The most persistent, identifiable feature on intensity and phase scintillation records of coherent beacon signals recorded near Fairbanks, Alaska during several months in 1976 is a narrow region of enhanced scintillation to the south of the station. On high-elevation passes the feature occurs near the magnetic zenith, suggesting that it could be a geometric enhancement produced by field-aligned irregularities. The feature also occurs, however, on medium and low-elevation passes when the minimum off-field angle is several tens of degrees. The observations, therefore, represent evidence for either (1) a hitherto unrecognized irregularity enhancement or layer thickening in the subauroral ionosphere, or (2) longitudinally extended irregularity sheets. ¿ 1977 American Geophysical Union