Narrative:

[While] being vectored for the ILS runway 15R bos; cleared from 4000 ft to 3000 ft. Encountered windshear/wake turbulence and aircraft lost 700 ft. ATC queried altitude and [I] leveled back to 3000 ft.

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Original NASA ASRS Text

Title: C402 pilot reported encountering wake turbulence and/or windshear on approach to BOS that resulted in a loss of 700 ft.

Narrative: [While] being vectored for the ILS Runway 15R BOS; cleared from 4000 ft to 3000 ft. Encountered windshear/wake turbulence and aircraft lost 700 ft. ATC queried altitude and [I] leveled back to 3000 ft.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.