Replete with quotes from Curtis LeMay, Robert S McNamara and other officials of the Cold War era, The Penetrators was the kind of detailed, political-military thriller which later became characteristic of Tom Clancy.
The book also strongly argued the case for the US's crewed long-range bomber force, which was then in danger of being phased out in favour of ICBMs.
Based on his own novel of the same title, Searls wrote the screenplay for the 1978 Angie Dickinson television movie Overboard.
Searls' other military and aviation-themed novels included: The Astronaut (1962), Pentagon (1971), Hero Ship (1969), The Big X (1959), and Altitude Zero (1991).
In the book Console Wars (2014) by Blake Harris, the popular Sega Genesis game Ecco the Dolphin (1992) is said to be inspired by Searls' novel "Sounding", though the reference is anonymized.