In the Independent, David Keys talks about the Grand Slam, the largest conventional bomb of WW2:
The final secrets of Britain’s largest-ever conventional weapon of war are being ‘unearthed’ by archaeologists.The 70 ft deep and 130 ft diameter crater which Grand Slam created in the New Forest on 13 March 1945 – with the target building in the background (Crown Copyright)
Geophysics experts are using ground-penetrating radar and other high tech methods to ‘x-ray’ the ground, in a remote area of the New Forest in Hampshire, to shed new light on the most powerful top secret World War Two weapon test ever carried out in the UK.
The weapon – a bomb designed by the British aircraft and munitions inventor, Barnes Wallis, and codenamed ‘Grand Slam’ – was almost 26 foot long and weighed 22,000 pounds, substantially bigger than any other wartime explosive device ever developed by Britain.
The New Forest test is historically important because it heralded an expansion in the crucial strategic air offensive against key infrastructure targets in Nazi Germany. The first RAF bomber command Grand Slam sortie got underway within hours of the successful test of the bomb.
Four geophysical techniques – ground penetrating radar, magnetometry, electrical resistivity and electrical resistivity tomography – are being used by the archaeologists to assess the damage done to the large concrete target building which has lain buried under a vast mound of earth for the past 66 years.
