The Behm Acoustic Sounder for Airplanes with Reference to Its Accuracy (1930)
NASA Technical Reports Server (NTRS) · leaf 20
Lrection of flight B (By calibration of c- instruments) Impulse Echo microphones =40 m va> hsoll " g m d, h soli h, " =10 m ii =60 n e, c, " =20 m f, =80 m g, hsoll =100 m Fig 4 Sounding error with respect to airplane speed v,and distance a of impulse and echo microphone,represented for v=30…
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