In Pursuit of the Bomb — Charles Dechert

Charlie Dushet (Chet) was amazed how much demand there was for his two-man submersible, especially from the Navy. In the last three weeks, he'd been to San Dablo twice with his sub at the request of Admiral Hawkins, who asks him to secretly recover a Russian weapon that fell overboard from his aircraft carrier. With the help of two female divers and his friend Captain Jake, they play a cat and mouse game with a ruthless submarine trying to retrieve the weapon first. They get torpedoed but survive by quick thinking and lots of luck. Along with his two friends, Rusty, a fiery red-head and his Indian friend Fuzz, they get drawn into the dangerous world of scuba diving and stolen plutonium. Will Chet be able to rescue the scuba diver trapped underwater, and also disarm the explosives he stumbles upon when terrorists try to sink the admiral's aircraft carrier?
Later, Chet's Wyoming fabrication business is hired to build an ionization chamber for a foreign research team. The strange thread design and their payment in diamonds starts Chet to thinking the chamber may have a far more sinister use. With the help of Admiral Hawkins, Chet gets drawn into the dark underworld of international terrorists, nuclear bombs, and stolen diamonds. Things go south when they lose the bomb's location in the middle east. Will he have enough luck to find the bomb and disarm it in time?