They *were* using British technology to build the thing. The bolt that failed, or some component of the detonation system, probably said LUCAS on it. If they'd been using American tech, the explosive bolt would have worked, since *we* figured those out back in the 60s.
WE? Americans ? You mean, Wernherr von Braun and it's staff of German Engineers.
Americans couldn't even get a Jet engine working.
Please, You Americans twist the History to your end enough already, stay on course with those things you won't make a complete ass out of you.