WWII ERA German ECR Fuze

Germany Following WWI, Germany was forbidden to manufacture weapons of war but the restriction was not always followed. In 1930, Hubert Ruhlemann designed the ECR or Electrical, Condenser ,Resistance fuze which was tested between 1931 and 1932 in Russia. The ECR fuze was designed for use on aerial dropped bombs. The fuze was connected to the aircraft and electrically charged (i.e., energized) before leaving the aircraft. As the bomb fell to earth, the electric charge would trickle through various resistors to a firing condensor. The impact of the bomb caused a sensitive vibrator switch to close the circuit and detonate the bomb through a firing bridge (similar to a match head) which created a flash that detonated the sensitive penthrite wax contained in the attached gaine, which is the steel or bakelite container screwed into the base of the fuze.

Shown below is a German 50kg bomb (without the fins) with a Type 25B ECR fuze.

There were various models of ECR fuzes manufactured, usually constructed from aluminum (steel versions were also available), the fuze came in two parts, the top part or Switch Block which contained the pins to connect the bomb to the aircraft and trembler switches. The bottom part contained the resistors and capicitors. At the very bottom of the case is a screw thread where the gaine (booster) was attached. The fuze measured 110 mm long by 50mm wide.

Shown below is a ECR fuze with a gaine attached and a cutaway of the fuze itself.

Article submitted by:
Steve Venus
www.bombfuzecollectorsnet.com