ANOMALY
ARCHIVE / 001
← ENCOUNTERS DIRECTORY
ENC-902421LANDMARK CASE · HIGH CORROBORATIONDATE PRECISION: exactRECORD COMPLETENESS: 100%

Sylvan Lake Surface Disturbance and Sonar Search

July 27, 2009Sylvan Lake, Minnesota, Minnesota, United States

Witness reported a linear surface disturbance, outward waves and a rotating circle in Sylvan Lake. Sheriff/fire dive teams found no crashed helicopter; side-scan sonar later returned one manufactured-looking anomaly near the marked area.

// LINKED CLASSIFICATIONS:Scientific & Observational Types(P-000101)→
Claims are displayed with the source wording, locator, relationship and verification state. Competing claims remain separate rather than being averaged into a single answer.
SOURCE COMPARISON

Encounter · New Insights case observation

HOW TO READ THIS →
CLAIM-216206reported
“The primary witness denied seeing anything crash or splash into Sylvan Lake. She instead reported a roughly 30-foot line on the surface, two approximately 12-inch waves moving outward in opposite directions, and a counterclockwise circular swirl after the line disappeared.”
Inside the U.S. Government Covert UFO Program: New Insights
SRC-002150 · uploaded PDF pp. 105-106; printed pp. 94-95
SUPPORTS
SOURCE COMPARISON

Encounter · New Insights investigation finding

HOW TO READ THIS →
CLAIM-216207reported
“Forest Lake Fire Department dive rescue and Washington County Sheriff dive teams searched for several hours and found no evidence of a crashed helicopter.”
Inside the U.S. Government Covert UFO Program: New Insights
SRC-002150 · uploaded PDF pp. 105-105; printed pp. 94-94
CONTEXTUALIZES
CLAIM-216208reported
“A deputy reportedly made eight side-scan-sonar passes and recorded one anomaly about 30 yards from a witness-guided marker, described in the sheriff report as roughly dryer/washing-machine sized, not rounded, and apparently manufactured in origin.”
Inside the U.S. Government Covert UFO Program: New Insights
SRC-002150 · uploaded PDF pp. 106-106; printed pp. 95-95
SUPPORTS
CLAIM-216209reported
“The investigation concluded there was no evidence supporting a crash into the lake, while the surface events observed by the witness remained unexplained.”
Inside the U.S. Government Covert UFO Program: New Insights
SRC-002150 · uploaded PDF pp. 106-106; printed pp. 95-95
CONTEXTUALIZES
Multiple claim rows are intentionally retained when sources disagree. ANOMALY does not silently reconcile competing values.
SOURCE COMPARISON

Sylvan Lake Surface Disturbance and Sonar Anomaly (2009) · New Insights reported subject characteristics

HOW TO READ THIS →
CLAIM-216250reported
“The Sylvan Lake witness described a roughly 30-foot line on the water surface, outward-moving waves on both sides and a counterclockwise swirl; she explicitly said she did not see anything crash or splash into the lake.”
Inside the U.S. Government Covert UFO Program: New Insights
SRC-002150 · uploaded PDF pp. 105-106; printed pp. 94-95
SUPPORTS