GERMAN FUZES

German bomb fuze types included time fuzes, impact fuzes, anti-disturbance, air burst and mechanical time fuzes. Whilst some were chemical or mechanical in action, most German bomb fuzes differed from those used by other countries, being predominantly of electric design.

An electric fuze needs to receive an electric charge to allow it to become active. This is designed into a mechanism on an aircraft where a charge is delivered to the bomb just as it is dropped. The charge was delivered via a plug on an arm which was in turn connected to the top of the fuze and pulled free when the bomb was released.

The electric type fuze has a number of advantages over mechanical types, including ease of production, simplicity of manufacture and being safe to handle and transport as the bomb does not become armed until it receives its electric charge.

Anti-handling fuzes were developed specifically to function after the bomb had been dropped and the fuze armed. This type of fuze was designed to kill anyone attempting to disarm the bomb.

Another device, the Zusatzzünder Zusz (40), commonly known as the Zus 40, which was developed and designed to be placed underneath an electric time fuze, or the Langzeitzünder 17. This caused the bomb to detonate if the fuze was withdrawn.

As part of the aircraft bomb arming system, a main electric fuze is required to be set to ‘on’. This allows an electrical charge to be passed to the electrical charging connector incorporated into the bomb shackle. When the bomb is dropped, an electric charge is passed to a storage condenser in the fuze. The electric charge within the storage condenser then leaks through to a firing condenser, causing a delay before the fuze is armed.

The firing condenser is connected to trembler switches and on impact they connect to the fuze igniting circuit, firing a flash pellet which causes the bomb to detonate via its explosive train.

The Germans utilised a number of different types of bomb cradle, each designed to cater for the different type of bomb used. Bombs could be carried internally, in an internal bomb bay, or on external bomb stations.

The development of larger bombs required them to be carried externally as they were too large for the internal bays of Luftwaffe bomber aircraft which had all been designed to carry smaller bombs.

■ An electrical charging cap. This was fitted to the bomb fuze to charge bomb fuze condensors and was attached to a fitment in the aircraft. Its two contacts came into contact with the terminals on the top of the fuze and pulled away on bomb release. ■ Above right: An example of an electric bomb fuze and a technical drawing of a C50 type electric fuze. This type of fuze was an anti-disturbance fuze designed to detonate the bomb is moved. As such, it was designed to kill anybody trying to defuse the bomb – normally a bomb disposal team member. ■ A diagram showing the Zus 40 and how it functions. When the fuze which it sits underneath is removed, a spring loaded arm is released (A) which moves horizontally and opens the firing channel and allows a spring loaded striker to hit the detonator which then detonates the bomb.

■ A diagram showing detail of how the clamp is fitted to the bomb.