In October 1987, a fleet of up to 24 boats stretched across the full width of Loch Ness and swept the entire loch with sonar — the largest scientific survey of the lake ever conducted.

It was called Operation Deepscan.

Most people have heard of it. Almost nobody understands the data.

The Three Contacts That Survived

Out of thousands of sonar returns, the team identified three contact events that could not be explained by known geology, thermocline artefacts, fish shoals, or equipment error.

Contact Events 014, 017, and 019 all shared the same characteristics:

• Large target strength (−18 to −24 dB) — bigger than any known fish in the loch

• Doppler shifts of 0.5–1.2 m/s — indicating a moving biological target

• Multi-vessel confirmation — detected on two or more boats simultaneously

• Passed environmental validation — not explained by thermoclines, seiches, or bottom features

These contacts were never published in full detail. The original team lacked the time and funding to complete the analysis.

Why This Matters Now

The raw data still exists. The techniques for analysing it have improved enormously. And the analytical framework — multi-beam triangulation, Doppler correction, environmental validation — is now standard practice in marine biology and defence sonar.

What's missing is trained analysts who know how to read these specific logs.

What I Built

I created the Nessie Sonar Contact 1987 Expedition Logs — Advanced Pro Certification to train people in exactly this skillset:

• Freshwater sonar operations and the 1987 hardware

• Contact event analysis with real expedition data

• Hydroacoustic signature classification

• Deep-water anomaly triangulation and tracking

• The full six-point environmental validation checklist

This is not a casual overview. It's a six-module certification with a practical case study final. You'll be held to the same analytical standard as the original expedition scientists.

If you've ever looked at a Loch Ness sonar image and wondered what you were actually seeing — this is where you learn to read it properly.

The course is live now inside Nessie Sonar Academy.