Vixen 03 by Clive Cussler

When a top-secret experimental aircraft disappears under mysterious circumstances, a daring marine engineer and his oceanographic agency follow a trail of wreckage and witnesses that leads to a deadly international conspiracy; as they hunt for the truth across treacherous seas and hostile territory, they uncover government cover-ups, ruthless killers and a plot that could spark wider conflict, forcing a race against time that combines high-tech salvage, naval action and sudden personal danger.

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