity>. Its comparisons included different positions and tunnel operating conditions. Calibration and retained frequency range belong to the interpretation of a turbulence result; the report's Figure 20 explicitly examines bandwidth sensitivity.<Free-Stream Turbulence Intensity in the Langley 14- by 22-Foot Subsonic Tunnel by Dan H. Neuhart and Catherine B. McGinley>[Printed pp. 8–9, hot-wire calibration; Figure 20, integration-bandwidth comparison]{ref}
An original calculation illustrates why a numerical <turbulence intensity> needs a scale. With $TI=u_{\rm rms}/\overline U$, stipulate $u_{\rm rms}=0.020\,\mathrm{m/s}$ and mean <speed> $\overline U=40\,\mathrm{m/s}$. Then $TI=0.0005=0.050\%$. If an independent additive measurement-noise component has RMS $0.015\,\mathrm{m/s}$, the observed fluctuation RMS becomes
$$
u_{\rm obs}=\sqrt{0.020^2+0.015^2}=0.025\,\mathrm{m/s},
$$
giving $0.0625\%$. Subtracting RMS values directly would give the wrong answer; independence permits subtraction of <variances>. These stipulated numbers are not measurements from the report. The example shows why a small recorded fluctuation cannot be interpreted without considering apparatus noise and the measurement model.
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